Wayland: handle (0,0) surface size (#21863)

src/Avalonia.Wayland/Server/Persistent/WSurface.cs

@@ -591,6 +591,12 @@ class WXdgShellSurface : WSurface, IWXdgShellSurface
             surfaceHeight = (bufferPixelSize.Height + intScale - 1) / intScale;
         }
 
+        if (surfaceWidth <= 0 || surfaceHeight <= 0)
+        {
+            LastWindowGeometry = null;
+            return;
+        }
+
         var left = Math.Clamp((int)shadowExtents.Left, 0, surfaceWidth - 1);
         var top = Math.Clamp((int)shadowExtents.Top, 0, surfaceHeight - 1);
         var right = Math.Clamp(
@@ -1101,4 +1107,4 @@ class WXdgPopup : WXdgShellSurface, IWXdgPopup
         _pendingBatch = new();
         base.OnDisconnected();
     }
-}
+}

src/Avalonia.Wayland/Server/Transient/Rendering/WaylandEglDmaBufSurface.cs

@@ -55,7 +55,10 @@ internal class WaylandEglDmaBufSurface : EglGlPlatformImageSurfaceBase, IPlatfor
             if (!_parent._surface.State.IsReady)
                 throw new RenderTargetNotReadyException();
 
-            EnsureSwapchain(sceneInfo.Size);
+            var size = sceneInfo.Size;
+            size = new PixelSize(Math.Max(1, size.Width), Math.Max(1, size.Height));
+
+            EnsureSwapchain(size);
 
             // Select least recently used free slot
             BufferSlot? freeSlot = null;
@@ -70,7 +73,7 @@ internal class WaylandEglDmaBufSurface : EglGlPlatformImageSurfaceBase, IPlatfor
 
             var capturedSlot = freeSlot;
             capturedSlot.LastUsedFrame = ++_frameCounter;
-            return BeginDraw(capturedSlot.EglImage!.Handle, sceneInfo.Size, sceneInfo.Scaling, () =>
+            return BeginDraw(capturedSlot.EglImage!.Handle, size, sceneInfo.Scaling, () =>
             {
                 // Stage per-frame state (frame callback + ack_configure +
                 // geometry + viewport/scale + min/max) into the next
@@ -79,7 +82,7 @@ internal class WaylandEglDmaBufSurface : EglGlPlatformImageSurfaceBase, IPlatfor
                 // issues the commit itself.
                 _parent._surface.OnBeforeNewBufferAttached(sceneInfo);
                 _parent._surface.WlSurface!.Attach(capturedSlot.WlBuffer!, 0, 0);
-                _parent._surface.WlSurface.DamageBuffer(0, 0, sceneInfo.Size.Width, sceneInfo.Size.Height);
+                _parent._surface.WlSurface.DamageBuffer(0, 0, size.Width, size.Height);
                 capturedSlot.Busy = true;
                 _parent._surface.WlSurface.Commit();
             });

src/Avalonia.Wayland/Server/Transient/Rendering/WaylandEglWsiSurface.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Diagnostics;
 using Avalonia.OpenGL;
 using Avalonia.OpenGL.Egl;
 using Avalonia.OpenGL.Surfaces;
@@ -64,7 +65,10 @@ internal sealed class WaylandEglWsiSurface : EglGlPlatformSurfaceBase, IPlatform
             if (!_surface.State.IsReady)
                 throw new RenderTargetNotReadyException();
 
-            EnsureWindow(sceneInfo.Size);
+            var size = sceneInfo.Size;
+            size = new PixelSize(Math.Max(1, size.Width), Math.Max(1, size.Height));
+
+            EnsureWindow(size);
 
             // OnBeforeNewBufferAttached must run *immediately* before the
             // implicit commit performed by eglSwapBuffers; the base class
@@ -73,7 +77,7 @@ internal sealed class WaylandEglWsiSurface : EglGlPlatformSurfaceBase, IPlatform
             // SwapInterval(0) is set inside beforeSwap (so it runs with our
             // surface current); GTK re-asserts it every frame defensively
             // and we follow suit — some drivers reset it on resize.
-            var session = BeginDraw(_eglSurface!, sceneInfo.Size, sceneInfo.Scaling,
+            var session = BeginDraw(_eglSurface!, size, sceneInfo.Scaling,
                 beforeSwap: () =>
                 {
                     var display = Context.Display;
@@ -86,7 +90,7 @@ internal sealed class WaylandEglWsiSurface : EglGlPlatformSurfaceBase, IPlatform
             if (session.Context.Version.Type == GlProfileType.OpenGL)
             {
                 var gl = session.Context.GlInterface;
-                gl.Viewport(0, 0, sceneInfo.Size.Width, sceneInfo.Size.Height);
+                gl.Viewport(0, 0, size.Width, size.Height);
                 if (gl.IsReadBufferAvailable)
                     gl.ReadBuffer(GL_BACK);
                 if (gl.IsWriteBufferAvailable)
@@ -118,13 +122,15 @@ internal sealed class WaylandEglWsiSurface : EglGlPlatformSurfaceBase, IPlatform
 
         private void EnsureWindow(PixelSize size)
         {
+            Debug.Assert(size.Width > 0 && size.Height > 0);
+
             if (_eglWindow != IntPtr.Zero && _currentSize == size)
                 return;
 
             if (_eglWindow == IntPtr.Zero)
             {
                 _eglWindow = WaylandEglNativeMethods.wl_egl_window_create(
-                    _surface.WlSurface!.Handle, Math.Max(1, size.Width), Math.Max(1, size.Height));
+                    _surface.WlSurface!.Handle, size.Width, size.Height);
                 if (_eglWindow == IntPtr.Zero)
                     throw new OpenGlException("wl_egl_window_create failed");
 
@@ -141,8 +147,7 @@ internal sealed class WaylandEglWsiSurface : EglGlPlatformSurfaceBase, IPlatform
             }
             else
             {
-                WaylandEglNativeMethods.wl_egl_window_resize(_eglWindow,
-                    Math.Max(1, size.Width), Math.Max(1, size.Height), 0, 0);
+                WaylandEglNativeMethods.wl_egl_window_resize(_eglWindow, size.Width, size.Height, 0, 0);
             }
 
             _currentSize = size;

src/Avalonia.Wayland/Server/Transient/Rendering/WaylandFramebuffer.cs

@@ -47,7 +47,9 @@ class WaylandFramebuffer(IWaylandFramebufferSurface surface) : IFramebufferPlatf
                 throw new RenderTargetNotReadyException();
 
             var size = sceneInfo.Size;
-            var bufferLen = sceneInfo.Size.Width * sceneInfo.Size.Height * 4;
+            size = new PixelSize(Math.Max(1, size.Width), Math.Max(1, size.Height));
+
+            var bufferLen = size.Width * size.Height * 4;
             var stride = size.Width * 4;
             
             var fd = memfd_create("avalonia-wayland-framebuffer", MFD_CLOEXEC);