Graphics context management

[kekekeks]

• graphics contexts are now owned by the Compositor (it's still possible to use a shared context)
• WinUI composition now exposes IDirect3D11TexturePlatformSurface instead of EGL one and re-creates a composition device when needed
• OpenGL control now works for iOS and Linux framebuffer
• various refactorings
• fixed DPI reported by WriteableBitmap.Lock()

To survive a driver reset, our renderers need to be able to recreate the entire graphics infrastructure from scratch.
We also have a problem with graphics subsystem initialization blocking the rest of our initialization code on the UI thread, which is hurtful for embedded scenarious where initial GPU initialization might take some time due to drviver init, connected display scans, etc. So we'd rather initialize the GPU stuff on the render thread.
To do that, we need the renderer to be in control of the graphics resources rather than holding those in some static fields in SkiaPlatform.

  // The general interface for providing optional features. We can't really rely on type casts since
  // some features might be aggregated from other classes and C# doesn't support multi-inheritance nor
  // something like COM interface aggregation
  interface IFeatureProvider
  {
    object GetFeature(Type t);
  }

  interface IPlatformGraphics : IFeatureProvider
  {
    IPlatformGraphicsContext GetSharedContext();
    IPlatformGraphicsContext CreateContext();
  }
  
  // Can be IGlContext, ISkiaGpu or our new vulkan thingy
  interface IPlatformGraphicsContext : IDisposable, IFeatureProvider
  {
    bool IsLost { get; }
    // This is needed to make sure that we can dispose layers
    // outside of IRenderTarget-bound drawing session
    IDisposable EnsureCurrent();
  }
  
  interface IPlatformRenderInterface
  {
    // Instead of being initialized at startup it now wraps IPlatformGraphicsContext into IRenderingContext
    // which serves as a factory for render targets and layers
    IRenderingContext CreateRenderingContext(IPlatformGpuContext gpuContext);
  }
  interface IRenderingContext : IFeatureProvider, IDisposable
  {
    bool IsCorrupted { get; }
    IRenderTarget CreateRenderTarget(IEnumerable<object> surfaces);
    object GetFeature(Type t);
  }

Compositor would accept IPlatformGraphics directly, Deferred and Immediate renderers would use a wrapper object that creates the context on-demand

Renderer would be the sole entity that holds a reference to the graphics context. That causes a problem with texture-sharing powered opengl controls. For such controls the render platform context should expose:

    public interface IOpenGlTextureSharingRenderInterfaceContextFeature
    {
        bool CanCreateSharedContext { get; }
        IGlContext CreateSharedContext(IEnumerable<GlVersion> preferredVersions = null);
        IOpenGlBitmapImpl CreateOpenGlBitmap(PixelSize size, Vector dpi);
    }

while IRenderer now has

        public ValueTask<object?> TryGetRenderInterfaceFeature(Type featureType);

In case when the user wants to reuse their VkDevice, a similar interface will be provided as well. ValueTask is here due to the renderer potentially ticking on a background thread, so if context wasn't yet created, we need to wait for the next renderer tick.

Fixes #4128 #8320

[avaloniaui-team]

You can test this PR using the following package version. 11.0.999-cibuild0027151-beta. (feed url: https://pkgs.dev.azure.com/AvaloniaUI/AvaloniaUI/_packaging/avalonia-nightly/nuget/v3/index.json) [PRBUILDID]

[avaloniaui-team]

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[maxkatz6]

API-wise, what's a point of SupportsMultipleContexts = true when IPlatformGraphics.CreateContext always throws an exception?

[kekekeks]

There is a difference between DrmOutput and EglDisplay

• DrmOutput uses a pre-existing context to produce a render target and that can not use any other context to use said render target
• EglDisplay needs to know if the native EGLDisplay can be trusted to create multiple contexts (which is the case here).

For example ANGLE uses single ID3D11Device for all contexts created from a single EGLDisplay which causes threading issues and native crashes, so we can't trust it to create multiple contexts properly.

We can change DrmOutput.CreateContext to allow context creation, but those contexts would be kinda useless.

[maxkatz6]

I want to remove JetBrains.Annotations at all from the repository. It can be and should be replaced with nullable attributes.
Out of scope of this PR tho.

[avaloniaui-team]

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[danipen]

@kekekeks does this PR fix Avalonia's OpenGL control rendering issues in windows os?

[avaloniaui-team]

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[kekekeks]

No, this particular PR just fixes EGL_CONTEXT_LOST and provides better infrastructure for adding rendering backends

[danipen]

@kekekeks are there any plans for fixing OpenGL control rendering issues in windows os soon?

[danwalmsley]

@kekekeks are there any plans for fixing OpenGL control rendering issues in windows os soon?

@danipen that is also actively being worked on :)

[danipen]

That's awesome thanks!

[avaloniaui-team]

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[ltetak]

see if you can break this with this DX commandline command
DXCap.exe -forcetdr

[avaloniaui-team]

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[maxkatz6]

@ltetak it works with normal avalonia setup. But segfaults with UseWGL enabled with no meaningful error.

[avaloniaui-team]

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[avaloniaui-team]

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