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Comment by bratsche | Hacker News Reader

There is also a .NET binding for Windows and Xamarin: https://www.nuget.org/packages/SkiaSharp/

We do lots of markup/drawing/overlay apps using Xamarin and SkiaSharp (SKCanvas/SKCanvasView/SKBitmap).

Skia is a great library. Pretty fast across UWP, Android, iOS and nice to have a common cross platform one that works well across most platforms (UWP, Win, Mac, iOS, Android).

UWP combined with Windows Ink (InkCanvas) is fun stuff.

Has anyone used this? Are there any examples?

We used it for our image rendering server, and it worked really great at the beginning. The library is fast, and the API was easy to use, and it worked on Azure App Service without issues.

We eventually abandoned Skia though because it only operates with premultiplied alpha. Works ok if you render on opaque surfaces, but we needed to generate transparent PNGs, and in the allotted timeframe couldn't resolve some rendering differences.

I’m converting a large desktop (CAD) app from GDI+ to SkiaSharp at the moment. Really liking the Api and the quality of the C# wrapper. Also maps very well to GDI concepts so a conversion is fairly painless.

Cool. Are you able to share any more details? I'm guessing this isn't a standard WinForms app. What advantages does moving away from GDI+ give you?

It’s a winforms app, and there isn’t much nonstandard about it other than that large performance sensitive drawing apps are perhaps quite nonstandard to begin with. We want to handle some large cad scenarios in it (e.g smooth pan/zoom in drawings with 500k lines), it’s not the default use case, but it happens. The main advandtage over gdi+ ) is better support for retained mode drawing (record/playback style drawing), more efficient automatic culling, etc.

Why are you converting to SkiaSharp, if I may ask? Is it for performance or multiplatform reasons?

See my answer on the other msg

Cool, how does it compare to Win2D?

It’s just a lot less ”different”. Performance is pretty similar across all frameworks, and is much more dependent on call patterns than anything else.

There are some examples in the source tree here: https://github.com/mono/SkiaSharp/tree/master/samples

The rather awesome, cross-platform, Microcharts (https://github.com/aloisdeniel/Microcharts) is built on top of SkiaSharp.

It's used as one of the backends for Avalonia UI https://github.com/AvaloniaUI/Avalonia/blob/master/readme.md

(Not affiliated but I love this project. If it wasn't still alpha I'd use it for absolutely everything)

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