Merge branch 'master' into fixes/7147-combobox-transform

native/Avalonia.Native/src/OSX/Avalonia.Native.OSX.xcodeproj/project.pbxproj

@@ -7,6 +7,14 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		18391068E48EF96E3DB5FDAB /* ResizeScope.mm in Sources */ = {isa = PBXBuildFile; fileRef = 18391E45702740FE9DD69695 /* ResizeScope.mm */; };
+		1839125F057B0A4EB1760058 /* WindowImpl.mm in Sources */ = {isa = PBXBuildFile; fileRef = 183919BF108EB72A029F7671 /* WindowImpl.mm */; };
+		183916173528EC2737DBE5E1 /* WindowBaseImpl.h in Headers */ = {isa = PBXBuildFile; fileRef = 183915BFF0E234CD3604A7CD /* WindowBaseImpl.h */; };
+		1839171DCC651B0638603AC4 /* INSWindowHolder.h in Headers */ = {isa = PBXBuildFile; fileRef = 18391BBB7782C296D424071F /* INSWindowHolder.h */; };
+		1839179A55FC1421BEE83330 /* WindowBaseImpl.mm in Sources */ = {isa = PBXBuildFile; fileRef = 18391676ECF0E983F4964357 /* WindowBaseImpl.mm */; };
+		183919D91DB9AAB5D700C2EA /* WindowImpl.h in Headers */ = {isa = PBXBuildFile; fileRef = 18391CD090AA776E7E841AC9 /* WindowImpl.h */; };
+		18391C28BF1823B5464FDD36 /* ResizeScope.h in Headers */ = {isa = PBXBuildFile; fileRef = 1839171D898F9BFC1373631A /* ResizeScope.h */; };
+		18391CF07316F819E76B617C /* IWindowStateChanged.h in Headers */ = {isa = PBXBuildFile; fileRef = 183913C6BFD6856BD42D19FD /* IWindowStateChanged.h */; };
 		1A002B9E232135EE00021753 /* app.mm in Sources */ = {isa = PBXBuildFile; fileRef = 1A002B9D232135EE00021753 /* app.mm */; };
 		1A1852DC23E05814008F0DED /* deadlock.mm in Sources */ = {isa = PBXBuildFile; fileRef = 1A1852DB23E05814008F0DED /* deadlock.mm */; };
 		1A3E5EA823E9E83B00EDE661 /* rendertarget.mm in Sources */ = {isa = PBXBuildFile; fileRef = 1A3E5EA723E9E83B00EDE661 /* rendertarget.mm */; };
@@ -35,6 +43,14 @@
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
+		183913C6BFD6856BD42D19FD /* IWindowStateChanged.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = IWindowStateChanged.h; sourceTree = "<group>"; };
+		183915BFF0E234CD3604A7CD /* WindowBaseImpl.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = WindowBaseImpl.h; sourceTree = "<group>"; };
+		18391676ECF0E983F4964357 /* WindowBaseImpl.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = WindowBaseImpl.mm; sourceTree = "<group>"; };
+		1839171D898F9BFC1373631A /* ResizeScope.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ResizeScope.h; sourceTree = "<group>"; };
+		183919BF108EB72A029F7671 /* WindowImpl.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = WindowImpl.mm; sourceTree = "<group>"; };
+		18391BBB7782C296D424071F /* INSWindowHolder.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = INSWindowHolder.h; sourceTree = "<group>"; };
+		18391CD090AA776E7E841AC9 /* WindowImpl.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = WindowImpl.h; sourceTree = "<group>"; };
+		18391E45702740FE9DD69695 /* ResizeScope.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ResizeScope.mm; sourceTree = "<group>"; };
 		1A002B9D232135EE00021753 /* app.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = app.mm; sourceTree = "<group>"; };
 		1A1852DB23E05814008F0DED /* deadlock.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = deadlock.mm; sourceTree = "<group>"; };
 		1A3E5EA723E9E83B00EDE661 /* rendertarget.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = rendertarget.mm; sourceTree = "<group>"; };
@@ -130,6 +146,14 @@
 				37C09D8721580FE4006A6758 /* SystemDialogs.mm */,
 				AB7A61F02147C815003C5833 /* Products */,
 				AB661C1C2148230E00291242 /* Frameworks */,
+				18391676ECF0E983F4964357 /* WindowBaseImpl.mm */,
+				183915BFF0E234CD3604A7CD /* WindowBaseImpl.h */,
+				18391BBB7782C296D424071F /* INSWindowHolder.h */,
+				183919BF108EB72A029F7671 /* WindowImpl.mm */,
+				18391CD090AA776E7E841AC9 /* WindowImpl.h */,
+				183913C6BFD6856BD42D19FD /* IWindowStateChanged.h */,
+				18391E45702740FE9DD69695 /* ResizeScope.mm */,
+				1839171D898F9BFC1373631A /* ResizeScope.h */,
 			);
 			sourceTree = "<group>";
 		};
@@ -150,6 +174,11 @@
 			files = (
 				37155CE4233C00EB0034DCE9 /* menu.h in Headers */,
 				BC11A5BE2608D58F0017BAD0 /* automation.h in Headers */,
+				183916173528EC2737DBE5E1 /* WindowBaseImpl.h in Headers */,
+				1839171DCC651B0638603AC4 /* INSWindowHolder.h in Headers */,
+				183919D91DB9AAB5D700C2EA /* WindowImpl.h in Headers */,
+				18391CF07316F819E76B617C /* IWindowStateChanged.h in Headers */,
+				18391C28BF1823B5464FDD36 /* ResizeScope.h in Headers */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -229,6 +258,9 @@
 				AB00E4F72147CA920032A60A /* main.mm in Sources */,
 				37C09D8821580FE4006A6758 /* SystemDialogs.mm in Sources */,
 				AB661C202148286E00291242 /* window.mm in Sources */,
+				1839179A55FC1421BEE83330 /* WindowBaseImpl.mm in Sources */,
+				1839125F057B0A4EB1760058 /* WindowImpl.mm in Sources */,
+				18391068E48EF96E3DB5FDAB /* ResizeScope.mm in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

native/Avalonia.Native/src/OSX/INSWindowHolder.h

@@ -0,0 +1,15 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#ifndef AVALONIA_NATIVE_OSX_INSWINDOWHOLDER_H
+#define AVALONIA_NATIVE_OSX_INSWINDOWHOLDER_H
+
+struct INSWindowHolder
+{
+    virtual AvnWindow* _Nonnull GetNSWindow () = 0;
+    virtual AvnView* _Nonnull GetNSView () = 0;
+};
+
+#endif //AVALONIA_NATIVE_OSX_INSWINDOWHOLDER_H

native/Avalonia.Native/src/OSX/IWindowStateChanged.h

@@ -0,0 +1,18 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#ifndef AVALONIA_NATIVE_OSX_IWINDOWSTATECHANGED_H
+#define AVALONIA_NATIVE_OSX_IWINDOWSTATECHANGED_H
+
+struct IWindowStateChanged
+{
+    virtual void WindowStateChanged () = 0;
+    virtual void StartStateTransition () = 0;
+    virtual void EndStateTransition () = 0;
+    virtual SystemDecorations Decorations () = 0;
+    virtual AvnWindowState WindowState () = 0;
+};
+
+#endif //AVALONIA_NATIVE_OSX_IWINDOWSTATECHANGED_H

native/Avalonia.Native/src/OSX/ResizeScope.h

@@ -0,0 +1,23 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#ifndef AVALONIA_NATIVE_OSX_RESIZESCOPE_H
+#define AVALONIA_NATIVE_OSX_RESIZESCOPE_H
+
+#include "window.h"
+#include "avalonia-native.h"
+
+class ResizeScope
+{
+public:
+    ResizeScope(AvnView* _Nonnull view, AvnPlatformResizeReason reason);
+
+    ~ResizeScope();
+private:
+    AvnView* _Nonnull _view;
+    AvnPlatformResizeReason _restore;
+};
+
+#endif //AVALONIA_NATIVE_OSX_RESIZESCOPE_H

native/Avalonia.Native/src/OSX/ResizeScope.mm

@@ -0,0 +1,17 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#import <AppKit/AppKit.h>
+#include "ResizeScope.h"
+
+ResizeScope::ResizeScope(AvnView *view, AvnPlatformResizeReason reason) {
+    _view = view;
+    _restore = [view getResizeReason];
+    [view setResizeReason:reason];
+}
+
+ResizeScope::~ResizeScope() {
+    [_view setResizeReason:_restore];
+}

native/Avalonia.Native/src/OSX/SystemDialogs.mm

@@ -1,5 +1,6 @@
 #include "common.h"
 #include "window.h"
+#include "INSWindowHolder.h"
 
 class SystemDialogs : public ComSingleObject<IAvnSystemDialogs, &IID_IAvnSystemDialogs>
 {

native/Avalonia.Native/src/OSX/WindowBaseImpl.h

@@ -0,0 +1,119 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#ifndef AVALONIA_NATIVE_OSX_WINDOWBASEIMPL_H
+#define AVALONIA_NATIVE_OSX_WINDOWBASEIMPL_H
+
+#import "rendertarget.h"
+#include "INSWindowHolder.h"
+
+class WindowBaseImpl : public virtual ComObject,
+                       public virtual IAvnWindowBase,
+                       public INSWindowHolder {
+private:
+    NSCursor *cursor;
+
+public:
+    FORWARD_IUNKNOWN()
+
+BEGIN_INTERFACE_MAP()
+        INTERFACE_MAP_ENTRY(IAvnWindowBase, IID_IAvnWindowBase)
+    END_INTERFACE_MAP()
+
+    virtual ~WindowBaseImpl() {
+        View = NULL;
+        Window = NULL;
+    }
+
+    AutoFitContentView *StandardContainer;
+    AvnView *View;
+    AvnWindow *Window;
+    ComPtr<IAvnWindowBaseEvents> BaseEvents;
+    ComPtr<IAvnGlContext> _glContext;
+    NSObject <IRenderTarget> *renderTarget;
+    AvnPoint lastPositionSet;
+    NSString *_lastTitle;
+
+    bool _shown;
+    bool _inResize;
+
+    WindowBaseImpl(IAvnWindowBaseEvents *events, IAvnGlContext *gl);
+
+    virtual HRESULT ObtainNSWindowHandle(void **ret) override;
+
+    virtual HRESULT ObtainNSWindowHandleRetained(void **ret) override;
+
+    virtual HRESULT ObtainNSViewHandle(void **ret) override;
+
+    virtual HRESULT ObtainNSViewHandleRetained(void **ret) override;
+
+    virtual AvnWindow *GetNSWindow() override;
+
+    virtual AvnView *GetNSView() override;
+
+    virtual HRESULT Show(bool activate, bool isDialog) override;
+
+    virtual bool ShouldTakeFocusOnShow();
+
+    virtual HRESULT Hide() override;
+
+    virtual HRESULT Activate() override;
+
+    virtual HRESULT SetTopMost(bool value) override;
+
+    virtual HRESULT Close() override;
+
+    virtual HRESULT GetClientSize(AvnSize *ret) override;
+
+    virtual HRESULT GetFrameSize(AvnSize *ret) override;
+
+    virtual HRESULT GetScaling(double *ret) override;
+
+    virtual HRESULT SetMinMaxSize(AvnSize minSize, AvnSize maxSize) override;
+
+    virtual HRESULT Resize(double x, double y, AvnPlatformResizeReason reason) override;
+
+    virtual HRESULT Invalidate(__attribute__((unused)) AvnRect rect) override;
+
+    virtual HRESULT SetMainMenu(IAvnMenu *menu) override;
+
+    virtual HRESULT BeginMoveDrag() override;
+
+    virtual HRESULT BeginResizeDrag(__attribute__((unused)) AvnWindowEdge edge) override;
+
+    virtual HRESULT GetPosition(AvnPoint *ret) override;
+
+    virtual HRESULT SetPosition(AvnPoint point) override;
+
+    virtual HRESULT PointToClient(AvnPoint point, AvnPoint *ret) override;
+
+    virtual HRESULT PointToScreen(AvnPoint point, AvnPoint *ret) override;
+
+    virtual HRESULT ThreadSafeSetSwRenderedFrame(AvnFramebuffer *fb, IUnknown *dispose) override;
+
+    virtual HRESULT SetCursor(IAvnCursor *cursor) override;
+
+    virtual void UpdateCursor();
+
+    virtual HRESULT CreateGlRenderTarget(IAvnGlSurfaceRenderTarget **ppv) override;
+
+    virtual HRESULT CreateNativeControlHost(IAvnNativeControlHost **retOut) override;
+
+    virtual HRESULT SetBlurEnabled(bool enable) override;
+
+    virtual HRESULT BeginDragAndDropOperation(AvnDragDropEffects effects, AvnPoint point,
+            IAvnClipboard *clipboard, IAvnDndResultCallback *cb,
+            void *sourceHandle) override;
+
+    virtual bool IsDialog();
+
+protected:
+    virtual NSWindowStyleMask GetStyle();
+
+    void UpdateStyle();
+
+};
+
+#endif //AVALONIA_NATIVE_OSX_WINDOWBASEIMPL_H

native/Avalonia.Native/src/OSX/WindowBaseImpl.mm

@@ -0,0 +1,505 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#import <AppKit/AppKit.h>
+#include "common.h"
+#import "window.h"
+#include "menu.h"
+#include "rendertarget.h"
+#include "automation.h"
+#import "WindowBaseImpl.h"
+#import "cursor.h"
+#include "ResizeScope.h"
+
+WindowBaseImpl::WindowBaseImpl(IAvnWindowBaseEvents *events, IAvnGlContext *gl) {
+    _shown = false;
+    _inResize = false;
+    BaseEvents = events;
+    _glContext = gl;
+    renderTarget = [[IOSurfaceRenderTarget alloc] initWithOpenGlContext:gl];
+    View = [[AvnView alloc] initWithParent:this];
+    StandardContainer = [[AutoFitContentView new] initWithContent:View];
+
+    Window = [[AvnWindow alloc] initWithParent:this];
+    [Window setContentView:StandardContainer];
+
+    lastPositionSet.X = 100;
+    lastPositionSet.Y = 100;
+    _lastTitle = @"";
+
+    [Window setStyleMask:NSWindowStyleMaskBorderless];
+    [Window setBackingType:NSBackingStoreBuffered];
+
+    [Window setOpaque:false];
+}
+
+HRESULT WindowBaseImpl::ObtainNSViewHandle(void **ret) {
+    START_COM_CALL;
+
+    if (ret == nullptr) {
+        return E_POINTER;
+    }
+
+    *ret = (__bridge void *) View;
+
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::ObtainNSViewHandleRetained(void **ret) {
+    START_COM_CALL;
+
+    if (ret == nullptr) {
+        return E_POINTER;
+    }
+
+    *ret = (__bridge_retained void *) View;
+
+    return S_OK;
+}
+
+AvnWindow *WindowBaseImpl::GetNSWindow() {
+    return Window;
+}
+
+AvnView *WindowBaseImpl::GetNSView() {
+    return View;
+}
+
+HRESULT WindowBaseImpl::ObtainNSWindowHandleRetained(void **ret) {
+    START_COM_CALL;
+
+    if (ret == nullptr) {
+        return E_POINTER;
+    }
+
+    *ret = (__bridge_retained void *) Window;
+
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::Show(bool activate, bool isDialog) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        SetPosition(lastPositionSet);
+        UpdateStyle();
+
+        [Window setTitle:_lastTitle];
+
+        if (ShouldTakeFocusOnShow() && activate) {
+            [Window orderFront:Window];
+            [Window makeKeyAndOrderFront:Window];
+            [Window makeFirstResponder:View];
+            [NSApp activateIgnoringOtherApps:YES];
+        } else {
+            [Window orderFront:Window];
+        }
+
+        _shown = true;
+
+        return S_OK;
+    }
+}
+
+bool WindowBaseImpl::ShouldTakeFocusOnShow() {
+    return true;
+}
+
+HRESULT WindowBaseImpl::ObtainNSWindowHandle(void **ret) {
+    START_COM_CALL;
+
+    if (ret == nullptr) {
+        return E_POINTER;
+    }
+
+    *ret = (__bridge void *) Window;
+
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::Hide() {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (Window != nullptr) {
+            [Window orderOut:Window];
+            [Window restoreParentWindow];
+        }
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::Activate() {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (Window != nullptr) {
+            [Window makeKeyAndOrderFront:nil];
+            [NSApp activateIgnoringOtherApps:YES];
+        }
+    }
+
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::SetTopMost(bool value) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        [Window setLevel:value ? NSFloatingWindowLevel : NSNormalWindowLevel];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::Close() {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (Window != nullptr) {
+            auto window = Window;
+            Window = nullptr;
+
+            try {
+                // Seems to throw sometimes on application exit.
+                [window close];
+            }
+            catch (NSException *) {}
+        }
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::GetClientSize(AvnSize *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr)
+            return E_POINTER;
+
+        auto frame = [View frame];
+        ret->Width = frame.size.width;
+        ret->Height = frame.size.height;
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::GetFrameSize(AvnSize *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr)
+            return E_POINTER;
+
+        auto frame = [Window frame];
+        ret->Width = frame.size.width;
+        ret->Height = frame.size.height;
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::GetScaling(double *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr)
+            return E_POINTER;
+
+        if (Window == nullptr) {
+            *ret = 1;
+            return S_OK;
+        }
+
+        *ret = [Window backingScaleFactor];
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::SetMinMaxSize(AvnSize minSize, AvnSize maxSize) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        [Window setMinSize:ToNSSize(minSize)];
+        [Window setMaxSize:ToNSSize(maxSize)];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::Resize(double x, double y, AvnPlatformResizeReason reason) {
+    if (_inResize) {
+        return S_OK;
+    }
+
+    _inResize = true;
+
+    START_COM_CALL;
+    auto resizeBlock = ResizeScope(View, reason);
+
+    @autoreleasepool {
+        auto maxSize = [Window maxSize];
+        auto minSize = [Window minSize];
+
+        if (x < minSize.width) {
+            x = minSize.width;
+        }
+
+        if (y < minSize.height) {
+            y = minSize.height;
+        }
+
+        if (x > maxSize.width) {
+            x = maxSize.width;
+        }
+
+        if (y > maxSize.height) {
+            y = maxSize.height;
+        }
+
+        @try {
+            if (!_shown) {
+                BaseEvents->Resized(AvnSize{x, y}, reason);
+            }
+
+            [Window setContentSize:NSSize{x, y}];
+            [Window invalidateShadow];
+        }
+        @finally {
+            _inResize = false;
+        }
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::Invalidate(__attribute__((unused)) AvnRect rect) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        [View setNeedsDisplayInRect:[View frame]];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::SetMainMenu(IAvnMenu *menu) {
+    START_COM_CALL;
+
+    auto nativeMenu = dynamic_cast<AvnAppMenu *>(menu);
+
+    auto nsmenu = nativeMenu->GetNative();
+
+    [Window applyMenu:nsmenu];
+
+    if ([Window isKeyWindow]) {
+        [Window showWindowMenuWithAppMenu];
+    }
+
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::BeginMoveDrag() {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        auto lastEvent = [View lastMouseDownEvent];
+
+        if (lastEvent == nullptr) {
+            return S_OK;
+        }
+
+        [Window performWindowDragWithEvent:lastEvent];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::BeginResizeDrag(__attribute__((unused)) AvnWindowEdge edge) {
+    START_COM_CALL;
+
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::GetPosition(AvnPoint *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr) {
+            return E_POINTER;
+        }
+
+        auto frame = [Window frame];
+
+        ret->X = frame.origin.x;
+        ret->Y = frame.origin.y + frame.size.height;
+
+        *ret = ConvertPointY(*ret);
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::SetPosition(AvnPoint point) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        lastPositionSet = point;
+        [Window setFrameTopLeftPoint:ToNSPoint(ConvertPointY(point))];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::PointToClient(AvnPoint point, AvnPoint *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr) {
+            return E_POINTER;
+        }
+
+        point = ConvertPointY(point);
+        NSRect convertRect = [Window convertRectFromScreen:NSMakeRect(point.X, point.Y, 0.0, 0.0)];
+        auto viewPoint = NSMakePoint(convertRect.origin.x, convertRect.origin.y);
+
+        *ret = [View translateLocalPoint:ToAvnPoint(viewPoint)];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::PointToScreen(AvnPoint point, AvnPoint *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr) {
+            return E_POINTER;
+        }
+
+        auto cocoaViewPoint = ToNSPoint([View translateLocalPoint:point]);
+        NSRect convertRect = [Window convertRectToScreen:NSMakeRect(cocoaViewPoint.x, cocoaViewPoint.y, 0.0, 0.0)];
+        auto cocoaScreenPoint = NSPointFromCGPoint(NSMakePoint(convertRect.origin.x, convertRect.origin.y));
+        *ret = ConvertPointY(ToAvnPoint(cocoaScreenPoint));
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowBaseImpl::ThreadSafeSetSwRenderedFrame(AvnFramebuffer *fb, IUnknown *dispose) {
+    START_COM_CALL;
+
+    [View setSwRenderedFrame:fb dispose:dispose];
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::SetCursor(IAvnCursor *cursor) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        Cursor *avnCursor = dynamic_cast<Cursor *>(cursor);
+        this->cursor = avnCursor->GetNative();
+        UpdateCursor();
+
+        if (avnCursor->IsHidden()) {
+            [NSCursor hide];
+        } else {
+            [NSCursor unhide];
+        }
+
+        return S_OK;
+    }
+}
+
+void WindowBaseImpl::UpdateCursor() {
+    if (cursor != nil) {
+        [cursor set];
+    }
+}
+
+HRESULT WindowBaseImpl::CreateGlRenderTarget(IAvnGlSurfaceRenderTarget **ppv) {
+    START_COM_CALL;
+
+    if (View == NULL)
+        return E_FAIL;
+    *ppv = [renderTarget createSurfaceRenderTarget];
+    return static_cast<HRESULT>(*ppv == nil ? E_FAIL : S_OK);
+}
+
+HRESULT WindowBaseImpl::CreateNativeControlHost(IAvnNativeControlHost **retOut) {
+    START_COM_CALL;
+
+    if (View == NULL)
+        return E_FAIL;
+    *retOut = ::CreateNativeControlHost(View);
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::SetBlurEnabled(bool enable) {
+    START_COM_CALL;
+
+    [StandardContainer ShowBlur:enable];
+
+    return S_OK;
+}
+
+HRESULT WindowBaseImpl::BeginDragAndDropOperation(AvnDragDropEffects effects, AvnPoint point, IAvnClipboard *clipboard, IAvnDndResultCallback *cb, void *sourceHandle) {
+    START_COM_CALL;
+
+    auto item = TryGetPasteboardItem(clipboard);
+    [item setString:@"" forType:GetAvnCustomDataType()];
+    if (item == nil)
+        return E_INVALIDARG;
+    if (View == NULL)
+        return E_FAIL;
+
+    auto nsevent = [NSApp currentEvent];
+    auto nseventType = [nsevent type];
+
+    // If current event isn't a mouse one (probably due to malfunctioning user app)
+    // attempt to forge a new one
+    if (!((nseventType >= NSEventTypeLeftMouseDown && nseventType <= NSEventTypeMouseExited)
+            || (nseventType >= NSEventTypeOtherMouseDown && nseventType <= NSEventTypeOtherMouseDragged))) {
+        NSRect convertRect = [Window convertRectToScreen:NSMakeRect(point.X, point.Y, 0.0, 0.0)];
+        auto nspoint = NSMakePoint(convertRect.origin.x, convertRect.origin.y);
+        CGPoint cgpoint = NSPointToCGPoint(nspoint);
+        auto cgevent = CGEventCreateMouseEvent(NULL, kCGEventLeftMouseDown, cgpoint, kCGMouseButtonLeft);
+        nsevent = [NSEvent eventWithCGEvent:cgevent];
+        CFRelease(cgevent);
+    }
+
+    auto dragItem = [[NSDraggingItem alloc] initWithPasteboardWriter:item];
+
+    auto dragItemImage = [NSImage imageNamed:NSImageNameMultipleDocuments];
+    NSRect dragItemRect = {(float) point.X, (float) point.Y, [dragItemImage size].width, [dragItemImage size].height};
+    [dragItem setDraggingFrame:dragItemRect contents:dragItemImage];
+
+    int op = 0;
+    int ieffects = (int) effects;
+    if ((ieffects & (int) AvnDragDropEffects::Copy) != 0)
+        op |= NSDragOperationCopy;
+    if ((ieffects & (int) AvnDragDropEffects::Link) != 0)
+        op |= NSDragOperationLink;
+    if ((ieffects & (int) AvnDragDropEffects::Move) != 0)
+        op |= NSDragOperationMove;
+    [View beginDraggingSessionWithItems:@[dragItem] event:nsevent
+                                 source:CreateDraggingSource((NSDragOperation) op, cb, sourceHandle)];
+    return S_OK;
+}
+
+bool WindowBaseImpl::IsDialog() {
+    return false;
+}
+
+NSWindowStyleMask WindowBaseImpl::GetStyle() {
+    return NSWindowStyleMaskBorderless;
+}
+
+void WindowBaseImpl::UpdateStyle() {
+    [Window setStyleMask:GetStyle()];
+}

native/Avalonia.Native/src/OSX/WindowImpl.h

@@ -0,0 +1,97 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#ifndef AVALONIA_NATIVE_OSX_WINDOWIMPL_H
+#define AVALONIA_NATIVE_OSX_WINDOWIMPL_H
+
+
+#import "WindowBaseImpl.h"
+#include "IWindowStateChanged.h"
+
+class WindowImpl : public virtual WindowBaseImpl, public virtual IAvnWindow, public IWindowStateChanged
+{
+private:
+    bool _canResize;
+    bool _fullScreenActive;
+    SystemDecorations _decorations;
+    AvnWindowState _lastWindowState;
+    AvnWindowState _actualWindowState;
+    bool _inSetWindowState;
+    NSRect _preZoomSize;
+    bool _transitioningWindowState;
+    bool _isClientAreaExtended;
+    bool _isDialog;
+    AvnExtendClientAreaChromeHints _extendClientHints;
+
+    FORWARD_IUNKNOWN()
+BEGIN_INTERFACE_MAP()
+        INHERIT_INTERFACE_MAP(WindowBaseImpl)
+        INTERFACE_MAP_ENTRY(IAvnWindow, IID_IAvnWindow)
+    END_INTERFACE_MAP()
+    virtual ~WindowImpl()
+    {
+    }
+
+    ComPtr<IAvnWindowEvents> WindowEvents;
+
+    WindowImpl(IAvnWindowEvents* events, IAvnGlContext* gl);
+
+    void HideOrShowTrafficLights ();
+
+    virtual HRESULT Show (bool activate, bool isDialog) override;
+
+    virtual HRESULT SetEnabled (bool enable) override;
+
+    virtual HRESULT SetParent (IAvnWindow* parent) override;
+
+    void StartStateTransition () override ;
+
+    void EndStateTransition () override ;
+
+    SystemDecorations Decorations () override ;
+
+    AvnWindowState WindowState () override ;
+
+    void WindowStateChanged () override ;
+
+    bool UndecoratedIsMaximized ();
+
+    bool IsZoomed ();
+
+    void DoZoom();
+
+    virtual HRESULT SetCanResize(bool value) override;
+
+    virtual HRESULT SetDecorations(SystemDecorations value) override;
+
+    virtual HRESULT SetTitle (char* utf8title) override;
+
+    virtual HRESULT SetTitleBarColor(AvnColor color) override;
+
+    virtual HRESULT GetWindowState (AvnWindowState*ret) override;
+
+    virtual HRESULT TakeFocusFromChildren () override;
+
+    virtual HRESULT SetExtendClientArea (bool enable) override;
+
+    virtual HRESULT SetExtendClientAreaHints (AvnExtendClientAreaChromeHints hints) override;
+
+    virtual HRESULT GetExtendTitleBarHeight (double*ret) override;
+
+    virtual HRESULT SetExtendTitleBarHeight (double value) override;
+
+    void EnterFullScreenMode ();
+
+    void ExitFullScreenMode ();
+
+    virtual HRESULT SetWindowState (AvnWindowState state) override;
+
+    virtual bool IsDialog() override;
+
+protected:
+    virtual NSWindowStyleMask GetStyle() override;
+};
+
+#endif //AVALONIA_NATIVE_OSX_WINDOWIMPL_H

native/Avalonia.Native/src/OSX/WindowImpl.mm

@@ -0,0 +1,540 @@
+//
+// Created by Dan Walmsley on 04/05/2022.
+// Copyright (c) 2022 Avalonia. All rights reserved.
+//
+
+#import <AppKit/AppKit.h>
+#import "window.h"
+#include "automation.h"
+#include "menu.h"
+#import "WindowImpl.h"
+
+
+WindowImpl::WindowImpl(IAvnWindowEvents *events, IAvnGlContext *gl) : WindowBaseImpl(events, gl) {
+    _isClientAreaExtended = false;
+    _extendClientHints = AvnDefaultChrome;
+    _fullScreenActive = false;
+    _canResize = true;
+    _decorations = SystemDecorationsFull;
+    _transitioningWindowState = false;
+    _inSetWindowState = false;
+    _lastWindowState = Normal;
+    _actualWindowState = Normal;
+    WindowEvents = events;
+    [Window setCanBecomeKeyAndMain];
+    [Window disableCursorRects];
+    [Window setTabbingMode:NSWindowTabbingModeDisallowed];
+    [Window setCollectionBehavior:NSWindowCollectionBehaviorFullScreenPrimary];
+}
+
+void WindowImpl::HideOrShowTrafficLights() {
+    if (Window == nil) {
+        return;
+    }
+
+    for (id subview in Window.contentView.superview.subviews) {
+        if ([subview isKindOfClass:NSClassFromString(@"NSTitlebarContainerView")]) {
+            NSView *titlebarView = [subview subviews][0];
+            for (id button in titlebarView.subviews) {
+                if ([button isKindOfClass:[NSButton class]]) {
+                    if (_isClientAreaExtended) {
+                        auto wantsChrome = (_extendClientHints & AvnSystemChrome) || (_extendClientHints & AvnPreferSystemChrome);
+
+                        [button setHidden:!wantsChrome];
+                    } else {
+                        [button setHidden:(_decorations != SystemDecorationsFull)];
+                    }
+
+                    [button setWantsLayer:true];
+                }
+            }
+        }
+    }
+}
+
+HRESULT WindowImpl::Show(bool activate, bool isDialog) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        _isDialog = isDialog;
+        WindowBaseImpl::Show(activate, isDialog);
+
+        HideOrShowTrafficLights();
+
+        return SetWindowState(_lastWindowState);
+    }
+}
+
+HRESULT WindowImpl::SetEnabled(bool enable) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        [Window setEnabled:enable];
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::SetParent(IAvnWindow *parent) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (parent == nullptr)
+            return E_POINTER;
+
+        auto cparent = dynamic_cast<WindowImpl *>(parent);
+        if (cparent == nullptr)
+            return E_INVALIDARG;
+
+        // If one tries to show a child window with a minimized parent window, then the parent window will be
+        // restored but macOS isn't kind enough to *tell* us that, so the window will be left in a non-interactive
+        // state. Detect this and explicitly restore the parent window ourselves to avoid this situation.
+        if (cparent->WindowState() == Minimized)
+            cparent->SetWindowState(Normal);
+
+        [Window setCollectionBehavior:NSWindowCollectionBehaviorFullScreenAuxiliary];
+        [cparent->Window addChildWindow:Window ordered:NSWindowAbove];
+
+        UpdateStyle();
+
+        return S_OK;
+    }
+}
+
+void WindowImpl::StartStateTransition() {
+    _transitioningWindowState = true;
+}
+
+void WindowImpl::EndStateTransition() {
+    _transitioningWindowState = false;
+}
+
+SystemDecorations WindowImpl::Decorations() {
+    return _decorations;
+}
+
+AvnWindowState WindowImpl::WindowState() {
+    return _lastWindowState;
+}
+
+void WindowImpl::WindowStateChanged() {
+    if (_shown && !_inSetWindowState && !_transitioningWindowState) {
+        AvnWindowState state;
+        GetWindowState(&state);
+
+        if (_lastWindowState != state) {
+            if (_isClientAreaExtended) {
+                if (_lastWindowState == FullScreen) {
+                    // we exited fs.
+                    if (_extendClientHints & AvnOSXThickTitleBar) {
+                        Window.toolbar = [NSToolbar new];
+                        Window.toolbar.showsBaselineSeparator = false;
+                    }
+
+                    [Window setTitlebarAppearsTransparent:true];
+
+                    [StandardContainer setFrameSize:StandardContainer.frame.size];
+                } else if (state == FullScreen) {
+                    // we entered fs.
+                    if (_extendClientHints & AvnOSXThickTitleBar) {
+                        Window.toolbar = nullptr;
+                    }
+
+                    [Window setTitlebarAppearsTransparent:false];
+
+                    [StandardContainer setFrameSize:StandardContainer.frame.size];
+                }
+            }
+
+            _lastWindowState = state;
+            _actualWindowState = state;
+            WindowEvents->WindowStateChanged(state);
+        }
+    }
+}
+
+bool WindowImpl::UndecoratedIsMaximized() {
+    auto windowSize = [Window frame];
+    auto available = [Window screen].visibleFrame;
+    return CGRectEqualToRect(windowSize, available);
+}
+
+bool WindowImpl::IsZoomed() {
+    return _decorations == SystemDecorationsFull ? [Window isZoomed] : UndecoratedIsMaximized();
+}
+
+void WindowImpl::DoZoom() {
+    switch (_decorations) {
+        case SystemDecorationsNone:
+        case SystemDecorationsBorderOnly:
+            [Window setFrame:[Window screen].visibleFrame display:true];
+            break;
+
+
+        case SystemDecorationsFull:
+            [Window performZoom:Window];
+            break;
+    }
+}
+
+HRESULT WindowImpl::SetCanResize(bool value) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        _canResize = value;
+        UpdateStyle();
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::SetDecorations(SystemDecorations value) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        auto currentWindowState = _lastWindowState;
+        _decorations = value;
+
+        if (_fullScreenActive) {
+            return S_OK;
+        }
+
+        UpdateStyle();
+
+        HideOrShowTrafficLights();
+
+        switch (_decorations) {
+            case SystemDecorationsNone:
+                [Window setHasShadow:NO];
+                [Window setTitleVisibility:NSWindowTitleHidden];
+                [Window setTitlebarAppearsTransparent:YES];
+
+                if (currentWindowState == Maximized) {
+                    if (!UndecoratedIsMaximized()) {
+                        DoZoom();
+                    }
+                }
+                break;
+
+            case SystemDecorationsBorderOnly:
+                [Window setHasShadow:YES];
+                [Window setTitleVisibility:NSWindowTitleHidden];
+                [Window setTitlebarAppearsTransparent:YES];
+
+                if (currentWindowState == Maximized) {
+                    if (!UndecoratedIsMaximized()) {
+                        DoZoom();
+                    }
+                }
+                break;
+
+            case SystemDecorationsFull:
+                [Window setHasShadow:YES];
+                [Window setTitleVisibility:NSWindowTitleVisible];
+                [Window setTitlebarAppearsTransparent:NO];
+                [Window setTitle:_lastTitle];
+
+                if (currentWindowState == Maximized) {
+                    auto newFrame = [Window contentRectForFrameRect:[Window frame]].size;
+
+                    [View setFrameSize:newFrame];
+                }
+                break;
+        }
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::SetTitle(char *utf8title) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        _lastTitle = [NSString stringWithUTF8String:(const char *) utf8title];
+        [Window setTitle:_lastTitle];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::SetTitleBarColor(AvnColor color) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        float a = (float) color.Alpha / 255.0f;
+        float r = (float) color.Red / 255.0f;
+        float g = (float) color.Green / 255.0f;
+        float b = (float) color.Blue / 255.0f;
+
+        auto nscolor = [NSColor colorWithSRGBRed:r green:g blue:b alpha:a];
+
+        // Based on the titlebar color we have to choose either light or dark
+        // OSX doesnt let you set a foreground color for titlebar.
+        if ((r * 0.299 + g * 0.587 + b * 0.114) > 186.0f / 255.0f) {
+            [Window setAppearance:[NSAppearance appearanceNamed:NSAppearanceNameVibrantLight]];
+        } else {
+            [Window setAppearance:[NSAppearance appearanceNamed:NSAppearanceNameVibrantDark]];
+        }
+
+        [Window setTitlebarAppearsTransparent:true];
+        [Window setBackgroundColor:nscolor];
+    }
+
+    return S_OK;
+}
+
+HRESULT WindowImpl::GetWindowState(AvnWindowState *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr) {
+            return E_POINTER;
+        }
+
+        if (([Window styleMask] & NSWindowStyleMaskFullScreen) == NSWindowStyleMaskFullScreen) {
+            *ret = FullScreen;
+            return S_OK;
+        }
+
+        if ([Window isMiniaturized]) {
+            *ret = Minimized;
+            return S_OK;
+        }
+
+        if (IsZoomed()) {
+            *ret = Maximized;
+            return S_OK;
+        }
+
+        *ret = Normal;
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::TakeFocusFromChildren() {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (Window == nil)
+            return S_OK;
+        if ([Window isKeyWindow])
+            [Window makeFirstResponder:View];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::SetExtendClientArea(bool enable) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        _isClientAreaExtended = enable;
+
+        if (enable) {
+            Window.titleVisibility = NSWindowTitleHidden;
+
+            [Window setTitlebarAppearsTransparent:true];
+
+            auto wantsTitleBar = (_extendClientHints & AvnSystemChrome) || (_extendClientHints & AvnPreferSystemChrome);
+
+            if (wantsTitleBar) {
+                [StandardContainer ShowTitleBar:true];
+            } else {
+                [StandardContainer ShowTitleBar:false];
+            }
+
+            if (_extendClientHints & AvnOSXThickTitleBar) {
+                Window.toolbar = [NSToolbar new];
+                Window.toolbar.showsBaselineSeparator = false;
+            } else {
+                Window.toolbar = nullptr;
+            }
+        } else {
+            Window.titleVisibility = NSWindowTitleVisible;
+            Window.toolbar = nullptr;
+            [Window setTitlebarAppearsTransparent:false];
+            View.layer.zPosition = 0;
+        }
+
+        [Window setIsExtended:enable];
+
+        HideOrShowTrafficLights();
+
+        UpdateStyle();
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::SetExtendClientAreaHints(AvnExtendClientAreaChromeHints hints) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        _extendClientHints = hints;
+
+        SetExtendClientArea(_isClientAreaExtended);
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::GetExtendTitleBarHeight(double *ret) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (ret == nullptr) {
+            return E_POINTER;
+        }
+
+        *ret = [Window getExtendedTitleBarHeight];
+
+        return S_OK;
+    }
+}
+
+HRESULT WindowImpl::SetExtendTitleBarHeight(double value) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        [StandardContainer SetTitleBarHeightHint:value];
+        return S_OK;
+    }
+}
+
+void WindowImpl::EnterFullScreenMode() {
+    _fullScreenActive = true;
+
+    [Window setTitle:_lastTitle];
+    [Window toggleFullScreen:nullptr];
+}
+
+void WindowImpl::ExitFullScreenMode() {
+    [Window toggleFullScreen:nullptr];
+
+    _fullScreenActive = false;
+
+    SetDecorations(_decorations);
+}
+
+HRESULT WindowImpl::SetWindowState(AvnWindowState state) {
+    START_COM_CALL;
+
+    @autoreleasepool {
+        if (Window == nullptr) {
+            return S_OK;
+        }
+
+        if (_actualWindowState == state) {
+            return S_OK;
+        }
+
+        _inSetWindowState = true;
+
+        auto currentState = _actualWindowState;
+        _lastWindowState = state;
+
+        if (currentState == Normal) {
+            _preZoomSize = [Window frame];
+        }
+
+        if (_shown) {
+            switch (state) {
+                case Maximized:
+                    if (currentState == FullScreen) {
+                        ExitFullScreenMode();
+                    }
+
+                    lastPositionSet.X = 0;
+                    lastPositionSet.Y = 0;
+
+                    if ([Window isMiniaturized]) {
+                        [Window deminiaturize:Window];
+                    }
+
+                    if (!IsZoomed()) {
+                        DoZoom();
+                    }
+                    break;
+
+                case Minimized:
+                    if (currentState == FullScreen) {
+                        ExitFullScreenMode();
+                    } else {
+                        [Window miniaturize:Window];
+                    }
+                    break;
+
+                case FullScreen:
+                    if ([Window isMiniaturized]) {
+                        [Window deminiaturize:Window];
+                    }
+
+                    EnterFullScreenMode();
+                    break;
+
+                case Normal:
+                    if ([Window isMiniaturized]) {
+                        [Window deminiaturize:Window];
+                    }
+
+                    if (currentState == FullScreen) {
+                        ExitFullScreenMode();
+                    }
+
+                    if (IsZoomed()) {
+                        if (_decorations == SystemDecorationsFull) {
+                            DoZoom();
+                        } else {
+                            [Window setFrame:_preZoomSize display:true];
+                            auto newFrame = [Window contentRectForFrameRect:[Window frame]].size;
+
+                            [View setFrameSize:newFrame];
+                        }
+
+                    }
+                    break;
+            }
+
+            _actualWindowState = _lastWindowState;
+            WindowEvents->WindowStateChanged(_actualWindowState);
+        }
+
+
+        _inSetWindowState = false;
+
+        return S_OK;
+    }
+}
+
+bool WindowImpl::IsDialog() {
+    return _isDialog;
+}
+
+NSWindowStyleMask WindowImpl::GetStyle() {
+    unsigned long s = NSWindowStyleMaskBorderless;
+
+    switch (_decorations) {
+        case SystemDecorationsNone:
+            s = s | NSWindowStyleMaskFullSizeContentView;
+            break;
+
+        case SystemDecorationsBorderOnly:
+            s = s | NSWindowStyleMaskTitled | NSWindowStyleMaskFullSizeContentView;
+            break;
+
+        case SystemDecorationsFull:
+            s = s | NSWindowStyleMaskTitled | NSWindowStyleMaskClosable | NSWindowStyleMaskBorderless;
+
+            if (_canResize) {
+                s = s | NSWindowStyleMaskResizable;
+            }
+            break;
+    }
+
+    if ([Window parentWindow] == nullptr) {
+        s |= NSWindowStyleMaskMiniaturizable;
+    }
+
+    if (_isClientAreaExtended) {
+        s |= NSWindowStyleMaskFullSizeContentView | NSWindowStyleMaskTexturedBackground;
+    }
+    return s;
+}

native/Avalonia.Native/src/OSX/app.mm

@@ -82,18 +82,6 @@ ComPtr<IAvnApplicationEvents> _events;
         _isHandlingSendEvent = oldHandling;
     }
 }
-
-// This is needed for certain embedded controls
-- (BOOL) isHandlingSendEvent
-{
-    return _isHandlingSendEvent;
-}
-
-- (void)setHandlingSendEvent:(BOOL)handlingSendEvent
-{
-    _isHandlingSendEvent = handlingSendEvent;
-}
-
 @end
 
 extern void InitializeAvnApp(IAvnApplicationEvents* events)

native/Avalonia.Native/src/OSX/automation.h

@@ -1,5 +1,4 @@
 #import <Cocoa/Cocoa.h>
-#include "window.h"
 
 NS_ASSUME_NONNULL_BEGIN
 

native/Avalonia.Native/src/OSX/automation.mm

@@ -1,7 +1,8 @@
 #include "common.h"
-#include "automation.h"
+#import "automation.h"
+#import "window.h"
 #include "AvnString.h"
-#include "window.h"
+#import "INSWindowHolder.h"
 
 @interface AvnAccessibilityElement (Events)
 - (void) raiseChildrenChanged;

native/Avalonia.Native/src/OSX/common.h

@@ -27,7 +27,7 @@ extern IAvnMenuItem* CreateAppMenuItem();
 extern IAvnMenuItem* CreateAppMenuItemSeparator();
 extern IAvnApplicationCommands* CreateApplicationCommands();
 extern IAvnNativeControlHost* CreateNativeControlHost(NSView* parent);
-extern void SetAppMenu (NSString* appName, IAvnMenu* appMenu);
+extern void SetAppMenu(IAvnMenu *menu);
 extern void SetServicesMenu (IAvnMenu* menu);
 extern IAvnMenu* GetAppMenu ();
 extern NSMenuItem* GetAppMenuItem ();
@@ -38,7 +38,6 @@ extern NSPoint ToNSPoint (AvnPoint p);
 extern NSRect ToNSRect (AvnRect r);
 extern AvnPoint ToAvnPoint (NSPoint p);
 extern AvnPoint ConvertPointY (AvnPoint p);
-extern CGFloat PrimaryDisplayHeight();
 extern NSSize ToNSSize (AvnSize s);
 #ifdef DEBUG
 #define NSDebugLog(...) NSLog(__VA_ARGS__)

native/Avalonia.Native/src/OSX/cursor.mm

@@ -1,6 +1,5 @@
 #include "common.h"
 #include "cursor.h"
-#include <map>
 
 class CursorFactory : public ComSingleObject<IAvnCursorFactory, &IID_IAvnCursorFactory>
 {

native/Avalonia.Native/src/OSX/main.mm

@@ -343,7 +343,7 @@ public:
         
         @autoreleasepool
         {
-            ::SetAppMenu(s_appTitle, appMenu);
+            ::SetAppMenu(appMenu);
             return S_OK;
         }
     }
@@ -428,7 +428,3 @@ AvnPoint ConvertPointY (AvnPoint p)
     return p;
 }
 
-CGFloat PrimaryDisplayHeight()
-{
-  return NSMaxY([[[NSScreen screens] firstObject] frame]);
-}

native/Avalonia.Native/src/OSX/menu.h

@@ -31,7 +31,6 @@ private:
     NSMenuItem* _native; // here we hold a pointer to an AvnMenuItem
     IAvnActionCallback* _callback;
     IAvnPredicateCallback* _predicate;
-    bool _isSeparator;
     bool _isCheckable;
     
 public:

native/Avalonia.Native/src/OSX/menu.mm

@@ -1,7 +1,7 @@
 
 #include "common.h"
 #include "menu.h"
-#include "window.h"
+#import "window.h"
 #include "KeyTransform.h"
 #include <CoreFoundation/CoreFoundation.h>
 #include <Carbon/Carbon.h> /* For kVK_ constants, and TIS functions. */
@@ -74,8 +74,7 @@
 AvnAppMenuItem::AvnAppMenuItem(bool isSeparator)
 {
     _isCheckable = false;
-    _isSeparator = isSeparator;
-    
+
     if(isSeparator)
     {
         _native = [NSMenuItem separatorItem];
@@ -460,7 +459,7 @@ extern IAvnMenuItem* CreateAppMenuItemSeparator()
 static IAvnMenu* s_appMenu = nullptr;
 static NSMenuItem* s_appMenuItem = nullptr;
 
-extern void SetAppMenu (NSString* appName, IAvnMenu* menu)
+extern void SetAppMenu(IAvnMenu *menu)
 {
     s_appMenu = menu;
     

native/Avalonia.Native/src/OSX/rendertarget.mm

@@ -1,14 +1,10 @@
 #include "common.h"
 #include "rendertarget.h"
-#import <IOSurface/IOSurface.h>
 #import <IOSurface/IOSurfaceObjC.h>
 #import <QuartzCore/QuartzCore.h>
 
-#include <OpenGL/CGLIOSurface.h>
-#include <OpenGL/OpenGL.h>
 #include <OpenGL/glext.h>
 #include <OpenGL/gl3.h>
-#include <OpenGL/gl3ext.h>
 
 @interface IOSurfaceHolder : NSObject
 @end

native/Avalonia.Native/src/OSX/window.h

@@ -1,6 +1,10 @@
 #ifndef window_h
 #define window_h
 
+#import "avalonia-native.h"
+
+@class AvnMenu;
+
 class WindowBaseImpl;
 
 @interface AvnView : NSView<NSTextInputClient, NSDraggingDestination>
@@ -9,7 +13,7 @@ class WindowBaseImpl;
 -(AvnPoint) translateLocalPoint:(AvnPoint)pt;
 -(void) setSwRenderedFrame: (AvnFramebuffer* _Nonnull) fb dispose: (IUnknown* _Nonnull) dispose;
 -(void) onClosed;
--(AvnPixelSize) getPixelSize;
+
 -(AvnPlatformResizeReason) getResizeReason;
 -(void) setResizeReason:(AvnPlatformResizeReason)reason;
 + (AvnPoint)toAvnPoint:(CGPoint)p;
@@ -19,12 +23,11 @@ class WindowBaseImpl;
 -(AutoFitContentView* _Nonnull) initWithContent: (NSView* _Nonnull) content;
 -(void) ShowTitleBar: (bool) show;
 -(void) SetTitleBarHeightHint: (double) height;
--(void) SetContent: (NSView* _Nonnull) content;
+
 -(void) ShowBlur: (bool) show;
 @end
 
 @interface AvnWindow : NSWindow <NSWindowDelegate>
-+(void) closeAll;
 -(AvnWindow* _Nonnull) initWithParent: (WindowBaseImpl* _Nonnull) parent;
 -(void) setCanBecomeKeyAndMain;
 -(void) pollModalSession: (NSModalSession _Nonnull) session;
@@ -33,45 +36,11 @@ class WindowBaseImpl;
 -(void) setEnabled: (bool) enable;
 -(void) showAppMenuOnly;
 -(void) showWindowMenuWithAppMenu;
--(void) applyMenu:(NSMenu* _Nullable)menu;
--(double) getScaling;
+-(void) applyMenu:(AvnMenu* _Nullable)menu;
+
 -(double) getExtendedTitleBarHeight;
 -(void) setIsExtended:(bool)value;
 -(bool) isDialog;
 @end
 
-struct INSWindowHolder
-{
-    virtual AvnWindow* _Nonnull GetNSWindow () = 0;
-    virtual AvnView* _Nonnull GetNSView () = 0;
-};
-
-struct IWindowStateChanged
-{
-    virtual void WindowStateChanged () = 0;
-    virtual void StartStateTransition () = 0;
-    virtual void EndStateTransition () = 0;
-    virtual SystemDecorations Decorations () = 0;
-    virtual AvnWindowState WindowState () = 0;
-};
-
-class ResizeScope
-{
-public:
-    ResizeScope(AvnView* _Nonnull view, AvnPlatformResizeReason reason)
-    {
-        _view = view;
-        _restore = [view getResizeReason];
-        [view setResizeReason:reason];
-    }
-    
-    ~ResizeScope()
-    {
-        [_view setResizeReason:_restore];
-    }
-private:
-    AvnView* _Nonnull _view;
-    AvnPlatformResizeReason _restore;
-};
-
 #endif /* window_h */

samples/ControlCatalog/App.xaml.cs

@@ -20,12 +20,12 @@ namespace ControlCatalog
 
         public static readonly StyleInclude ColorPickerFluent = new StyleInclude(new Uri("avares://ControlCatalog/Styles"))
         {
-            Source = new Uri("avares://Avalonia.Controls.ColorPicker/Themes/Fluent.xaml")
+            Source = new Uri("avares://Avalonia.Controls.ColorPicker/Themes/Fluent/Fluent.xaml")
         };
 
         public static readonly StyleInclude ColorPickerDefault = new StyleInclude(new Uri("avares://ControlCatalog/Styles"))
         {
-            Source = new Uri("avares://Avalonia.Controls.ColorPicker/Themes/Default.xaml")
+            Source = new Uri("avares://Avalonia.Controls.ColorPicker/Themes/Default/Default.xaml")
         };
 
         public static readonly StyleInclude DataGridFluent = new StyleInclude(new Uri("avares://ControlCatalog/Styles"))

samples/ControlCatalog/Pages/ColorPickerPage.xaml

@@ -3,27 +3,77 @@
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:primitives="clr-namespace:Avalonia.Controls.Primitives;assembly=Avalonia.Controls"
-             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+             xmlns:pc="clr-namespace:Avalonia.Controls.Primitives.Converters;assembly=Avalonia.Controls.ColorPicker"
+             mc:Ignorable="d"
+             d:DesignWidth="800"
+             d:DesignHeight="450"
              x:Class="ControlCatalog.Pages.ColorPickerPage">
 
-  <Grid ColumnDefinitions="Auto,Auto"
-        RowDefinitions="Auto,Auto">
-    <ColorSpectrum Grid.Column="0"
+  <UserControl.Resources>
+    <pc:ThirdComponentConverter x:Key="ThirdComponent" />
+  </UserControl.Resources>
+
+  <Grid ColumnDefinitions="Auto,10,Auto">
+    <Grid Grid.Column="0"
+          Grid.Row="0"
+          RowDefinitions="Auto,Auto,Auto,Auto,Auto,Auto">
+      <ColorSpectrum x:Name="ColorSpectrum1"
+                     Grid.Row="0"
+                     Color="Red"
+                     CornerRadius="10"
+                     Height="256"
+                     Width="256" />
+      <ColorSlider Grid.Row="1"
+                   Margin="0,10,0,0"
+                   ColorComponent="Component1"
+                   ColorModel="Hsva"
+                   HsvColor="{Binding HsvColor, ElementName=ColorSpectrum1}" />
+      <ColorSlider Grid.Row="2"
+                   ColorComponent="Component2"
+                   ColorModel="Hsva"
+                   HsvColor="{Binding HsvColor, ElementName=ColorSpectrum1}" />
+      <ColorSlider Grid.Row="3"
+                   ColorComponent="Component3"
+                   ColorModel="Hsva"
+                   HsvColor="{Binding HsvColor, ElementName=ColorSpectrum1}" />
+      <ColorSlider Grid.Row="4"
+                   ColorComponent="Alpha"
+                   ColorModel="Hsva"
+                   HsvColor="{Binding HsvColor, ElementName=ColorSpectrum1}" />
+      <ColorPreviewer Grid.Row="5"
+                      ShowAccentColors="True"
+                      HsvColor="{Binding HsvColor, ElementName=ColorSpectrum1}" />
+    </Grid>
+    <Grid Grid.Column="2"
+          Grid.Row="0"
+          ColumnDefinitions="Auto,Auto,Auto"
+          RowDefinitions="Auto,Auto">
+      <ColorSlider Grid.Column="0"
                    Grid.Row="0"
-                   Color="Red"
-                   Height="256"
-                   Width="256" />
-    <ColorSpectrum Grid.Column="1"
+                   IsAlphaMaxForced="True"
+                   IsSaturationValueMaxForced="False"
+                   ColorComponent="{Binding Components, ElementName=ColorSpectrum2, Converter={StaticResource ThirdComponent}}"
+                   ColorModel="Hsva"
+                   Orientation="Vertical"
+                   HsvColor="{Binding HsvColor, ElementName=ColorSpectrum2}" />
+      <ColorSpectrum x:Name="ColorSpectrum2"
+                     Grid.Column="1"
+                     Grid.Row="0"
+                     Color="Green"
+                     Shape="Ring"
+                     Height="256"
+                     Width="256" />
+      <ColorSlider Grid.Column="2"
                    Grid.Row="0"
-                   Color="Green"
-                   Shape="Ring"
-                   Height="256"
-                   Width="256" />
-    <ColorSpectrum Grid.Column="0"
-                   Grid.Row="1"
-                   CornerRadius="10"
-                   Color="Blue"
-                   Height="256"
-                   Width="256" />
+                   ColorComponent="Alpha"
+                   ColorModel="Hsva"
+                   Orientation="Vertical"
+                   HsvColor="{Binding HsvColor, ElementName=ColorSpectrum2}" />
+      <ColorPreviewer Grid.Column="0"
+                      Grid.ColumnSpan="3"
+                      Grid.Row="1"
+                      ShowAccentColors="True"
+                      HsvColor="{Binding HsvColor, ElementName=ColorSpectrum2}" />
+    </Grid>
   </Grid>
 </UserControl>

src/Avalonia.Base/Controls/ResourceNodeExtensions.cs

@@ -40,19 +40,16 @@ namespace Avalonia.Controls
             control = control ?? throw new ArgumentNullException(nameof(control));
             key = key ?? throw new ArgumentNullException(nameof(key));
 
-            IResourceHost? current = control;
+            IResourceNode? current = control;
 
             while (current != null)
             {
-                if (current is IResourceHost host)
+                if (current.TryGetResource(key, out value))
                 {
-                    if (host.TryGetResource(key, out value))
-                    {
-                        return true;
-                    }
+                    return true;
                 }
 
-                current = (current as IStyledElement)?.StylingParent as IResourceHost;
+                current = (current as IStyledElement)?.StylingParent as IResourceNode;
             }
 
             value = null;

src/Avalonia.Base/Media/GlyphRun.cs

@@ -28,6 +28,8 @@ namespace Avalonia.Media
         private IReadOnlyList<Vector>? _glyphOffsets;
         private IReadOnlyList<int>? _glyphClusters;
 
+        private int _offsetToFirstCharacter;
+
         /// <summary>
         ///     Initializes a new instance of the <see cref="GlyphRun"/> class by specifying properties of the class.
         /// </summary>
@@ -49,7 +51,7 @@ namespace Avalonia.Media
             IReadOnlyList<int>? glyphClusters = null,
             int biDiLevel = 0)
         {
-            _glyphTypeface = glyphTypeface;  
+            _glyphTypeface = glyphTypeface;
 
             FontRenderingEmSize = fontRenderingEmSize;
 
@@ -203,8 +205,8 @@ namespace Avalonia.Media
         /// </returns>
         public double GetDistanceFromCharacterHit(CharacterHit characterHit)
         {
-            var characterIndex = characterHit.FirstCharacterIndex + characterHit.TrailingLength;
-           
+            var characterIndex = characterHit.FirstCharacterIndex + characterHit.TrailingLength - _offsetToFirstCharacter;
+
             var distance = 0.0;
 
             if (IsLeftToRight)
@@ -223,7 +225,7 @@ namespace Avalonia.Media
                 }
 
                 var glyphIndex = FindGlyphIndex(characterIndex);
-                
+
                 if (GlyphClusters != null)
                 {
                     var currentCluster = GlyphClusters[glyphIndex];
@@ -249,7 +251,7 @@ namespace Avalonia.Media
             {
                 //RightToLeft
                 var glyphIndex = FindGlyphIndex(characterIndex);
-                
+
                 if (GlyphClusters != null)
                 {
                     if (characterIndex > GlyphClusters[0])
@@ -284,13 +286,13 @@ namespace Avalonia.Media
         public CharacterHit GetCharacterHitFromDistance(double distance, out bool isInside)
         {
             var characterIndex = 0;
-            
+
             // Before
             if (distance <= 0)
             {
                 isInside = false;
 
-                if(GlyphClusters != null)
+                if (GlyphClusters != null)
                 {
                     characterIndex = GlyphClusters[characterIndex];
                 }
@@ -307,11 +309,11 @@ namespace Avalonia.Media
 
                 characterIndex = GlyphIndices.Count - 1;
 
-                if(GlyphClusters != null)
+                if (GlyphClusters != null)
                 {
                     characterIndex = GlyphClusters[characterIndex];
                 }
-                
+
                 var lastCharacterHit = FindNearestCharacterHit(characterIndex, out _);
 
                 return IsLeftToRight ? lastCharacterHit : new CharacterHit(lastCharacterHit.FirstCharacterIndex);
@@ -327,7 +329,7 @@ namespace Avalonia.Media
                     var advance = GetGlyphAdvance(index, out var cluster);
 
                     characterIndex = cluster;
-                    
+
                     if (distance > currentX && distance <= currentX + advance)
                     {
                         break;
@@ -345,7 +347,7 @@ namespace Avalonia.Media
                     var advance = GetGlyphAdvance(index, out var cluster);
 
                     characterIndex = cluster;
-                    
+
                     if (currentX - advance < distance)
                     {
                         break;
@@ -552,20 +554,20 @@ namespace Avalonia.Media
                 }
 
                 nextCluster = GlyphClusters[currentIndex];
-            }
+            }           
 
             int trailingLength;
 
             if (nextCluster == cluster)
             {
-                trailingLength = Characters.Start + Characters.Length - cluster;
+                trailingLength = Characters.Start + Characters.Length - _offsetToFirstCharacter - cluster;
             }
             else
             {
                 trailingLength = nextCluster - cluster;
             }
 
-            return new CharacterHit(cluster, trailingLength);
+            return new CharacterHit(_offsetToFirstCharacter + cluster, trailingLength);
         }
 
         /// <summary>
@@ -577,7 +579,7 @@ namespace Avalonia.Media
         private double GetGlyphAdvance(int index, out int cluster)
         {
             cluster = GlyphClusters != null ? GlyphClusters[index] : index;
-            
+
             if (GlyphAdvances != null)
             {
                 return GlyphAdvances[index];
@@ -599,11 +601,18 @@ namespace Avalonia.Media
 
         private GlyphRunMetrics CreateGlyphRunMetrics()
         {
+            if (GlyphClusters != null && GlyphClusters.Count > 0)
+            {
+                var firstCluster = GlyphClusters[0];
+
+                _offsetToFirstCharacter = Math.Max(0, Characters.Start - firstCluster);
+            }
+
             var height = (GlyphTypeface.Descent - GlyphTypeface.Ascent + GlyphTypeface.LineGap) * Scale;
             var widthIncludingTrailingWhitespace = 0d;
 
             var trailingWhitespaceLength = GetTrailingWhitespaceLength(out var newLineLength, out var glyphCount);
-            
+
             for (var index = 0; index < GlyphIndices.Count; index++)
             {
                 var advance = GetGlyphAdvance(index, out _);
@@ -615,7 +624,7 @@ namespace Avalonia.Media
 
             if (IsLeftToRight)
             {
-                for (var index = GlyphIndices.Count - glyphCount; index <GlyphIndices.Count; index++)
+                for (var index = GlyphIndices.Count - glyphCount; index < GlyphIndices.Count; index++)
                 {
                     width -= GetGlyphAdvance(index, out _);
                 }
@@ -670,34 +679,40 @@ namespace Avalonia.Media
             {
                 for (var i = GlyphClusters.Count - 1; i >= 0; i--)
                 {
-                    var cluster = GlyphClusters[i];
+                    var currentCluster = GlyphClusters[i];
+                    var characterIndex = Math.Max(0, currentCluster - _characters.BufferOffset);
+                    var codepoint = Codepoint.ReadAt(_characters, characterIndex, out _);
 
-                    var codepointIndex = IsLeftToRight ? cluster - _characters.Start : _characters.End - cluster;
-
-                    if (codepointIndex < 0)
+                    if (!codepoint.IsWhiteSpace)
                     {
-                        trailingWhitespaceLength = _characters.Length;
-                        
-                        glyphCount = GlyphClusters.Count;
-                        
                         break;
                     }
-                    
-                    var codepoint = Codepoint.ReadAt(_characters, codepointIndex, out _);
 
-                    if (!codepoint.IsWhiteSpace)
+                    var clusterLength = 1;
+
+                    while(i - 1 >= 0)
                     {
+                        var nextCluster = GlyphClusters[i - 1];
+
+                        if(currentCluster == nextCluster)
+                        {
+                            clusterLength++;
+                            i--;
+
+                            continue;
+                        }
+
                         break;
                     }
 
                     if (codepoint.IsBreakChar)
                     {
-                        newLineLength++;
+                        newLineLength += clusterLength;
                     }
 
-                    trailingWhitespaceLength++;
-                    
-                    glyphCount++;
+                    trailingWhitespaceLength += clusterLength;
+                   
+                    glyphCount++;                   
                 }
             }
 

src/Avalonia.Base/Media/TextFormatting/TextFormatter.cs

@@ -1,6 +1,4 @@
-using Avalonia.Media.TextFormatting.Unicode;
-
-namespace Avalonia.Media.TextFormatting
+namespace Avalonia.Media.TextFormatting
 {
     /// <summary>
     /// Represents a base class for text formatting.

src/Avalonia.Base/Media/TextFormatting/TextFormatterImpl.cs

@@ -8,6 +8,8 @@ namespace Avalonia.Media.TextFormatting
 {
     internal class TextFormatterImpl : TextFormatter
     {
+        private static readonly char[] s_empty = { ' ' };
+
         /// <inheritdoc cref="TextFormatter.FormatLine"/>
         public override TextLine FormatLine(ITextSource textSource, int firstTextSourceIndex, double paragraphWidth,
             TextParagraphProperties paragraphProperties, TextLineBreak? previousLineBreak = null)
@@ -77,14 +79,14 @@ namespace Avalonia.Media.TextFormatting
             {
                 var currentRun = textRuns[i];
 
-                if (currentLength + currentRun.Text.Length < length)
+                if (currentLength + currentRun.TextSourceLength < length)
                 {
                     currentLength += currentRun.TextSourceLength;
 
                     continue;
                 }
 
-                var firstCount = currentRun.Text.Length >= 1 ? i + 1 : i;
+                var firstCount = currentRun.TextSourceLength >= 1 ? i + 1 : i;
 
                 var first = new List<DrawableTextRun>(firstCount);
 
@@ -98,13 +100,13 @@ namespace Avalonia.Media.TextFormatting
 
                 var secondCount = textRuns.Count - firstCount;
 
-                if (currentLength + currentRun.Text.Length == length)
+                if (currentLength + currentRun.TextSourceLength == length)
                 {
                     var second = secondCount > 0 ? new List<DrawableTextRun>(secondCount) : null;
 
                     if (second != null)
                     {
-                        var offset = currentRun.Text.Length >= 1 ? 1 : 0;
+                        var offset = currentRun.TextSourceLength >= 1 ? 1 : 0;
 
                         for (var j = 0; j < secondCount; j++)
                         {
@@ -122,16 +124,14 @@ namespace Avalonia.Media.TextFormatting
 
                     var second = new List<DrawableTextRun>(secondCount);
 
-                    if (currentRun is not ShapedTextCharacters shapedTextCharacters)
+                    if (currentRun is ShapedTextCharacters shapedTextCharacters)
                     {
-                        throw new NotSupportedException("Only shaped runs can be split in between.");
-                    }
-
-                    var split = shapedTextCharacters.Split(length - currentLength);
+                        var split = shapedTextCharacters.Split(length - currentLength);
 
-                    first.Add(split.First);
+                        first.Add(split.First);
 
-                    second.Add(split.Second!);
+                        second.Add(split.Second!);
+                    }                
 
                     for (var j = 1; j < secondCount; j++)
                     {
@@ -267,7 +267,6 @@ namespace Avalonia.Media.TextFormatting
             IReadOnlyList<ShapeableTextCharacters> textRuns, ReadOnlySlice<char> text, TextShaperOptions options)
         {
             var shapedRuns = new List<ShapedTextCharacters>(textRuns.Count);
-            var firstRun = textRuns[0];
 
             var shapedBuffer = TextShaper.Current.ShapeText(text, options);
 
@@ -471,11 +470,10 @@ namespace Avalonia.Media.TextFormatting
             return false;
         }
 
-        private static bool TryMeasureLength(IReadOnlyList<DrawableTextRun> textRuns, int firstTextSourceIndex, double paragraphWidth, out int measuredLength)
+        private static bool TryMeasureLength(IReadOnlyList<DrawableTextRun> textRuns, double paragraphWidth, out int measuredLength)
         {
             measuredLength = 0;
             var currentWidth = 0.0;
-            var lastCluster = firstTextSourceIndex;
 
             foreach (var currentRun in textRuns)
             {
@@ -483,12 +481,17 @@ namespace Avalonia.Media.TextFormatting
                 {
                     case ShapedTextCharacters shapedTextCharacters:
                         {
+                            var firstCluster = shapedTextCharacters.ShapedBuffer.GlyphClusters[0];
+                            var lastCluster = firstCluster;
+
                             for (var i = 0; i < shapedTextCharacters.ShapedBuffer.Length; i++)
                             {
                                 var glyphInfo = shapedTextCharacters.ShapedBuffer[i];
 
                                 if (currentWidth + glyphInfo.GlyphAdvance > paragraphWidth)
                                 {
+                                    measuredLength += Math.Max(0, lastCluster - firstCluster);
+
                                     goto found;
                                 }
 
@@ -496,6 +499,8 @@ namespace Avalonia.Media.TextFormatting
                                 currentWidth += glyphInfo.GlyphAdvance;
                             }
 
+                            measuredLength += currentRun.TextSourceLength;
+
                             break;
                         }
 
@@ -506,7 +511,7 @@ namespace Avalonia.Media.TextFormatting
                                 goto found;
                             }
 
-                            lastCluster += currentRun.TextSourceLength;
+                            measuredLength += currentRun.TextSourceLength;
                             currentWidth += currentRun.Size.Width;
 
                             break;
@@ -516,11 +521,30 @@ namespace Avalonia.Media.TextFormatting
 
             found:
 
-            measuredLength = Math.Max(0, lastCluster - firstTextSourceIndex + 1);
-
             return measuredLength != 0;
         }
 
+        /// <summary>
+        /// Creates an empty text line.
+        /// </summary>
+        /// <returns>The empty text line.</returns>
+        public static TextLineImpl CreateEmptyTextLine(int firstTextSourceIndex, double paragraphWidth, TextParagraphProperties paragraphProperties)
+        {
+            var flowDirection = paragraphProperties.FlowDirection;
+            var properties = paragraphProperties.DefaultTextRunProperties;
+            var glyphTypeface = properties.Typeface.GlyphTypeface;
+            var text = new ReadOnlySlice<char>(s_empty, firstTextSourceIndex, 1);
+            var glyph = glyphTypeface.GetGlyph(s_empty[0]);
+            var glyphInfos = new[] { new GlyphInfo(glyph, firstTextSourceIndex) };
+
+            var shapedBuffer = new ShapedBuffer(text, glyphInfos, glyphTypeface, properties.FontRenderingEmSize,
+                (sbyte)flowDirection);
+
+            var textRuns = new List<DrawableTextRun> { new ShapedTextCharacters(shapedBuffer, properties) };
+
+            return new TextLineImpl(textRuns, firstTextSourceIndex, 0, paragraphWidth, paragraphProperties, flowDirection).FinalizeLine();
+        }
+
         /// <summary>
         /// Performs text wrapping returns a list of text lines.
         /// </summary>
@@ -535,7 +559,12 @@ namespace Avalonia.Media.TextFormatting
             double paragraphWidth, TextParagraphProperties paragraphProperties, FlowDirection flowDirection,
             TextLineBreak? currentLineBreak)
         {
-            if (!TryMeasureLength(textRuns, firstTextSourceIndex, paragraphWidth, out var measuredLength))
+            if(textRuns.Count == 0)
+            {
+                return CreateEmptyTextLine(firstTextSourceIndex,paragraphWidth, paragraphProperties);
+            }
+
+            if (!TryMeasureLength(textRuns, paragraphWidth, out var measuredLength))
             {
                 measuredLength = 1;
             }

src/Avalonia.Base/Media/TextFormatting/TextLayout.cs

@@ -10,13 +10,12 @@ namespace Avalonia.Media.TextFormatting
     /// </summary>
     public class TextLayout
     {
-        private static readonly char[] s_empty = { ' ' };
-
-        private readonly ReadOnlySlice<char> _text;
+        private readonly ITextSource _textSource;
         private readonly TextParagraphProperties _paragraphProperties;
-        private readonly IReadOnlyList<ValueSpan<TextRunProperties>>? _textStyleOverrides;
         private readonly TextTrimming _textTrimming;
 
+        private int _textSourceLength;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="TextLayout" /> class.
         /// </summary>
@@ -50,17 +49,49 @@ namespace Avalonia.Media.TextFormatting
             int maxLines = 0,
             IReadOnlyList<ValueSpan<TextRunProperties>>? textStyleOverrides = null)
         {
-            _text = string.IsNullOrEmpty(text) ?
-                new ReadOnlySlice<char>() :
-                new ReadOnlySlice<char>(text.AsMemory());
-
             _paragraphProperties =
                 CreateTextParagraphProperties(typeface, fontSize, foreground, textAlignment, textWrapping,
                     textDecorations, flowDirection, lineHeight);
 
+            _textSource = new FormattedTextSource(text.AsMemory(), _paragraphProperties.DefaultTextRunProperties, textStyleOverrides);
+
             _textTrimming = textTrimming ?? TextTrimming.None;
 
-            _textStyleOverrides = textStyleOverrides;
+            LineHeight = lineHeight;
+
+            MaxWidth = maxWidth;
+
+            MaxHeight = maxHeight;
+
+            MaxLines = maxLines;      
+
+            TextLines = CreateTextLines();
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TextLayout" /> class.
+        /// </summary>
+        /// <param name="textSource">The text source.</param>
+        /// <param name="paragraphProperties">The default text paragraph properties.</param>
+        /// <param name="textTrimming">The text trimming.</param>
+        /// <param name="maxWidth">The maximum width.</param>
+        /// <param name="maxHeight">The maximum height.</param>
+        /// <param name="lineHeight">The height of each line of text.</param>
+        /// <param name="maxLines">The maximum number of text lines.</param>
+        public TextLayout(
+            ITextSource textSource,
+            TextParagraphProperties paragraphProperties, 
+            TextTrimming? textTrimming = null,
+            double maxWidth = double.PositiveInfinity,
+            double maxHeight = double.PositiveInfinity,
+            double lineHeight = double.NaN,
+            int maxLines = 0)
+        {
+            _textSource = textSource;
+
+            _paragraphProperties = paragraphProperties;
+
+            _textTrimming = textTrimming ?? TextTrimming.None;
 
             LineHeight = lineHeight;
 
@@ -147,7 +178,7 @@ namespace Avalonia.Media.TextFormatting
                 return new Rect();
             }
 
-            if (textPosition < 0 || textPosition >= _text.Length)
+            if (textPosition < 0 || textPosition >= _textSourceLength)
             {
                 var lastLine = TextLines[TextLines.Count - 1];
 
@@ -273,7 +304,7 @@ namespace Avalonia.Media.TextFormatting
                 return 0;
             }
 
-            if (charIndex > _text.Length)
+            if (charIndex > _textSourceLength)
             {
                 return TextLines.Count - 1;
             }
@@ -375,32 +406,11 @@ namespace Avalonia.Media.TextFormatting
             height += textLine.Height;
         }
 
-        /// <summary>
-        /// Creates an empty text line.
-        /// </summary>
-        /// <returns>The empty text line.</returns>
-        private TextLine CreateEmptyTextLine(int firstTextSourceIndex)
-        {
-            var flowDirection = _paragraphProperties.FlowDirection;
-            var properties = _paragraphProperties.DefaultTextRunProperties;
-            var glyphTypeface = properties.Typeface.GlyphTypeface;
-            var text = new ReadOnlySlice<char>(s_empty, firstTextSourceIndex, 1);
-            var glyph = glyphTypeface.GetGlyph(s_empty[0]);
-            var glyphInfos = new[] { new GlyphInfo(glyph, firstTextSourceIndex) };
-
-            var shapedBuffer = new ShapedBuffer(text, glyphInfos, glyphTypeface, properties.FontRenderingEmSize,
-                (sbyte)flowDirection);
-
-            var textRuns = new List<DrawableTextRun> { new ShapedTextCharacters(shapedBuffer, properties) };
-
-            return new TextLineImpl(textRuns, firstTextSourceIndex, 1, MaxWidth, _paragraphProperties, flowDirection).FinalizeLine();
-        }
-
         private IReadOnlyList<TextLine> CreateTextLines()
         {
-            if (_text.IsEmpty || MathUtilities.IsZero(MaxWidth) || MathUtilities.IsZero(MaxHeight))
+            if (MathUtilities.IsZero(MaxWidth) || MathUtilities.IsZero(MaxHeight))
             {
-                var textLine = CreateEmptyTextLine(0);
+                var textLine = TextFormatterImpl.CreateEmptyTextLine(0, double.PositiveInfinity, _paragraphProperties);
 
                 Bounds = new Rect(0,0,0, textLine.Height);
 
@@ -411,26 +421,30 @@ namespace Avalonia.Media.TextFormatting
 
             double left = double.PositiveInfinity, width = 0.0, height = 0.0;
 
-            var currentPosition = 0;
-
-            var textSource = new FormattedTextSource(_text,
-                _paragraphProperties.DefaultTextRunProperties, _textStyleOverrides);
+            _textSourceLength = 0;
 
             TextLine? previousLine = null;
 
-            while (currentPosition < _text.Length)
+            while (true)
             {
-                var textLine = TextFormatter.Current.FormatLine(textSource, currentPosition, MaxWidth,
+                var textLine = TextFormatter.Current.FormatLine(_textSource, _textSourceLength, MaxWidth,
                     _paragraphProperties, previousLine?.TextLineBreak);
 
-#if DEBUG
-                if (textLine.Length == 0)
+                if(textLine == null || textLine.Length == 0)
                 {
-                    throw new InvalidOperationException($"{nameof(textLine)} should not be empty.");
+                    if(previousLine != null && previousLine.NewLineLength  > 0)
+                    {
+                        var emptyTextLine = TextFormatterImpl.CreateEmptyTextLine(_textSourceLength, MaxWidth, _paragraphProperties);
+
+                        textLines.Add(emptyTextLine);
+
+                        UpdateBounds(emptyTextLine, ref left, ref width, ref height);
+                    }
+
+                    break;
                 }
-#endif
 
-                currentPosition += textLine.Length;
+                _textSourceLength += textLine.Length;
                 
                 //Fulfill max height constraint
                 if (textLines.Count > 0 && !double.IsPositiveInfinity(MaxHeight) && height + textLine.Height > MaxHeight)
@@ -464,17 +478,16 @@ namespace Avalonia.Media.TextFormatting
                 {
                     break;
                 }
-                
-                if (currentPosition != _text.Length || textLine.NewLineLength <= 0)
-                {
-                    continue;
-                }
+            }
 
-                var emptyTextLine = CreateEmptyTextLine(currentPosition);
+            //Make sure the TextLayout always contains at least on empty line
+            if(textLines.Count == 0)
+            {
+                var textLine = TextFormatterImpl.CreateEmptyTextLine(0, MaxWidth, _paragraphProperties);
 
-                textLines.Add(emptyTextLine);
+                textLines.Add(textLine);
 
-                UpdateBounds(emptyTextLine,ref left, ref width, ref height);
+                UpdateBounds(textLine, ref left, ref width, ref height);
             }
 
             Bounds = new Rect(left, 0, width, height);

src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs

@@ -183,6 +183,7 @@ namespace Avalonia.Media.TextFormatting
                     case ShapedTextCharacters shapedRun:
                         {
                             characterHit = shapedRun.GlyphRun.GetCharacterHitFromDistance(distance, out _);
+
                             break;
                         }
                     default:
@@ -251,7 +252,7 @@ namespace Avalonia.Media.TextFormatting
                             //Look at the left and right edge of the current run
                             if (currentRun.IsLeftToRight)
                             {
-                                if (lastRun == null || lastRun.IsLeftToRight)
+                                if (_flowDirection == FlowDirection.LeftToRight && (lastRun == null || lastRun.IsLeftToRight))
                                 {
                                     if (characterIndex <= textRun.Text.Start)
                                     {
@@ -403,7 +404,7 @@ namespace Avalonia.Media.TextFormatting
             var result = new List<TextBounds>(TextRuns.Count);
             var lastDirection = _flowDirection;
             var currentDirection = lastDirection;
-            var currentPosition = 0;
+            var currentPosition = FirstTextSourceIndex;
             var currentRect = Rect.Empty;
             var startX = Start;
 
@@ -426,31 +427,42 @@ namespace Avalonia.Media.TextFormatting
 
                 if (nextRun != null)
                 {
-                    if (nextRun.Text.Start < currentRun.Text.Start && firstTextSourceCharacterIndex + textLength < currentRun.Text.End)
+                    switch (nextRun)
                     {
-                        goto skip;
-                    }
+                        case ShapedTextCharacters when currentRun is ShapedTextCharacters:
+                            {
+                                if (nextRun.Text.Start < currentRun.Text.Start && firstTextSourceCharacterIndex + textLength < currentRun.Text.End)
+                                {
+                                    goto skip;
+                                }
 
-                    if (currentRun.Text.Start >= firstTextSourceCharacterIndex + textLength)
-                    {
-                        goto skip;
-                    }
+                                if (currentRun.Text.Start >= firstTextSourceCharacterIndex + textLength)
+                                {
+                                    goto skip;
+                                }
 
-                    if (currentRun.Text.Start > nextRun.Text.Start && currentRun.Text.Start < firstTextSourceCharacterIndex)
-                    {
-                        goto skip;
-                    }
+                                if (currentRun.Text.Start > nextRun.Text.Start && currentRun.Text.Start < firstTextSourceCharacterIndex)
+                                {
+                                    goto skip;
+                                }
 
-                    if (currentRun.Text.End < firstTextSourceCharacterIndex)
-                    {
-                        goto skip;
-                    }
+                                if (currentRun.Text.End < firstTextSourceCharacterIndex)
+                                {
+                                    goto skip;
+                                }
 
-                    goto noop;
+                                goto noop;
+                            }
+                        default:
+                            {
+                                goto noop;
+                            }
+                    }
 
                 skip:
                     {
                         startX += currentRun.Size.Width;
+                        currentPosition += currentRun.TextSourceLength;
                     }
 
                     continue;
@@ -460,7 +472,6 @@ namespace Avalonia.Media.TextFormatting
                     }
                 }
 
-
                 var endX = startX;
                 var endOffset = 0d;
 
@@ -520,11 +531,18 @@ namespace Avalonia.Media.TextFormatting
                         }
                     default:
                         {
-                            if (firstTextSourceCharacterIndex + textLength >= currentRun.Text.Start + currentRun.Text.Length)
+                            if (currentPosition + currentRun.TextSourceLength <= firstTextSourceCharacterIndex + textLength)
                             {
                                 endX += currentRun.Size.Width;
                             }
 
+                            if (currentPosition < firstTextSourceCharacterIndex)
+                            {
+                                startX += currentRun.Size.Width;
+                            }
+
+                            currentPosition += currentRun.TextSourceLength;
+
                             break;
                         }
                 }
@@ -536,36 +554,31 @@ namespace Avalonia.Media.TextFormatting
 
                 var width = endX - startX;
 
-                if (lastDirection == currentDirection && result.Count > 0 && MathUtilities.AreClose(currentRect.Right, startX))
+                if (!MathUtilities.IsZero(width))
                 {
-                    var textBounds = new TextBounds(currentRect.WithWidth(currentRect.Width + width), currentDirection);
+                    if (lastDirection == currentDirection && result.Count > 0 && MathUtilities.AreClose(currentRect.Right, startX))
+                    {
+                        currentRect = currentRect.WithWidth(currentRect.Width + width);
 
-                    result[result.Count - 1] = textBounds;
-                }
-                else
-                {
-                    currentRect = new Rect(startX, 0, width, Height);
+                        var textBounds = new TextBounds(currentRect, currentDirection);
 
-                    result.Add(new TextBounds(currentRect, currentDirection));
+                        result[result.Count - 1] = textBounds;
+                    }
+                    else
+                    {
+
+                        currentRect = new Rect(startX, 0, width, Height);
+
+                        result.Add(new TextBounds(currentRect, currentDirection));
+
+                    }
                 }
 
                 if (currentDirection == FlowDirection.LeftToRight)
                 {
-                    if (nextRun != null)
-                    {
-                        if (nextRun.Text.Start > currentRun.Text.Start && nextRun.Text.Start >= firstTextSourceCharacterIndex + textLength)
-                        {
-                            break;
-                        }
-
-                        currentPosition = nextRun.Text.End;
-                    }
-                    else
+                    if (currentPosition > firstTextSourceCharacterIndex + textLength)
                     {
-                        if (currentPosition >= firstTextSourceCharacterIndex + textLength)
-                        {
-                            break;
-                        }
+                        break;
                     }
                 }
                 else
@@ -575,10 +588,7 @@ namespace Avalonia.Media.TextFormatting
                         break;
                     }
 
-                    if (currentPosition != currentRun.Text.Start)
-                    {
-                        endX += currentRun.Size.Width - endOffset;
-                    }
+                    endX += currentRun.Size.Width - endOffset;
                 }
 
                 lastDirection = currentDirection;
@@ -590,10 +600,10 @@ namespace Avalonia.Media.TextFormatting
 
         public TextLineImpl FinalizeLine()
         {
-            BidiReorder();
-
             _textLineMetrics = CreateLineMetrics();
 
+            BidiReorder();
+
             return this;
         }
 
@@ -1018,31 +1028,21 @@ namespace Avalonia.Media.TextFormatting
 
         private TextLineMetrics CreateLineMetrics()
         {
-            var start = 0d;
-            var height = 0d;
+            var glyphTypeface = _paragraphProperties.DefaultTextRunProperties.Typeface.GlyphTypeface;
+            var fontRenderingEmSize = _paragraphProperties.DefaultTextRunProperties.FontRenderingEmSize;
+            var scale = fontRenderingEmSize / glyphTypeface.DesignEmHeight;
+
             var width = 0d;
             var widthIncludingWhitespace = 0d;
             var trailingWhitespaceLength = 0;
             var newLineLength = 0;
-            var ascent = 0d;
-            var descent = 0d;
-            var lineGap = 0d;
-            var fontRenderingEmSize = 0d;
+            var ascent = glyphTypeface.Ascent * scale;
+            var descent = glyphTypeface.Descent * scale;
+            var lineGap = glyphTypeface.LineGap * scale;
 
-            var lineHeight = _paragraphProperties.LineHeight;
+            var height = descent - ascent + lineGap;
 
-            if (_textRuns.Count == 0)
-            {
-                var glyphTypeface = _paragraphProperties.DefaultTextRunProperties.Typeface.GlyphTypeface;
-                fontRenderingEmSize = _paragraphProperties.DefaultTextRunProperties.FontRenderingEmSize;
-                var scale = fontRenderingEmSize / glyphTypeface.DesignEmHeight;
-                ascent = glyphTypeface.Ascent * scale;
-                height = double.IsNaN(lineHeight) || MathUtilities.IsZero(lineHeight) ?
-                descent - ascent + lineGap :
-                lineHeight;
-
-                return new TextLineMetrics(false, height, 0, start, -ascent, 0, 0, 0);
-            }
+            var lineHeight = _paragraphProperties.LineHeight;
 
             for (var index = 0; index < _textRuns.Count; index++)
             {
@@ -1078,41 +1078,11 @@ namespace Avalonia.Media.TextFormatting
                                 }
                             }
 
-                            switch (_paragraphProperties.FlowDirection)
+                            if (index == _textRuns.Count - 1)
                             {
-                                case FlowDirection.LeftToRight:
-                                    {
-                                        if (index == _textRuns.Count - 1)
-                                        {
-                                            width = widthIncludingWhitespace + textRun.GlyphRun.Metrics.Width;
-                                            trailingWhitespaceLength = textRun.GlyphRun.Metrics.TrailingWhitespaceLength;
-                                            newLineLength = textRun.GlyphRun.Metrics.NewlineLength;
-                                        }
-
-                                        break;
-                                    }
-
-                                case FlowDirection.RightToLeft:
-                                    {
-                                        if (index == _textRuns.Count - 1)
-                                        {
-                                            var firstRun = _textRuns[0];
-
-                                            if (firstRun is ShapedTextCharacters shapedTextCharacters)
-                                            {
-                                                var offset = shapedTextCharacters.GlyphRun.Metrics.WidthIncludingTrailingWhitespace -
-                                                             shapedTextCharacters.GlyphRun.Metrics.Width;
-
-                                                width = widthIncludingWhitespace +
-                                                    textRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace - offset;
-
-                                                trailingWhitespaceLength = shapedTextCharacters.GlyphRun.Metrics.TrailingWhitespaceLength;
-                                                newLineLength = shapedTextCharacters.GlyphRun.Metrics.NewlineLength;
-                                            }
-                                        }
-
-                                        break;
-                                    }
+                                width = widthIncludingWhitespace + textRun.GlyphRun.Metrics.Width;
+                                trailingWhitespaceLength = textRun.GlyphRun.Metrics.TrailingWhitespaceLength;
+                                newLineLength = textRun.GlyphRun.Metrics.NewlineLength;
                             }
 
                             widthIncludingWhitespace += textRun.GlyphRun.Metrics.WidthIncludingTrailingWhitespace;
@@ -1166,12 +1136,15 @@ namespace Avalonia.Media.TextFormatting
                 }
             }
 
-            start = GetParagraphOffsetX(width, widthIncludingWhitespace, _paragraphWidth,
+            var start = GetParagraphOffsetX(width, widthIncludingWhitespace, _paragraphWidth,
                 _paragraphProperties.TextAlignment, _paragraphProperties.FlowDirection);
 
             if (!double.IsNaN(lineHeight) && !MathUtilities.IsZero(lineHeight))
             {
-                height = lineHeight;
+                if (lineHeight > height)
+                {
+                    height = lineHeight;
+                }
             }
 
             return new TextLineMetrics(widthIncludingWhitespace > _paragraphWidth, height, newLineLength, start,

src/Avalonia.Base/Media/TextFormatting/Unicode/BiDiAlgorithm.cs

@@ -238,6 +238,11 @@ namespace Avalonia.Media.TextFormatting.Unicode
             _levelRuns.Clear();
             _resolvedLevelsBuffer.Clear();
 
+            if (types.IsEmpty)
+            {
+                return;
+            }
+
             // Setup original types and working types
             _originalClasses = types;
             _workingClasses = _workingClassesBuffer.Add(types);

src/Avalonia.Base/Styling/IStyle.cs

@@ -8,7 +8,7 @@ namespace Avalonia.Styling
     /// <summary>
     /// Defines the interface for styles.
     /// </summary>
-    public interface IStyle
+    public interface IStyle : IResourceNode
     {
         /// <summary>
         /// Gets a collection of child styles.

src/Avalonia.Base/Styling/Styles.cs

@@ -160,7 +160,7 @@ namespace Avalonia.Styling
 
             for (var i = Count - 1; i >= 0; --i)
             {
-                if (this[i] is IResourceProvider p && p.TryGetResource(key, out value))
+                if (this[i].TryGetResource(key, out value))
                 {
                     return true;
                 }

src/Avalonia.Base/Utilities/WeakHashList.cs

@@ -118,7 +118,7 @@ internal class WeakHashList<T> where T : class
     {
         if (_arr != null)
         {
-            for (var c = 0; c < _arr.Length; c++)
+            for (var c = 0; c < _arrCount; c++)
             {
                 if (_arr[c]?.TryGetTarget(out var target) == true && target == item)
                 {

src/Avalonia.Controls.ColorPicker/ColorComponent.cs

@@ -0,0 +1,28 @@
+namespace Avalonia.Controls
+{
+    /// <summary>
+    /// Defines a specific component within a color model.
+    /// </summary>
+    public enum ColorComponent
+    {
+        /// <summary>
+        /// Represents the alpha component.
+        /// </summary>
+        Alpha = 0,
+
+        /// <summary>
+        /// Represents the first color component which is Red when RGB or Hue when HSV.
+        /// </summary>
+        Component1 = 1,
+
+        /// <summary>
+        /// Represents the second color component which is Green when RGB or Saturation when HSV.
+        /// </summary>
+        Component2 = 2,
+
+        /// <summary>
+        /// Represents the third color component which is Blue when RGB or Value when HSV.
+        /// </summary>
+        Component3 = 3
+    }
+}

src/Avalonia.Controls.ColorPicker/ColorModel.cs

@@ -0,0 +1,18 @@
+namespace Avalonia.Controls
+{
+    /// <summary>
+    /// Defines the model used to represent colors.
+    /// </summary>
+    public enum ColorModel
+    {
+        /// <summary>
+        /// Color is represented by hue, saturation, value and alpha components.
+        /// </summary>
+        Hsva,
+
+        /// <summary>
+        /// Color is represented by red, green, blue and alpha components.
+        /// </summary>
+        Rgba
+    }
+}

src/Avalonia.Controls.ColorPicker/ColorPreviewer/ColorPreviewer.Properties.cs

@@ -0,0 +1,50 @@
+using Avalonia.Data;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Primitives
+{
+    /// <inheritdoc/>
+    public partial class ColorPreviewer
+    {
+        /// <summary>
+        /// Defines the <see cref="HsvColor"/> property.
+        /// </summary>
+        public static readonly StyledProperty<HsvColor> HsvColorProperty =
+            AvaloniaProperty.Register<ColorPreviewer, HsvColor>(
+                nameof(HsvColor),
+                Colors.Transparent.ToHsv(),
+                defaultBindingMode: BindingMode.TwoWay);
+
+        /// <summary>
+        /// Defines the <see cref="ShowAccentColors"/> property.
+        /// </summary>
+        public static readonly StyledProperty<bool> ShowAccentColorsProperty =
+            AvaloniaProperty.Register<ColorPreviewer, bool>(
+                nameof(ShowAccentColors),
+                true);
+
+        /// <summary>
+        /// Gets or sets the currently previewed color in the HSV color model.
+        /// </summary>
+        /// <remarks>
+        /// Only an HSV color is supported in this control to ensure there is never any
+        /// loss of precision or color information. Accent colors, like the color spectrum,
+        /// only operate with the HSV color model.
+        /// </remarks>
+        public HsvColor HsvColor
+        {
+            get => GetValue(HsvColorProperty);
+            set => SetValue(HsvColorProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether accent colors are shown along
+        /// with the preview color.
+        /// </summary>
+        public bool ShowAccentColors
+        {
+            get => GetValue(ShowAccentColorsProperty);
+            set => SetValue(ShowAccentColorsProperty, value);
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/ColorPreviewer/ColorPreviewer.cs

@@ -0,0 +1,130 @@
+using System;
+using System.Globalization;
+using Avalonia.Controls.Metadata;
+using Avalonia.Controls.Primitives.Converters;
+using Avalonia.Input;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Primitives
+{
+    /// <summary>
+    /// Presents a preview color with optional accent colors.
+    /// </summary>
+    [TemplatePart(Name = nameof(AccentDec1Border), Type = typeof(Border))]
+    [TemplatePart(Name = nameof(AccentDec2Border), Type = typeof(Border))]
+    [TemplatePart(Name = nameof(AccentInc1Border), Type = typeof(Border))]
+    [TemplatePart(Name = nameof(AccentInc2Border), Type = typeof(Border))]
+    public partial class ColorPreviewer : TemplatedControl
+    {
+        /// <summary>
+        /// Event for when the selected color changes within the previewer.
+        /// This occurs when an accent color is pressed.
+        /// </summary>
+        public event EventHandler<ColorChangedEventArgs>? ColorChanged;
+
+        private bool eventsConnected = false;
+
+        private Border? AccentDec1Border;
+        private Border? AccentDec2Border;
+        private Border? AccentInc1Border;
+        private Border? AccentInc2Border;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ColorPreviewer"/> class.
+        /// </summary>
+        public ColorPreviewer() : base()
+        {
+        }
+
+        /// <summary>
+        /// Connects or disconnects all control event handlers.
+        /// </summary>
+        /// <param name="connected">True to connect event handlers, otherwise false.</param>
+        private void ConnectEvents(bool connected)
+        {
+            if (connected == true && eventsConnected == false)
+            {
+                // Add all events
+                if (AccentDec1Border != null) { AccentDec1Border.PointerPressed += AccentBorder_PointerPressed; }
+                if (AccentDec2Border != null) { AccentDec2Border.PointerPressed += AccentBorder_PointerPressed; }
+                if (AccentInc1Border != null) { AccentInc1Border.PointerPressed += AccentBorder_PointerPressed; }
+                if (AccentInc2Border != null) { AccentInc2Border.PointerPressed += AccentBorder_PointerPressed; }
+
+                eventsConnected = true;
+            }
+            else if (connected == false && eventsConnected == true)
+            {
+                // Remove all events
+                if (AccentDec1Border != null) { AccentDec1Border.PointerPressed -= AccentBorder_PointerPressed; }
+                if (AccentDec2Border != null) { AccentDec2Border.PointerPressed -= AccentBorder_PointerPressed; }
+                if (AccentInc1Border != null) { AccentInc1Border.PointerPressed -= AccentBorder_PointerPressed; }
+                if (AccentInc2Border != null) { AccentInc2Border.PointerPressed -= AccentBorder_PointerPressed; }
+
+                eventsConnected = false;
+            }
+        }
+
+        /// <inheritdoc/>
+        protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
+        {
+            // Remove any existing events present if the control was previously loaded then unloaded
+            ConnectEvents(false);
+
+            AccentDec1Border = e.NameScope.Find<Border>(nameof(AccentDec1Border));
+            AccentDec2Border = e.NameScope.Find<Border>(nameof(AccentDec2Border));
+            AccentInc1Border = e.NameScope.Find<Border>(nameof(AccentInc1Border));
+            AccentInc2Border = e.NameScope.Find<Border>(nameof(AccentInc2Border));
+
+            // Must connect after controls are found
+            ConnectEvents(true);
+
+            base.OnApplyTemplate(e);
+        }
+
+        /// <inheritdoc/>
+        protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)
+        {
+            if (change.Property == HsvColorProperty)
+            {
+                OnColorChanged(new ColorChangedEventArgs(
+                    change.GetOldValue<HsvColor>().ToRgb(),
+                    change.GetNewValue<HsvColor>().ToRgb()));
+            }
+
+            base.OnPropertyChanged(change);
+        }
+
+        /// <summary>
+        /// Called before the <see cref="ColorChanged"/> event occurs.
+        /// </summary>
+        /// <param name="e">The <see cref="ColorChangedEventArgs"/> defining old/new colors.</param>
+        protected virtual void OnColorChanged(ColorChangedEventArgs e)
+        {
+            ColorChanged?.Invoke(this, e);
+        }
+
+        /// <summary>
+        /// Event handler for when an accent color border is pressed.
+        /// This will update the color to the background of the pressed panel.
+        /// </summary>
+        private void AccentBorder_PointerPressed(object? sender, PointerPressedEventArgs e)
+        {
+            Border? border = sender as Border;
+            int accentStep = 0;
+            HsvColor hsvColor = HsvColor;
+
+            // Get the value component delta
+            try
+            {
+                accentStep = int.Parse(border?.Tag?.ToString() ?? "", CultureInfo.InvariantCulture);
+            }
+            catch { }
+
+            HsvColor newHsvColor = AccentColorConverter.GetAccent(hsvColor, accentStep);
+            HsvColor oldHsvColor = HsvColor;
+
+            HsvColor = newHsvColor;
+            OnColorChanged(new ColorChangedEventArgs(oldHsvColor.ToRgb(), newHsvColor.ToRgb()));
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/ColorSlider/ColorSlider.Properties.cs

@@ -0,0 +1,146 @@
+using Avalonia.Data;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Primitives
+{
+    /// <inheritdoc/>
+    public partial class ColorSlider
+    {
+        /// <summary>
+        /// Defines the <see cref="Color"/> property.
+        /// </summary>
+        public static readonly StyledProperty<Color> ColorProperty =
+            AvaloniaProperty.Register<ColorSlider, Color>(
+                nameof(Color),
+                Colors.White,
+                defaultBindingMode: BindingMode.TwoWay);
+
+        /// <summary>
+        /// Defines the <see cref="ColorComponent"/> property.
+        /// </summary>
+        public static readonly StyledProperty<ColorComponent> ColorComponentProperty =
+            AvaloniaProperty.Register<ColorSlider, ColorComponent>(
+                nameof(ColorComponent),
+                ColorComponent.Component1);
+
+        /// <summary>
+        /// Defines the <see cref="ColorModel"/> property.
+        /// </summary>
+        public static readonly StyledProperty<ColorModel> ColorModelProperty =
+            AvaloniaProperty.Register<ColorSlider, ColorModel>(
+                nameof(ColorModel),
+                ColorModel.Rgba);
+
+        /// <summary>
+        /// Defines the <see cref="HsvColor"/> property.
+        /// </summary>
+        public static readonly StyledProperty<HsvColor> HsvColorProperty =
+            AvaloniaProperty.Register<ColorSlider, HsvColor>(
+                nameof(HsvColor),
+                Colors.White.ToHsv(),
+                defaultBindingMode: BindingMode.TwoWay);
+
+        /// <summary>
+        /// Defines the <see cref="IsAlphaMaxForced"/> property.
+        /// </summary>
+        public static readonly StyledProperty<bool> IsAlphaMaxForcedProperty =
+            AvaloniaProperty.Register<ColorSlider, bool>(
+                nameof(IsAlphaMaxForced),
+                true);
+
+        /// <summary>
+        /// Defines the <see cref="IsAutoUpdatingEnabled"/> property.
+        /// </summary>
+        public static readonly StyledProperty<bool> IsAutoUpdatingEnabledProperty =
+            AvaloniaProperty.Register<ColorSlider, bool>(
+                nameof(IsAutoUpdatingEnabled),
+                true);
+
+        /// <summary>
+        /// Defines the <see cref="IsSaturationValueMaxForced"/> property.
+        /// </summary>
+        public static readonly StyledProperty<bool> IsSaturationValueMaxForcedProperty =
+            AvaloniaProperty.Register<ColorSlider, bool>(
+                nameof(IsSaturationValueMaxForced),
+                true);
+
+        /// <summary>
+        /// Gets or sets the currently selected color in the RGB color model.
+        /// </summary>
+        /// <remarks>
+        /// Use this property instead of <see cref="HsvColor"/> when in <see cref="ColorModel.Rgba"/>
+        /// to avoid loss of precision and color drifting.
+        /// </remarks>
+        public Color Color
+        {
+            get => GetValue(ColorProperty);
+            set => SetValue(ColorProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets the color component represented by the slider.
+        /// </summary>
+        public ColorComponent ColorComponent
+        {
+            get => GetValue(ColorComponentProperty);
+            set => SetValue(ColorComponentProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets the active color model used by the slider.
+        /// </summary>
+        public ColorModel ColorModel
+        {
+            get => GetValue(ColorModelProperty);
+            set => SetValue(ColorModelProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets the currently selected color in the HSV color model.
+        /// </summary>
+        /// <remarks>
+        /// Use this property instead of <see cref="Color"/> when in <see cref="ColorModel.Hsva"/>
+        /// to avoid loss of precision and color drifting.
+        /// </remarks>
+        public HsvColor HsvColor
+        {
+            get => GetValue(HsvColorProperty);
+            set => SetValue(HsvColorProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether the alpha component is always forced to maximum for components
+        /// other than <see cref="ColorComponent"/>.
+        /// This ensures that the background is always visible and never transparent regardless of the actual color.
+        /// </summary>
+        public bool IsAlphaMaxForced
+        {
+            get => GetValue(IsAlphaMaxForcedProperty);
+            set => SetValue(IsAlphaMaxForcedProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether automatic background and foreground updates will be
+        /// calculated when the set color changes.
+        /// </summary>
+        /// <remarks>
+        /// This can be disabled for performance reasons when working with multiple sliders.
+        /// </remarks>
+        public bool IsAutoUpdatingEnabled
+        {
+            get => GetValue(IsAutoUpdatingEnabledProperty);
+            set => SetValue(IsAutoUpdatingEnabledProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether the saturation and value components are always forced to maximum values
+        /// when using the HSVA color model. Only component values other than <see cref="ColorComponent"/> will be changed.
+        /// This ensures, for example, that the Hue background is always visible and never washed out regardless of the actual color.
+        /// </summary>
+        public bool IsSaturationValueMaxForced
+        {
+            get => GetValue(IsSaturationValueMaxForcedProperty);
+            set => SetValue(IsSaturationValueMaxForcedProperty, value);
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/ColorSlider/ColorSlider.cs

@@ -0,0 +1,399 @@
+using System;
+using Avalonia.Controls.Metadata;
+using Avalonia.Layout;
+using Avalonia.Media;
+using Avalonia.Utilities;
+
+namespace Avalonia.Controls.Primitives
+{
+    /// <summary>
+    /// A slider with a background that represents a single color component.
+    /// </summary>
+    [PseudoClasses(pcDarkSelector, pcLightSelector)]
+    public partial class ColorSlider : Slider
+    {
+        protected const string pcDarkSelector = ":dark-selector";
+        protected const string pcLightSelector = ":light-selector";
+
+        /// <summary>
+        /// Event for when the selected color changes within the slider.
+        /// </summary>
+        public event EventHandler<ColorChangedEventArgs>? ColorChanged;
+
+        private const double MaxHue = 359.99999999999999999; // 17 decimal places
+        private bool disableUpdates = false;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ColorSlider"/> class.
+        /// </summary>
+        public ColorSlider() : base()
+        {
+        }
+
+        /// <summary>
+        /// Updates the visual state of the control by applying latest PseudoClasses.
+        /// </summary>
+        private void UpdatePseudoClasses()
+        {
+            // The slider itself can be transparent for certain color values.
+            // This causes an issue where a white selector thumb over a light window background or
+            // a black selector thumb over a dark window background is not visible.
+            // This means under a certain alpha threshold, neither a white or black selector thumb
+            // should be shown and instead the default slider thumb color should be used instead.
+            if (Color.A < 128 &&
+                (IsAlphaMaxForced == false ||
+                 ColorComponent == ColorComponent.Alpha))
+            {
+                PseudoClasses.Set(pcDarkSelector, false);
+                PseudoClasses.Set(pcLightSelector, false);
+            }
+            else
+            {
+                Color perceivedColor;
+
+                if (ColorModel == ColorModel.Hsva)
+                {
+                    perceivedColor = GetEquivalentBackgroundColor(HsvColor).ToRgb();
+                }
+                else
+                {
+                    perceivedColor = GetEquivalentBackgroundColor(Color);
+                }
+
+                if (ColorHelper.GetRelativeLuminance(perceivedColor) <= 0.5)
+                {
+                    PseudoClasses.Set(pcDarkSelector, false);
+                    PseudoClasses.Set(pcLightSelector, true);
+                }
+                else
+                {
+                    PseudoClasses.Set(pcDarkSelector, true);
+                    PseudoClasses.Set(pcLightSelector, false);
+                }
+            }
+        }
+
+        /// <summary>
+        /// Generates a new background image for the color slider and applies it.
+        /// </summary>
+        private async void UpdateBackground()
+        {
+            // In Avalonia, Bounds returns the actual device-independent pixel size of a control.
+            // However, this is not necessarily the size of the control rendered on a display.
+            // A desktop or application scaling factor may be applied which must be accounted for here.
+            // Remember bitmaps in Avalonia are rendered mapping to actual device pixels, not the device-
+            // independent pixels of controls.
+
+            var scale = LayoutHelper.GetLayoutScale(this);
+            var pixelWidth = Convert.ToInt32(Bounds.Width * scale);
+            var pixelHeight = Convert.ToInt32(Bounds.Height * scale);
+
+            if (pixelWidth != 0 && pixelHeight != 0)
+            {
+                var bitmap = await ColorPickerHelpers.CreateComponentBitmapAsync(
+                    pixelWidth,
+                    pixelHeight,
+                    Orientation,
+                    ColorModel,
+                    ColorComponent,
+                    HsvColor,
+                    IsAlphaMaxForced,
+                    IsSaturationValueMaxForced);
+
+                if (bitmap != null)
+                {
+                    Background = new ImageBrush(ColorPickerHelpers.CreateBitmapFromPixelData(bitmap, pixelWidth, pixelHeight));
+                }
+            }
+        }
+
+        /// <summary>
+        /// Updates the slider property values by applying the current color.
+        /// </summary>
+        /// <remarks>
+        /// Warning: This will trigger property changed updates.
+        /// Consider using <see cref="disableUpdates"/> externally.
+        /// </remarks>
+        private void SetColorToSliderValues()
+        {
+            var hsvColor = HsvColor;
+            var rgbColor = Color;
+            var component = ColorComponent;
+
+            if (ColorModel == ColorModel.Hsva)
+            {
+                // Note: Components converted into a usable range for the user
+                switch (component)
+                {
+                    case ColorComponent.Alpha:
+                        Minimum = 0;
+                        Maximum = 100;
+                        Value   = hsvColor.A * 100;
+                        break;
+                    case ColorComponent.Component1: // Hue
+                        Minimum = 0;
+                        Maximum = MaxHue;
+                        Value   = hsvColor.H;
+                        break;
+                    case ColorComponent.Component2: // Saturation
+                        Minimum = 0;
+                        Maximum = 100;
+                        Value   = hsvColor.S * 100;
+                        break;
+                    case ColorComponent.Component3: // Value
+                        Minimum = 0;
+                        Maximum = 100;
+                        Value   = hsvColor.V * 100;
+                        break;
+                }
+            }
+            else
+            {
+                switch (component)
+                {
+                    case ColorComponent.Alpha:
+                        Minimum = 0;
+                        Maximum = 255;
+                        Value   = Convert.ToDouble(rgbColor.A);
+                        break;
+                    case ColorComponent.Component1: // Red
+                        Minimum = 0;
+                        Maximum = 255;
+                        Value   = Convert.ToDouble(rgbColor.R);
+                        break;
+                    case ColorComponent.Component2: // Green
+                        Minimum = 0;
+                        Maximum = 255;
+                        Value   = Convert.ToDouble(rgbColor.G);
+                        break;
+                    case ColorComponent.Component3: // Blue
+                        Minimum = 0;
+                        Maximum = 255;
+                        Value   = Convert.ToDouble(rgbColor.B);
+                        break;
+                }
+            }
+        }
+
+        /// <summary>
+        /// Gets the current color determined by the slider values.
+        /// </summary>
+        private (Color, HsvColor) GetColorFromSliderValues()
+        {
+            HsvColor hsvColor = new HsvColor();
+            Color rgbColor = new Color();
+            double sliderPercent = Value / (Maximum - Minimum);
+
+            var baseHsvColor = HsvColor;
+            var baseRgbColor = Color;
+            var component = ColorComponent;
+
+            if (ColorModel == ColorModel.Hsva)
+            {
+                switch (component)
+                {
+                    case ColorComponent.Alpha:
+                    {
+                        hsvColor = new HsvColor(sliderPercent, baseHsvColor.H, baseHsvColor.S, baseHsvColor.V);
+                        break;
+                    }
+                    case ColorComponent.Component1:
+                    {
+                        hsvColor = new HsvColor(baseHsvColor.A, sliderPercent * MaxHue, baseHsvColor.S, baseHsvColor.V);
+                        break;
+                    }
+                    case ColorComponent.Component2:
+                    {
+                        hsvColor = new HsvColor(baseHsvColor.A, baseHsvColor.H, sliderPercent, baseHsvColor.V);
+                        break;
+                    }
+                    case ColorComponent.Component3:
+                    {
+                        hsvColor = new HsvColor(baseHsvColor.A, baseHsvColor.H, baseHsvColor.S, sliderPercent);
+                        break;
+                    }
+                }
+
+                return (hsvColor.ToRgb(), hsvColor);
+            }
+            else
+            {
+                byte componentValue = Convert.ToByte(MathUtilities.Clamp(sliderPercent * 255, 0, 255));
+
+                switch (component)
+                {
+                    case ColorComponent.Alpha:
+                        rgbColor = new Color(componentValue, baseRgbColor.R, baseRgbColor.G, baseRgbColor.B);
+                        break;
+                    case ColorComponent.Component1:
+                        rgbColor = new Color(baseRgbColor.A, componentValue, baseRgbColor.G, baseRgbColor.B);
+                        break;
+                    case ColorComponent.Component2:
+                        rgbColor = new Color(baseRgbColor.A, baseRgbColor.R, componentValue, baseRgbColor.B);
+                        break;
+                    case ColorComponent.Component3:
+                        rgbColor = new Color(baseRgbColor.A, baseRgbColor.R, baseRgbColor.G, componentValue);
+                        break;
+                }
+
+                return (rgbColor, rgbColor.ToHsv());
+            }
+        }
+
+        /// <summary>
+        /// Gets the actual background color displayed for the given HSV color.
+        /// This can differ due to the effects of certain properties intended to improve perception.
+        /// </summary>
+        /// <param name="hsvColor">The actual color to get the equivalent background color for.</param>
+        /// <returns>The equivalent, perceived background color.</returns>
+        private HsvColor GetEquivalentBackgroundColor(HsvColor hsvColor)
+        {
+            var component = ColorComponent;
+            var isAlphaMaxForced = IsAlphaMaxForced;
+            var isSaturationValueMaxForced = IsSaturationValueMaxForced;
+
+            if (isAlphaMaxForced &&
+                component != ColorComponent.Alpha)
+            {
+                hsvColor = new HsvColor(1.0, hsvColor.H, hsvColor.S, hsvColor.V);
+            }
+
+            switch (component)
+            {
+                case ColorComponent.Component1:
+                    return new HsvColor(
+                        hsvColor.A,
+                        hsvColor.H,
+                        isSaturationValueMaxForced ? 1.0 : hsvColor.S,
+                        isSaturationValueMaxForced ? 1.0 : hsvColor.V);
+                case ColorComponent.Component2:
+                    return new HsvColor(
+                        hsvColor.A,
+                        hsvColor.H,
+                        hsvColor.S,
+                        isSaturationValueMaxForced ? 1.0 : hsvColor.V);
+                case ColorComponent.Component3:
+                    return new HsvColor(
+                        hsvColor.A,
+                        hsvColor.H,
+                        isSaturationValueMaxForced ? 1.0 : hsvColor.S,
+                        hsvColor.V);
+                default:
+                    return hsvColor;
+            }
+        }
+
+        /// <summary>
+        /// Gets the actual background color displayed for the given RGB color.
+        /// This can differ due to the effects of certain properties intended to improve perception.
+        /// </summary>
+        /// <param name="rgbColor">The actual color to get the equivalent background color for.</param>
+        /// <returns>The equivalent, perceived background color.</returns>
+        private Color GetEquivalentBackgroundColor(Color rgbColor)
+        {
+            var component = ColorComponent;
+            var isAlphaMaxForced = IsAlphaMaxForced;
+
+            if (isAlphaMaxForced &&
+                component != ColorComponent.Alpha)
+            {
+                rgbColor = new Color(255, rgbColor.R, rgbColor.G, rgbColor.B);
+            }
+
+            return rgbColor;
+        }
+
+        /// <inheritdoc/>
+        protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)
+        {
+            if (disableUpdates)
+            {
+                base.OnPropertyChanged(change);
+                return;
+            }
+
+            // Always keep the two color properties in sync
+            if (change.Property == ColorProperty)
+            {
+                disableUpdates = true;
+
+                HsvColor = Color.ToHsv();
+
+                if (IsAutoUpdatingEnabled)
+                {
+                    SetColorToSliderValues();
+                    UpdateBackground();
+                }
+
+                UpdatePseudoClasses();
+                OnColorChanged(new ColorChangedEventArgs(
+                    change.GetOldValue<Color>(),
+                    change.GetNewValue<Color>()));
+
+                disableUpdates = false;
+            }
+            else if (change.Property == HsvColorProperty)
+            {
+                disableUpdates = true;
+
+                Color = HsvColor.ToRgb();
+
+                if (IsAutoUpdatingEnabled)
+                {
+                    SetColorToSliderValues();
+                    UpdateBackground();
+                }
+
+                UpdatePseudoClasses();
+                OnColorChanged(new ColorChangedEventArgs(
+                    change.GetOldValue<HsvColor>().ToRgb(),
+                    change.GetNewValue<HsvColor>().ToRgb()));
+
+                disableUpdates = false;
+            }
+            else if (change.Property == BoundsProperty)
+            {
+                if (IsAutoUpdatingEnabled)
+                {
+                    UpdateBackground();
+                }
+            }
+            else if (change.Property == ValueProperty ||
+                     change.Property == MinimumProperty ||
+                     change.Property == MaximumProperty)
+            {
+                disableUpdates = true;
+
+                Color oldColor = Color;
+                (var color, var hsvColor) = GetColorFromSliderValues();
+
+                if (ColorModel == ColorModel.Hsva)
+                {
+                    HsvColor = hsvColor;
+                    Color = hsvColor.ToRgb();
+                }
+                else
+                {
+                    Color = color;
+                    HsvColor = color.ToHsv();
+                }
+
+                UpdatePseudoClasses();
+                OnColorChanged(new ColorChangedEventArgs(oldColor, Color));
+
+                disableUpdates = false;
+            }
+
+            base.OnPropertyChanged(change);
+        }
+
+        /// <summary>
+        /// Called before the <see cref="ColorChanged"/> event occurs.
+        /// </summary>
+        /// <param name="e">The <see cref="ColorChangedEventArgs"/> defining old/new colors.</param>
+        protected virtual void OnColorChanged(ColorChangedEventArgs e)
+        {
+            ColorChanged?.Invoke(this, e);
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/ColorSpectrum/ColorHelpers.cs

@@ -1,414 +0,0 @@
-// This source file is adapted from the WinUI project.
-// (https://github.com/microsoft/microsoft-ui-xaml)
-//
-// Licensed to The Avalonia Project under the MIT License.
-
-using System;
-using System.Collections.Generic;
-using System.Runtime.InteropServices;
-using Avalonia.Media;
-using Avalonia.Media.Imaging;
-using Avalonia.Platform;
-
-namespace Avalonia.Controls.Primitives
-{
-    internal static class ColorHelpers
-    {
-        public const int CheckerSize = 4;
-
-        public static bool ToDisplayNameExists
-        {
-            get => false;
-        }
-
-        public static string ToDisplayName(Color color)
-        {
-            return string.Empty;
-        }
-
-        public static Hsv IncrementColorComponent(
-            Hsv originalHsv,
-            HsvComponent component,
-            IncrementDirection direction,
-            IncrementAmount amount,
-            bool shouldWrap,
-            double minBound,
-            double maxBound)
-        {
-            Hsv newHsv = originalHsv;
-
-            if (amount == IncrementAmount.Small || !ToDisplayNameExists)
-            {
-                // In order to avoid working with small values that can incur rounding issues,
-                // we'll multiple saturation and value by 100 to put them in the range of 0-100 instead of 0-1.
-                newHsv.S *= 100;
-                newHsv.V *= 100;
-
-                // Note: *valueToIncrement replaced with ref local variable for C#, must be initialized
-                ref double valueToIncrement = ref newHsv.H;
-                double incrementAmount = 0.0;
-
-                // If we're adding a small increment, then we'll just add or subtract 1.
-                // If we're adding a large increment, then we want to snap to the next
-                // or previous major value - for hue, this is every increment of 30;
-                // for saturation and value, this is every increment of 10.
-                switch (component)
-                {
-                    case HsvComponent.Hue:
-                        valueToIncrement = ref newHsv.H;
-                        incrementAmount = amount == IncrementAmount.Small ? 1 : 30;
-                        break;
-
-                    case HsvComponent.Saturation:
-                        valueToIncrement = ref newHsv.S;
-                        incrementAmount = amount == IncrementAmount.Small ? 1 : 10;
-                        break;
-
-                    case HsvComponent.Value:
-                        valueToIncrement = ref newHsv.V;
-                        incrementAmount = amount == IncrementAmount.Small ? 1 : 10;
-                        break;
-
-                    default:
-                        throw new InvalidOperationException("Invalid HsvComponent.");
-                }
-
-                double previousValue = valueToIncrement;
-
-                valueToIncrement += (direction == IncrementDirection.Lower ? -incrementAmount : incrementAmount);
-
-                // If the value has reached outside the bounds, we were previous at the boundary, and we should wrap,
-                // then we'll place the selection on the other side of the spectrum.
-                // Otherwise, we'll place it on the boundary that was exceeded.
-                if (valueToIncrement < minBound)
-                {
-                    valueToIncrement = (shouldWrap && previousValue == minBound) ? maxBound : minBound;
-                }
-
-                if (valueToIncrement > maxBound)
-                {
-                    valueToIncrement = (shouldWrap && previousValue == maxBound) ? minBound : maxBound;
-                }
-
-                // We multiplied saturation and value by 100 previously, so now we want to put them back in the 0-1 range.
-                newHsv.S /= 100;
-                newHsv.V /= 100;
-            }
-            else
-            {
-                // While working with named colors, we're going to need to be working in actual HSV units,
-                // so we'll divide the min bound and max bound by 100 in the case of saturation or value,
-                // since we'll have received units between 0-100 and we need them within 0-1.
-                if (component == HsvComponent.Saturation ||
-                    component == HsvComponent.Value)
-                {
-                    minBound /= 100;
-                    maxBound /= 100;
-                }
-
-                newHsv = FindNextNamedColor(originalHsv, component, direction, shouldWrap, minBound, maxBound);
-            }
-
-            return newHsv;
-        }
-
-        public static Hsv FindNextNamedColor(
-            Hsv originalHsv,
-            HsvComponent component,
-            IncrementDirection direction,
-            bool shouldWrap,
-            double minBound,
-            double maxBound)
-        {
-            // There's no easy way to directly get the next named color, so what we'll do
-            // is just iterate in the direction that we want to find it until we find a color
-            // in that direction that has a color name different than our current color name.
-            // Once we find a new color name, then we'll iterate across that color name until
-            // we find its bounds on the other side, and then select the color that is exactly
-            // in the middle of that color's bounds.
-            Hsv newHsv = originalHsv;
-            
-            string originalColorName = ColorHelpers.ToDisplayName(originalHsv.ToRgb().ToColor());
-            string newColorName = originalColorName;
-
-            // Note: *newValue replaced with ref local variable for C#, must be initialized
-            double originalValue = 0.0;
-            ref double newValue = ref newHsv.H;
-            double incrementAmount = 0.0;
-
-            switch (component)
-            {
-                case HsvComponent.Hue:
-                    originalValue = originalHsv.H;
-                    newValue = ref newHsv.H;
-                    incrementAmount = 1;
-                    break;
-
-                case HsvComponent.Saturation:
-                    originalValue = originalHsv.S;
-                    newValue = ref newHsv.S;
-                    incrementAmount = 0.01;
-                    break;
-
-                case HsvComponent.Value:
-                    originalValue = originalHsv.V;
-                    newValue = ref newHsv.V;
-                    incrementAmount = 0.01;
-                    break;
-
-                default:
-                    throw new InvalidOperationException("Invalid HsvComponent.");
-            }
-
-            bool shouldFindMidPoint = true;
-
-            while (newColorName == originalColorName)
-            {
-                double previousValue = newValue;
-                newValue += (direction == IncrementDirection.Lower ? -1 : 1) * incrementAmount;
-
-                bool justWrapped = false;
-
-                // If we've hit a boundary, then either we should wrap or we shouldn't.
-                // If we should, then we'll perform that wrapping if we were previously up against
-                // the boundary that we've now hit.  Otherwise, we'll stop at that boundary.
-                if (newValue > maxBound)
-                {
-                    if (shouldWrap)
-                    {
-                        newValue = minBound;
-                        justWrapped = true;
-                    }
-                    else
-                    {
-                        newValue = maxBound;
-                        shouldFindMidPoint = false;
-                        newColorName = ColorHelpers.ToDisplayName(newHsv.ToRgb().ToColor());
-                        break;
-                    }
-                }
-                else if (newValue < minBound)
-                {
-                    if (shouldWrap)
-                    {
-                        newValue = maxBound;
-                        justWrapped = true;
-                    }
-                    else
-                    {
-                        newValue = minBound;
-                        shouldFindMidPoint = false;
-                        newColorName = ColorHelpers.ToDisplayName(newHsv.ToRgb().ToColor());
-                        break;
-                    }
-                }
-
-                if (!justWrapped &&
-                    previousValue != originalValue &&
-                    Math.Sign(newValue - originalValue) != Math.Sign(previousValue - originalValue))
-                {
-                    // If we've wrapped all the way back to the start and have failed to find a new color name,
-                    // then we'll just quit - there isn't a new color name that we're going to find.
-                    shouldFindMidPoint = false;
-                    break;
-                }
-
-                newColorName = ColorHelpers.ToDisplayName(newHsv.ToRgb().ToColor());
-            }
-
-            if (shouldFindMidPoint)
-            {
-                Hsv startHsv = newHsv;
-                Hsv currentHsv = startHsv;
-                double startEndOffset = 0;
-                string currentColorName = newColorName;
-
-                // Note: *startValue/*currentValue replaced with ref local variables for C#, must be initialized
-                ref double startValue = ref startHsv.H;
-                ref double currentValue = ref currentHsv.H;
-                double wrapIncrement = 0;
-
-                switch (component)
-                {
-                    case HsvComponent.Hue:
-                        startValue = ref startHsv.H;
-                        currentValue = ref currentHsv.H;
-                        wrapIncrement = 360.0;
-                        break;
-
-                    case HsvComponent.Saturation:
-                        startValue = ref startHsv.S;
-                        currentValue = ref currentHsv.S;
-                        wrapIncrement = 1.0;
-                        break;
-
-                    case HsvComponent.Value:
-                        startValue = ref startHsv.V;
-                        currentValue = ref currentHsv.V;
-                        wrapIncrement = 1.0;
-                        break;
-
-                    default:
-                        throw new InvalidOperationException("Invalid HsvComponent.");
-                }
-
-                while (newColorName == currentColorName)
-                {
-                    currentValue += (direction == IncrementDirection.Lower ? -1 : 1) * incrementAmount;
-
-                    // If we've hit a boundary, then either we should wrap or we shouldn't.
-                    // If we should, then we'll perform that wrapping if we were previously up against
-                    // the boundary that we've now hit.  Otherwise, we'll stop at that boundary.
-                    if (currentValue > maxBound)
-                    {
-                        if (shouldWrap)
-                        {
-                            currentValue = minBound;
-                            startEndOffset = maxBound - minBound;
-                        }
-                        else
-                        {
-                            currentValue = maxBound;
-                            break;
-                        }
-                    }
-                    else if (currentValue < minBound)
-                    {
-                        if (shouldWrap)
-                        {
-                            currentValue = maxBound;
-                            startEndOffset = minBound - maxBound;
-                        }
-                        else
-                        {
-                            currentValue = minBound;
-                            break;
-                        }
-                    }
-
-                    currentColorName = ColorHelpers.ToDisplayName(currentHsv.ToRgb().ToColor());
-                }
-
-                newValue = (startValue + currentValue + startEndOffset) / 2;
-
-                // Dividing by 2 may have gotten us halfway through a single step, so we'll
-                // remove that half-step if it exists.
-                double leftoverValue = Math.Abs(newValue);
-
-                while (leftoverValue > incrementAmount)
-                {
-                    leftoverValue -= incrementAmount;
-                }
-
-                newValue -= leftoverValue;
-
-                while (newValue < minBound)
-                {
-                    newValue += wrapIncrement;
-                }
-
-                while (newValue > maxBound)
-                {
-                    newValue -= wrapIncrement;
-                }
-            }
-
-            return newHsv;
-        }
-
-        public static double IncrementAlphaComponent(
-            double originalAlpha,
-            IncrementDirection direction,
-            IncrementAmount amount,
-            bool shouldWrap,
-            double minBound,
-            double maxBound)
-        {
-            // In order to avoid working with small values that can incur rounding issues,
-            // we'll multiple alpha by 100 to put it in the range of 0-100 instead of 0-1.
-            originalAlpha *= 100;
-
-            const double smallIncrementAmount = 1;
-            const double largeIncrementAmount = 10;
-
-            if (amount == IncrementAmount.Small)
-            {
-                originalAlpha += (direction == IncrementDirection.Lower ? -1 : 1) * smallIncrementAmount;
-            }
-            else
-            {
-                if (direction == IncrementDirection.Lower)
-                {
-                    originalAlpha = Math.Ceiling((originalAlpha - largeIncrementAmount) / largeIncrementAmount) * largeIncrementAmount;
-                }
-                else
-                {
-                    originalAlpha = Math.Floor((originalAlpha + largeIncrementAmount) / largeIncrementAmount) * largeIncrementAmount;
-                }
-            }
-
-            // If the value has reached outside the bounds and we should wrap, then we'll place the selection
-            // on the other side of the spectrum.  Otherwise, we'll place it on the boundary that was exceeded.
-            if (originalAlpha < minBound)
-            {
-                originalAlpha = shouldWrap ? maxBound : minBound;
-            }
-
-            if (originalAlpha > maxBound)
-            {
-                originalAlpha = shouldWrap ? minBound : maxBound;
-            }
-
-            // We multiplied alpha by 100 previously, so now we want to put it back in the 0-1 range.
-            return originalAlpha / 100;
-        }
-
-        public static WriteableBitmap CreateBitmapFromPixelData(
-            int pixelWidth,
-            int pixelHeight,
-            List<byte> bgraPixelData)
-        {
-            Vector dpi = new Vector(96, 96); // Standard may need to change on some devices
-
-            WriteableBitmap bitmap = new WriteableBitmap(
-                new PixelSize(pixelWidth, pixelHeight),
-                dpi,
-                PixelFormat.Bgra8888,
-                AlphaFormat.Premul);
-
-            // Warning: This is highly questionable
-            using (var frameBuffer = bitmap.Lock())
-            {
-                Marshal.Copy(bgraPixelData.ToArray(), 0, frameBuffer.Address, bgraPixelData.Count);
-            }
-
-            return bitmap;
-        }
-
-        /// <summary>
-        /// Gets the relative (perceptual) luminance/brightness of the given color.
-        /// 1 is closer to white while 0 is closer to black.
-        /// </summary>
-        /// <param name="color">The color to calculate relative luminance for.</param>
-        /// <returns>The relative (perceptual) luminance/brightness of the given color.</returns>
-        public static double GetRelativeLuminance(Color color)
-        {
-            // The equation for relative luminance is given by
-            //
-            // L = 0.2126 * Rg + 0.7152 * Gg + 0.0722 * Bg
-            //
-            // where Xg = { X/3294 if X <= 10, (R/269 + 0.0513)^2.4 otherwise }
-            //
-            // If L is closer to 1, then the color is closer to white; if it is closer to 0,
-            // then the color is closer to black.  This is based on the fact that the human
-            // eye perceives green to be much brighter than red, which in turn is perceived to be
-            // brighter than blue.
-
-            double rg = color.R <= 10 ? color.R / 3294.0 : Math.Pow(color.R / 269.0 + 0.0513, 2.4);
-            double gg = color.G <= 10 ? color.G / 3294.0 : Math.Pow(color.G / 269.0 + 0.0513, 2.4);
-            double bg = color.B <= 10 ? color.B / 3294.0 : Math.Pow(color.B / 269.0 + 0.0513, 2.4);
-
-            return (0.2126 * rg + 0.7152 * gg + 0.0722 * bg);
-        }
-    }
-}

src/Avalonia.Controls.ColorPicker/ColorSpectrum/ColorSpectrum.Properties.cs

@@ -3,6 +3,7 @@
 //
 // Licensed to The Avalonia Project under the MIT License.
 
+using Avalonia.Data;
 using Avalonia.Media;
 
 namespace Avalonia.Controls.Primitives
@@ -10,6 +11,88 @@ namespace Avalonia.Controls.Primitives
     /// <inheritdoc/>
     public partial class ColorSpectrum
     {
+        /// <summary>
+        /// Defines the <see cref="Color"/> property.
+        /// </summary>
+        public static readonly StyledProperty<Color> ColorProperty =
+            AvaloniaProperty.Register<ColorSpectrum, Color>(
+                nameof(Color),
+                Colors.White,
+                defaultBindingMode: BindingMode.TwoWay);
+
+        /// <summary>
+        /// Defines the <see cref="Components"/> property.
+        /// </summary>
+        public static readonly StyledProperty<ColorSpectrumComponents> ComponentsProperty =
+            AvaloniaProperty.Register<ColorSpectrum, ColorSpectrumComponents>(
+                nameof(Components),
+                ColorSpectrumComponents.HueSaturation);
+
+        /// <summary>
+        /// Defines the <see cref="HsvColor"/> property.
+        /// </summary>
+        public static readonly StyledProperty<HsvColor> HsvColorProperty =
+            AvaloniaProperty.Register<ColorSpectrum, HsvColor>(
+                nameof(HsvColor),
+                Colors.White.ToHsv(),
+                defaultBindingMode: BindingMode.TwoWay);
+
+        /// <summary>
+        /// Defines the <see cref="MaxHue"/> property.
+        /// </summary>
+        public static readonly StyledProperty<int> MaxHueProperty =
+            AvaloniaProperty.Register<ColorSpectrum, int>(
+                nameof(MaxHue),
+                359);
+
+        /// <summary>
+        /// Defines the <see cref="MaxSaturation"/> property.
+        /// </summary>
+        public static readonly StyledProperty<int> MaxSaturationProperty =
+            AvaloniaProperty.Register<ColorSpectrum, int>(
+                nameof(MaxSaturation),
+                100);
+
+        /// <summary>
+        /// Defines the <see cref="MaxValue"/> property.
+        /// </summary>
+        public static readonly StyledProperty<int> MaxValueProperty =
+            AvaloniaProperty.Register<ColorSpectrum, int>(
+                nameof(MaxValue),
+                100);
+
+        /// <summary>
+        /// Defines the <see cref="MinHue"/> property.
+        /// </summary>
+        public static readonly StyledProperty<int> MinHueProperty =
+            AvaloniaProperty.Register<ColorSpectrum, int>(
+                nameof(MinHue),
+                0);
+
+        /// <summary>
+        /// Defines the <see cref="MinSaturation"/> property.
+        /// </summary>
+        public static readonly StyledProperty<int> MinSaturationProperty =
+            AvaloniaProperty.Register<ColorSpectrum, int>(
+                nameof(MinSaturation),
+                0);
+
+        /// <summary>
+        /// Defines the <see cref="MinValue"/> property.
+        /// </summary>
+        public static readonly StyledProperty<int> MinValueProperty =
+            AvaloniaProperty.Register<ColorSpectrum, int>(
+                nameof(MinValue),
+                0);
+
+        /// <summary>
+        /// Defines the <see cref="Shape"/> property.
+        /// </summary>
+        public static readonly StyledProperty<ColorSpectrumShape> ShapeProperty =
+            AvaloniaProperty.Register<ColorSpectrum, ColorSpectrumShape>(
+                nameof(Shape),
+                ColorSpectrumShape.Box);
+
         /// <summary>
         /// Gets or sets the currently selected color in the RGB color model.
         /// </summary>
@@ -23,14 +106,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(ColorProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="Color"/> property.
-        /// </summary>
-        public static readonly StyledProperty<Color> ColorProperty =
-            AvaloniaProperty.Register<ColorSpectrum, Color>(
-                nameof(Color),
-                Color.FromArgb(0xFF, 0xFF, 0xFF, 0xFF));
-
         /// <summary>
         /// Gets or sets the two HSV color components displayed by the spectrum.
         /// </summary>
@@ -43,14 +118,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(ComponentsProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="Components"/> property.
-        /// </summary>
-        public static readonly StyledProperty<ColorSpectrumComponents> ComponentsProperty =
-            AvaloniaProperty.Register<ColorSpectrum, ColorSpectrumComponents>(
-                nameof(Components),
-                ColorSpectrumComponents.HueSaturation);
-
         /// <summary>
         /// Gets or sets the currently selected color in the HSV color model.
         /// </summary>
@@ -65,14 +132,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(HsvColorProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="HsvColor"/> property.
-        /// </summary>
-        public static readonly StyledProperty<HsvColor> HsvColorProperty =
-            AvaloniaProperty.Register<ColorSpectrum, HsvColor>(
-                nameof(HsvColor),
-                new HsvColor(1, 0, 0, 1));
-
         /// <summary>
         /// Gets or sets the maximum value of the Hue component in the range from 0..359.
         /// This property must be greater than <see cref="MinHue"/>.
@@ -86,12 +145,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(MaxHueProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="MaxHue"/> property.
-        /// </summary>
-        public static readonly StyledProperty<int> MaxHueProperty =
-            AvaloniaProperty.Register<ColorSpectrum, int>(nameof(MaxHue), 359);
-
         /// <summary>
         /// Gets or sets the maximum value of the Saturation component in the range from 0..100.
         /// This property must be greater than <see cref="MinSaturation"/>.
@@ -105,12 +158,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(MaxSaturationProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="MaxSaturation"/> property.
-        /// </summary>
-        public static readonly StyledProperty<int> MaxSaturationProperty =
-            AvaloniaProperty.Register<ColorSpectrum, int>(nameof(MaxSaturation), 100);
-
         /// <summary>
         /// Gets or sets the maximum value of the Value component in the range from 0..100.
         /// This property must be greater than <see cref="MinValue"/>.
@@ -124,12 +171,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(MaxValueProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="MaxValue"/> property.
-        /// </summary>
-        public static readonly StyledProperty<int> MaxValueProperty =
-            AvaloniaProperty.Register<ColorSpectrum, int>(nameof(MaxValue), 100);
-
         /// <summary>
         /// Gets or sets the minimum value of the Hue component in the range from 0..359.
         /// This property must be less than <see cref="MaxHue"/>.
@@ -143,12 +184,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(MinHueProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="MinHue"/> property.
-        /// </summary>
-        public static readonly StyledProperty<int> MinHueProperty =
-            AvaloniaProperty.Register<ColorSpectrum, int>(nameof(MinHue), 0);
-
         /// <summary>
         /// Gets or sets the minimum value of the Saturation component in the range from 0..100.
         /// This property must be less than <see cref="MaxSaturation"/>.
@@ -162,12 +197,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(MinSaturationProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="MinSaturation"/> property.
-        /// </summary>
-        public static readonly StyledProperty<int> MinSaturationProperty =
-            AvaloniaProperty.Register<ColorSpectrum, int>(nameof(MinSaturation), 0);
-
         /// <summary>
         /// Gets or sets the minimum value of the Value component in the range from 0..100.
         /// This property must be less than <see cref="MaxValue"/>.
@@ -181,12 +210,6 @@ namespace Avalonia.Controls.Primitives
             set => SetValue(MinValueProperty, value);
         }
 
-        /// <summary>
-        /// Defines the <see cref="MinValue"/> property.
-        /// </summary>
-        public static readonly StyledProperty<int> MinValueProperty =
-            AvaloniaProperty.Register<ColorSpectrum, int>(nameof(MinValue), 0);
-
         /// <summary>
         /// Gets or sets the displayed shape of the spectrum.
         /// </summary>
@@ -195,13 +218,5 @@ namespace Avalonia.Controls.Primitives
             get => GetValue(ShapeProperty);
             set => SetValue(ShapeProperty, value);
         }
-
-        /// <summary>
-        /// Defines the <see cref="Shape"/> property.
-        /// </summary>
-        public static readonly StyledProperty<ColorSpectrumShape> ShapeProperty =
-            AvaloniaProperty.Register<ColorSpectrum, ColorSpectrumShape>(
-                nameof(Shape),
-                ColorSpectrumShape.Box);
     }
 }

src/Avalonia.Controls.ColorPicker/ColorSpectrum/ColorSpectrum.cs

@@ -10,6 +10,7 @@ using Avalonia.Controls.Metadata;
 using Avalonia.Controls.Shapes;
 using Avalonia.Input;
 using Avalonia.Interactivity;
+using Avalonia.Layout;
 using Avalonia.Media;
 using Avalonia.Media.Imaging;
 using Avalonia.Threading;
@@ -20,7 +21,6 @@ namespace Avalonia.Controls.Primitives
     /// <summary>
     /// A two dimensional spectrum for color selection.
     /// </summary>
-    [TemplatePart("PART_ColorNameToolTip",         typeof(ToolTip))]
     [TemplatePart("PART_InputTarget",              typeof(Canvas))]
     [TemplatePart("PART_LayoutRoot",               typeof(Panel))]
     [TemplatePart("PART_SelectionEllipsePanel",    typeof(Panel))]
@@ -29,10 +29,11 @@ namespace Avalonia.Controls.Primitives
     [TemplatePart("PART_SpectrumRectangle",        typeof(Rectangle))]
     [TemplatePart("PART_SpectrumOverlayEllipse",   typeof(Ellipse))]
     [TemplatePart("PART_SpectrumOverlayRectangle", typeof(Rectangle))]
-    [PseudoClasses(pcPressed, pcLargeSelector, pcLightSelector)]
+    [PseudoClasses(pcPressed, pcLargeSelector, pcDarkSelector, pcLightSelector)]
     public partial class ColorSpectrum : TemplatedControl
     {
         protected const string pcPressed       = ":pressed";
+        protected const string pcDarkSelector  = ":dark-selector";
         protected const string pcLargeSelector = ":large-selector";
         protected const string pcLightSelector = ":light-selector";
 
@@ -60,7 +61,6 @@ namespace Avalonia.Controls.Primitives
         private Ellipse? _spectrumOverlayEllipse;
         private Canvas? _inputTarget;
         private Panel? _selectionEllipsePanel;
-        private ToolTip? _colorNameToolTip;
 
         // Put the spectrum images in a bitmap, which is then given to an ImageBrush.
         private WriteableBitmap? _hueRedBitmap;
@@ -117,7 +117,6 @@ namespace Avalonia.Controls.Primitives
 
             UnregisterEvents(); // Failsafe
 
-            _colorNameToolTip = e.NameScope.Find<ToolTip>("PART_ColorNameToolTip");
             _inputTarget = e.NameScope.Find<Canvas>("PART_InputTarget");
             _layoutRoot = e.NameScope.Find<Panel>("PART_LayoutRoot");
             _selectionEllipsePanel = e.NameScope.Find<Panel>("PART_SelectionEllipsePanel");
@@ -152,10 +151,10 @@ namespace Avalonia.Controls.Primitives
                 });
             }
 
-            if (ColorHelpers.ToDisplayNameExists &&
-                _colorNameToolTip != null)
+            if (_selectionEllipsePanel != null &&
+                ColorHelper.ToDisplayNameExists)
             {
-                _colorNameToolTip.Content = ColorHelpers.ToDisplayName(Color);
+                ToolTip.SetTip(_selectionEllipsePanel, ColorHelper.ToDisplayName(Color));
             }
 
             // If we haven't yet created our bitmaps, do so now.
@@ -320,7 +319,7 @@ namespace Avalonia.Controls.Primitives
             IncrementAmount amount = isControlDown ? IncrementAmount.Large : IncrementAmount.Small;
 
             HsvColor hsvColor = HsvColor;
-            UpdateColor(ColorHelpers.IncrementColorComponent(
+            UpdateColor(ColorPickerHelpers.IncrementColorComponent(
                 new Hsv(hsvColor),
                 incrementComponent,
                 direction,
@@ -330,34 +329,51 @@ namespace Avalonia.Controls.Primitives
                 maxBound));
 
             e.Handled = true;
-
-            return;
         }
 
         /// <inheritdoc/>
         protected override void OnGotFocus(GotFocusEventArgs e)
         {
             // We only want to bother with the color name tool tip if we can provide color names.
-            if (_colorNameToolTip != null &&
-                ColorHelpers.ToDisplayNameExists)
+            if (_selectionEllipsePanel != null &&
+                ColorHelper.ToDisplayNameExists)
             {
-                ToolTip.SetIsOpen(_colorNameToolTip, true);
+                ToolTip.SetIsOpen(_selectionEllipsePanel, true);
             }
 
             UpdatePseudoClasses();
+
+            base.OnGotFocus(e);
         }
 
         /// <inheritdoc/>
         protected override void OnLostFocus(RoutedEventArgs e)
         {
             // We only want to bother with the color name tool tip if we can provide color names.
-            if (_colorNameToolTip != null &&
-                ColorHelpers.ToDisplayNameExists)
+            if (_selectionEllipsePanel != null &&
+                ColorHelper.ToDisplayNameExists)
             {
-                ToolTip.SetIsOpen(_colorNameToolTip, false);
+                ToolTip.SetIsOpen(_selectionEllipsePanel, false);
             }
 
             UpdatePseudoClasses();
+
+            base.OnLostFocus(e);
+        }
+
+        /// <inheritdoc/>
+        protected override void OnPointerLeave(PointerEventArgs e)
+        {
+            // We only want to bother with the color name tool tip if we can provide color names.
+            if (_selectionEllipsePanel != null &&
+                ColorHelper.ToDisplayNameExists)
+            {
+                ToolTip.SetIsOpen(_selectionEllipsePanel, false);
+            }
+
+            UpdatePseudoClasses();
+
+            base.OnPointerLeave(e);
         }
 
         /// <inheritdoc/>
@@ -516,12 +532,10 @@ namespace Avalonia.Controls.Primitives
                 var colorChangedEventArgs = new ColorChangedEventArgs(_oldColor, newColor);
                 ColorChanged?.Invoke(this, colorChangedEventArgs);
 
-                if (ColorHelpers.ToDisplayNameExists)
+                if (_selectionEllipsePanel != null &&
+                    ColorHelper.ToDisplayNameExists)
                 {
-                    if (_colorNameToolTip != null)
-                    {
-                        _colorNameToolTip.Content = ColorHelpers.ToDisplayName(newColor);
-                    }
+                    ToolTip.SetTip(_selectionEllipsePanel, ColorHelper.ToDisplayName(Color));
                 }
             }
         }
@@ -543,7 +557,16 @@ namespace Avalonia.Controls.Primitives
                 PseudoClasses.Set(pcLargeSelector, false);
             }
 
-            PseudoClasses.Set(pcLightSelector, SelectionEllipseShouldBeLight());
+            if (SelectionEllipseShouldBeLight())
+            {
+                PseudoClasses.Set(pcDarkSelector, false);
+                PseudoClasses.Set(pcLightSelector, true);
+            }
+            else
+            {
+                PseudoClasses.Set(pcDarkSelector, true);
+                PseudoClasses.Set(pcLightSelector, false);
+            }
         }
 
         private void UpdateColor(Hsv newHsv)
@@ -575,8 +598,10 @@ namespace Avalonia.Controls.Primitives
                 return;
             }
 
-            double xPosition = point.Position.X;
-            double yPosition = point.Position.Y;
+            // Remember the bitmap size follows physical device pixels
+            var scale = LayoutHelper.GetLayoutScale(this);
+            double xPosition = point.Position.X * scale;
+            double yPosition = point.Position.Y * scale;
             double radius = Math.Min(_imageWidthFromLastBitmapCreation, _imageHeightFromLastBitmapCreation) / 2;
             double distanceFromRadius = Math.Sqrt(Math.Pow(xPosition - radius, 2) + Math.Pow(yPosition - radius, 2));
 
@@ -807,19 +832,17 @@ namespace Avalonia.Controls.Primitives
                 yPosition = (Math.Sin((thetaValue * Math.PI / 180.0) + Math.PI) * radius * rValue) + radius;
             }
 
-            Canvas.SetLeft(_selectionEllipsePanel, xPosition - (_selectionEllipsePanel.Width / 2));
-            Canvas.SetTop(_selectionEllipsePanel, yPosition - (_selectionEllipsePanel.Height / 2));
+            // Remember the bitmap size follows physical device pixels
+            var scale = LayoutHelper.GetLayoutScale(this);
+            Canvas.SetLeft(_selectionEllipsePanel, (xPosition / scale) - (_selectionEllipsePanel.Width / 2));
+            Canvas.SetTop(_selectionEllipsePanel, (yPosition / scale) - (_selectionEllipsePanel.Height / 2));
 
             // We only want to bother with the color name tool tip if we can provide color names.
-            if (ColorHelpers.ToDisplayNameExists)
+            if (IsFocused &&
+                _selectionEllipsePanel != null &&
+                ColorHelper.ToDisplayNameExists)
             {
-                if (_colorNameToolTip != null)
-                {
-                    // ToolTip doesn't currently provide any way to re-run its placement logic if its placement target moves,
-                    // so toggling IsEnabled induces it to do that without incurring any visual glitches.
-                    _colorNameToolTip.IsEnabled = false;
-                    _colorNameToolTip.IsEnabled = true;
-                }
+                ToolTip.SetIsOpen(_selectionEllipsePanel, true);
             }
 
             UpdatePseudoClasses();
@@ -961,7 +984,14 @@ namespace Avalonia.Controls.Primitives
             List<byte> bgraMaxPixelData = new List<byte>();
             List<Hsv> newHsvValues = new List<Hsv>();
 
-            var pixelCount = (int)(Math.Round(minDimension) * Math.Round(minDimension));
+            // In Avalonia, Bounds returns the actual device-independent pixel size of a control.
+            // However, this is not necessarily the size of the control rendered on a display.
+            // A desktop or application scaling factor may be applied which must be accounted for here.
+            // Remember bitmaps in Avalonia are rendered mapping to actual device pixels, not the device-
+            // independent pixels of controls.
+            var scale = LayoutHelper.GetLayoutScale(this);
+            int pixelDimension = (int)Math.Round(minDimension * scale);
+            var pixelCount = pixelDimension * pixelDimension;
             var pixelDataSize = pixelCount * 4;
             bgraMinPixelData.Capacity = pixelDataSize;
 
@@ -978,8 +1008,6 @@ namespace Avalonia.Controls.Primitives
             bgraMaxPixelData.Capacity = pixelDataSize;
             newHsvValues.Capacity = pixelCount;
 
-            int minDimensionInt = (int)Math.Round(minDimension);
-
             await Task.Run(() =>
             {
                 // As the user perceives it, every time the third dimension not represented in the ColorSpectrum changes,
@@ -998,12 +1026,12 @@ namespace Avalonia.Controls.Primitives
                 // but the running time savings after that are *huge* when we can just set an opacity instead of generating a brand new bitmap.
                 if (shape == ColorSpectrumShape.Box)
                 {
-                    for (int x = minDimensionInt - 1; x >= 0; --x)
+                    for (int x = pixelDimension - 1; x >= 0; --x)
                     {
-                        for (int y = minDimensionInt - 1; y >= 0; --y)
+                        for (int y = pixelDimension - 1; y >= 0; --y)
                         {
                             FillPixelForBox(
-                                x, y, hsv, minDimensionInt, components, minHue, maxHue, minSaturation, maxSaturation, minValue, maxValue,
+                                x, y, hsv, pixelDimension, components, minHue, maxHue, minSaturation, maxSaturation, minValue, maxValue,
                                 bgraMinPixelData, bgraMiddle1PixelData, bgraMiddle2PixelData, bgraMiddle3PixelData, bgraMiddle4PixelData, bgraMaxPixelData,
                                 newHsvValues);
                         }
@@ -1011,12 +1039,12 @@ namespace Avalonia.Controls.Primitives
                 }
                 else
                 {
-                    for (int y = 0; y < minDimensionInt; ++y)
+                    for (int y = 0; y < pixelDimension; ++y)
                     {
-                        for (int x = 0; x < minDimensionInt; ++x)
+                        for (int x = 0; x < pixelDimension; ++x)
                         {
                             FillPixelForRing(
-                                x, y, minDimensionInt / 2.0, hsv, components, minHue, maxHue, minSaturation, maxSaturation, minValue, maxValue,
+                                x, y, pixelDimension / 2.0, hsv, components, minHue, maxHue, minSaturation, maxSaturation, minValue, maxValue,
                                 bgraMinPixelData, bgraMiddle1PixelData, bgraMiddle2PixelData, bgraMiddle3PixelData, bgraMiddle4PixelData, bgraMaxPixelData,
                                 newHsvValues);
                         }
@@ -1026,13 +1054,13 @@ namespace Avalonia.Controls.Primitives
 
             Dispatcher.UIThread.Post(() =>
             {
-                int pixelWidth = (int)Math.Round(minDimension);
-                int pixelHeight = (int)Math.Round(minDimension);
+                int pixelWidth = pixelDimension;
+                int pixelHeight = pixelDimension;
 
                 ColorSpectrumComponents components2 = Components;
 
-                WriteableBitmap minBitmap = ColorHelpers.CreateBitmapFromPixelData(pixelWidth, pixelHeight, bgraMinPixelData);
-                WriteableBitmap maxBitmap = ColorHelpers.CreateBitmapFromPixelData(pixelWidth, pixelHeight, bgraMaxPixelData);
+                WriteableBitmap minBitmap = ColorPickerHelpers.CreateBitmapFromPixelData(bgraMinPixelData, pixelWidth, pixelHeight);
+                WriteableBitmap maxBitmap = ColorPickerHelpers.CreateBitmapFromPixelData(bgraMaxPixelData, pixelWidth, pixelHeight);
 
                 switch (components2)
                 {
@@ -1048,18 +1076,18 @@ namespace Avalonia.Controls.Primitives
                     case ColorSpectrumComponents.ValueSaturation:
                     case ColorSpectrumComponents.SaturationValue:
                         _hueRedBitmap = minBitmap;
-                        _hueYellowBitmap = ColorHelpers.CreateBitmapFromPixelData(pixelWidth, pixelHeight, bgraMiddle1PixelData);
-                        _hueGreenBitmap = ColorHelpers.CreateBitmapFromPixelData(pixelWidth, pixelHeight, bgraMiddle2PixelData);
-                        _hueCyanBitmap = ColorHelpers.CreateBitmapFromPixelData(pixelWidth, pixelHeight, bgraMiddle3PixelData);
-                        _hueBlueBitmap = ColorHelpers.CreateBitmapFromPixelData(pixelWidth, pixelHeight, bgraMiddle4PixelData);
+                        _hueYellowBitmap = ColorPickerHelpers.CreateBitmapFromPixelData(bgraMiddle1PixelData, pixelWidth, pixelHeight);
+                        _hueGreenBitmap = ColorPickerHelpers.CreateBitmapFromPixelData(bgraMiddle2PixelData, pixelWidth, pixelHeight);
+                        _hueCyanBitmap = ColorPickerHelpers.CreateBitmapFromPixelData(bgraMiddle3PixelData, pixelWidth, pixelHeight);
+                        _hueBlueBitmap = ColorPickerHelpers.CreateBitmapFromPixelData(bgraMiddle4PixelData, pixelWidth, pixelHeight);
                         _huePurpleBitmap = maxBitmap;
                         break;
                 }
 
                 _shapeFromLastBitmapCreation = Shape;
                 _componentsFromLastBitmapCreation = Components;
-                _imageWidthFromLastBitmapCreation = minDimension;
-                _imageHeightFromLastBitmapCreation = minDimension;
+                _imageWidthFromLastBitmapCreation = pixelDimension;
+                _imageHeightFromLastBitmapCreation = pixelDimension;
                 _minHueFromLastBitmapCreation = MinHue;
                 _maxHueFromLastBitmapCreation = MaxHue;
                 _minSaturationFromLastBitmapCreation = MinSaturation;
@@ -1078,7 +1106,7 @@ namespace Avalonia.Controls.Primitives
             double x,
             double y,
             Hsv baseHsv,
-            double minDimension,
+            int minDimension,
             ColorSpectrumComponents components,
             double minHue,
             double maxHue,
@@ -1570,7 +1598,7 @@ namespace Avalonia.Controls.Primitives
                 displayedColor = Color;
             }
 
-            var lum = ColorHelpers.GetRelativeLuminance(displayedColor);
+            var lum = ColorHelper.GetRelativeLuminance(displayedColor);
 
             return lum <= 0.5;
         }

src/Avalonia.Controls.ColorPicker/Converters/AccentColorConverter.cs

@@ -0,0 +1,116 @@
+using System;
+using System.Globalization;
+using Avalonia.Data.Converters;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Primitives.Converters
+{
+    /// <summary>
+    /// Creates an accent color for a given base color value and step parameter.
+    /// This is a highly-specialized converter for the color picker.
+    /// </summary>
+    public class AccentColorConverter : IValueConverter
+    {
+        /// <summary>
+        /// The amount to change the Value component for each accent color step.
+        /// </summary>
+        public const double ValueDelta = 0.1;
+
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            int accentStep;
+            Color? rgbColor = null;
+            HsvColor? hsvColor = null;
+
+            if (value is Color valueColor)
+            {
+                rgbColor = valueColor;
+            }
+            else if (value is HslColor valueHslColor)
+            {
+                rgbColor = valueHslColor.ToRgb();
+            }
+            else if (value is HsvColor valueHsvColor)
+            {
+                hsvColor = valueHsvColor;
+            }
+            else if (value is SolidColorBrush valueBrush)
+            {
+                rgbColor = valueBrush.Color;
+            }
+            else
+            {
+                // Invalid color value provided
+                return AvaloniaProperty.UnsetValue;
+            }
+
+            // Get the value component delta
+            try
+            {
+                accentStep = int.Parse(parameter?.ToString() ?? "", CultureInfo.InvariantCulture);
+            }
+            catch
+            {
+                // Invalid parameter provided, unable to convert to integer
+                return AvaloniaProperty.UnsetValue;
+            }
+
+            if (hsvColor == null &&
+                rgbColor != null)
+            {
+                hsvColor = rgbColor.Value.ToHsv();
+            }
+
+            if (hsvColor != null)
+            {
+                return new SolidColorBrush(GetAccent(hsvColor.Value, accentStep).ToRgb());
+            }
+            else
+            {
+                return AvaloniaProperty.UnsetValue;
+            }
+        }
+
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            return AvaloniaProperty.UnsetValue;
+        }
+
+        /// <summary>
+        /// This does not account for perceptual differences and also does not match with
+        /// system accent color calculation.
+        /// </summary>
+        /// <remarks>
+        /// Use the HSV representation as it's more perceptual.
+        /// In most cases only the value is changed by a fixed percentage so the algorithm is reproducible.
+        /// </remarks>
+        /// <param name="hsvColor">The base color to calculate the accent from.</param>
+        /// <param name="accentStep">The number of accent color steps to move.</param>
+        /// <returns>The new accent color.</returns>
+        public static HsvColor GetAccent(HsvColor hsvColor, int accentStep)
+        {
+            if (accentStep != 0)
+            {
+                double colorValue = hsvColor.V;
+                colorValue += (accentStep * AccentColorConverter.ValueDelta);
+                colorValue = Math.Round(colorValue, 2);
+
+                return new HsvColor(hsvColor.A, hsvColor.H, hsvColor.S, colorValue);
+            }
+            else
+            {
+                return hsvColor;
+            }
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Converters/ColorToDisplayNameConverter.cs

@@ -0,0 +1,68 @@
+using System;
+using System.Globalization;
+using Avalonia.Controls.Primitives;
+using Avalonia.Data.Converters;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Converters
+{
+    /// <summary>
+    /// Gets the approximated display name for the color.
+    /// </summary>
+    public class ColorToDisplayNameConverter : IValueConverter
+    {
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            Color color;
+
+            if (value is Color valueColor)
+            {
+                color = valueColor;
+            }
+            else if (value is HslColor valueHslColor)
+            {
+                color = valueHslColor.ToRgb();
+            }
+            else if (value is HsvColor valueHsvColor)
+            {
+                color = valueHsvColor.ToRgb();
+            }
+            else if (value is SolidColorBrush valueBrush)
+            {
+                color = valueBrush.Color;
+            }
+            else
+            {
+                // Invalid color value provided
+                return AvaloniaProperty.UnsetValue;
+            }
+
+            // ColorHelper.ToDisplayName ignores the alpha component
+            // This means fully transparent colors will be named as a real color
+            // That undesirable behavior is specially overridden here
+            if (color.A == 0x00)
+            {
+                return AvaloniaProperty.UnsetValue;
+            }
+            else
+            {
+                return ColorHelper.ToDisplayName(color);
+            }
+        }
+
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            return AvaloniaProperty.UnsetValue;
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Converters/ColorToHexConverter.cs

@@ -0,0 +1,82 @@
+using System;
+using System.Globalization;
+using Avalonia.Data.Converters;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Converters
+{
+    /// <summary>
+    /// Converts a color to a hex string and vice versa.
+    /// </summary>
+    public class ColorToHexConverter : IValueConverter
+    {
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            Color color;
+            bool includeSymbol = parameter as bool? ?? false;
+
+            if (value is Color valueColor)
+            {
+                color = valueColor;
+            }
+            else if (value is HslColor valueHslColor)
+            {
+                color = valueHslColor.ToRgb();
+            }
+            else if (value is HsvColor valueHsvColor)
+            {
+                color = valueHsvColor.ToRgb();
+            }
+            else if (value is SolidColorBrush valueBrush)
+            {
+                color = valueBrush.Color;
+            }
+            else
+            {
+                // Invalid color value provided
+                return AvaloniaProperty.UnsetValue;
+            }
+
+            string hexColor = color.ToString();
+
+            if (includeSymbol == false)
+            {
+                // TODO: When .net standard 2.0 is dropped, replace the below line
+                //hexColor = hexColor.Replace("#", string.Empty, StringComparison.Ordinal);
+                hexColor = hexColor.Replace("#", string.Empty);
+            }
+
+            return hexColor;
+        }
+
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            string hexValue = value?.ToString() ?? string.Empty;
+
+            if (Color.TryParse(hexValue, out Color color))
+            {
+                return color;
+            }
+            else if (hexValue.StartsWith("#", StringComparison.Ordinal) == false &&
+                     Color.TryParse("#" + hexValue, out Color color2))
+            {
+                return color2;
+            }
+            else
+            {
+                // Invalid hex color value provided
+                return AvaloniaProperty.UnsetValue;
+            }
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Converters/ThirdComponentConverter.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace Avalonia.Controls.Primitives.Converters
+{
+    /// <summary>
+    /// Gets the third <see cref="ColorComponent"/> corresponding with a given
+    /// <see cref="ColorSpectrumComponents"/> that represents the other two components.
+    /// This is a highly-specialized converter for the color picker.
+    /// </summary>
+    public class ThirdComponentConverter : IValueConverter
+    {
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            if (value is ColorSpectrumComponents components)
+            {
+                // Note: Alpha is not relevant here
+                switch (components)
+                {
+                    case ColorSpectrumComponents.HueSaturation:
+                    case ColorSpectrumComponents.SaturationHue:
+                        return (ColorComponent)HsvComponent.Value;
+                    case ColorSpectrumComponents.HueValue:
+                    case ColorSpectrumComponents.ValueHue:
+                        return (ColorComponent)HsvComponent.Saturation;
+                    case ColorSpectrumComponents.SaturationValue:
+                    case ColorSpectrumComponents.ValueSaturation:
+                        return (ColorComponent)HsvComponent.Hue;
+                }
+            }
+
+            return AvaloniaProperty.UnsetValue;
+        }
+
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            return AvaloniaProperty.UnsetValue;
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Converters/ToBrushConverter.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Globalization;
+using Avalonia.Data.Converters;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Converters
+{
+    /// <summary>
+    /// Converts the given value into an <see cref="IBrush"/> when a conversion is possible.
+    /// </summary>
+    public class ToBrushConverter : IValueConverter
+    {
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            if (value is IBrush brush)
+            {
+                return brush;
+            }
+            else if (value is Color valueColor)
+            {
+                return new SolidColorBrush(valueColor);
+            }
+            else if (value is HslColor valueHslColor)
+            {
+                return new SolidColorBrush(valueHslColor.ToRgb());
+            }
+            else if (value is HsvColor valueHsvColor)
+            {
+                return new SolidColorBrush(valueHsvColor.ToRgb());
+            }
+
+            return AvaloniaProperty.UnsetValue;
+        }
+
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            return AvaloniaProperty.UnsetValue;
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Converters/ToColorConverter.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Globalization;
+using Avalonia.Data.Converters;
+using Avalonia.Media;
+using Avalonia.Utilities;
+
+namespace Avalonia.Controls.Converters
+{
+    /// <summary>
+    /// Converts the given value into a <see cref="Color"/> when a conversion is possible.
+    /// </summary>
+    public class ToColorConverter : IValueConverter
+    {
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            if (value is Color valueColor)
+            {
+                return valueColor;
+            }
+            else if (value is HslColor valueHslColor)
+            {
+                return valueHslColor.ToRgb();
+            }
+            else if (value is HsvColor valueHsvColor)
+            {
+                return valueHsvColor.ToRgb();
+            }
+            else if (value is SolidColorBrush valueBrush)
+            {
+                // A brush may have an opacity set along with alpha transparency
+                double alpha = valueBrush.Color.A * valueBrush.Opacity;
+
+                return new Color(
+                    (byte)MathUtilities.Clamp(alpha, 0x00, 0xFF),
+                    valueBrush.Color.R,
+                    valueBrush.Color.G,
+                    valueBrush.Color.B);
+            }
+
+            return AvaloniaProperty.UnsetValue;
+        }
+
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            return AvaloniaProperty.UnsetValue;
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Converters/ValueConverterGroup.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace Avalonia.Controls.Primitives.Converters
+{
+    /// <summary>
+    /// Converter to chain together multiple converters.
+    /// </summary>
+    public class ValueConverterGroup : List<IValueConverter>, IValueConverter
+    {
+        /// <inheritdoc/>
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            object? curValue;
+
+            curValue = value;
+            for (int i = 0; i < Count; i++)
+            {
+                curValue = this[i].Convert(curValue, targetType, parameter, culture);
+            }
+
+            return curValue;
+        }
+
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
+        {
+            object? curValue;
+
+            curValue = value;
+            for (int i = (Count - 1); i >= 0; i--)
+            {
+                curValue = this[i].ConvertBack(curValue, targetType, parameter, culture);
+            }
+
+            return curValue;
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Helpers/ColorHelper.cs

@@ -0,0 +1,142 @@
+using System;
+using System.Globalization;
+using System.Collections.Generic;
+using Avalonia.Media;
+using System.Text;
+
+namespace Avalonia.Controls.Primitives
+{
+    /// <summary>
+    /// Contains helpers useful when working with colors.
+    /// </summary>
+    public static class ColorHelper
+    {
+        private static readonly Dictionary<Color, string> cachedDisplayNames = new Dictionary<Color, string>();
+        private static readonly object cacheMutex = new object();
+
+        /// <summary>
+        /// Gets the relative (perceptual) luminance/brightness of the given color.
+        /// 1 is closer to white while 0 is closer to black.
+        /// </summary>
+        /// <param name="color">The color to calculate relative luminance for.</param>
+        /// <returns>The relative (perceptual) luminance/brightness of the given color.</returns>
+        public static double GetRelativeLuminance(Color color)
+        {
+            // The equation for relative luminance is given by
+            //
+            // L = 0.2126 * Rg + 0.7152 * Gg + 0.0722 * Bg
+            //
+            // where Xg = { X/3294 if X <= 10, (R/269 + 0.0513)^2.4 otherwise }
+            //
+            // If L is closer to 1, then the color is closer to white; if it is closer to 0,
+            // then the color is closer to black.  This is based on the fact that the human
+            // eye perceives green to be much brighter than red, which in turn is perceived to be
+            // brighter than blue.
+
+            double rg = color.R <= 10 ? color.R / 3294.0 : Math.Pow(color.R / 269.0 + 0.0513, 2.4);
+            double gg = color.G <= 10 ? color.G / 3294.0 : Math.Pow(color.G / 269.0 + 0.0513, 2.4);
+            double bg = color.B <= 10 ? color.B / 3294.0 : Math.Pow(color.B / 269.0 + 0.0513, 2.4);
+
+            return (0.2126 * rg + 0.7152 * gg + 0.0722 * bg);
+        }
+
+        /// <summary>
+        /// Determines if color display names are supported based on the current thread culture.
+        /// </summary>
+        /// <remarks>
+        /// Only English names are currently supported following known color names.
+        /// In the future known color names could be localized.
+        /// </remarks>
+        public static bool ToDisplayNameExists
+        {
+            get => CultureInfo.CurrentUICulture.Name.StartsWith("EN", StringComparison.OrdinalIgnoreCase);
+        }
+
+        /// <summary>
+        /// Determines an approximate display name for the given color.
+        /// </summary>
+        /// <param name="color">The color to get the display name for.</param>
+        /// <returns>The approximate color display name.</returns>
+        public static string ToDisplayName(Color color)
+        {
+            // Without rounding, there are 16,777,216 possible RGB colors (without alpha).
+            // This is too many to cache and search through for performance reasons.
+            // It is also needlessly large as there are only ~140 known/named colors.
+            // Therefore, rounding of the input color's component values is done to
+            // reduce the color space into something more useful.
+            double rounding = 5;
+            var roundedColor = new Color(
+                0xFF,
+                Convert.ToByte(Math.Round(color.R / rounding) * rounding),
+                Convert.ToByte(Math.Round(color.G / rounding) * rounding),
+                Convert.ToByte(Math.Round(color.B / rounding) * rounding));
+
+            // Attempt to use a previously cached display name
+            lock (cacheMutex)
+            {
+                if (cachedDisplayNames.TryGetValue(roundedColor, out var displayName))
+                {
+                    return displayName;
+                }
+            }
+
+            // Find the closest known color by measuring 3D Euclidean distance (ignore alpha)
+            var closestKnownColor = KnownColor.None;
+            var closestKnownColorDistance = double.PositiveInfinity;
+            var knownColors = (KnownColor[])Enum.GetValues(typeof(KnownColor));
+
+            for (int i = 1; i < knownColors.Length; i++) // Skip 'None'
+            {
+                // Transparent is skipped since alpha is ignored making it equivalent to White
+                if (knownColors[i] != KnownColor.Transparent)
+                {
+                    Color knownColor = KnownColors.ToColor(knownColors[i]);
+
+                    double distance = Math.Sqrt(
+                        Math.Pow((double)(roundedColor.R - knownColor.R), 2.0) +
+                        Math.Pow((double)(roundedColor.G - knownColor.G), 2.0) +
+                        Math.Pow((double)(roundedColor.B - knownColor.B), 2.0));
+
+                    if (distance < closestKnownColorDistance)
+                    {
+                        closestKnownColor = knownColors[i];
+                        closestKnownColorDistance = distance;
+                    }
+                }
+            }
+
+            // Return the closest known color as the display name
+            // Cache results for next time as well
+            if (closestKnownColor != KnownColor.None)
+            {
+                StringBuilder sb = new StringBuilder(); 
+                string name = closestKnownColor.ToString();
+
+                // Add spaces converting PascalCase to human-readable names
+                for (int i = 0; i < name.Length; i++)
+                {
+                    if (i != 0 &&
+                        char.IsUpper(name[i]))
+                    {
+                        sb.Append(' ');
+                    }
+
+                    sb.Append(name[i]);
+                }
+
+                string displayName = sb.ToString();
+
+                lock (cacheMutex)
+                {
+                    cachedDisplayNames.Add(roundedColor, displayName);
+                }
+
+                return displayName;
+            }
+            else
+            {
+                return string.Empty;
+            }
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/Helpers/ColorPickerHelpers.cs

@@ -0,0 +1,629 @@
+// This source file is adapted from the WinUI project.
+// (https://github.com/microsoft/microsoft-ui-xaml)
+//
+// Licensed to The Avalonia Project under the MIT License.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Threading.Tasks;
+using Avalonia.Layout;
+using Avalonia.Media;
+using Avalonia.Media.Imaging;
+using Avalonia.Platform;
+using Avalonia.Utilities;
+
+namespace Avalonia.Controls.Primitives
+{
+    /// <summary>
+    /// Contains internal, special-purpose helpers used with the color picker.
+    /// </summary>
+    internal static class ColorPickerHelpers
+    {
+        /// <summary>
+        /// Generates a new bitmap of the specified size by changing a specific color component.
+        /// This will produce a gradient representing a sweep of all possible values of the color component.
+        /// </summary>
+        /// <param name="width">The pixel width (X, horizontal) of the resulting bitmap.</param>
+        /// <param name="height">The pixel height (Y, vertical) of the resulting bitmap.</param>
+        /// <param name="orientation">The orientation of the resulting bitmap (gradient direction).</param>
+        /// <param name="colorModel">The color model being used: RGBA or HSVA.</param>
+        /// <param name="component">The specific color component to sweep.</param>
+        /// <param name="baseHsvColor">The base HSV color used for components not being changed.</param>
+        /// <param name="isAlphaMaxForced">Fix the alpha component value to maximum during calculation.
+        /// This will remove any alpha/transparency from the other component backgrounds.</param>
+        /// <param name="isSaturationValueMaxForced">Fix the saturation and value components to maximum
+        /// during calculation with the HSVA color model.
+        /// This will ensure colors are always discernible regardless of saturation/value.</param>
+        /// <returns>A new bitmap representing a gradient of color component values.</returns>
+        public static async Task<byte[]> CreateComponentBitmapAsync(
+            int width,
+            int height,
+            Orientation orientation,
+            ColorModel colorModel,
+            ColorComponent component,
+            HsvColor baseHsvColor,
+            bool isAlphaMaxForced,
+            bool isSaturationValueMaxForced)
+        {
+            if (width == 0 || height == 0)
+            {
+                return new byte[0];
+            }
+
+            var bitmap = await Task.Run<byte[]>(() =>
+            {
+                int pixelDataIndex = 0;
+                double componentStep;
+                byte[] bgraPixelData;
+                Color baseRgbColor = Colors.White;
+                Color rgbColor;
+                int bgraPixelDataHeight;
+                int bgraPixelDataWidth;
+
+                // Allocate the buffer
+                // BGRA formatted color components 1 byte each (4 bytes in a pixel)
+                bgraPixelData       = new byte[width * height * 4];
+                bgraPixelDataHeight = height * 4;
+                bgraPixelDataWidth  = width * 4;
+
+                // Maximize alpha component value
+                if (isAlphaMaxForced &&
+                    component != ColorComponent.Alpha)
+                {
+                    baseHsvColor = new HsvColor(1.0, baseHsvColor.H, baseHsvColor.S, baseHsvColor.V);
+                }
+
+                // Convert HSV to RGB once
+                if (colorModel == ColorModel.Rgba)
+                {
+                    baseRgbColor = baseHsvColor.ToRgb();
+                }
+
+                // Maximize Saturation and Value components when in HSVA mode
+                if (isSaturationValueMaxForced &&
+                    colorModel == ColorModel.Hsva &&
+                    component != ColorComponent.Alpha)
+                {
+                    switch (component)
+                    {
+                        case ColorComponent.Component1:
+                            baseHsvColor = new HsvColor(baseHsvColor.A, baseHsvColor.H, 1.0, 1.0);
+                            break;
+                        case ColorComponent.Component2:
+                            baseHsvColor = new HsvColor(baseHsvColor.A, baseHsvColor.H, baseHsvColor.S, 1.0);
+                            break;
+                        case ColorComponent.Component3:
+                            baseHsvColor = new HsvColor(baseHsvColor.A, baseHsvColor.H, 1.0, baseHsvColor.V);
+                            break;
+                    }
+                }
+
+                // Create the color component gradient
+                if (orientation == Orientation.Horizontal)
+                {
+                    // Determine the numerical increment of the color steps within the component
+                    if (colorModel == ColorModel.Hsva)
+                    {
+                        if (component == ColorComponent.Component1)
+                        {
+                            componentStep = 360.0 / width;
+                        }
+                        else
+                        {
+                            componentStep = 1.0 / width;
+                        }
+                    }
+                    else
+                    {
+                        componentStep = 255.0 / width;
+                    }
+
+                    for (int y = 0; y < height; y++)
+                    {
+                        for (int x = 0; x < width; x++)
+                        {
+                            if (y == 0)
+                            {
+                                rgbColor = GetColor(x * componentStep);
+
+                                // Get a new color
+                                bgraPixelData[pixelDataIndex + 0] = Convert.ToByte(rgbColor.B * rgbColor.A / 255);
+                                bgraPixelData[pixelDataIndex + 1] = Convert.ToByte(rgbColor.G * rgbColor.A / 255);
+                                bgraPixelData[pixelDataIndex + 2] = Convert.ToByte(rgbColor.R * rgbColor.A / 255);
+                                bgraPixelData[pixelDataIndex + 3] = rgbColor.A;
+                            }
+                            else
+                            {
+                                // Use the color in the row above
+                                // Remember the pixel data is 1 dimensional instead of 2
+                                bgraPixelData[pixelDataIndex + 0] = bgraPixelData[pixelDataIndex + 0 - bgraPixelDataWidth];
+                                bgraPixelData[pixelDataIndex + 1] = bgraPixelData[pixelDataIndex + 1 - bgraPixelDataWidth];
+                                bgraPixelData[pixelDataIndex + 2] = bgraPixelData[pixelDataIndex + 2 - bgraPixelDataWidth];
+                                bgraPixelData[pixelDataIndex + 3] = bgraPixelData[pixelDataIndex + 3 - bgraPixelDataWidth];
+                            }
+
+                            pixelDataIndex += 4;
+                        }
+                    }
+                }
+                else
+                {
+                    // Determine the numerical increment of the color steps within the component
+                    if (colorModel == ColorModel.Hsva)
+                    {
+                        if (component == ColorComponent.Component1)
+                        {
+                            componentStep = 360.0 / height;
+                        }
+                        else
+                        {
+                            componentStep = 1.0 / height;
+                        }
+                    }
+                    else
+                    {
+                        componentStep = 255.0 / height;
+                    }
+
+                    for (int y = 0; y < height; y++)
+                    {
+                        for (int x = 0; x < width; x++)
+                        {
+                            if (x == 0)
+                            {
+                                // The lowest component value should be at the 'bottom' of the bitmap
+                                rgbColor = GetColor((height - 1 - y) * componentStep);
+
+                                // Get a new color
+                                bgraPixelData[pixelDataIndex + 0] = Convert.ToByte(rgbColor.B * rgbColor.A / 255);
+                                bgraPixelData[pixelDataIndex + 1] = Convert.ToByte(rgbColor.G * rgbColor.A / 255);
+                                bgraPixelData[pixelDataIndex + 2] = Convert.ToByte(rgbColor.R * rgbColor.A / 255);
+                                bgraPixelData[pixelDataIndex + 3] = rgbColor.A;
+                            }
+                            else
+                            {
+                                // Use the color in the column to the left
+                                // Remember the pixel data is 1 dimensional instead of 2
+                                bgraPixelData[pixelDataIndex + 0] = bgraPixelData[pixelDataIndex - 4];
+                                bgraPixelData[pixelDataIndex + 1] = bgraPixelData[pixelDataIndex - 3];
+                                bgraPixelData[pixelDataIndex + 2] = bgraPixelData[pixelDataIndex - 2];
+                                bgraPixelData[pixelDataIndex + 3] = bgraPixelData[pixelDataIndex - 1];
+                            }
+
+                            pixelDataIndex += 4;
+                        }
+                    }
+                }
+
+                Color GetColor(double componentValue)
+                {
+                    Color newRgbColor = Colors.White;
+
+                    switch (component)
+                    {
+                        case ColorComponent.Component1:
+                            {
+                                if (colorModel == ColorModel.Hsva)
+                                {
+                                    // Sweep hue
+                                    newRgbColor = HsvColor.ToRgb(
+                                        MathUtilities.Clamp(componentValue, 0.0, 360.0),
+                                        baseHsvColor.S,
+                                        baseHsvColor.V,
+                                        baseHsvColor.A);
+                                }
+                                else
+                                {
+                                    // Sweep red
+                                    newRgbColor = new Color(
+                                        baseRgbColor.A,
+                                        Convert.ToByte(MathUtilities.Clamp(componentValue, 0.0, 255.0)),
+                                        baseRgbColor.G,
+                                        baseRgbColor.B);
+                                }
+
+                                break;
+                            }
+                        case ColorComponent.Component2:
+                            {
+                                if (colorModel == ColorModel.Hsva)
+                                {
+                                    // Sweep saturation
+                                    newRgbColor = HsvColor.ToRgb(
+                                        baseHsvColor.H,
+                                        MathUtilities.Clamp(componentValue, 0.0, 1.0),
+                                        baseHsvColor.V,
+                                        baseHsvColor.A);
+                                }
+                                else
+                                {
+                                    // Sweep green
+                                    newRgbColor = new Color(
+                                        baseRgbColor.A,
+                                        baseRgbColor.R,
+                                        Convert.ToByte(MathUtilities.Clamp(componentValue, 0.0, 255.0)),
+                                        baseRgbColor.B);
+                                }
+
+                                break;
+                            }
+                        case ColorComponent.Component3:
+                            {
+                                if (colorModel == ColorModel.Hsva)
+                                {
+                                    // Sweep value
+                                    newRgbColor = HsvColor.ToRgb(
+                                        baseHsvColor.H,
+                                        baseHsvColor.S,
+                                        MathUtilities.Clamp(componentValue, 0.0, 1.0),
+                                        baseHsvColor.A);
+                                }
+                                else
+                                {
+                                    // Sweep blue
+                                    newRgbColor = new Color(
+                                        baseRgbColor.A,
+                                        baseRgbColor.R,
+                                        baseRgbColor.G,
+                                        Convert.ToByte(MathUtilities.Clamp(componentValue, 0.0, 255.0)));
+                                }
+
+                                break;
+                            }
+                        case ColorComponent.Alpha:
+                            {
+                                if (colorModel == ColorModel.Hsva)
+                                {
+                                    // Sweep alpha
+                                    newRgbColor = HsvColor.ToRgb(
+                                        baseHsvColor.H,
+                                        baseHsvColor.S,
+                                        baseHsvColor.V,
+                                        MathUtilities.Clamp(componentValue, 0.0, 1.0));
+                                }
+                                else
+                                {
+                                    // Sweep alpha
+                                    newRgbColor = new Color(
+                                        Convert.ToByte(MathUtilities.Clamp(componentValue, 0.0, 255.0)),
+                                        baseRgbColor.R,
+                                        baseRgbColor.G,
+                                        baseRgbColor.B);
+                                }
+
+                                break;
+                            }
+                    }
+
+                    return newRgbColor;
+                }
+
+                return bgraPixelData;
+            });
+
+            return bitmap;
+        }
+
+        public static Hsv IncrementColorComponent(
+            Hsv originalHsv,
+            HsvComponent component,
+            IncrementDirection direction,
+            IncrementAmount amount,
+            bool shouldWrap,
+            double minBound,
+            double maxBound)
+        {
+            Hsv newHsv = originalHsv;
+
+            if (amount == IncrementAmount.Small || !ColorHelper.ToDisplayNameExists)
+            {
+                // In order to avoid working with small values that can incur rounding issues,
+                // we'll multiple saturation and value by 100 to put them in the range of 0-100 instead of 0-1.
+                newHsv.S *= 100;
+                newHsv.V *= 100;
+
+                // Note: *valueToIncrement replaced with ref local variable for C#, must be initialized
+                ref double valueToIncrement = ref newHsv.H;
+                double incrementAmount = 0.0;
+
+                // If we're adding a small increment, then we'll just add or subtract 1.
+                // If we're adding a large increment, then we want to snap to the next
+                // or previous major value - for hue, this is every increment of 30;
+                // for saturation and value, this is every increment of 10.
+                switch (component)
+                {
+                    case HsvComponent.Hue:
+                        valueToIncrement = ref newHsv.H;
+                        incrementAmount = amount == IncrementAmount.Small ? 1 : 30;
+                        break;
+
+                    case HsvComponent.Saturation:
+                        valueToIncrement = ref newHsv.S;
+                        incrementAmount = amount == IncrementAmount.Small ? 1 : 10;
+                        break;
+
+                    case HsvComponent.Value:
+                        valueToIncrement = ref newHsv.V;
+                        incrementAmount = amount == IncrementAmount.Small ? 1 : 10;
+                        break;
+
+                    default:
+                        throw new InvalidOperationException("Invalid HsvComponent.");
+                }
+
+                double previousValue = valueToIncrement;
+
+                valueToIncrement += (direction == IncrementDirection.Lower ? -incrementAmount : incrementAmount);
+
+                // If the value has reached outside the bounds, we were previous at the boundary, and we should wrap,
+                // then we'll place the selection on the other side of the spectrum.
+                // Otherwise, we'll place it on the boundary that was exceeded.
+                if (valueToIncrement < minBound)
+                {
+                    valueToIncrement = (shouldWrap && previousValue == minBound) ? maxBound : minBound;
+                }
+
+                if (valueToIncrement > maxBound)
+                {
+                    valueToIncrement = (shouldWrap && previousValue == maxBound) ? minBound : maxBound;
+                }
+
+                // We multiplied saturation and value by 100 previously, so now we want to put them back in the 0-1 range.
+                newHsv.S /= 100;
+                newHsv.V /= 100;
+            }
+            else
+            {
+                // While working with named colors, we're going to need to be working in actual HSV units,
+                // so we'll divide the min bound and max bound by 100 in the case of saturation or value,
+                // since we'll have received units between 0-100 and we need them within 0-1.
+                if (component == HsvComponent.Saturation ||
+                    component == HsvComponent.Value)
+                {
+                    minBound /= 100;
+                    maxBound /= 100;
+                }
+
+                newHsv = FindNextNamedColor(originalHsv, component, direction, shouldWrap, minBound, maxBound);
+            }
+
+            return newHsv;
+        }
+
+        public static Hsv FindNextNamedColor(
+            Hsv originalHsv,
+            HsvComponent component,
+            IncrementDirection direction,
+            bool shouldWrap,
+            double minBound,
+            double maxBound)
+        {
+            // There's no easy way to directly get the next named color, so what we'll do
+            // is just iterate in the direction that we want to find it until we find a color
+            // in that direction that has a color name different than our current color name.
+            // Once we find a new color name, then we'll iterate across that color name until
+            // we find its bounds on the other side, and then select the color that is exactly
+            // in the middle of that color's bounds.
+            Hsv newHsv = originalHsv;
+            
+            string originalColorName = ColorHelper.ToDisplayName(originalHsv.ToRgb().ToColor());
+            string newColorName = originalColorName;
+
+            // Note: *newValue replaced with ref local variable for C#, must be initialized
+            double originalValue = 0.0;
+            ref double newValue = ref newHsv.H;
+            double incrementAmount = 0.0;
+
+            switch (component)
+            {
+                case HsvComponent.Hue:
+                    originalValue = originalHsv.H;
+                    newValue = ref newHsv.H;
+                    incrementAmount = 1;
+                    break;
+
+                case HsvComponent.Saturation:
+                    originalValue = originalHsv.S;
+                    newValue = ref newHsv.S;
+                    incrementAmount = 0.01;
+                    break;
+
+                case HsvComponent.Value:
+                    originalValue = originalHsv.V;
+                    newValue = ref newHsv.V;
+                    incrementAmount = 0.01;
+                    break;
+
+                default:
+                    throw new InvalidOperationException("Invalid HsvComponent.");
+            }
+
+            bool shouldFindMidPoint = true;
+
+            while (newColorName == originalColorName)
+            {
+                double previousValue = newValue;
+                newValue += (direction == IncrementDirection.Lower ? -1 : 1) * incrementAmount;
+
+                bool justWrapped = false;
+
+                // If we've hit a boundary, then either we should wrap or we shouldn't.
+                // If we should, then we'll perform that wrapping if we were previously up against
+                // the boundary that we've now hit.  Otherwise, we'll stop at that boundary.
+                if (newValue > maxBound)
+                {
+                    if (shouldWrap)
+                    {
+                        newValue = minBound;
+                        justWrapped = true;
+                    }
+                    else
+                    {
+                        newValue = maxBound;
+                        shouldFindMidPoint = false;
+                        newColorName = ColorHelper.ToDisplayName(newHsv.ToRgb().ToColor());
+                        break;
+                    }
+                }
+                else if (newValue < minBound)
+                {
+                    if (shouldWrap)
+                    {
+                        newValue = maxBound;
+                        justWrapped = true;
+                    }
+                    else
+                    {
+                        newValue = minBound;
+                        shouldFindMidPoint = false;
+                        newColorName = ColorHelper.ToDisplayName(newHsv.ToRgb().ToColor());
+                        break;
+                    }
+                }
+
+                if (!justWrapped &&
+                    previousValue != originalValue &&
+                    Math.Sign(newValue - originalValue) != Math.Sign(previousValue - originalValue))
+                {
+                    // If we've wrapped all the way back to the start and have failed to find a new color name,
+                    // then we'll just quit - there isn't a new color name that we're going to find.
+                    shouldFindMidPoint = false;
+                    break;
+                }
+
+                newColorName = ColorHelper.ToDisplayName(newHsv.ToRgb().ToColor());
+            }
+
+            if (shouldFindMidPoint)
+            {
+                Hsv startHsv = newHsv;
+                Hsv currentHsv = startHsv;
+                double startEndOffset = 0;
+                string currentColorName = newColorName;
+
+                // Note: *startValue/*currentValue replaced with ref local variables for C#, must be initialized
+                ref double startValue = ref startHsv.H;
+                ref double currentValue = ref currentHsv.H;
+                double wrapIncrement = 0;
+
+                switch (component)
+                {
+                    case HsvComponent.Hue:
+                        startValue = ref startHsv.H;
+                        currentValue = ref currentHsv.H;
+                        wrapIncrement = 360.0;
+                        break;
+
+                    case HsvComponent.Saturation:
+                        startValue = ref startHsv.S;
+                        currentValue = ref currentHsv.S;
+                        wrapIncrement = 1.0;
+                        break;
+
+                    case HsvComponent.Value:
+                        startValue = ref startHsv.V;
+                        currentValue = ref currentHsv.V;
+                        wrapIncrement = 1.0;
+                        break;
+
+                    default:
+                        throw new InvalidOperationException("Invalid HsvComponent.");
+                }
+
+                while (newColorName == currentColorName)
+                {
+                    currentValue += (direction == IncrementDirection.Lower ? -1 : 1) * incrementAmount;
+
+                    // If we've hit a boundary, then either we should wrap or we shouldn't.
+                    // If we should, then we'll perform that wrapping if we were previously up against
+                    // the boundary that we've now hit.  Otherwise, we'll stop at that boundary.
+                    if (currentValue > maxBound)
+                    {
+                        if (shouldWrap)
+                        {
+                            currentValue = minBound;
+                            startEndOffset = maxBound - minBound;
+                        }
+                        else
+                        {
+                            currentValue = maxBound;
+                            break;
+                        }
+                    }
+                    else if (currentValue < minBound)
+                    {
+                        if (shouldWrap)
+                        {
+                            currentValue = maxBound;
+                            startEndOffset = minBound - maxBound;
+                        }
+                        else
+                        {
+                            currentValue = minBound;
+                            break;
+                        }
+                    }
+
+                    currentColorName = ColorHelper.ToDisplayName(currentHsv.ToRgb().ToColor());
+                }
+
+                newValue = (startValue + currentValue + startEndOffset) / 2;
+
+                // Dividing by 2 may have gotten us halfway through a single step, so we'll
+                // remove that half-step if it exists.
+                double leftoverValue = Math.Abs(newValue);
+
+                while (leftoverValue > incrementAmount)
+                {
+                    leftoverValue -= incrementAmount;
+                }
+
+                newValue -= leftoverValue;
+
+                while (newValue < minBound)
+                {
+                    newValue += wrapIncrement;
+                }
+
+                while (newValue > maxBound)
+                {
+                    newValue -= wrapIncrement;
+                }
+            }
+
+            return newHsv;
+        }
+
+        /// <summary>
+        /// Converts the given raw BGRA pre-multiplied alpha pixel data into a bitmap.
+        /// </summary>
+        /// <param name="bgraPixelData">The bitmap (in raw BGRA pre-multiplied alpha pixels).</param>
+        /// <param name="pixelWidth">The pixel width of the bitmap.</param>
+        /// <param name="pixelHeight">The pixel height of the bitmap.</param>
+        /// <returns>A new <see cref="WriteableBitmap"/>.</returns>
+        public static WriteableBitmap CreateBitmapFromPixelData(
+            IList<byte> bgraPixelData,
+            int pixelWidth,
+            int pixelHeight)
+        {
+            // Standard may need to change on some devices
+            Vector dpi = new Vector(96, 96);
+
+            var bitmap = new WriteableBitmap(
+                new PixelSize(pixelWidth, pixelHeight),
+                dpi,
+                PixelFormat.Bgra8888,
+                AlphaFormat.Premul);
+
+            // Warning: This is highly questionable
+            using (var frameBuffer = bitmap.Lock())
+            {
+                Marshal.Copy(bgraPixelData.ToArray(), 0, frameBuffer.Address, bgraPixelData.Count);
+            }
+
+            return bitmap;
+        }
+    }
+}

src/Avalonia.Controls.ColorPicker/HsvComponent.cs

@@ -12,13 +12,21 @@ namespace Avalonia.Controls
     /// </summary>
     public enum HsvComponent
     {
+        /// <summary>
+        /// The Alpha component.
+        /// </summary>
+        /// <remarks>
+        /// Also see: <see cref="HsvColor.A"/>
+        /// </remarks>
+        Alpha = 0,
+
         /// <summary>
         /// The Hue component.
         /// </summary>
         /// <remarks>
         /// Also see: <see cref="HsvColor.H"/>
         /// </remarks>
-        Hue,
+        Hue = 1,
 
         /// <summary>
         /// The Saturation component.
@@ -26,7 +34,7 @@ namespace Avalonia.Controls
         /// <remarks>
         /// Also see: <see cref="HsvColor.S"/>
         /// </remarks>
-        Saturation,
+        Saturation = 2,
 
         /// <summary>
         /// The Value component.
@@ -34,14 +42,6 @@ namespace Avalonia.Controls
         /// <remarks>
         /// Also see: <see cref="HsvColor.V"/>
         /// </remarks>
-        Value,
-
-        /// <summary>
-        /// The Alpha component.
-        /// </summary>
-        /// <remarks>
-        /// Also see: <see cref="HsvColor.A"/>
-        /// </remarks>
-        Alpha
+        Value = 3
     };
 }

src/Avalonia.Controls.ColorPicker/RgbComponent.cs

@@ -0,0 +1,42 @@
+using Avalonia.Media;
+
+namespace Avalonia.Controls
+{
+    /// <summary>
+    /// Defines a specific component in the RGB color model.
+    /// </summary>
+    public enum RgbComponent
+    {
+        /// <summary>
+        /// The Alpha component.
+        /// </summary>
+        /// <remarks>
+        /// Also see: <see cref="Color.A"/>
+        /// </remarks>
+        Alpha = 0,
+
+        /// <summary>
+        /// The Red component.
+        /// </summary>
+        /// <remarks>
+        /// Also see: <see cref="Color.R"/>
+        /// </remarks>
+        Red = 1,
+
+        /// <summary>
+        /// The Green component.
+        /// </summary>
+        /// <remarks>
+        /// Also see: <see cref="Color.G"/>
+        /// </remarks>
+        Green = 2,
+
+        /// <summary>
+        /// The Blue component.
+        /// </summary>
+        /// <remarks>
+        /// Also see: <see cref="Color.B"/>
+        /// </remarks>
+        Blue = 3
+    };
+}

src/Avalonia.Controls.ColorPicker/Themes/Default/ColorPreviewer.xaml

@@ -0,0 +1,86 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        xmlns:pc="using:Avalonia.Controls.Primitives.Converters"
+        x:CompileBindings="True">
+
+  <Styles.Resources>
+    <pc:AccentColorConverter x:Key="AccentColor" />
+    <converters:ToBrushConverter x:Key="ToBrush" />
+    <converters:CornerRadiusFilterConverter x:Key="RightCornerRadiusFilterConverter" Filter="TopRight, BottomRight"/>
+    <converters:CornerRadiusFilterConverter x:Key="LeftCornerRadiusFilterConverter" Filter="TopLeft, BottomLeft"/>
+  </Styles.Resources>
+
+  <Style Selector="ColorPreviewer">
+    <Setter Property="Height" Value="70" />
+    <Setter Property="CornerRadius" Value="0" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Grid ColumnDefinitions="Auto,*,Auto">
+          <!-- Left accent colors -->
+          <Grid Grid.Column="0"
+                Height="40"
+                Width="80"
+                ColumnDefinitions="*,*"
+                Margin="0,0,-10,0"
+                VerticalAlignment="Center"
+                IsVisible="{TemplateBinding ShowAccentColors}">
+            <Border Grid.Column="0"
+                    Grid.ColumnSpan="2"
+                    HorizontalAlignment="Stretch"
+                    VerticalAlignment="Stretch"
+                    Background="{StaticResource CheckeredBackgroundBrush}" />
+            <Border x:Name="AccentDec2Border"
+                    Grid.Column="0"
+                    CornerRadius="{TemplateBinding CornerRadius, Converter={StaticResource LeftCornerRadiusFilterConverter}}"
+                    Tag="-2"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='-2'}" />
+            <Border x:Name="AccentDec1Border"
+                    Grid.Column="1"
+                    Tag="-1"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='-1'}" />
+          </Grid>
+          <!-- Right accent colors -->
+          <Grid Grid.Column="2"
+                Height="40"
+                Width="80"
+                ColumnDefinitions="*,*"
+                Margin="-10,0,0,0"
+                VerticalAlignment="Center"
+                IsVisible="{TemplateBinding ShowAccentColors}">
+            <Border Grid.Column="0"
+                    Grid.ColumnSpan="2"
+                    HorizontalAlignment="Stretch"
+                    VerticalAlignment="Stretch"
+                    Background="{StaticResource CheckeredBackgroundBrush}" />
+            <Border x:Name="AccentInc1Border"
+                    Grid.Column="0"
+                    Tag="1"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='1'}" />
+            <Border x:Name="AccentInc2Border"
+                    Grid.Column="1"
+                    CornerRadius="{TemplateBinding CornerRadius, Converter={StaticResource RightCornerRadiusFilterConverter}}"
+                    Tag="2"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='2'}" />
+          </Grid>
+          <!-- Must be last for drop shadow Z-index -->
+          <Border Grid.Column="1"
+                  BoxShadow="0 0 10 2 #BF000000"
+                  CornerRadius="{TemplateBinding CornerRadius}"
+                  Margin="10">
+            <Panel>
+              <Border Background="{StaticResource CheckeredBackgroundBrush}"
+                      CornerRadius="{TemplateBinding CornerRadius}" />
+              <Border x:Name="PreviewBorder"
+                      CornerRadius="{TemplateBinding CornerRadius}"
+                      Background="{TemplateBinding HsvColor, Converter={StaticResource ToBrush}}"
+                      HorizontalAlignment="Stretch"
+                      VerticalAlignment="Stretch" />
+            </Panel>
+          </Border>
+        </Grid>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+</Styles>

src/Avalonia.Controls.ColorPicker/Themes/Default/ColorSlider.xaml

@@ -0,0 +1,194 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        x:CompileBindings="True">
+
+  <Styles.Resources>
+    <converters:CornerRadiusToDoubleConverter x:Key="TopLeftCornerRadius" Corner="TopLeft" />
+    <converters:CornerRadiusToDoubleConverter x:Key="BottomRightCornerRadius" Corner="BottomRight" />
+  </Styles.Resources>
+
+  <Style Selector="Thumb.ColorSliderThumbStyle">
+    <Setter Property="BorderThickness" Value="0" />
+    <Setter Property="Template">
+      <Setter.Value>
+        <ControlTemplate>
+          <Border Background="{TemplateBinding Background}"
+                  BorderBrush="{TemplateBinding BorderBrush}"
+                  BorderThickness="{TemplateBinding BorderThickness}"
+                  CornerRadius="10" />
+        </ControlTemplate>
+      </Setter.Value>
+    </Setter>
+  </Style>
+
+  <Style Selector="ColorSlider:horizontal">
+    <Setter Property="BorderThickness" Value="0" />
+    <Setter Property="CornerRadius" Value="10" />
+    <Setter Property="Height" Value="20" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border BorderThickness="{TemplateBinding BorderThickness}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                CornerRadius="{TemplateBinding CornerRadius}">
+          <Grid Margin="{TemplateBinding Padding}">
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{StaticResource CheckeredBackgroundBrush}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{TemplateBinding Background}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Track Name="PART_Track"
+                   HorizontalAlignment="Stretch"
+                   VerticalAlignment="Stretch"
+                   Minimum="{TemplateBinding Minimum}"
+                   Maximum="{TemplateBinding Maximum}"
+                   Value="{TemplateBinding Value, Mode=TwoWay}"
+                   IsDirectionReversed="{TemplateBinding IsDirectionReversed}"
+                   Orientation="Horizontal">
+              <Track.DecreaseButton>
+                <RepeatButton Name="PART_DecreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.DecreaseButton>
+              <Track.IncreaseButton>
+                <RepeatButton Name="PART_IncreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.IncreaseButton>
+              <Thumb Classes="ColorSliderThumbStyle"
+                     Name="ColorSliderThumb"
+                     Margin="0"
+                     Padding="0"
+                     DataContext="{TemplateBinding Value}"
+                     Height="{TemplateBinding Height}"
+                     Width="{TemplateBinding Height}" />
+            </Track>
+          </Grid>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <Style Selector="ColorSlider:vertical">
+    <Setter Property="BorderThickness" Value="0" />
+    <Setter Property="CornerRadius" Value="10" />
+    <Setter Property="Width" Value="20" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border BorderThickness="{TemplateBinding BorderThickness}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                CornerRadius="{TemplateBinding CornerRadius}">
+          <Grid Margin="{TemplateBinding Padding}">
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{StaticResource CheckeredBackgroundBrush}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{TemplateBinding Background}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Track Name="PART_Track"
+                   HorizontalAlignment="Stretch"
+                   VerticalAlignment="Stretch"
+                   Minimum="{TemplateBinding Minimum}"
+                   Maximum="{TemplateBinding Maximum}"
+                   Value="{TemplateBinding Value, Mode=TwoWay}"
+                   IsDirectionReversed="{TemplateBinding IsDirectionReversed}"
+                   Orientation="Vertical">
+              <Track.DecreaseButton>
+                <RepeatButton Name="PART_DecreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.DecreaseButton>
+              <Track.IncreaseButton>
+                <RepeatButton Name="PART_IncreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.IncreaseButton>
+              <Thumb Classes="ColorSliderThumbStyle"
+                     Name="ColorSliderThumb"
+                     Margin="0"
+                     Padding="0"
+                     DataContext="{TemplateBinding Value}"
+                     Height="{TemplateBinding Width}"
+                     Width="{TemplateBinding Width}" />
+            </Track>
+          </Grid>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <!-- Normal State -->
+  <Style Selector="ColorSlider /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Background" Value="Transparent" />
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeForegroundBrush}" />
+    <Setter Property="BorderThickness" Value="3" />
+  </Style>
+
+  <!-- Selector/Thumb Color -->
+  <Style Selector="ColorSlider:pointerover /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Opacity" Value="0.75" />
+  </Style>
+  <Style Selector="ColorSlider:pointerover:dark-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Opacity" Value="0.7" />
+  </Style>
+  <Style Selector="ColorSlider:pointerover:light-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Opacity" Value="0.8" />
+  </Style>
+
+  <Style Selector="ColorSlider:dark-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="BorderBrush" Value="Black" />
+  </Style>
+  <Style Selector="ColorSlider:light-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="BorderBrush" Value="White" />
+  </Style>
+
+</Styles>

src/Avalonia.Controls.ColorPicker/Themes/Default.xaml → src/Avalonia.Controls.ColorPicker/Themes/Default/ColorSpectrum.xaml

@@ -1,7 +1,7 @@
-<Styles xmlns="https://github.com/avaloniaui"
+<Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        x:CompileBindings="True"
-        xmlns:converters="using:Avalonia.Controls.Converters">
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        x:CompileBindings="True">
 
   <Styles.Resources>
     <converters:EnumValueEqualsConverter x:Key="EnumValueEquals" />
@@ -48,7 +48,10 @@
                       Background="Transparent"
                       HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch">
-                <Panel x:Name="PART_SelectionEllipsePanel">
+                <!-- Note: ToolTip.VerticalOffset is for touch devices to keep the tip above fingers -->
+                <Panel x:Name="PART_SelectionEllipsePanel"
+                       ToolTip.VerticalOffset="-10"
+                       ToolTip.Placement="Top">
                   <Ellipse x:Name="FocusEllipse"
                            Margin="-2"
                            StrokeThickness="2"
@@ -59,13 +62,10 @@
                            StrokeThickness="2"
                            IsHitTestVisible="False"
                            HorizontalAlignment="Stretch"
-                           VerticalAlignment="Stretch"
-                           ToolTip.VerticalOffset="-20"
-                           ToolTip.Placement="Top">
-                    <ToolTip.Tip>
-                      <ToolTip x:Name="PART_ColorNameToolTip" />
-                    </ToolTip.Tip>
-                  </Ellipse>
+                           VerticalAlignment="Stretch" />
+                  <ToolTip.Tip>
+                    <!-- Set in code-behind -->
+                  </ToolTip.Tip>
                 </Panel>
               </Canvas>
               <Rectangle x:Name="BorderRectangle"

src/Avalonia.Controls.ColorPicker/Themes/Default/Default.xaml

@@ -0,0 +1,28 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+
+  <Styles.Resources>
+    <VisualBrush x:Key="CheckeredBackgroundBrush"
+                 TileMode="Tile"
+                 Stretch="Uniform"
+                 DestinationRect="0,0,8,8">
+      <VisualBrush.Visual>
+        <DrawingPresenter Width="8"
+                          Height="8">
+          <DrawingGroup>
+            <GeometryDrawing Geometry="M0,0 L2,0 2,2, 0,2Z"
+                             Brush="Transparent" />
+            <GeometryDrawing Geometry="M0,1 L2,1 2,2, 1,2 1,0 0,0Z"
+                             Brush="#19808080" />
+          </DrawingGroup>
+        </DrawingPresenter>
+      </VisualBrush.Visual>
+    </VisualBrush>
+  </Styles.Resources>
+
+  <!-- Primitives -->
+  <StyleInclude Source="avares://Avalonia.Controls.ColorPicker/Themes/Default/ColorPreviewer.xaml" />
+  <StyleInclude Source="avares://Avalonia.Controls.ColorPicker/Themes/Default/ColorSlider.xaml" />
+  <StyleInclude Source="avares://Avalonia.Controls.ColorPicker/Themes/Default/ColorSpectrum.xaml" />
+
+</Styles>

src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPreviewer.xaml

@@ -0,0 +1,86 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        xmlns:pc="using:Avalonia.Controls.Primitives.Converters"
+        x:CompileBindings="True">
+
+  <Styles.Resources>
+    <pc:AccentColorConverter x:Key="AccentColor" />
+    <converters:ToBrushConverter x:Key="ToBrush" />
+    <converters:CornerRadiusFilterConverter x:Key="RightCornerRadiusFilterConverter" Filter="TopRight, BottomRight"/>
+    <converters:CornerRadiusFilterConverter x:Key="LeftCornerRadiusFilterConverter" Filter="TopLeft, BottomLeft"/>
+  </Styles.Resources>
+
+  <Style Selector="ColorPreviewer">
+    <Setter Property="Height" Value="70" />
+    <Setter Property="CornerRadius" Value="{DynamicResource ControlCornerRadius}" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Grid ColumnDefinitions="Auto,*,Auto">
+          <!-- Left accent colors -->
+          <Grid Grid.Column="0"
+                Height="40"
+                Width="80"
+                ColumnDefinitions="*,*"
+                Margin="0,0,-10,0"
+                VerticalAlignment="Center"
+                IsVisible="{TemplateBinding ShowAccentColors}">
+            <Border Grid.Column="0"
+                    Grid.ColumnSpan="2"
+                    HorizontalAlignment="Stretch"
+                    VerticalAlignment="Stretch"
+                    Background="{StaticResource CheckeredBackgroundBrush}" />
+            <Border x:Name="AccentDec2Border"
+                    Grid.Column="0"
+                    CornerRadius="{TemplateBinding CornerRadius, Converter={StaticResource LeftCornerRadiusFilterConverter}}"
+                    Tag="-2"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='-2'}" />
+            <Border x:Name="AccentDec1Border"
+                    Grid.Column="1"
+                    Tag="-1"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='-1'}" />
+          </Grid>
+          <!-- Right accent colors -->
+          <Grid Grid.Column="2"
+                Height="40"
+                Width="80"
+                ColumnDefinitions="*,*"
+                Margin="-10,0,0,0"
+                VerticalAlignment="Center"
+                IsVisible="{TemplateBinding ShowAccentColors}">
+            <Border Grid.Column="0"
+                    Grid.ColumnSpan="2"
+                    HorizontalAlignment="Stretch"
+                    VerticalAlignment="Stretch"
+                    Background="{StaticResource CheckeredBackgroundBrush}" />
+            <Border x:Name="AccentInc1Border"
+                    Grid.Column="0"
+                    Tag="1"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='1'}" />
+            <Border x:Name="AccentInc2Border"
+                    Grid.Column="1"
+                    CornerRadius="{TemplateBinding CornerRadius, Converter={StaticResource RightCornerRadiusFilterConverter}}"
+                    Tag="2"
+                    Background="{TemplateBinding HsvColor, Converter={StaticResource AccentColor}, ConverterParameter='2'}" />
+          </Grid>
+          <!-- Must be last for drop shadow Z-index -->
+          <Border Grid.Column="1"
+                  BoxShadow="0 0 10 2 #BF000000"
+                  CornerRadius="{TemplateBinding CornerRadius}"
+                  Margin="10">
+            <Panel>
+              <Border Background="{StaticResource CheckeredBackgroundBrush}"
+                      CornerRadius="{TemplateBinding CornerRadius}" />
+              <Border x:Name="PreviewBorder"
+                      CornerRadius="{TemplateBinding CornerRadius}"
+                      Background="{TemplateBinding HsvColor, Converter={StaticResource ToBrush}}"
+                      HorizontalAlignment="Stretch"
+                      VerticalAlignment="Stretch" />
+            </Panel>
+          </Border>
+        </Grid>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+</Styles>

src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSlider.xaml

@@ -0,0 +1,194 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        x:CompileBindings="True">
+
+  <Styles.Resources>
+    <converters:CornerRadiusToDoubleConverter x:Key="TopLeftCornerRadius" Corner="TopLeft" />
+    <converters:CornerRadiusToDoubleConverter x:Key="BottomRightCornerRadius" Corner="BottomRight" />
+  </Styles.Resources>
+
+  <Style Selector="Thumb.ColorSliderThumbStyle">
+    <Setter Property="BorderThickness" Value="0" />
+    <Setter Property="Template">
+      <Setter.Value>
+        <ControlTemplate>
+          <Border Background="{TemplateBinding Background}"
+                  BorderBrush="{TemplateBinding BorderBrush}"
+                  BorderThickness="{TemplateBinding BorderThickness}"
+                  CornerRadius="10" />
+        </ControlTemplate>
+      </Setter.Value>
+    </Setter>
+  </Style>
+
+  <Style Selector="ColorSlider:horizontal">
+    <Setter Property="BorderThickness" Value="0" />
+    <Setter Property="CornerRadius" Value="10" />
+    <Setter Property="Height" Value="20" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border BorderThickness="{TemplateBinding BorderThickness}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                CornerRadius="{TemplateBinding CornerRadius}">
+          <Grid Margin="{TemplateBinding Padding}">
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{StaticResource CheckeredBackgroundBrush}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{TemplateBinding Background}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Track Name="PART_Track"
+                   HorizontalAlignment="Stretch"
+                   VerticalAlignment="Stretch"
+                   Minimum="{TemplateBinding Minimum}"
+                   Maximum="{TemplateBinding Maximum}"
+                   Value="{TemplateBinding Value, Mode=TwoWay}"
+                   IsDirectionReversed="{TemplateBinding IsDirectionReversed}"
+                   Orientation="Horizontal">
+              <Track.DecreaseButton>
+                <RepeatButton Name="PART_DecreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.DecreaseButton>
+              <Track.IncreaseButton>
+                <RepeatButton Name="PART_IncreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.IncreaseButton>
+              <Thumb Classes="ColorSliderThumbStyle"
+                     Name="ColorSliderThumb"
+                     Margin="0"
+                     Padding="0"
+                     DataContext="{TemplateBinding Value}"
+                     Height="{TemplateBinding Height}"
+                     Width="{TemplateBinding Height}" />
+            </Track>
+          </Grid>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <Style Selector="ColorSlider:vertical">
+    <Setter Property="BorderThickness" Value="0" />
+    <Setter Property="CornerRadius" Value="10" />
+    <Setter Property="Width" Value="20" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border BorderThickness="{TemplateBinding BorderThickness}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                CornerRadius="{TemplateBinding CornerRadius}">
+          <Grid Margin="{TemplateBinding Padding}">
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{StaticResource CheckeredBackgroundBrush}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Rectangle HorizontalAlignment="Stretch"
+                       VerticalAlignment="Stretch"
+                       Fill="{TemplateBinding Background}"
+                       RadiusX="{TemplateBinding CornerRadius, Converter={StaticResource TopLeftCornerRadius}}"
+                       RadiusY="{TemplateBinding CornerRadius, Converter={StaticResource BottomRightCornerRadius}}" />
+            <Track Name="PART_Track"
+                   HorizontalAlignment="Stretch"
+                   VerticalAlignment="Stretch"
+                   Minimum="{TemplateBinding Minimum}"
+                   Maximum="{TemplateBinding Maximum}"
+                   Value="{TemplateBinding Value, Mode=TwoWay}"
+                   IsDirectionReversed="{TemplateBinding IsDirectionReversed}"
+                   Orientation="Vertical">
+              <Track.DecreaseButton>
+                <RepeatButton Name="PART_DecreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.DecreaseButton>
+              <Track.IncreaseButton>
+                <RepeatButton Name="PART_IncreaseButton"
+                              Background="Transparent"
+                              Focusable="False"
+                              HorizontalAlignment="Stretch"
+                              VerticalAlignment="Stretch">
+                  <RepeatButton.Template>
+                    <ControlTemplate>
+                      <Border Name="FocusTarget"
+                              Background="Transparent"
+                              Margin="0,-10" />
+                    </ControlTemplate>
+                  </RepeatButton.Template>
+                </RepeatButton>
+              </Track.IncreaseButton>
+              <Thumb Classes="ColorSliderThumbStyle"
+                     Name="ColorSliderThumb"
+                     Margin="0"
+                     Padding="0"
+                     DataContext="{TemplateBinding Value}"
+                     Height="{TemplateBinding Width}"
+                     Width="{TemplateBinding Width}" />
+            </Track>
+          </Grid>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <!-- Normal State -->
+  <Style Selector="ColorSlider /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Background" Value="Transparent" />
+    <Setter Property="BorderBrush" Value="{DynamicResource SystemControlForegroundBaseHighBrush}" />
+    <Setter Property="BorderThickness" Value="3" />
+  </Style>
+
+  <!-- Selector/Thumb Color -->
+  <Style Selector="ColorSlider:pointerover /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Opacity" Value="0.75" />
+  </Style>
+  <Style Selector="ColorSlider:pointerover:dark-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Opacity" Value="0.7" />
+  </Style>
+  <Style Selector="ColorSlider:pointerover:light-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="Opacity" Value="0.8" />
+  </Style>
+
+  <Style Selector="ColorSlider:dark-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="BorderBrush" Value="{DynamicResource SystemControlBackgroundChromeBlackHighBrush}" />
+  </Style>
+  <Style Selector="ColorSlider:light-selector /template/ Thumb.ColorSliderThumbStyle">
+    <Setter Property="BorderBrush" Value="{DynamicResource SystemControlBackgroundChromeWhiteBrush}" />
+  </Style>
+
+</Styles>

src/Avalonia.Controls.ColorPicker/Themes/Fluent.xaml → src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSpectrum.xaml

@@ -1,7 +1,7 @@
-<Styles xmlns="https://github.com/avaloniaui"
+<Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        x:CompileBindings="True"
-        xmlns:converters="using:Avalonia.Controls.Converters">
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        x:CompileBindings="True">
 
   <Styles.Resources>
     <converters:EnumValueEqualsConverter x:Key="EnumValueEquals" />
@@ -48,7 +48,10 @@
                       Background="Transparent"
                       HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch">
-                <Panel x:Name="PART_SelectionEllipsePanel">
+                <!-- Note: ToolTip.VerticalOffset is for touch devices to keep the tip above fingers -->
+                <Panel x:Name="PART_SelectionEllipsePanel"
+                       ToolTip.VerticalOffset="-10"
+                       ToolTip.Placement="Top">
                   <Ellipse x:Name="FocusEllipse"
                            Margin="-2"
                            StrokeThickness="2"
@@ -59,13 +62,10 @@
                            StrokeThickness="2"
                            IsHitTestVisible="False"
                            HorizontalAlignment="Stretch"
-                           VerticalAlignment="Stretch"
-                           ToolTip.VerticalOffset="-20"
-                           ToolTip.Placement="Top">
-                    <ToolTip.Tip>
-                      <ToolTip x:Name="PART_ColorNameToolTip" />
-                    </ToolTip.Tip>
-                  </Ellipse>
+                           VerticalAlignment="Stretch" />
+                  <ToolTip.Tip>
+                    <!-- Set in code-behind -->
+                  </ToolTip.Tip>
                 </Panel>
               </Canvas>
               <Rectangle x:Name="BorderRectangle"
@@ -118,6 +118,9 @@
   </Style>
 
   <Style Selector="ColorSpectrum:pointerover /template/ Ellipse#SelectionEllipse">
+    <Setter Property="Opacity" Value="0.7" />
+  </Style>
+  <Style Selector="ColorSpectrum:pointerover:light-selector /template/ Ellipse#SelectionEllipse">
     <Setter Property="Opacity" Value="0.8" />
   </Style>
 

src/Avalonia.Controls.ColorPicker/Themes/Fluent/Fluent.xaml

@@ -0,0 +1,28 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+
+  <Styles.Resources>
+    <VisualBrush x:Key="CheckeredBackgroundBrush"
+                 TileMode="Tile"
+                 Stretch="Uniform"
+                 DestinationRect="0,0,8,8">
+      <VisualBrush.Visual>
+        <DrawingPresenter Width="8"
+                          Height="8">
+          <DrawingGroup>
+            <GeometryDrawing Geometry="M0,0 L2,0 2,2, 0,2Z"
+                             Brush="Transparent" />
+            <GeometryDrawing Geometry="M0,1 L2,1 2,2, 1,2 1,0 0,0Z"
+                             Brush="#19808080" />
+          </DrawingGroup>
+        </DrawingPresenter>
+      </VisualBrush.Visual>
+    </VisualBrush>
+  </Styles.Resources>
+
+  <!-- Primitives -->
+  <StyleInclude Source="avares://Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPreviewer.xaml" />
+  <StyleInclude Source="avares://Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSlider.xaml" />
+  <StyleInclude Source="avares://Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSpectrum.xaml" />
+
+</Styles>

src/Avalonia.Controls/Converters/CornerRadiusFilterConverter.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Globalization;
-
 using Avalonia.Data.Converters;
 
 namespace Avalonia.Controls.Converters
@@ -22,7 +21,12 @@ namespace Avalonia.Controls.Converters
         /// </summary>
         public double Scale { get; set; } = 1;
 
-        public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+        /// <inheritdoc/>
+        public object? Convert(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
         {
             if (!(value is CornerRadius radius))
             {
@@ -36,7 +40,12 @@ namespace Avalonia.Controls.Converters
                 Filter.HasAllFlags(Corners.BottomLeft) ? radius.BottomLeft * Scale : 0);
         }
 
-        public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+        /// <inheritdoc/>
+        public object? ConvertBack(
+            object? value,
+            Type targetType,
+            object? parameter,
+            CultureInfo culture)
         {
             throw new NotImplementedException();
         }

src/Avalonia.Controls/Documents/IInlineHost.cs

@@ -0,0 +1,11 @@
+using Avalonia.LogicalTree;
+
+namespace Avalonia.Controls.Documents
+{
+    internal interface IInlineHost : ILogical
+    {
+        void AddVisualChild(IControl child);
+
+        void Invalidate();
+    }
+}

src/Avalonia.Controls/Documents/Inline.cs

@@ -2,9 +2,8 @@ using System.Collections.Generic;
 using System.Text;
 using Avalonia.Media;
 using Avalonia.Media.TextFormatting;
-using Avalonia.Utilities;
 
-namespace Avalonia.Controls.Documents 
+namespace Avalonia.Controls.Documents
 {
     /// <summary>
     /// Inline element.
@@ -45,9 +44,9 @@ namespace Avalonia.Controls.Documents
             set { SetValue(BaselineAlignmentProperty, value); }
         }
 
-        internal abstract int BuildRun(StringBuilder stringBuilder, IList<ValueSpan<TextRunProperties>> textStyleOverrides, int firstCharacterIndex);
+        internal abstract void BuildTextRun(IList<TextRun> textRuns);
 
-        internal abstract int AppendText(StringBuilder stringBuilder);
+        internal abstract void AppendText(StringBuilder stringBuilder);
 
         protected TextRunProperties CreateTextRunProperties()
         {
@@ -63,7 +62,7 @@ namespace Avalonia.Controls.Documents
             {
                 case nameof(TextDecorations):
                 case nameof(BaselineAlignment):
-                    Invalidate();
+                    InlineHost?.Invalidate();
                     break;
             }
         }

src/Avalonia.Controls/Documents/InlineCollection.cs

@@ -12,29 +12,37 @@ namespace Avalonia.Controls.Documents
     [WhitespaceSignificantCollection]
     public class InlineCollection : AvaloniaList<Inline>
     {
+        private readonly IInlineHost? _host;
         private string? _text = string.Empty;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="InlineCollection"/> class.
         /// </summary>
-        public InlineCollection(ILogical parent) : base(0)
+        public InlineCollection(ILogical parent) : this(parent, null) { }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="InlineCollection"/> class.
+        /// </summary>
+        internal InlineCollection(ILogical parent, IInlineHost? host = null) : base(0)
         {
+            _host = host;
+
             ResetBehavior = ResetBehavior.Remove;
             
             this.ForEachItem(
                 x =>
                 {
                     ((ISetLogicalParent)x).SetParent(parent);
-                    x.Invalidated += Invalidate;
-                    Invalidate();
+                    x.InlineHost = host;
+                    host?.Invalidate();
                 },
                 x =>
                 {
                     ((ISetLogicalParent)x).SetParent(null);
-                    x.Invalidated -= Invalidate;
-                    Invalidate();
+                    x.InlineHost = host;
+                    host?.Invalidate();
                 },
-                () => throw new NotSupportedException());
+                () => throw new NotSupportedException());         
         }
 
         public bool HasComplexContent => Count > 0;
@@ -96,12 +104,22 @@ namespace Avalonia.Controls.Documents
             }
         }
 
+        public void Add(IControl child)
+        {
+            var implicitRun = new InlineUIContainer(child);
+
+            Add(implicitRun);
+        }
+
         public override void Add(Inline item)
         {
             if (!HasComplexContent)
             {
-                base.Add(new Run(_text));
-                
+                if (!string.IsNullOrEmpty(_text))
+                {
+                    base.Add(new Run(_text));
+                }
+                             
                 _text = string.Empty;
             }
             
@@ -112,11 +130,19 @@ namespace Avalonia.Controls.Documents
         /// Raised when an inline in the collection changes.
         /// </summary>
         public event EventHandler? Invalidated;
-        
+
         /// <summary>
         /// Raises the <see cref="Invalidated"/> event.
         /// </summary>
-        protected void Invalidate() => Invalidated?.Invoke(this, EventArgs.Empty);
+        protected void Invalidate()
+        {
+            if(_host != null)
+            {
+                _host.Invalidate();
+            }
+
+            Invalidated?.Invoke(this, EventArgs.Empty);
+        }
 
         private void Invalidate(object? sender, EventArgs e) => Invalidate();
     }

src/Avalonia.Controls/Documents/InlineUIContainer.cs

@@ -0,0 +1,125 @@
+using System.Collections.Generic;
+using System.Text;
+using Avalonia.Media;
+using Avalonia.Media.TextFormatting;
+using Avalonia.Metadata;
+using Avalonia.Utilities;
+
+namespace Avalonia.Controls.Documents
+{
+    /// <summary>
+    /// InlineUIContainer - a wrapper for embedded UIElements in text 
+    /// flow content inline collections
+    /// </summary>
+    public class InlineUIContainer : Inline
+    {
+        /// <summary>
+        /// Defines the <see cref="Child"/> property.
+        /// </summary>
+        public static readonly StyledProperty<IControl> ChildProperty =
+            AvaloniaProperty.Register<InlineUIContainer, IControl>(nameof(Child));
+
+        static InlineUIContainer()
+        {
+            BaselineAlignmentProperty.OverrideDefaultValue<InlineUIContainer>(BaselineAlignment.Top);
+        }
+
+        /// <summary>
+        /// Initializes a new instance of InlineUIContainer element.
+        /// </summary>
+        /// <remarks>
+        /// The purpose of this element is to be a wrapper for UIElements
+        /// when they are embedded into text flow - as items of
+        /// InlineCollections.
+        /// </remarks>
+        public InlineUIContainer()
+        {
+        }
+
+        /// <summary>
+        /// Initializes an InlineBox specifying its child UIElement
+        /// </summary>
+        /// <param name="child">
+        /// UIElement set as a child of this inline item
+        /// </param>
+        public InlineUIContainer(IControl child)
+        {
+            Child = child;
+        }
+
+        /// <summary>
+        /// The content spanned by this TextElement.
+        /// </summary>
+        [Content]
+        public IControl Child
+        {
+            get => GetValue(ChildProperty);
+            set => SetValue(ChildProperty, value);
+        }
+
+        internal override void BuildTextRun(IList<TextRun> textRuns)
+        {
+            if(InlineHost == null)
+            {
+                return;
+            }
+
+            ((ISetLogicalParent)Child).SetParent(InlineHost);
+
+            InlineHost.AddVisualChild(Child);
+
+            textRuns.Add(new InlineRun(Child, CreateTextRunProperties()));
+        }
+
+        internal override void AppendText(StringBuilder stringBuilder)
+        {
+        }
+
+        private class InlineRun : DrawableTextRun
+        {
+            public InlineRun(IControl control, TextRunProperties properties)
+            {
+                Control = control;
+                Properties = properties;
+            }
+
+            public IControl Control { get; }
+
+            public override TextRunProperties? Properties { get; }
+
+            public override Size Size
+            {
+                get
+                {
+                    if (!Control.IsMeasureValid)
+                    {
+                        Control.Measure(Size.Infinity);
+                    }
+
+                    return Control.DesiredSize;
+                }
+            }
+
+            public override double Baseline
+            {
+                get
+                {
+                    double baseline = Size.Height;
+                    double baselineOffsetValue = Control.GetValue<double>(TextBlock.BaselineOffsetProperty);
+
+                    if (!MathUtilities.IsZero(baselineOffsetValue))
+                    {
+                        baseline = baselineOffsetValue;
+                    }
+
+                    return -baseline;
+                }
+            }
+
+            public override void Draw(DrawingContext drawingContext, Point origin)
+            {             
+                Control.Arrange(new Rect(origin, Size));                
+            }
+        }
+    }
+}

src/Avalonia.Controls/Documents/LineBreak.cs

@@ -1,9 +1,9 @@
 using System;
 using System.Collections.Generic;
 using System.Text;
+using Avalonia.LogicalTree;
 using Avalonia.Media.TextFormatting;
 using Avalonia.Metadata;
-using Avalonia.Utilities;
 
 namespace Avalonia.Controls.Documents 
 {
@@ -20,24 +20,14 @@ namespace Avalonia.Controls.Documents
         {
         }
 
-        internal override int BuildRun(StringBuilder stringBuilder,
-            IList<ValueSpan<TextRunProperties>> textStyleOverrides, int firstCharacterIndex)
+        internal override void BuildTextRun(IList<TextRun> textRuns)
         {
-            var length = AppendText(stringBuilder);
-
-            textStyleOverrides.Add(new ValueSpan<TextRunProperties>(firstCharacterIndex, length,
-                CreateTextRunProperties()));
-
-            return length;
+            textRuns.Add(new TextEndOfLine());
         }
 
-        internal override int AppendText(StringBuilder stringBuilder)
+        internal override void AppendText(StringBuilder stringBuilder)
         {
-            var text = Environment.NewLine;
-
-            stringBuilder.Append(text);
-
-            return text.Length;
+            stringBuilder.Append(Environment.NewLine);
         }
     }
 }

src/Avalonia.Controls/Documents/Run.cs

@@ -4,7 +4,6 @@ using System.Text;
 using Avalonia.Data;
 using Avalonia.Media.TextFormatting;
 using Avalonia.Metadata;
-using Avalonia.Utilities;
 
 namespace Avalonia.Controls.Documents
 {
@@ -51,24 +50,22 @@ namespace Avalonia.Controls.Documents
             set { SetValue (TextProperty, value); }
         }
 
-        internal override int BuildRun(StringBuilder stringBuilder,
-            IList<ValueSpan<TextRunProperties>> textStyleOverrides, int firstCharacterIndex)
+        internal override void BuildTextRun(IList<TextRun> textRuns)
         {
-            var length = AppendText(stringBuilder);
+            var text = (Text ?? "").AsMemory();
 
-            textStyleOverrides.Add(new ValueSpan<TextRunProperties>(firstCharacterIndex, length,
-                CreateTextRunProperties()));
+            var textRunProperties = CreateTextRunProperties();           
 
-            return length;
+            var textCharacters = new TextCharacters(text, textRunProperties);
+
+            textRuns.Add(textCharacters);
         }
 
-        internal override int AppendText(StringBuilder stringBuilder)
+        internal override void AppendText(StringBuilder stringBuilder)
         {
             var text = Text ?? "";
 
             stringBuilder.Append(text);
-
-            return text.Length;
         }
 
         protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)
@@ -78,7 +75,7 @@ namespace Avalonia.Controls.Documents
             switch (change.Property.Name)
             {
                 case nameof(Text):
-                    Invalidate();
+                    InlineHost?.Invalidate();
                     break;
             }
         }

src/Avalonia.Controls/Documents/Span.cs

@@ -1,8 +1,8 @@
+using System;
 using System.Collections.Generic;
 using System.Text;
 using Avalonia.Media.TextFormatting;
 using Avalonia.Metadata;
-using Avalonia.Utilities;
 
 namespace Avalonia.Controls.Documents
 {
@@ -25,8 +25,7 @@ namespace Avalonia.Controls.Documents
         public Span()
         {
             Inlines = new InlineCollection(this);
-
-            Inlines.Invalidated += (s, e) => Invalidate();
+            Inlines.Invalidated += (s, e) => InlineHost?.Invalidate();
         }
 
         /// <summary>
@@ -35,61 +34,42 @@ namespace Avalonia.Controls.Documents
         [Content]
         public InlineCollection Inlines { get; }
 
-        internal override int BuildRun(StringBuilder stringBuilder, IList<ValueSpan<TextRunProperties>> textStyleOverrides, int firstCharacterIndex)
+        internal override void BuildTextRun(IList<TextRun> textRuns)
         {
-            var length = 0;
-
             if (Inlines.HasComplexContent)
             {
                 foreach (var inline in Inlines)
                 {
-                    var inlineLength = inline.BuildRun(stringBuilder, textStyleOverrides, firstCharacterIndex);
-
-                    firstCharacterIndex += inlineLength;
-
-                    length += inlineLength;
+                    inline.BuildTextRun(textRuns);
                 }
             }
             else
             {
-                if (Inlines.Text == null)
+                if (Inlines.Text is string text)
                 {
-                    return length;
-                }
-                
-                stringBuilder.Append(Inlines.Text);
+                    var textRunProperties = CreateTextRunProperties();
 
-                length = Inlines.Text.Length;
+                    var textCharacters = new TextCharacters(text.AsMemory(), textRunProperties);
 
-                textStyleOverrides.Add(new ValueSpan<TextRunProperties>(firstCharacterIndex, length,
-                    CreateTextRunProperties()));
+                    textRuns.Add(textCharacters);
+                }          
             }
-
-            return length;
         }
 
-        internal override int AppendText(StringBuilder stringBuilder)
+        internal override void AppendText(StringBuilder stringBuilder)
         {
             if (Inlines.HasComplexContent)
             {
-                var length = 0;
-
                 foreach (var inline in Inlines)
                 {
-                    length += inline.AppendText(stringBuilder);
+                    inline.AppendText(stringBuilder);
                 }
-
-                return length;
             }
 
-            if (Inlines.Text == null)
+            if (Inlines.Text is string text)
             {
-                return 0;
+                stringBuilder.Append(text);
             }
-         
-            stringBuilder.Append(Inlines.Text);
-
-            return Inlines.Text.Length;
         }
     }
 }

src/Avalonia.Controls/Documents/TextElement.cs

@@ -1,5 +1,4 @@
-using System;
-using Avalonia.Media;
+using Avalonia.Media;
 
 namespace Avalonia.Controls.Documents
 {
@@ -251,10 +250,7 @@ namespace Avalonia.Controls.Documents
             control.SetValue(ForegroundProperty, value);
         }
 
-        /// <summary>
-        /// Raised when the visual representation of the text element changes.
-        /// </summary>
-        public event EventHandler? Invalidated;
+        internal IInlineHost? InlineHost { get; set; }
 
         protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)
         {
@@ -269,14 +265,9 @@ namespace Avalonia.Controls.Documents
                 case nameof(FontWeight):
                 case nameof(FontStretch):
                 case nameof(Foreground):
-                    Invalidate();
+                    InlineHost?.Invalidate();
                     break;
             }
         }
-
-        /// <summary>
-        /// Raises the <see cref="Invalidate"/> event.
-        /// </summary>
-        protected void Invalidate() => Invalidated?.Invoke(this, EventArgs.Empty);
     }
 }

src/Avalonia.Controls/ItemsControl.cs

@@ -518,7 +518,7 @@ namespace Avalonia.Controls
                 }
 
                 c = result;
-            } while (c != null && c != from);
+            } while (c != null && c != from && direction != NavigationDirection.First && direction != NavigationDirection.Last);
 
             return null;
         }

src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs

@@ -417,7 +417,7 @@ namespace Avalonia.Controls.Platform
 
         protected internal virtual void MenuOpened(object? sender, RoutedEventArgs e)
         {
-            if (e.Source == Menu)
+            if (e.Source is Menu)
             {
                 Menu?.MoveSelection(NavigationDirection.First, true);
             }

src/Avalonia.Controls/Presenters/TextPresenter.cs

@@ -511,28 +511,39 @@ namespace Avalonia.Controls.Presenters
             
             InvalidateMeasure();
         }
-        
+
+
         protected override Size MeasureOverride(Size availableSize)
         {
+            if (string.IsNullOrEmpty(Text))
+            {
+                return new Size();
+            }
+
             _constraint = availableSize;
-            
+
             _textLayout = null;
-            
+
             InvalidateArrange();
 
-            var measuredSize = PixelSize.FromSize(TextLayout.Bounds.Size, 1);
-            
-            return new Size(measuredSize.Width, measuredSize.Height);
+            var measuredSize = TextLayout.Bounds.Size;
+
+            return measuredSize;
         }
 
         protected override Size ArrangeOverride(Size finalSize)
         {
+            if (finalSize.Width < TextLayout.Bounds.Width)
+            {
+                finalSize = finalSize.WithWidth(TextLayout.Bounds.Width);
+            }
+
             if (MathUtilities.AreClose(_constraint.Width, finalSize.Width))
             {
                 return finalSize;
             }
 
-            _constraint = new Size(finalSize.Width, Math.Ceiling(finalSize.Height));
+            _constraint = new Size(finalSize.Width, double.PositiveInfinity);
 
             _textLayout = null;
 
@@ -662,7 +673,7 @@ namespace Avalonia.Controls.Presenters
 
                     caretIndex = characterHit.FirstCharacterIndex + characterHit.TrailingLength;
 
-                    if (textLine.NewLineLength > 0 && caretIndex == textLine.FirstTextSourceIndex + textLine.Length)
+                    if (textLine.TrailingWhitespaceLength > 0 && caretIndex == textLine.FirstTextSourceIndex + textLine.Length)
                     {
                         characterHit = new CharacterHit(caretIndex);
                     }

src/Avalonia.Controls/TextBlock.cs

@@ -14,7 +14,7 @@ namespace Avalonia.Controls
     /// <summary>
     /// A control that displays a block of text.
     /// </summary>
-    public class TextBlock : Control
+    public class TextBlock : Control, IInlineHost
     {
         /// <summary>
         /// Defines the <see cref="Background"/> property.
@@ -155,9 +155,7 @@ namespace Avalonia.Controls
         /// </summary>
         public TextBlock()
         {
-            Inlines = new InlineCollection(this);
-
-            Inlines.Invalidated += InlinesChanged;
+            Inlines = new InlineCollection(this, this);
         }
 
         /// <summary>
@@ -211,7 +209,7 @@ namespace Avalonia.Controls
         }
 
         /// <summary>
-        /// Gets or sets the inlines.
+        /// Gets the inlines.
         /// </summary>
         [Content]
         public InlineCollection Inlines { get; }
@@ -552,38 +550,41 @@ namespace Avalonia.Controls
         /// <returns>A <see cref="TextLayout"/> object.</returns>
         protected virtual TextLayout CreateTextLayout(Size constraint, string? text)
         {
-            List<ValueSpan<TextRunProperties>>? textStyleOverrides = null;
+            var defaultProperties = new GenericTextRunProperties(
+                new Typeface(FontFamily, FontStyle, FontWeight, FontStretch),
+                FontSize,
+                TextDecorations,
+                Foreground);
+
+            var paragraphProperties = new GenericTextParagraphProperties(FlowDirection, TextAlignment, true, false,
+                defaultProperties, TextWrapping, LineHeight, 0);
+
+            ITextSource textSource;
 
             if (Inlines.HasComplexContent)
             {
-                textStyleOverrides = new List<ValueSpan<TextRunProperties>>(Inlines.Count);
-
-                var textPosition = 0;
-                var stringBuilder = new StringBuilder();
+                var textRuns = new List<TextRun>();
 
                 foreach (var inline in Inlines)
                 {
-                    textPosition += inline.BuildRun(stringBuilder, textStyleOverrides, textPosition);
+                    inline.BuildTextRun(textRuns);
                 }
 
-                text = stringBuilder.ToString();
+                textSource = new InlinesTextSource(textRuns);
+            }
+            else
+            {
+                textSource = new SimpleTextSource((text ?? "").AsMemory(), defaultProperties);
             }
 
             return new TextLayout(
-                text ?? string.Empty,
-                new Typeface(FontFamily, FontStyle, FontWeight, FontStretch),
-                FontSize,
-                Foreground ?? Brushes.Transparent,
-                TextAlignment,
-                TextWrapping,
+                textSource,
+                paragraphProperties,
                 TextTrimming,
-                TextDecorations,
-                FlowDirection,
                 constraint.Width,
                 constraint.Height,
                 maxLines: MaxLines,
-                lineHeight: LineHeight,
-                textStyleOverrides: textStyleOverrides);
+                lineHeight: LineHeight);
         }
 
         /// <summary>
@@ -592,7 +593,7 @@ namespace Avalonia.Controls
         protected void InvalidateTextLayout()
         {
             _textLayout = null;
-            
+
             InvalidateMeasure();
         }
 
@@ -603,28 +604,35 @@ namespace Avalonia.Controls
                 return new Size();
             }
 
-            var padding = Padding;
-            
+            var scale = LayoutHelper.GetLayoutScale(this);
+
+            var padding = LayoutHelper.RoundLayoutThickness(Padding, scale, scale);
+
             _constraint = availableSize.Deflate(padding);
-            
+
             _textLayout = null;
 
             InvalidateArrange();
 
-            var measuredSize = PixelSize.FromSize(TextLayout.Bounds.Size, 1);
+            var measuredSize = TextLayout.Bounds.Size.Inflate(padding);
 
-            return new Size(measuredSize.Width, measuredSize.Height).Inflate(padding);
+            return measuredSize;
         }
 
         protected override Size ArrangeOverride(Size finalSize)
         {
+            if(finalSize.Width < TextLayout.Bounds.Width)
+            {
+                finalSize = finalSize.WithWidth(TextLayout.Bounds.Width);
+            }
+
             if (MathUtilities.AreClose(_constraint.Width, finalSize.Width))
             {
                 return finalSize;
             }
-            
-            _constraint = new Size(finalSize.Width, Math.Ceiling(finalSize.Height));
-            
+
+            _constraint = new Size(finalSize.Width, double.PositiveInfinity);
+
             _textLayout = null;
 
             return finalSize;
@@ -660,8 +668,6 @@ namespace Avalonia.Controls
                 case nameof (Padding):
                 case nameof (LineHeight):
                 case nameof (MaxLines):
-                    
-                case nameof (InlinesProperty):
 
                 case nameof (Text):
                 case nameof (TextDecorations):
@@ -673,9 +679,83 @@ namespace Avalonia.Controls
             }
         }
 
- 		private void InlinesChanged(object? sender, EventArgs e)
+        private void InlinesChanged(object? sender, EventArgs e)
+        {
+            InvalidateTextLayout();
+        }
+
+        void IInlineHost.AddVisualChild(IControl child)
+        {
+            if (child.VisualParent == null)
+            {
+                VisualChildren.Add(child);
+            }            
+        }
+
+        void IInlineHost.Invalidate()
         {
             InvalidateTextLayout();
         }
+
+        private readonly struct InlinesTextSource : ITextSource
+        {
+            private readonly IReadOnlyList<TextRun> _textRuns;
+
+            public InlinesTextSource(IReadOnlyList<TextRun> textRuns)
+            {
+                _textRuns = textRuns;
+            }
+
+            public TextRun? GetTextRun(int textSourceIndex)
+            {
+                var currentPosition = 0;
+
+                foreach (var textRun in _textRuns)
+                {
+                    if(textRun.TextSourceLength == 0)
+                    {
+                        continue;
+                    }
+
+                    if(currentPosition >= textSourceIndex)
+                    {
+                        return textRun;
+                    }
+
+                    currentPosition += textRun.TextSourceLength;
+                }
+
+                return null;
+            }
+        }
+
+        private readonly struct SimpleTextSource : ITextSource
+        {
+            private readonly ReadOnlySlice<char> _text;
+            private readonly TextRunProperties _defaultProperties;
+
+            public SimpleTextSource(ReadOnlySlice<char> text, TextRunProperties defaultProperties)
+            {
+                _text = text;
+                _defaultProperties = defaultProperties;
+            }
+
+            public TextRun? GetTextRun(int textSourceIndex)
+            {
+                if (textSourceIndex > _text.Length)
+                {
+                    return null;
+                }
+
+                var runText = _text.Skip(textSourceIndex);
+
+                if (runText.IsEmpty)
+                {
+                    return null;
+                }
+
+                return new TextCharacters(runText, _defaultProperties);
+            }
+        }
     }
 }

src/Avalonia.Controls/Viewbox.cs

@@ -14,7 +14,7 @@ namespace Avalonia.Controls
         /// Defines the <see cref="Stretch"/> property.
         /// </summary>
         public static readonly StyledProperty<Stretch> StretchProperty =
-            AvaloniaProperty.Register<Image, Stretch>(nameof(Stretch), Stretch.Uniform);
+            AvaloniaProperty.Register<Viewbox, Stretch>(nameof(Stretch), Stretch.Uniform);
 
         /// <summary>
         /// Defines the <see cref="StretchDirection"/> property.

src/Avalonia.Diagnostics/Diagnostics/ViewModels/AvaloniaPropertyViewModel.cs

@@ -1,13 +1,17 @@
+using System;
+using Avalonia.Data;
+using Avalonia.Media;
+
 namespace Avalonia.Diagnostics.ViewModels
 {
     internal class AvaloniaPropertyViewModel : PropertyViewModel
     {
         private readonly AvaloniaObject _target;
-        private System.Type _assignedType;
+        private Type _assignedType;
         private object? _value;
         private string _priority;
         private string _group;
-        private readonly System.Type _propertyType;
+        private readonly Type _propertyType;
 
 #nullable disable
         // Remove "nullable disable" after MemberNotNull will work on our CI.
@@ -28,13 +32,9 @@ namespace Avalonia.Diagnostics.ViewModels
         public AvaloniaProperty Property { get; }
         public override object Key => Property;
         public override string Name { get; }
-        public override bool? IsAttached => 
-            Property.IsAttached;
-
-        public override string Priority =>
-            _priority;
-
-        public override System.Type AssignedType => _assignedType;
+        public override bool? IsAttached => Property.IsAttached;
+        public override string Priority => _priority;
+        public override Type AssignedType => _assignedType;
 
         public override string? Value
         {
@@ -53,30 +53,58 @@ namespace Avalonia.Diagnostics.ViewModels
 
         public override string Group => _group;
 
-        public override System.Type? DeclaringType { get; }
-        public override System.Type PropertyType => _propertyType;
+        public override Type? DeclaringType { get; }
+        public override Type PropertyType => _propertyType;
 
         // [MemberNotNull(nameof(_type), nameof(_group), nameof(_priority))]
         public override void Update()
         {
             if (Property.IsDirect)
             {
-                RaiseAndSetIfChanged(ref _value, _target.GetValue(Property), nameof(Value));
-                RaiseAndSetIfChanged(ref _assignedType,_value?.GetType() ?? Property.PropertyType, nameof(AssignedType));
+                object? value;
+                Type? valueType = null;
+
+                try
+                {
+                    value = _target.GetValue(Property);
+                    valueType = value?.GetType();
+                }
+                catch (Exception e)
+                {
+                    value = e.GetBaseException();
+                }
+
+                RaiseAndSetIfChanged(ref _value, value, nameof(Value));
+                RaiseAndSetIfChanged(ref _assignedType, valueType ?? Property.PropertyType, nameof(AssignedType));
                 RaiseAndSetIfChanged(ref _priority, "Direct", nameof(Priority));
 
                 _group = "Properties";
             }
             else
             {
-                var val = _target.GetDiagnostic(Property);
+                object? value;
+                Type? valueType = null;
+                BindingPriority? priority = null;
+
+                try
+                {
+                    var diag = _target.GetDiagnostic(Property);
+
+                    value = diag.Value;
+                    valueType = value?.GetType();
+                    priority = diag.Priority;
+                }
+                catch (Exception e)
+                {
+                    value = e.GetBaseException();
+                }
 
-                RaiseAndSetIfChanged(ref _value, val?.Value, nameof(Value));
-                RaiseAndSetIfChanged(ref _assignedType, _value?.GetType() ?? Property.PropertyType, nameof(AssignedType));
+                RaiseAndSetIfChanged(ref _value, value, nameof(Value));
+                RaiseAndSetIfChanged(ref _assignedType, valueType ?? Property.PropertyType, nameof(AssignedType));
 
-                if (val != null)
+                if (priority != null)
                 {
-                    RaiseAndSetIfChanged(ref _priority, val.Priority.ToString(), nameof(Priority));
+                    RaiseAndSetIfChanged(ref _priority, priority.ToString()!, nameof(Priority));
                     RaiseAndSetIfChanged(ref _group, IsAttached == true ? "Attached Properties" : "Properties", nameof(Group));
                 }
                 else

src/Avalonia.Diagnostics/Diagnostics/ViewModels/ClrPropertyViewModel.cs

@@ -1,13 +1,15 @@
-using System.Reflection;
+using System;
+using System.Reflection;
+using Avalonia.Media;
 
 namespace Avalonia.Diagnostics.ViewModels
 {
     internal class ClrPropertyViewModel : PropertyViewModel
     {
         private readonly object _target;
-        private System.Type _assignedType;
+        private Type _assignedType;
         private object? _value;
-        private readonly System.Type _propertyType;
+        private readonly Type _propertyType;
 
 #nullable disable
         // Remove "nullable disable" after MemberNotNull will work on our CI.
@@ -25,6 +27,7 @@ namespace Avalonia.Diagnostics.ViewModels
             {
                 Name = property.DeclaringType.Name + '.' + property.Name;
             }
+
             DeclaringType = property.DeclaringType;
             _propertyType = property.PropertyType;
 
@@ -36,10 +39,10 @@ namespace Avalonia.Diagnostics.ViewModels
         public override string Name { get; }
         public override string Group => "CLR Properties";
 
-        public override System.Type AssignedType => _assignedType;
-        public override  System.Type PropertyType => _propertyType;
+        public override Type AssignedType => _assignedType;
+        public override Type PropertyType => _propertyType;
 
-        public override string? Value 
+        public override string? Value
         {
             get => ConvertToString(_value);
             set
@@ -54,20 +57,30 @@ namespace Avalonia.Diagnostics.ViewModels
             }
         }
 
-        public override string Priority => 
-            string.Empty;
+        public override string Priority => string.Empty;
 
-        public override bool? IsAttached => 
-            default;
+        public override bool? IsAttached => default;
 
-        public override System.Type? DeclaringType { get; }
+        public override Type? DeclaringType { get; }
 
         // [MemberNotNull(nameof(_type))]
         public override void Update()
         {
-            var val = Property.GetValue(_target);
-            RaiseAndSetIfChanged(ref _value, val, nameof(Value));
-            RaiseAndSetIfChanged(ref _assignedType, _value?.GetType() ?? Property.PropertyType, nameof(AssignedType));
+            object? value;
+            Type? valueType = null;
+
+            try
+            {
+                value = Property.GetValue(_target);
+                valueType = value?.GetType();
+            }
+            catch (Exception e)
+            {
+                value = e.GetBaseException();
+            }
+
+            RaiseAndSetIfChanged(ref _value, value, nameof(Value));
+            RaiseAndSetIfChanged(ref _assignedType, valueType ?? Property.PropertyType, nameof(AssignedType));
             RaisePropertyChanged(nameof(Type));
         }
     }

src/Avalonia.Themes.Default/Controls/DataValidationErrors.xaml

@@ -1,9 +1,13 @@
 <Style xmlns="https://github.com/avaloniaui" 
-       Selector="DataValidationErrors">
+       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+       Selector="DataValidationErrors"
+       x:CompileBindings="True"
+       x:DataType="DataValidationErrors">
   <Setter Property="Template">
     <ControlTemplate>
       <DockPanel LastChildFill="True">
-        <ContentControl DockPanel.Dock="Right"
+        <ContentControl x:DataType="DataValidationErrors"
+                        DockPanel.Dock="Right"
                         ContentTemplate="{TemplateBinding ErrorTemplate}"
                         DataContext="{TemplateBinding Owner}"
                         Content="{Binding (DataValidationErrors.Errors)}"
@@ -30,7 +34,7 @@
           </Style>
         </Canvas.Styles>
         <ToolTip.Tip>
-          <ItemsControl Items="{Binding}"/>
+          <ItemsControl x:DataType="DataValidationErrors" Items="{Binding}"/>
         </ToolTip.Tip>
         <Path Data="M14,7 A7,7 0 0,0 0,7 M0,7 A7,7 0 1,0 14,7 M7,3l0,5 M7,9l0,2" Stroke="{DynamicResource ErrorBrush}" StrokeThickness="2"/>
       </Canvas>

src/Avalonia.Themes.Default/Controls/NativeMenuBar.xaml

@@ -4,6 +4,7 @@
        Selector="NativeMenuBar">
   <Style.Resources>
     <local:InverseBooleanValueConverter x:Key="AvaloniaThemesDefaultNativeMenuBarInverseBooleanValueConverter" Default="True"/>
+    <local:IBitmapToImageConverter x:Key="AvaloniaThemesDefaultNativeMenuBarIBitmapToImageConverterr"/>
   </Style.Resources>
   <Setter Property="Template">
     <ControlTemplate>
@@ -18,6 +19,8 @@
             <Setter Property="Command" Value="{Binding Command}"/>
             <Setter Property="CommandParameter" Value="{Binding CommandParameter}"/>
             <Setter Property="(NativeMenuBar.EnableMenuItemClickForwarding)" Value="True"/>
+            <!--NativeMenuItem is IBitmap and MenuItem is Image-->
+            <Setter Property="Icon" Value="{Binding Icon , Converter={StaticResource AvaloniaThemesDefaultNativeMenuBarIBitmapToImageConverterr}}"/>
           </Style>
         </Menu.Styles>
       </Menu>

src/Avalonia.Themes.Default/IBitmapToImageConverter.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Avalonia.Controls;
+using Avalonia.Data.Converters;
+using Avalonia.Media.Imaging;
+
+namespace Avalonia.Themes.Default
+{
+    internal class IBitmapToImageConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            if (value != null && value is IBitmap bm)
+                return new Image { Source=bm };
+                
+            return null;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            throw new NotImplementedException();
+        }
+    }
+}

src/Avalonia.Themes.Fluent/Controls/NativeMenuBar.xaml

@@ -4,12 +4,13 @@
        x:CompileBindings="True"
        Selector="NativeMenuBar">
   <Style.Resources>
-    <local:InverseBooleanValueConverter x:Key="AvaloniaThemesDefaultNativeMenuBarInverseBooleanValueConverter" Default="True"/>
+    <local:InverseBooleanValueConverter x:Key="AvaloniaThemesFluentNativeMenuBarInverseBooleanValueConverter" Default="True"/>
+    <local:IBitmapToImageConverter x:Key="AvaloniaThemesFluentNativeMenuBarIBitmapToImageConverter"/>
   </Style.Resources>
   <Setter Property="Template">
     <ControlTemplate>
       <Menu
-        IsVisible="{Binding $parent[TopLevel].(NativeMenu.IsNativeMenuExported), Converter={StaticResource AvaloniaThemesDefaultNativeMenuBarInverseBooleanValueConverter}}"
+        IsVisible="{Binding $parent[TopLevel].(NativeMenu.IsNativeMenuExported), Converter={StaticResource AvaloniaThemesFluentNativeMenuBarInverseBooleanValueConverter}}"
         Items="{Binding $parent[TopLevel].(NativeMenu.Menu).Items}">
         <Menu.Styles>
           <Style x:CompileBindings="False" Selector="MenuItem">
@@ -19,6 +20,8 @@
             <Setter Property="Command" Value="{Binding Command}"/>
             <Setter Property="CommandParameter" Value="{Binding CommandParameter}"/>
             <Setter Property="(NativeMenuBar.EnableMenuItemClickForwarding)" Value="True"/>
+            <!--NativeMenuItem is IBitmap and MenuItem is Image-->
+            <Setter Property="Icon" Value="{Binding Icon , Converter={StaticResource AvaloniaThemesFluentNativeMenuBarIBitmapToImageConverter}}"/>
           </Style>
         </Menu.Styles>
       </Menu>

src/Avalonia.Themes.Fluent/IBitmapToImageConverter.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Avalonia.Controls;
+using Avalonia.Data.Converters;
+using Avalonia.Media.Imaging;
+
+namespace Avalonia.Themes.Fluent
+{
+    internal class IBitmapToImageConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            if (value != null && value is IBitmap bm)
+                return new Image { Source=bm };
+                
+            return null;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            throw new NotImplementedException();
+        }
+    }
+}

src/Markup/Avalonia.Markup.Xaml/MarkupExtensions/StaticResourceExtension.cs

@@ -39,17 +39,11 @@ namespace Avalonia.Markup.Xaml.MarkupExtensions
                 targetType = setter.Property.PropertyType;
             }
 
-            // Look upwards though the ambient context for IResourceHosts and IResourceProviders
+            // Look upwards though the ambient context for IResourceNodes
             // which might be able to give us the resource.
-            foreach (var e in stack.Parents)
+            foreach (var parent in stack.Parents)
             {
-                object value;
-
-                if (e is IResourceHost host && host.TryGetResource(ResourceKey, out value))
-                {
-                    return ColorToBrushConverter.Convert(value, targetType);
-                }
-                else if (e is IResourceProvider provider && provider.TryGetResource(ResourceKey, out value))
+                if (parent is IResourceNode node && node.TryGetResource(ResourceKey, out var value))
                 {
                     return ColorToBrushConverter.Convert(value, targetType);
                 }
@@ -58,7 +52,11 @@ namespace Avalonia.Markup.Xaml.MarkupExtensions
             if (provideTarget.TargetObject is IControl target &&
                 provideTarget.TargetProperty is PropertyInfo property)
             {
-                DelayedBinding.Add(target, property, x => GetValue(x, targetType));
+                // This is stored locally to avoid allocating closure in the outer scope.
+                var localTargetType = targetType;
+                var localInstance = this;
+                
+                DelayedBinding.Add(target, property, x => localInstance.GetValue(x, localTargetType));
                 return AvaloniaProperty.UnsetValue;
             }
 

src/Markup/Avalonia.Markup.Xaml/Styling/StyleInclude.cs

@@ -60,7 +60,7 @@ namespace Avalonia.Markup.Xaml.Styling
             }
         }
 
-        bool IResourceNode.HasResources => (Loaded as IResourceProvider)?.HasResources ?? false;
+        bool IResourceNode.HasResources => Loaded?.HasResources ?? false;
 
         IReadOnlyList<IStyle> IStyle.Children => _loaded ?? Array.Empty<IStyle>();
 
@@ -86,9 +86,9 @@ namespace Avalonia.Markup.Xaml.Styling
 
         public bool TryGetResource(object key, out object? value)
         {
-            if (!_isLoading && Loaded is IResourceProvider p)
+            if (!_isLoading)
             {
-                return p.TryGetResource(key, out value);
+                return Loaded.TryGetResource(key, out value);
             }
 
             value = null;

src/Skia/Avalonia.Skia/TextShaperImpl.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Globalization;
-using Avalonia.Media;
 using Avalonia.Media.TextFormatting;
 using Avalonia.Media.TextFormatting.Unicode;
 using Avalonia.Platform;
@@ -28,7 +27,7 @@ namespace Avalonia.Skia
                 
                 buffer.GuessSegmentProperties();
 
-                buffer.Direction = (bidiLevel & 1) == 0 ? Direction.LeftToRight : Direction.RightToLeft;
+                buffer.Direction = Direction.LeftToRight; //Always shape LeftToRight
 
                 buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);              
 
@@ -36,11 +35,6 @@ namespace Avalonia.Skia
 
                 font.Shape(buffer);
 
-                if (buffer.Direction == Direction.RightToLeft)
-                {
-                    buffer.Reverse();
-                }
-
                 font.GetScale(out var scaleX, out _);
 
                 var textScale = fontRenderingEmSize / scaleX;
@@ -59,7 +53,7 @@ namespace Avalonia.Skia
 
                     var glyphIndex = (ushort)sourceInfo.Codepoint;
 
-                    var glyphCluster = (int)sourceInfo.Cluster;
+                    var glyphCluster = (int)(sourceInfo.Cluster);
 
                     var glyphAdvance = GetGlyphAdvance(glyphPositions, i, textScale);
 

src/Windows/Avalonia.Direct2D1/Media/TextShaperImpl.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Globalization;
-using Avalonia.Media;
 using Avalonia.Media.TextFormatting;
 using Avalonia.Media.TextFormatting.Unicode;
 using Avalonia.Platform;
@@ -11,8 +10,7 @@ using GlyphInfo = HarfBuzzSharp.GlyphInfo;
 
 namespace Avalonia.Direct2D1.Media
 {
-
-internal class TextShaperImpl : ITextShaperImpl
+    internal class TextShaperImpl : ITextShaperImpl
     {
         public ShapedBuffer ShapeText(ReadOnlySlice<char> text, TextShaperOptions options)
         {
@@ -23,25 +21,20 @@ internal class TextShaperImpl : ITextShaperImpl
 
             using (var buffer = new Buffer())
             {
-                buffer.AddUtf16(text.Buffer.Span, text.Start, text.Length);
+                buffer.AddUtf16(text.Buffer.Span, text.BufferOffset, text.Length);
 
                 MergeBreakPair(buffer);
-                
+
                 buffer.GuessSegmentProperties();
 
-                buffer.Direction = (bidiLevel & 1) == 0 ? Direction.LeftToRight : Direction.RightToLeft;
+                buffer.Direction = Direction.LeftToRight; //Always shape LeftToRight
 
-                buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);              
+                buffer.Language = new Language(culture ?? CultureInfo.CurrentCulture);
 
                 var font = ((GlyphTypefaceImpl)typeface.PlatformImpl).Font;
 
                 font.Shape(buffer);
 
-                if (buffer.Direction == Direction.RightToLeft)
-                {
-                    buffer.Reverse();
-                }
-
                 font.GetScale(out var scaleX, out _);
 
                 var textScale = fontRenderingEmSize / scaleX;
@@ -60,13 +53,13 @@ internal class TextShaperImpl : ITextShaperImpl
 
                     var glyphIndex = (ushort)sourceInfo.Codepoint;
 
-                    var glyphCluster = (int)sourceInfo.Cluster;
+                    var glyphCluster = (int)(sourceInfo.Cluster);
 
                     var glyphAdvance = GetGlyphAdvance(glyphPositions, i, textScale);
 
                     var glyphOffset = GetGlyphOffset(glyphPositions, i, textScale);
 
-                    if (glyphIndex == 0 && text[glyphCluster] == '\t')
+                    if (glyphIndex == 0 && text.Buffer.Span[glyphCluster] == '\t')
                     {
                         glyphIndex = typeface.GetGlyph(' ');
 
@@ -75,9 +68,7 @@ internal class TextShaperImpl : ITextShaperImpl
                             4 * typeface.GetGlyphAdvance(glyphIndex) * textScale;
                     }
 
-                    var targetInfo =
-                        new Avalonia.Media.TextFormatting.GlyphInfo(glyphIndex, glyphCluster, glyphAdvance,
-                            glyphOffset);
+                    var targetInfo = new Avalonia.Media.TextFormatting.GlyphInfo(glyphIndex, glyphCluster, glyphAdvance, glyphOffset);
 
                     shapedBuffer[i] = targetInfo;
                 }
@@ -91,7 +82,7 @@ internal class TextShaperImpl : ITextShaperImpl
             var length = buffer.Length;
 
             var glyphInfos = buffer.GetGlyphInfoSpan();
-            
+
             var second = glyphInfos[length - 1];
 
             if (!new Codepoint((int)second.Codepoint).IsBreakChar)
@@ -102,7 +93,7 @@ internal class TextShaperImpl : ITextShaperImpl
             if (length > 1 && glyphInfos[length - 2].Codepoint == '\r' && second.Codepoint == '\n')
             {
                 var first = glyphInfos[length - 2];
-                
+
                 first.Codepoint = '\u200C';
                 second.Codepoint = '\u200C';
                 second.Cluster = first.Cluster;
@@ -113,7 +104,7 @@ internal class TextShaperImpl : ITextShaperImpl
                     {
                         *p = first;
                     }
-                
+
                     fixed (GlyphInfo* p = &glyphInfos[length - 1])
                     {
                         *p = second;
@@ -148,7 +139,7 @@ internal class TextShaperImpl : ITextShaperImpl
         private static double GetGlyphAdvance(ReadOnlySpan<GlyphPosition> glyphPositions, int index, double textScale)
         {
             // Depends on direction of layout
-            // advanceBuffer[index] = buffer.GlyphPositions[index].YAdvance * textScale;
+            // glyphPositions[index].YAdvance * textScale;
             return glyphPositions[index].XAdvance * textScale;
         }
     }

src/Windows/Avalonia.Win32/Interop/UnmanagedMethods.cs

@@ -914,9 +914,9 @@ namespace Avalonia.Win32.Interop
         [DllImport("user32.dll")]
         public static extern bool EnumDisplayMonitors(IntPtr hdc, IntPtr lprcClip,
                                                       MonitorEnumDelegate lpfnEnum, IntPtr dwData);
-        
+
         public delegate bool MonitorEnumDelegate(IntPtr hMonitor, IntPtr hdcMonitor, ref Rect lprcMonitor, IntPtr dwData);
-        
+
         [DllImport("user32.dll", SetLastError = true)]
         public static extern IntPtr GetDC(IntPtr hWnd);
 
@@ -1007,7 +1007,7 @@ namespace Avalonia.Win32.Interop
 
         public static uint GetWindowLong(IntPtr hWnd, int nIndex)
         {
-            if(IntPtr.Size == 4)
+            if (IntPtr.Size == 4)
             {
                 return GetWindowLong32b(hWnd, nIndex);
             }
@@ -1034,7 +1034,7 @@ namespace Avalonia.Win32.Interop
                 return (uint)SetWindowLong64b(hWnd, nIndex, new IntPtr((uint)value)).ToInt32();
             }
         }
-        
+
         public static IntPtr SetWindowLongPtr(IntPtr hWnd, int nIndex, IntPtr handle)
         {
             if (IntPtr.Size == 4)
@@ -1068,14 +1068,14 @@ namespace Avalonia.Win32.Interop
 
         [DllImport("user32.dll")]
         public static extern bool InvalidateRect(IntPtr hWnd, RECT* lpRect, bool bErase);
-        
-        
+
+
         [DllImport("user32.dll")]
         public static extern bool ValidateRect(IntPtr hWnd, IntPtr lpRect);
 
         [DllImport("user32.dll")]
         public static extern bool IsWindow(IntPtr hWnd);
-        
+
         [DllImport("user32.dll")]
         public static extern bool IsWindowEnabled(IntPtr hWnd);
 
@@ -1102,22 +1102,25 @@ namespace Avalonia.Win32.Interop
 
         [DllImport("user32")]
         public static extern IntPtr GetMessageExtraInfo();
-        
+
         [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode, EntryPoint = "RegisterClassExW")]
         public static extern ushort RegisterClassEx(ref WNDCLASSEX lpwcx);
 
         [DllImport("user32.dll")]
         public static extern void RegisterTouchWindow(IntPtr hWnd, int flags);
-        
+
         [DllImport("user32.dll")]
         public static extern bool ReleaseCapture();
 
+        [DllImport("user32.dll", SetLastError = true)]
+        public static extern uint RegisterWindowMessage(string lpString);
+
         [DllImport("user32.dll")]
         public static extern bool ScreenToClient(IntPtr hWnd, ref POINT lpPoint);
 
         [DllImport("user32.dll", SetLastError = true)]
         public static extern IntPtr GetActiveWindow();
-        
+
         [DllImport("user32.dll", SetLastError = true)]
         public static extern IntPtr SetActiveWindow(IntPtr hWnd);
 
@@ -1304,7 +1307,7 @@ namespace Avalonia.Win32.Interop
 
         [DllImport("kernel32.dll", SetLastError = true)]
         public static extern IntPtr LoadLibrary(string fileName);
-        
+
         [DllImport("kernel32.dll", SetLastError = true)]
         public static extern IntPtr LoadLibraryEx(string fileName, IntPtr hFile, int flags);
 
@@ -1348,7 +1351,7 @@ namespace Avalonia.Win32.Interop
 
         [DllImport("user32.dll")]
         public static extern IntPtr MonitorFromWindow(IntPtr hwnd, MONITOR dwFlags);
-        
+
         [DllImport("user32", EntryPoint = "GetMonitorInfoW", ExactSpelling = true, CharSet = CharSet.Unicode)]
         [return: MarshalAs(UnmanagedType.Bool)]
         public static extern bool GetMonitorInfo([In] IntPtr hMonitor, ref MONITORINFO lpmi);
@@ -1356,14 +1359,14 @@ namespace Avalonia.Win32.Interop
         [DllImport("user32")]
         public static extern unsafe bool GetTouchInputInfo(
             IntPtr hTouchInput,
-            uint        cInputs,
+            uint cInputs,
             TOUCHINPUT* pInputs,
-            int         cbSize
+            int cbSize
         );
-        
+
         [DllImport("user32")]
         public static extern bool CloseTouchInputHandle(IntPtr hTouchInput);
-        
+
         [return: MarshalAs(UnmanagedType.Bool)]
         [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode, EntryPoint = "PostMessageW")]
         public static extern bool PostMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);
@@ -1372,7 +1375,7 @@ namespace Avalonia.Win32.Interop
         public static extern int SetDIBitsToDevice(IntPtr hdc, int XDest, int YDest, uint
                 dwWidth, uint dwHeight, int XSrc, int YSrc, uint uStartScan, uint cScanLines,
             IntPtr lpvBits, [In] ref BITMAPINFOHEADER lpbmi, uint fuColorUse);
-        
+
         [DllImport("kernel32.dll", SetLastError = true)]
         [return: MarshalAs(UnmanagedType.Bool)]
         public static extern bool CloseHandle(IntPtr hObject);
@@ -1387,27 +1390,27 @@ namespace Avalonia.Win32.Interop
 
         [DllImport("gdi32.dll")]
         public static extern int ChoosePixelFormat(IntPtr hdc, ref PixelFormatDescriptor pfd);
-        
+
         [DllImport("gdi32.dll")]
         public static extern int DescribePixelFormat(IntPtr hdc, ref PixelFormatDescriptor pfd);
 
         [DllImport("gdi32.dll")]
         public static extern int SetPixelFormat(IntPtr hdc, int iPixelFormat, ref PixelFormatDescriptor pfd);
-        
-        
+
+
         [DllImport("gdi32.dll")]
         public static extern int DescribePixelFormat(IntPtr hdc, int iPixelFormat, int bytes, ref PixelFormatDescriptor pfd);
-        
+
         [DllImport("gdi32.dll")]
         public static extern bool SwapBuffers(IntPtr hdc);
 
         [DllImport("opengl32.dll")]
         public static extern IntPtr wglCreateContext(IntPtr hdc);
-        
+
         [DllImport("opengl32.dll")]
         public static extern bool wglDeleteContext(IntPtr context);
 
-        
+
         [DllImport("opengl32.dll")]
         public static extern bool wglMakeCurrent(IntPtr hdc, IntPtr context);
 
@@ -1428,9 +1431,9 @@ namespace Avalonia.Win32.Interop
             uint dwMaximumSizeLow,
             string lpName);
 
-        [DllImport("msvcrt.dll", EntryPoint="memcpy", SetLastError = false, CallingConvention=CallingConvention.Cdecl)]
-        public static extern IntPtr CopyMemory(IntPtr dest, IntPtr src, UIntPtr count); 
-        
+        [DllImport("msvcrt.dll", EntryPoint = "memcpy", SetLastError = false, CallingConvention = CallingConvention.Cdecl)]
+        public static extern IntPtr CopyMemory(IntPtr dest, IntPtr src, UIntPtr count);
+
         [DllImport("ole32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
         public static extern HRESULT RegisterDragDrop(IntPtr hwnd, IntPtr target);
 
@@ -1472,10 +1475,10 @@ namespace Avalonia.Win32.Interop
 
         [DllImport("dwmapi.dll")]
         public static extern void DwmFlush();
-        
+
         [DllImport("dwmapi.dll")]
         public static extern bool DwmDefWindowProc(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam, ref IntPtr plResult);
-        
+
         [DllImport("dwmapi.dll")]
         public static extern void DwmEnableBlurBehindWindow(IntPtr hwnd, ref DWM_BLURBEHIND blurBehind);
         
@@ -1542,8 +1545,8 @@ namespace Avalonia.Win32.Interop
                 throw new Exception("RtlGetVersion failed!");
             }
         }
-        
-        [DllImport("kernel32", EntryPoint="WaitForMultipleObjectsEx", SetLastError = true, CharSet = CharSet.Auto)]
+
+        [DllImport("kernel32", EntryPoint = "WaitForMultipleObjectsEx", SetLastError = true, CharSet = CharSet.Auto)]
         private static extern int IntWaitForMultipleObjectsEx(int nCount, IntPtr[] pHandles, bool bWaitAll, int dwMilliseconds, bool bAlertable);
 
         public const int WAIT_FAILED = unchecked((int)0xFFFFFFFF);
@@ -1551,7 +1554,7 @@ namespace Avalonia.Win32.Interop
         internal static int WaitForMultipleObjectsEx(int nCount, IntPtr[] pHandles, bool bWaitAll, int dwMilliseconds, bool bAlertable)
         {
             int result = IntWaitForMultipleObjectsEx(nCount, pHandles, bWaitAll, dwMilliseconds, bAlertable);
-            if(result ==  WAIT_FAILED)
+            if (result == WAIT_FAILED)
             {
                 throw new Win32Exception();
             }
@@ -1699,7 +1702,7 @@ namespace Avalonia.Win32.Interop
             DrawLeftBorder = 0x20,
             DrawTopBorder = 0x40,
             DrawRightBorder = 0x80,
-            DrawBottomBorder = 0x100,            
+            DrawBottomBorder = 0x100,
         }
 
         [StructLayout(LayoutKind.Sequential)]
@@ -1767,9 +1770,9 @@ namespace Avalonia.Win32.Interop
             MDT_ANGULAR_DPI = 1,
             MDT_RAW_DPI = 2,
             MDT_DEFAULT = MDT_EFFECTIVE_DPI
-        } 
+        }
 
-        public enum ClipboardFormat 
+        public enum ClipboardFormat
         {
             /// <summary>
             /// Text format. Each line ends with a carriage return/linefeed (CR-LF) combination. A null character signals the end of the data. Use this format for ANSI text.
@@ -1820,7 +1823,7 @@ namespace Avalonia.Win32.Interop
             public int X;
             public int Y;
         }
-        
+
         public struct SIZE
         {
             public int X;
@@ -2021,7 +2024,7 @@ namespace Avalonia.Win32.Interop
             OFN_NOREADONLYRETURN = 0x00008000,
             OFN_OVERWRITEPROMPT = 0x00000002
         }
-        
+
         public enum HRESULT : uint
         {
             S_FALSE = 0x0001,

src/Windows/Avalonia.Win32/TrayIconImpl.cs

@@ -24,6 +24,7 @@ namespace Avalonia.Win32
         private readonly Win32NativeToManagedMenuExporter _exporter;
         private static readonly Dictionary<int, TrayIconImpl> s_trayIcons = new Dictionary<int, TrayIconImpl>();
         private bool _disposedValue;
+        private static readonly uint WM_TASKBARCREATED = UnmanagedMethods.RegisterWindowMessage("TaskbarCreated");
 
         public TrayIconImpl()
         {
@@ -44,6 +45,18 @@ namespace Avalonia.Win32
             {
                 s_trayIcons[wParam.ToInt32()].WndProc(hWnd, msg, wParam, lParam);
             }
+
+            if (msg == WM_TASKBARCREATED)
+            {
+                foreach (var tray in s_trayIcons.Values)
+                {
+                    if (tray._iconAdded)
+                    {
+                        tray.UpdateIcon(true);
+                        tray.UpdateIcon();
+                    }
+                }
+            }
         }
 
         public void SetIcon(IWindowIconImpl? icon)
@@ -145,7 +158,7 @@ namespace Avalonia.Win32
         private enum CustomWindowsMessage : uint
         {
             WM_TRAYICON = WindowsMessage.WM_APP + 1024,
-            WM_TRAYMOUSE = WindowsMessage.WM_USER + 1024
+            WM_TRAYMOUSE = WindowsMessage.WM_USER + 1024,
         }
 
         private class TrayIconMenuFlyoutPresenter : MenuFlyoutPresenter, IStyleable

tests/Avalonia.Controls.UnitTests/Primitives/SelectingItemsControlTests.cs

@@ -6,6 +6,7 @@ using System.Collections.Specialized;
 using System.ComponentModel;
 using System.Linq;
 using System.Reactive.Disposables;
+using System.Threading.Tasks;
 using Avalonia.Collections;
 using Avalonia.Controls.Presenters;
 using Avalonia.Controls.Primitives;
@@ -1614,6 +1615,50 @@ namespace Avalonia.Controls.UnitTests.Primitives
             target.MoveSelection(NavigationDirection.Next, true);
         }
 
+        [Fact(Timeout = 2000)]
+        public async Task MoveSelection_Does_Not_Hang_With_No_Focusable_Controls_And_Moving_Selection_To_The_First_Item()
+        {
+            var target = new TestSelector
+            {
+                Template = Template(),
+                Items = new[]
+                {
+                    new ListBoxItem { Focusable = false },
+                    new ListBoxItem(),
+                }
+            };
+
+            target.Measure(new Size(100, 100));
+            target.Arrange(new Rect(0, 0, 100, 100));
+
+            // Timeout in xUnit doesen't work with synchronous methods so we need to apply hack below.
+            // https://github.com/xunit/xunit/issues/2222
+            await Task.Run(() => target.MoveSelection(NavigationDirection.First, true));
+            Assert.Equal(-1, target.SelectedIndex);
+        }
+
+        [Fact(Timeout = 2000)]
+        public async Task MoveSelection_Does_Not_Hang_With_No_Focusable_Controls_And_Moving_Selection_To_The_Last_Item()
+        {
+            var target = new TestSelector
+            {
+                Template = Template(),
+                Items = new[]
+                {
+                    new ListBoxItem(),
+                    new ListBoxItem { Focusable = false },
+                }
+            };
+
+            target.Measure(new Size(100, 100));
+            target.Arrange(new Rect(0, 0, 100, 100));
+
+            // Timeout in xUnit doesen't work with synchronous methods so we need to apply hack below.
+            // https://github.com/xunit/xunit/issues/2222
+            await Task.Run(() => target.MoveSelection(NavigationDirection.Last, true));
+            Assert.Equal(-1, target.SelectedIndex);
+        }
+
         [Fact]
         public void MoveSelection_Does_Select_Disabled_Controls()
         {

tests/Avalonia.RenderTests/Media/TextFormatting/TextLayoutTests.cs

@@ -1,11 +1,8 @@
 using Avalonia.Media;
-using Avalonia.Platform;
 using System;
-using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
 using System.Runtime.InteropServices;
-using System.Text;
 using System.Threading.Tasks;
 using Avalonia.Controls;
 using Avalonia.Media.TextFormatting;

tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextLineTests.cs

@@ -70,12 +70,12 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                 }
             }
         }
-        
+
         [Fact]
         public void Should_Get_Next_Caret_CharacterHit_Bidi()
         {
             const string text = "אבג 1 ABC";
-            
+
             using (Start())
             {
                 var defaultProperties = new GenericTextRunProperties(Typeface.Default);
@@ -90,7 +90,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 var clusters = new List<int>();
 
-                foreach (var textRun in textLine.TextRuns.OrderBy(x=> x.Text.Start))
+                foreach (var textRun in textLine.TextRuns.OrderBy(x => x.Text.Start))
                 {
                     var shapedRun = (ShapedTextCharacters)textRun;
 
@@ -98,7 +98,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                         shapedRun.ShapedBuffer.GlyphClusters.Reverse() :
                         shapedRun.ShapedBuffer.GlyphClusters);
                 }
-                
+
                 var nextCharacterHit = new CharacterHit(0, clusters[1] - clusters[0]);
 
                 foreach (var cluster in clusters)
@@ -122,7 +122,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
         public void Should_Get_Previous_Caret_CharacterHit_Bidi()
         {
             const string text = "אבג 1 ABC";
-            
+
             using (Start())
             {
                 var defaultProperties = new GenericTextRunProperties(Typeface.Default);
@@ -137,7 +137,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 var clusters = new List<int>();
 
-                foreach (var textRun in textLine.TextRuns.OrderBy(x=> x.Text.Start))
+                foreach (var textRun in textLine.TextRuns.OrderBy(x => x.Text.Start))
                 {
                     var shapedRun = (ShapedTextCharacters)textRun;
 
@@ -147,13 +147,13 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                 }
 
                 clusters.Reverse();
-                
+
                 var nextCharacterHit = new CharacterHit(text.Length - 1);
 
                 foreach (var cluster in clusters)
                 {
                     var currentCaretIndex = nextCharacterHit.FirstCharacterIndex + nextCharacterHit.TrailingLength;
-                    
+
                     Assert.Equal(cluster, currentCaretIndex);
 
                     nextCharacterHit = textLine.GetPreviousCaretCharacterHit(nextCharacterHit);
@@ -168,7 +168,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                 Assert.Equal(lastCharacterHit.TrailingLength, nextCharacterHit.TrailingLength);
             }
         }
-        
+
         [InlineData("𐐷𐐷𐐷𐐷𐐷")]
         [InlineData("01234567🎉\n")]
         [InlineData("𐐷1234")]
@@ -324,7 +324,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                     }
                 }
 
-                Assert.Equal(currentDistance,textLine.GetDistanceFromCharacterHit(new CharacterHit(s_multiLineText.Length)));
+                Assert.Equal(currentDistance, textLine.GetDistanceFromCharacterHit(new CharacterHit(s_multiLineText.Length)));
             }
         }
 
@@ -371,7 +371,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                 yield return CreateData("01234 01234", 58, TextTrimming.WordEllipsis, "01234\u2026");
                 yield return CreateData("01234", 9, TextTrimming.CharacterEllipsis, "\u2026");
                 yield return CreateData("01234", 2, TextTrimming.CharacterEllipsis, "");
-                
+
                 object[] CreateData(string text, double width, TextTrimming mode, string expected)
                 {
                     return new object[]
@@ -424,7 +424,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
             {
                 var defaultProperties = new GenericTextRunProperties(Typeface.Default);
                 var textSource = new DrawableRunTextSource();
-                
+
                 var formatter = new TextFormatterImpl();
 
                 var textLine =
@@ -471,7 +471,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 Assert.Equal(4, textLine.TextRuns.Count);
 
-                var currentHit = textLine.GetPreviousCaretCharacterHit(new CharacterHit(3,1));
+                var currentHit = textLine.GetPreviousCaretCharacterHit(new CharacterHit(3, 1));
 
                 Assert.Equal(3, currentHit.FirstCharacterIndex);
                 Assert.Equal(0, currentHit.TrailingLength);
@@ -552,11 +552,11 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                 switch (textSourceIndex)
                 {
                     case 0:
-                        return new CustomDrawableRun();                     
+                        return new CustomDrawableRun();
                     case 1:
                         return new TextCharacters(new ReadOnlySlice<char>(Text.AsMemory(), 1, 1, 1), new GenericTextRunProperties(Typeface.Default));
                     case 2:
-                        return new CustomDrawableRun();                      
+                        return new CustomDrawableRun();
                     case 3:
                         return new TextCharacters(new ReadOnlySlice<char>(Text.AsMemory(), 3, 1, 3), new GenericTextRunProperties(Typeface.Default));
                     default:
@@ -564,14 +564,14 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                 }
             }
         }
-        
+
         private class CustomDrawableRun : DrawableTextRun
         {
             public override Size Size => new(14, 14);
             public override double Baseline => 14;
             public override void Draw(DrawingContext drawingContext, Point origin)
             {
-               
+
             }
         }
 
@@ -587,29 +587,29 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
             var shapedTextRuns = textLine.TextRuns.Cast<ShapedTextCharacters>().ToList();
 
             var lastCluster = -1;
-            
+
             foreach (var textRun in shapedTextRuns)
             {
                 var shapedBuffer = textRun.ShapedBuffer;
 
                 var currentClusters = shapedBuffer.GlyphClusters.ToList();
 
-                foreach (var currentCluster in currentClusters) 
+                foreach (var currentCluster in currentClusters)
                 {
                     if (lastCluster == currentCluster)
                     {
                         continue;
                     }
-                    
+
                     glyphClusters.Add(currentCluster);
 
                     lastCluster = currentCluster;
                 }
             }
-            
+
             return glyphClusters;
         }
-        
+
         private static List<Rect> BuildRects(TextLine textLine)
         {
             var rects = new List<Rect>();
@@ -624,11 +624,11 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
             foreach (var textRun in shapedTextRuns)
             {
                 var shapedBuffer = textRun.ShapedBuffer;
-            
+
                 for (var index = 0; index < shapedBuffer.GlyphAdvances.Count; index++)
                 {
                     var currentCluster = shapedBuffer.GlyphClusters[index];
-                
+
                     var advance = shapedBuffer.GlyphAdvances[index];
 
                     if (lastCluster != currentCluster)
@@ -642,10 +642,10 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                         rects.Remove(rect);
 
                         rect = rect.WithWidth(rect.Width + advance);
-                    
+
                         rects.Add(rect);
                     }
-                    
+
                     currentX += advance;
 
                     lastCluster = currentCluster;
@@ -655,8 +655,65 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
             return rects;
         }
 
+
+        [Fact]
+        public void Should_Get_TextBounds_Mixed()
+        {
+            using (Start())
+            {
+                var defaultProperties = new GenericTextRunProperties(Typeface.Default);
+                var text = "0123".AsMemory();
+                var shaperOption = new TextShaperOptions(Typeface.Default.GlyphTypeface, 10, 0, CultureInfo.CurrentCulture);
+
+                var firstRun = new ShapedTextCharacters(TextShaper.Current.ShapeText(new ReadOnlySlice<char>(text, 1, text.Length), shaperOption), defaultProperties);
+
+                var textRuns = new List<TextRun>
+                {
+                    new CustomDrawableRun(),
+                    firstRun,
+                    new CustomDrawableRun(),
+                    new ShapedTextCharacters(TextShaper.Current.ShapeText(new ReadOnlySlice<char>(text, text.Length + 2, text.Length), shaperOption), defaultProperties),
+                    new CustomDrawableRun(),
+                    new ShapedTextCharacters(TextShaper.Current.ShapeText(new ReadOnlySlice<char>(text, text.Length * 2 + 3, text.Length), shaperOption), defaultProperties)
+                };
+
+                var textSource = new FixedRunsTextSource(textRuns);
+
+                var formatter = new TextFormatterImpl();
+
+                var textLine =
+                    formatter.FormatLine(textSource, 0, double.PositiveInfinity,
+                        new GenericTextParagraphProperties(defaultProperties));
+
+                var textBounds = textLine.GetTextBounds(0, text.Length * 3 + 3);
+
+                Assert.Equal(1, textBounds.Count);
+                Assert.Equal(textLine.WidthIncludingTrailingWhitespace, textBounds.Sum(x => x.Rectangle.Width));
+
+                textBounds = textLine.GetTextBounds(0, 1);
+
+                Assert.Equal(1, textBounds.Count);
+                Assert.Equal(14, textBounds[0].Rectangle.Width);
+
+                textBounds = textLine.GetTextBounds(0, firstRun.Text.Length + 1);
+
+                Assert.Equal(1, textBounds.Count);
+                Assert.Equal(firstRun.Size.Width + 14, textBounds[0].Rectangle.Width);
+
+                textBounds = textLine.GetTextBounds(1, firstRun.Text.Length);
+
+                Assert.Equal(1, textBounds.Count);
+                Assert.Equal(firstRun.Size.Width, textBounds[0].Rectangle.Width);
+
+                textBounds = textLine.GetTextBounds(1, firstRun.Text.Length + 1);
+
+                Assert.Equal(1, textBounds.Count);
+                Assert.Equal(firstRun.Size.Width + 14, textBounds[0].Rectangle.Width);
+            }
+        }
+
         [Fact]
-        public void Should_Get_TextBounds()
+        public void Should_Get_TextBounds_BiDi()
         {
             using (Start())
             {
@@ -673,7 +730,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                     new ShapedTextCharacters(TextShaper.Current.ShapeText(new ReadOnlySlice<char>(text, text.Length * 3, text.Length), ltrOptions), defaultProperties)
                 };
 
-             
+
                 var textSource = new FixedRunsTextSource(textRuns);
 
                 var formatter = new TextFormatterImpl();
@@ -700,12 +757,16 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
             public TextRun? GetTextRun(int textSourceIndex)
             {
+                var currentPosition = 0;
+
                 foreach (var textRun in _textRuns)
                 {
-                    if(textRun.Text.Start == textSourceIndex)
+                    if (currentPosition == textSourceIndex)
                     {
                         return textRun;
                     }
+
+                    currentPosition += textRun.TextSourceLength;
                 }
 
                 return null;