diff options
| -rw-r--r-- | docs/design/stdlib-intrinsics.md | 2 | ||||
| -rw-r--r-- | source/slang/hlsl.meta.slang | 25 |
2 files changed, 26 insertions, 1 deletions
diff --git a/docs/design/stdlib-intrinsics.md b/docs/design/stdlib-intrinsics.md index 76614beba..8d78de504 100644 --- a/docs/design/stdlib-intrinsics.md +++ b/docs/design/stdlib-intrinsics.md @@ -87,7 +87,7 @@ Currently `HLSL` has a special handling in that it is *assumed* if a declaration The target can also be a capability atom. The atoms are listed in "slang-capability-defs.h". -What is perhaps of importance here is that for some features for a specific target can have multiple ways of achieving the same effect - for example "GL_NV_ray_tracing" or "GL_NV_ray_tracing" are two different ray tracing extensions available for Vulkan through GLSL. The `-profile` option can disambiguate which extension is actually desired, and the capability with that name on the `target_intrinsic` specifies how to implement that feature for that specific extension. +What is perhaps of importance here is that for some features for a specific target can have multiple ways of achieving the same effect - for example "GL_NV_ray_tracing" and "GL_EXT_ray_tracing" are two different ray tracing extensions available for Vulkan through GLSL. The `-profile` option can disambiguate which extension is actually desired, and the capability with that name on the `target_intrinsic` specifies how to implement that feature for that specific extension. The expansion mechanism is implemented in "slang-intrinsic-expand.cpp" which will be most up to date. diff --git a/source/slang/hlsl.meta.slang b/source/slang/hlsl.meta.slang index 144141b79..2f4064c97 100644 --- a/source/slang/hlsl.meta.slang +++ b/source/slang/hlsl.meta.slang @@ -9861,6 +9861,31 @@ uint GeometryIndex() } } +// Get the vertex positions of the currently hit triangle in any-hit or closest-hit shader. +// https://github.com/KhronosGroup/GLSL/blob/master/extensions/ext/GLSL_EXT_ray_tracing_position_fetch.txt +__glsl_extension(GL_EXT_ray_tracing) +__glsl_extension(GL_EXT_ray_tracing_position_fetch) +__glsl_version(460) +[ForceInline] +float3 HitTriangleVertexPosition(uint index) +{ + __target_switch + { + case glsl: + __intrinsic_asm "gl_HitTriangleVertexPositionsEXT[$0]"; + case spirv: + return spirv_asm { + OpCapability RayTracingKHR; + OpCapability RayTracingPositionFetchKHR; + OpExtension "SPV_KHR_ray_tracing"; + OpExtension "SPV_KHR_ray_tracing_position_fetch"; + %_ptr_Input_v3float = OpTypePointer Input $$float3; + %addr : %_ptr_Input_v3float = OpAccessChain builtin(HitTriangleVertexPositionsKHR:float3[3]) $index; + result:$$float3 = OpLoad %addr; + }; + } +} + // Status of whether a (closest) hit has been committed in a `RayQuery`. typedef uint COMMITTED_STATUS; |