Move dispatch dimensions and vertex count to new DispatchParameters with defaults#1153
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| case ShaderPipelineKind::TraditionalRaster: | ||
| if (DispatchParameters.DispatchGroupCount != | ||
| std::array<uint32_t, 3>{1, 1, 1}) | ||
| return llvm::createStringError( | ||
| "DispatchParameters.DispatchGroupCount set on a TraditionalRaster " | ||
| "pipeline. Only allowed on a Compute pipeline."); | ||
| break; |
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Should we validate that VertexCount is not set if a vertex buffer was provided, or are there sensible reasons to override the "default" number of vertices in a buffer?
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There are valid reasons to specify this manually even though you have defined a vertex buffer. Especially when we start passing arguments like FirstVertex.
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The only validation would be if FirstVertex + VertexCount <= NumVerticesInBuffer perhaps?
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Technically that would still be a valid case though, but you would be reading zeroes.
…at happens when you do.
MarijnS95
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DispatchParameters. Allow more flexibility and introduce useful default values.DispatchParameters with defaults
bogner
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Fixes #1152
There was no way to specify the vertex count for a test that uses the TraditionalRaster pipeline.
Since vertex buffers are not required for doing rasterization, and is actually quite a common use case, we need to be able to specify that as well.
In the future we will also need to support indexed and instanced draws, for which more parameters need to be specified.
Specifying these parameters are part of the shader doesn't really make sense since they apply to the whole pipeline.
For those reasons I am introducing a
DispatchParametersfield where the user can specify the exact parameters for how a pipeline should be dispatched.While making this change I found that 99% of the compute shader tests dispatch a single threadgroup. Since there is no use-case for dispatching no threads (as far as I am aware), I made dispatching a single thread group a default value. This simplifies writing tests.
For TraditionalRaster tests we can still rely on calculating the vertex count from the size of the vertex buffer and vertex stride if it is not specified in the .yaml section.