shader: Implement front face

This commit is contained in:
ReinUsesLisp 2021-03-27 02:55:37 -03:00 committed by ameerj
parent a806b29cb9
commit f0031babeb
5 changed files with 12 additions and 0 deletions

View file

@ -302,6 +302,9 @@ void EmitContext::DefineInputs(const Info& info) {
base_vertex = DefineInput(*this, U32[1], spv::BuiltIn::BaseVertex);
}
}
if (info.loads_front_face) {
front_face = DefineInput(*this, U1, spv::BuiltIn::FrontFacing);
}
for (size_t index = 0; index < info.loads_generics.size(); ++index) {
if (!info.loads_generics[index]) {
continue;

View file

@ -94,6 +94,7 @@ public:
Id vertex_id{};
Id vertex_index{};
Id base_vertex{};
Id front_face{};
Id input_position{};
std::array<Id, 32> input_generics{};

View file

@ -156,6 +156,10 @@ Id EmitGetAttribute(EmitContext& ctx, IR::Attribute attr) {
return ctx.OpISub(ctx.U32[1], ctx.OpLoad(ctx.U32[1], ctx.vertex_index),
ctx.OpLoad(ctx.U32[1], ctx.base_vertex));
}
case IR::Attribute::FrontFace:
return ctx.OpSelect(ctx.U32[1], ctx.OpLoad(ctx.U1, ctx.front_face),
ctx.Constant(ctx.U32[1], std::numeric_limits<u32>::max()),
ctx.u32_zero_value);
default:
throw NotImplementedException("Read attribute {}", attr);
}

View file

@ -44,6 +44,9 @@ void GetAttribute(Info& info, IR::Attribute attribute) {
case IR::Attribute::VertexId:
info.loads_vertex_id = true;
break;
case IR::Attribute::FrontFace:
info.loads_front_face = true;
break;
default:
throw NotImplementedException("Get attribute {}", attribute);
}

View file

@ -62,6 +62,7 @@ struct Info {
bool loads_position{};
bool loads_instance_id{};
bool loads_vertex_id{};
bool loads_front_face{};
std::array<bool, 8> stores_frag_color{};
bool stores_frag_depth{};