Win2D.UnoCompat

Win2D.UnoCompat is a desktop-first compatibility shim that provides a subset of the Win2D API surface for Uno Platform apps.

It translates Microsoft.Graphics.Canvas drawing and text APIs into SkiaSharp operations so Uno projects can compile and run without the native Win2D package on non-Windows targets.

Current scope:

• 124 public types covering ~89% of the Win2D public API surface (~529 / ~600 members)
• Full drawing session with shapes, geometry, text, layers, transforms, and blend modes
• Bitmap load/save/create/copy with pixel-level access
• Effects pipeline: blur, shadow, color matrix, composite, blend, crop, transform, color management, and custom PixelShaderEffect with HLSL compilation
• Brushes: solid color, image, linear/radial gradient
• Geometry: shape factories, combine, stroke, hit-testing, path builder
• Text: format, layout, cluster metrics, font face
• Controls: CanvasControl, CanvasAnimatedControl
• Image sources: CanvasImageSource, CanvasVirtualImageSource
• Sprite batching, printing, SVG, ink, typography
• Keep public namespaces close to Win2D so existing source code needs fewer changes
• Track parity explicitly and avoid pretending unsupported Win2D APIs are complete

Compatibility

Win2D.UnoCompat includes a dedicated compatibility test suite that links Win2D's official C# test files and runs them against the Uno2D implementation.

Current status: 46 / 46 tests passing across all major API areas:

Area	Tests	Status
CanvasDevice	3	✅
CanvasRenderTarget	3	✅
CanvasBitmap (load/save/pixels)	10	✅
CanvasDrawingSession (DrawImage)	3	✅
Effects (blur, shadow, color matrix, composite, etc.)	5	✅
PixelShaderEffect (HLSL compilation, properties, validation)	15	✅
CanvasCommandList	2	✅
CanvasImageSource	1	✅
CanvasSpriteBatch	1	✅
CanvasAnimatedControl	1	✅
CanvasGeometry	1	✅
CanvasPrintDocument	1	✅

Code Coverage

Metric	Value
Sequence points	83.0%
Branch coverage	56.3%
Excluding auto-generated code	85.9%

Supported Platforms

• Windows 11 (Windows 10 may work but is not a primary target)
• macOS, 3 most recent versions from 2023-2025
• Ubuntu latest LTS (other Linux distributions may work but are not primary targets)

If you are looking for support of a specific platform, business sponsorship is the way to accelerate that work. Please reach out to us at homepage.

Get Started

One NuGet package is available:

• Win2D-compatible drawing and text primitives backed by SkiaSharp.

Default usage

dotnet add package LeXtudio.Win2D.UnoCompat

xmlns:canvas="using:Microsoft.Graphics.Canvas.UI.Xaml"

<canvas:CanvasControl Draw="Canvas_Draw" />

using Microsoft.Graphics.Canvas.UI.Xaml;
using Microsoft.Graphics.Canvas.Text;
using Windows.UI;

private void Canvas_Draw(CanvasControl sender, CanvasDrawEventArgs args)
{
    var ds = args.DrawingSession;
    ds.DrawLine(12, 12, 240, 12, Colors.DeepSkyBlue, 2);
    ds.DrawRectangle(12, 32, 180, 72, Colors.OrangeRed, 1);
    ds.DrawText("Hello from Win2D.UnoCompat", 16, 56, Colors.White, new CanvasTextFormat
    {
        FontFamily = "Segoe UI",
        FontSize = 18
    });
}

Current Status

Stable preview (v0.x.y) releases are available on NuGet.

This package is a compatibility shim that covers ~89% of the Win2D public API surface (~529 / ~600 public members across 124 types). The remaining gaps are in niche areas not yet needed by LeXtudio Uno tools.

TODO Items Before v1.0.0

• Drawing session parity (shapes, geometry, text, layers, transform, blend)
• Bitmap load/save/create/copy with pixel-level access
• Effects pipeline (blur, shadow, color matrix, composite, crop, transform, color management, custom PixelShaderEffect)
• Brushes (solid, image, linear/radial gradient)
• Geometry operations (combine, stroke, hit-test, path builder)
• Controls (CanvasControl, CanvasAnimatedControl)
• Image sources (CanvasImageSource, CanvasVirtualImageSource)
• Sprite batching, printing, SVG, ink, typography
• Win2D official C# test suite: 46/46 passing
• Add visual regression samples
• Publish v1.0.0 stable release

License

Win2D.UnoCompat is licensed under the MIT License. See LICENSE for details.

Copyright

Copyright (c) 2026 LeXtudio, Inc. All rights reserved.