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858c928ac7
This obsoletes WIP PR #704, which was built on the pre entry point wrapping master. New version here uses entry point wrapping. This is a limited implementation of tessellation shaders. In particular, the following are not functional, and will be added as separate stages to reduce the size of each PR. * patchconstantfunctions accepting per-control-point input values, such as const OutputPatch <hs_out_t, 3> cpv are not implemented. * patchconstantfunctions whose signature requires an aggregate input type such as a structure containing builtin variables. Code to synthesize such calls is not yet present. These restrictions will be relaxed as soon as possible. Simple cases can compile now: see for example Test/hulsl.hull.1.tesc - e.g, writing to inner and outer tessellation factors. PCF invocation is synthesized as an entry point epilogue protected behind a barrier and a test on invocation ID == 0. If there is an existing invocation ID variable it will be used, otherwise one is added to the linkage. The PCF and the shader EP interfaces are unioned and builtins appearing in the PCF but not the EP are also added to the linkage and synthesized as shader inputs. Parameter matching to (eventually arbitrary) PCF signatures is by builtin variable type. Any user variables in the PCF signature will result in an error. Overloaded PCF functions will also result in an error. [domain()], [partitioning()], [outputtopology()], [outputcontrolpoints()], and [patchconstantfunction()] attributes to the shader entry point are in place, with the exception of the Pow2 partitioning mode.
40 lines
663 B
GLSL
40 lines
663 B
GLSL
// ***
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// invocation ID coming from input to entry point
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// ***
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struct VS_OUT
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{
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float3 cpoint : CPOINT;
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};
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struct HS_CONSTANT_OUT
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{
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float edges[2] : SV_TessFactor;
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};
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struct HS_OUT
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{
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float3 cpoint : CPOINT;
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};
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[domain("isoline")]
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[partitioning("integer")]
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[outputtopology("line")]
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[outputcontrolpoints(4)]
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[patchconstantfunc("PCF")]
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HS_OUT main(InputPatch<VS_OUT, 4> ip, uint m_cpid : SV_OutputControlPointID)
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{
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HS_OUT output;
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output.cpoint = ip[0].cpoint;
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return output;
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}
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HS_CONSTANT_OUT PCF(uint pid : SV_PrimitiveId)
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{
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HS_CONSTANT_OUT output;
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output.edges[0] = 2.0f;
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output.edges[1] = 8.0f;
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return output;
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}
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