Full GPU rendering in WPF

[JPDelprat]

Hello,

I'm desperately in search of the best solution for full GPU rendering with WPF :

• HWND hosting based solutions cannot be used because they are not integrated in WPF pipeline, but rendered in an overlay (so I cannot show WPF controls on top of my SkiaSharp rendering),
• Rendering to an Off-screen WGL context than doing a CPU blit works, but it is not 100% GPU
• Angle works but as rendering is slower than with WGL, I get the same performance than previous solution

I'm trying to create a D3D12 texture for Skiasharp shared as a D3D9 texture to associate to a WPF D3DImage, but after many many tries, it never work.

• Is there a way to use Skiasharp with D3D9 ?
• Is there a way to fasten Angle ? Which D3D version Angle uses by default ? Can I modify the D3D version and get better results ?
• Did someone manage to create a D3D12 texture shared with D3D9 ?
• Is it possible instead to create a D3D9 texture, shared it with D3D12 and make SkiaSharp uses this D3D12 texture ?
• Other solutions for full gpu rendering without HWND overlay ?

Thank you

PS : constraint, I am forced to work with .net framework 4.7

[JPDelprat]

I have found a work very efficient 100% GPU solution.

I've created a D3D9 texture, shared it with D3D12. D3D9 texture is set as backbuffer in a D3DIMage. SkiaSharp uses the D3D12 texture.

That said : this 100% GPU solution is not faster than rendering to a off-screen WGL (Windows OpenGl) surface than doing a cpu blit to a WriteableBitmap.

So same performance than Angle which is also 100% GPU.

[JPDelprat]

I've finally found a faster 100% GPU solution.

D3D9 texture shared as WGL texture (NV_DX_Interop).
SkiaSharp rendering to WGL texture.
WPF D3D image using D3D9 texture as back buffer.

=> 10ms faster than WGL offscreen rendering + CPU blit to writeable bitmap

[JPDelprat]

I know this is not what you expected ;-)

I really spent many many days to find the best solution.
It is easy to implement it from the code I've provided above.

If I can find some time, I will create a working sample, but not at this time.
Sorry.

Regards,

[mattleibow]

Thanks for sharing! I also really want to find some time to do this. I wonder if this can also be done in C# with one of the DX interop libraries.

[JPDelprat]

I’m fairly confident this can be achieved using interop libraries, but rather than redeclaring everything, I chose to use managed C++ instead.

I am using .net 4.7, and SharpDX has some invalid declarations.
If you are using .net core, Vortice is probably a better choice.

You have to interop with both DirectX9 and WGL.

[KaFo]

Getting efficient, working GPU-based rendering in WPF finally after all these years would really be a blast. (I gave up hope about a decade ago.)

For DirectX Interop: I'm happy with https://github.com/smourier/DirectN. Especially if you need NET.Framework support. For AOT there's also https://github.com/smourier/DirectNAot. I like the approach of having auto generated 1:1 DirectX methods with exact same signature as the original COM classes plus simple extensions methods with "nicer" wrappers where needed:

1. HRESULT CreateTexture2D(ref D3D11_TEXTURE2D_DESC pDesc, 3D11_SUBRESOURCE_DATA[] pInitialData, out ID3D11Texture2D ppTexture2D); (auto generated)
2. IComObject<ID3D11Texture2D> CreateTexture2D(D3D11_TEXTURE2D_DESC pDesc, 3D11_SUBRESOURCE_DATA[] pInitialData=null) (wrapper. throws exception on errors, returns disposable wrapper around ID3D11Texture2D)

[JPDelprat]

Thank you very much for the information. DirectN looks really interesting.

That said, I currently prefer to migrate my interop code to managed C++ once it starts getting a bit more complex, since creating a managed C++ DLL is straightforward and allows me to use native APIs whenever I need to.