shader: extract 9-bit NGG primitive vertex indices, leaving the edge flags out

This commit is contained in:
Senaxx
2026-10-23 13:28:23 +02:00
committed by nmzik
parent ecc30a1f2d
commit 706aa030ad
2 changed files with 3 additions and 1 deletions
@@ -187,7 +187,7 @@ void EmitMeshEntryPoint(EmitterState& state) {
vertex[component] = state.builder.AllocateId();
state.builder.AddFunction(
spv::OpBitFieldUExtract, TypeU32(state), vertex[component], packed,
ConstantU32(state, component * 10u), ConstantU32(state, 10));
ConstantU32(state, component * 10u), ConstantU32(state, 9));
}
const auto triangle = state.builder.AllocateId();
state.builder.AddFunction(spv::OpCompositeConstruct, TypeU32Vector(state, 3), triangle,
+2
View File
@@ -11160,6 +11160,8 @@ void TestMeshExportStorage() {
!SpirvSourceHasInstructionUsing(source, "OpAccessChain",
"vsharp %uint_0 %uint_4294967295"),
"mesh draw prefix was lost or spilled shader data wrapped into push constants");
Check(SpirvSourceHasInstructionUsing(source, "OpBitFieldUExtract", "%uint_10 %uint_9"),
"NGG primitive vertex indices must be 9 bits; bit 9 of each field is the edge flag");
const auto &binary = result.spirv;
for (const auto builtin : {3u, 4u}) {
auto expected = builtin == 3u ? std::vector<uint32_t>{0, 3}