| // Copyright 2020 The Tint Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "src/transform/emit_vertex_point_size.h" |
| |
| #include <utility> |
| |
| #include "src/ast/assignment_statement.h" |
| #include "src/program_builder.h" |
| |
| namespace tint { |
| namespace transform { |
| |
| EmitVertexPointSize::EmitVertexPointSize() = default; |
| EmitVertexPointSize::~EmitVertexPointSize() = default; |
| |
| Output EmitVertexPointSize::Run(const Program* in, const DataMap&) { |
| if (!in->AST().Functions().HasStage(ast::PipelineStage::kVertex)) { |
| // If the module doesn't have any vertex stages, then there's nothing to do. |
| return Output(Program(in->Clone())); |
| } |
| |
| ProgramBuilder out; |
| |
| CloneContext ctx(&out, in); |
| |
| Symbol pointsize = out.Symbols().New("tint_pointsize"); |
| |
| // Declare the pointsize builtin output variable. |
| out.Global(pointsize, out.ty.f32(), ast::StorageClass::kOutput, nullptr, |
| ast::DecorationList{ |
| out.create<ast::BuiltinDecoration>(ast::Builtin::kPointSize), |
| }); |
| |
| // Add the pointsize assignment statement to the front of all vertex stages. |
| ctx.ReplaceAll([&](ast::Function* func) -> ast::Function* { |
| if (func->pipeline_stage() != ast::PipelineStage::kVertex) { |
| return nullptr; // Just clone func |
| } |
| |
| return CloneWithStatementsAtStart(&ctx, func, |
| { |
| out.Assign(pointsize, 1.0f), |
| }); |
| }); |
| ctx.Clone(); |
| |
| return Output(Program(std::move(out))); |
| } |
| |
| } // namespace transform |
| } // namespace tint |