Split shader generation to a new module

include/Nazara/Shader/SpirvWriter.hpp

@@ -0,0 +1,132 @@
+// Copyright (C) 2020 Jérôme Leclercq
+// This file is part of the "Nazara Engine - Shader generator"
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#pragma once
+
+#ifndef NAZARA_SPIRVWRITER_HPP
+#define NAZARA_SPIRVWRITER_HPP
+
+#include <Nazara/Prerequisites.hpp>
+#include <Nazara/Shader/Config.hpp>
+#include <Nazara/Shader/ShaderAst.hpp>
+#include <Nazara/Shader/ShaderAstVisitor.hpp>
+#include <Nazara/Shader/ShaderVarVisitor.hpp>
+#include <Nazara/Shader/ShaderWriter.hpp>
+#include <Nazara/Utility/FieldOffsets.hpp>
+#include <string>
+#include <string_view>
+#include <unordered_map>
+
+namespace Nz
+{
+	class NAZARA_SHADER_API SpirvWriter : public ShaderAstVisitor, public ShaderVarVisitor
+	{
+		public:
+			struct Environment;
+
+			SpirvWriter();
+			SpirvWriter(const SpirvWriter&) = delete;
+			SpirvWriter(SpirvWriter&&) = delete;
+			~SpirvWriter() = default;
+
+			std::vector<UInt32> Generate(const ShaderAst& shader);
+
+			void SetEnv(Environment environment);
+
+			struct Environment
+			{
+				UInt32 spvMajorVersion = 1;
+				UInt32 spvMinorVersion = 0;
+			};
+
+		private:
+			struct ExtVar;
+			struct Opcode;
+			struct Raw;
+			struct WordCount;
+
+			struct Section
+			{
+				inline std::size_t Append(const char* str);
+				inline std::size_t Append(const std::string_view& str);
+				inline std::size_t Append(const std::string& str);
+				inline std::size_t Append(UInt32 value);
+				std::size_t Append(const Opcode& opcode, const WordCount& wordCount);
+				std::size_t Append(const Raw& raw);
+				inline std::size_t Append(std::initializer_list<UInt32> codepoints);
+				template<typename... Args> std::size_t Append(Opcode opcode, const Args&... args);
+				template<typename T> std::size_t Append(T value);
+
+				inline unsigned int CountWord(const char* str);
+				inline unsigned int CountWord(const std::string_view& str);
+				inline unsigned int CountWord(const std::string& str);
+				unsigned int CountWord(const Raw& raw);
+				template<typename T> unsigned int CountWord(const T& value);
+				template<typename T1, typename T2, typename... Args> unsigned int CountWord(const T1& value, const T2& value2, const Args&... rest);
+
+				inline std::size_t GetOutputOffset() const;
+
+				std::vector<UInt32> data;
+			};
+
+			UInt32 AllocateResultId();
+
+			void AppendConstants();
+			void AppendHeader();
+			void AppendStructType(std::size_t structIndex, UInt32 resultId);
+			void AppendTypes();
+
+			UInt32 EvaluateExpression(const ShaderNodes::ExpressionPtr& expr);
+
+			UInt32 GetConstantId(const ShaderNodes::Constant::Variant& value) const;
+			UInt32 GetTypeId(const ShaderExpressionType& type) const;
+
+			void PushResultId(UInt32 value);
+			UInt32 PopResultId();
+
+			UInt32 ReadVariable(ExtVar& var);
+			UInt32 RegisterType(ShaderExpressionType type);
+
+			using ShaderAstVisitor::Visit;
+			void Visit(ShaderNodes::AccessMember& node) override;
+			void Visit(ShaderNodes::AssignOp& node) override;
+			void Visit(ShaderNodes::Branch& node) override;
+			void Visit(ShaderNodes::BinaryOp& node) override;
+			void Visit(ShaderNodes::Cast& node) override;
+			void Visit(ShaderNodes::Constant& node) override;
+			void Visit(ShaderNodes::DeclareVariable& node) override;
+			void Visit(ShaderNodes::ExpressionStatement& node) override;
+			void Visit(ShaderNodes::Identifier& node) override;
+			void Visit(ShaderNodes::IntrinsicCall& node) override;
+			void Visit(ShaderNodes::Sample2D& node) override;
+			void Visit(ShaderNodes::StatementBlock& node) override;
+			void Visit(ShaderNodes::SwizzleOp& node) override;
+
+			using ShaderVarVisitor::Visit;
+			void Visit(ShaderNodes::BuiltinVariable& var) override;
+			void Visit(ShaderNodes::InputVariable& var) override;
+			void Visit(ShaderNodes::LocalVariable& var) override;
+			void Visit(ShaderNodes::OutputVariable& var) override;
+			void Visit(ShaderNodes::ParameterVariable& var) override;
+			void Visit(ShaderNodes::UniformVariable& var) override;
+
+			static void MergeBlocks(std::vector<UInt32>& output, const Section& from);
+
+			struct Context
+			{
+				const ShaderAst* shader = nullptr;
+				const ShaderAst::Function* currentFunction = nullptr;
+			};
+
+			struct State;
+
+			Context m_context;
+			Environment m_environment;
+			State* m_currentState;
+	};
+}
+
+#include <Nazara/Shader/SpirvWriter.inl>
+
+#endif