From 25562a5856315a70fe5ceab57065a6d1ff108bfc Mon Sep 17 00:00:00 2001
From: Lynix <lynix680@gmail.com>
Date: Thu, 4 Jun 2020 18:29:50 +0200
Subject: [PATCH] Renderer/ShaderAst: Add BinaryFunc

---
 include/Nazara/Renderer/GlslWriter.hpp |  1 +
 include/Nazara/Renderer/ShaderAst.hpp  | 25 +++++++++++++++++++++++-
 include/Nazara/Renderer/ShaderAst.inl  | 23 ++++++++++++++++++++++
 src/Nazara/Renderer/ShaderAst.cpp      | 27 ++++++++++++++++++++++++++
 4 files changed, 75 insertions(+), 1 deletion(-)

diff --git a/include/Nazara/Renderer/GlslWriter.hpp b/include/Nazara/Renderer/GlslWriter.hpp
index 13d7c8459..373a9950e 100644
--- a/include/Nazara/Renderer/GlslWriter.hpp
+++ b/include/Nazara/Renderer/GlslWriter.hpp
@@ -33,6 +33,7 @@ namespace Nz
 
 			void Write(const ShaderAst::AssignOp& node) override;
 			void Write(const ShaderAst::Branch& node) override;
+			void Write(const ShaderAst::BinaryFunc& node) override;
 			void Write(const ShaderAst::BinaryOp& node) override;
 			void Write(const ShaderAst::BuiltinVariable& node) override;
 			void Write(const ShaderAst::Cast& node) override;
diff --git a/include/Nazara/Renderer/ShaderAst.hpp b/include/Nazara/Renderer/ShaderAst.hpp
index 08e8e20b2..6dd43ea89 100644
--- a/include/Nazara/Renderer/ShaderAst.hpp
+++ b/include/Nazara/Renderer/ShaderAst.hpp
@@ -26,13 +26,20 @@ namespace Nz
 			Simple //< =
 		};
 
+		enum class BinaryIntrinsic
+		{
+			CrossProduct,
+			DotProduct
+		};
+
 		enum class BinaryType
 		{
 			Add,       //< +
 			Substract, //< -
 			Multiply,  //< *
 			Divide,    //< /
-			Equality   //< ==
+
+			Equality  //< ==
 		};
 
 		enum class BuiltinEntry
@@ -325,6 +332,22 @@ namespace Nz
 				ExpressionPtr sampler;
 				ExpressionPtr coordinates;
 		};
+
+		//////////////////////////////////////////////////////////////////////////
+
+		class NAZARA_RENDERER_API BinaryFunc : public Expression
+		{
+			public:
+				inline BinaryFunc(BinaryIntrinsic Op, ExpressionPtr Left, ExpressionPtr Right);
+
+				ExpressionType GetExpressionType() const override;
+				void Register(ShaderWriter& visitor) override;
+				void Visit(ShaderWriter& visitor) override;
+
+				BinaryIntrinsic intrinsic;
+				ExpressionPtr   left;
+				ExpressionPtr   right;
+		};
 	}
 }
 
diff --git a/include/Nazara/Renderer/ShaderAst.inl b/include/Nazara/Renderer/ShaderAst.inl
index e837cbdb4..958baecfe 100644
--- a/include/Nazara/Renderer/ShaderAst.inl
+++ b/include/Nazara/Renderer/ShaderAst.inl
@@ -243,6 +243,29 @@ namespace Nz
 			if (coordinates->GetExpressionType() != ExpressionType::Float2)
 				throw std::runtime_error("Coordinates must be a Float2");
 		}
+
+		inline BinaryFunc::BinaryFunc(BinaryIntrinsic Op, ExpressionPtr Left, ExpressionPtr Right) :
+		intrinsic(Op),
+		left(Left),
+		right(Right)
+		{
+			ExpressionType leftType = left->GetExpressionType();
+			ExpressionType rightType = right->GetExpressionType();
+
+			if (leftType != rightType)
+				//TODO: AstParseError
+				throw std::runtime_error("Left expression type must match right expression type");
+
+			switch (intrinsic)
+			{
+				case BinaryIntrinsic::CrossProduct:
+				{
+					if (leftType != ExpressionType::Float3)
+						//TODO: AstParseError
+						throw std::runtime_error("CrossProduct only works with Float3 expressions");
+				}
+			}
+		}
 	}
 }
 
diff --git a/src/Nazara/Renderer/ShaderAst.cpp b/src/Nazara/Renderer/ShaderAst.cpp
index a0a0cc031..0a2373d17 100644
--- a/src/Nazara/Renderer/ShaderAst.cpp
+++ b/src/Nazara/Renderer/ShaderAst.cpp
@@ -254,4 +254,31 @@ namespace Nz::ShaderAst
 	{
 		visitor.Write(*this);
 	}
+
+
+	ExpressionType BinaryFunc::GetExpressionType() const
+	{
+		switch (intrinsic)
+		{
+			case BinaryIntrinsic::CrossProduct:
+				return left->GetExpressionType();
+
+			case BinaryIntrinsic::DotProduct:
+				return ExpressionType::Float1;
+		}
+
+		NazaraAssert(false, "Unhandled builtin");
+		return ExpressionType::Void;
+	}
+
+	void BinaryFunc::Register(ShaderWriter& visitor)
+	{
+		left->Register(visitor);
+		right->Register(visitor);
+	}
+
+	void BinaryFunc::Visit(ShaderWriter& visitor)
+	{
+		visitor.Write(*this);
+	}
 }