Merge branch 'master' into fixes/dc-render-layers

src/Gtk/Avalonia.Gtk3/IDeferredRenderOperation.cs

@@ -4,6 +4,6 @@ namespace Avalonia.Gtk3
 {
     public interface IDeferredRenderOperation : IDisposable
     {
-        void RenderNow();
+        void RenderNow(IntPtr? ctx);
     }
 }

src/Gtk/Avalonia.Gtk3/ImageSurfaceFramebuffer.cs

@@ -88,10 +88,10 @@ namespace Avalonia.Gtk3
             private readonly int _width;
             private readonly int _height;
 
-            public RenderOp(GtkWidget widget, ManagedCairoSurface _surface, double factor, int width, int height)
+            public RenderOp(GtkWidget widget, ManagedCairoSurface surface, double factor, int width, int height)
             {
                 _widget = widget;
-                this._surface = _surface;
+                _surface = surface ?? throw new ArgumentNullException();
                 _factor = factor;
                 _width = width;
                 _height = height;
@@ -103,9 +103,12 @@ namespace Avalonia.Gtk3
                 _surface = null;
             }
 
-            public void RenderNow()
+            public void RenderNow(IntPtr? ctx)
             {
-                DrawToWidget(_widget, _surface.Surface, _width, _height, _factor);
+                if(ctx.HasValue)
+                    Draw(ctx.Value, _surface.Surface, _factor);
+                else
+                    DrawToWidget(_widget, _surface.Surface, _width, _height, _factor);
             }
         }
         

src/Gtk/Avalonia.Gtk3/WindowBaseImpl.cs

@@ -286,7 +286,7 @@ namespace Avalonia.Gtk3
             }
             if (op != null)
             {
-                op?.RenderNow();
+                op?.RenderNow(null);
                 op?.Dispose();
             }
         }

src/Shared/PlatformSupport/StandardRuntimePlatform.cs

@@ -76,6 +76,7 @@ namespace Avalonia.Shared.PlatformSupport
                     GC.RemoveMemoryPressure(Size);
                     IsDisposed = true;
                     Address = IntPtr.Zero;
+                    Size = 0;
                 }
             }
 

src/Skia/Avalonia.Skia/BitmapImpl.cs

@@ -33,16 +33,22 @@ namespace Avalonia.Skia
             PixelWidth = width;
             _dpi = dpi;
             var colorType = fmt?.ToSkColorType() ?? SKImageInfo.PlatformColorType;
-            var runtime = AvaloniaLocator.Current?.GetService<IRuntimePlatform>()?.GetRuntimeInfo();
+            var runtimePlatform = AvaloniaLocator.Current?.GetService<IRuntimePlatform>();
+            var runtime = runtimePlatform?.GetRuntimeInfo();
             if (runtime?.IsDesktop == true && runtime?.OperatingSystem == OperatingSystemType.Linux)
                 colorType = SKColorType.Bgra8888;
-            
-            Bitmap = new SKBitmap();
-            var nfo = new SKImageInfo(width, height, colorType, SKAlphaType.Premul);
-            var plat = AvaloniaLocator.Current.GetService<IRuntimePlatform>();
-            var blob = plat.AllocBlob(nfo.BytesSize);
-            Bitmap.InstallPixels(nfo, blob.Address, nfo.RowBytes, null, ReleaseDelegate, blob);
-            Bitmap = new SKBitmap(width, height, colorType, SKAlphaType.Premul);
+
+            if (runtimePlatform != null)
+            {
+                Bitmap = new SKBitmap();
+                var nfo = new SKImageInfo(width, height, colorType, SKAlphaType.Premul);
+                var plat = AvaloniaLocator.Current.GetService<IRuntimePlatform>();
+                var blob = plat.AllocBlob(nfo.BytesSize);
+                Bitmap.InstallPixels(nfo, blob.Address, nfo.RowBytes, null, ReleaseDelegate, blob);
+                
+            }
+            else 
+                Bitmap =  new SKBitmap(width, height, colorType, SKAlphaType.Premul);
             Bitmap.Erase(SKColor.Empty);
         }
 

src/Skia/Avalonia.Skia/DrawingContextImpl.cs

@@ -112,6 +112,7 @@ namespace Avalonia.Skia
             public readonly SKPaint Paint;
 
             private IDisposable _disposable1;
+            private IDisposable _disposable2;
 
             public IDisposable ApplyTo(SKPaint paint)
             {
@@ -127,6 +128,8 @@ namespace Avalonia.Skia
             {
                 if (_disposable1 == null)
                     _disposable1 = disposable;
+                else if (_disposable2 == null)
+                    _disposable2 = disposable;
                 else
                     throw new InvalidOperationException();
             }
@@ -135,12 +138,14 @@ namespace Avalonia.Skia
             {
                 Paint = paint;
                 _disposable1 = null;
+                _disposable2 = null;
             }
 
             public void Dispose()
             {
                 Paint?.Dispose();
                 _disposable1?.Dispose();
+                _disposable2?.Dispose();
             }
         }
 
@@ -221,8 +226,8 @@ namespace Avalonia.Skia
                             _visualBrushRenderer.RenderVisualBrush(ctx, visualBrush);
                         }
 
-                        rv.AddDisposable(tileBrushImage);
                         tileBrushImage = intermediate;
+                        rv.AddDisposable(tileBrushImage);
                     }
                 }
                 else