|
|
Mario Kart World draws some of its geometry with NVN task and mesh programs
(the task program culls and writes the mesh workgroup count and a payload
to its stage buffer; each mesh workgroup reads it back and writes vertices
and primitives). Add Task and Mesh stages and translate them for
VK_EXT_mesh_shader:
- the ISBE pseudo instruction from the lowering becomes reads and writes
of an emulated stage buffer: the task's output region is the task
payload, the mesh output regions live in workgroup memory
- every EXIT of these stages jumps to one final return, so all
invocations reach the epilogue: a barrier, then OpEmitMeshTasksEXT, or
OpSetMeshOutputsEXT and a copy of the 32-element vertex and primitive
groups (lines named by the mesh header's and the pass-through geometry
header's output maps) to arrayed and per-primitive outputs
- Sirit lacks the two mesh instructions: they are emitted as OpStore
markers and replaced after assembly
- fragment inputs a mesh program writes per primitive get PerPrimitiveEXT
The captured task and mesh programs of the title translate to SPIR-V that
spirv-val accepts.
|
