1325835 - DXGL ShSurf fails to Attach on Intel

Status: RESOLVED FIXED

(Core :: Graphics: CanvasWebGL, defect, P2)

Description

[Kelsey Gilbert [:jgilbert]]

When ANGLE is disabled, we try to use native GL and get fast compositing with DXGI sharing.

When we build an FB with this dx_interop2 renderbuffer and a depth RB, we're getting GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE, which causes us to force-lose the webgl context.

Comment 1

[Kelsey Gilbert [:jgilbert]]

I think this is really a bug in Intel's implementation of dx_interop, but they seem excruciatingly technically correct.

D3D textures are created with D3D11_TEXTURE2D_DESC.
D3D11_TEXTURE2D_DESC::SampleDesc defaults to the "default sampler mode, with no anti-aliasing, has a count of 1 and a quality level of 0."[1]

It seems when we register a dx_interop GL_RENDERBUFFER from it, it gets RENDERBUFFER_SAMPLES=1, not 0.
In GL, samples=1 is still considered 'multisampled', so we can't attach it to an FB with samples=0, and we can't switch to using samples=1 because BlitFramebuffer forbids its DRAW_FRAMEBUFFER from samples>0.

Since I can't think of another way in GL to efficiently get data into a samples>0 resource, we'll have to have a temporary samples=0 GL_TEXTURE to resolve into, and then draw-blit it into our samples=1 dx_interop GL_RENDERBUFFER.

[1]: https://msdn.microsoft.com/en-us/library/windows/desktop/bb173072(v=vs.85).aspx
 {
  UINT             Width;
  UINT             Height;
  UINT             MipLevels;
  UINT             ArraySize;
  DXGI_FORMAT      Format;
  DXGI_SAMPLE_DESC SampleDesc;

Comment 2

[Kelsey Gilbert [:jgilbert]]

Attachment: Bug 1325835 - Support dx_interop on Intel. -

Review commit: https://reviewboard.mozilla.org/r/101414/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/101414/

Comment 3

[Jeff Muizelaar [:jrmuizel]]

Comment on attachment 8822539 [details]
Bug 1325835 - Support dx_interop on Intel. -

https://reviewboard.mozilla.org/r/101414/#review106746

::: gfx/gl/SharedSurfaceD3D11Interop.cpp:320
(Diff revision 1)
> +        {
> +            const ScopedBindRenderbuffer bindRB(gl, interopRB);
> +            gl->fGetRenderbufferParameteriv(LOCAL_GL_RENDERBUFFER,
> +                                            LOCAL_GL_RENDERBUFFER_SAMPLES, &samples);
> +        }
> +        if (samples > 0) { // Intel

Can you add the description of the problem that you give in the bug as a comment here. It would also be good to reach out to Intel and ask them to change what they're doing.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/661cad778f95
Support dx_interop on Intel. - r=jrmuizel

Comment 5

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/661cad778f95