WaveGetWaveIndex
Description
Returns the index of the current wave (subgroup) within the workgroup. Equivalent to GLSL gl_SubgroupID / Metal simdgroup_index_in_threadgroup.
On GLSL and SPIR-V this lowers to gl_SubgroupID / BuiltIn SubgroupId, which are restricted to compute-class execution models (compute, mesh, amplification); using it from any other stage is a capability error.
Signature
uint WaveGetWaveIndex();
Availability and Requirements
Defined for the following targets:
hlsl
Available in all stages.
glsl
Available in stages: amplification, mesh, compute.
cuda
Available in all stages.
metal
Available in all stages.
wgsl
Available in all stages.
spirv
Available in stages: amplification, mesh, compute.
Requires capabilities: spvGroupNonUniform, spvMeshShadingEXT.