Maths for HLSL BxDFs (template cmath, tgmath)

include/nbl/builtin/hlsl/array_accessors.hlsl

@@ -0,0 +1,30 @@
+#ifndef _NBL_BUILTIN_HLSL_ARRAY_ACCESSORS_HLSL_INCLUDED_
+#define _NBL_BUILTIN_HLSL_ARRAY_ACCESSORS_HLSL_INCLUDED_
+
+#include <nbl/builtin/hlsl/cpp_compat/basic.h>
+
+namespace nbl
+{
+namespace hlsl
+{
+template<typename ArrayType, typename ComponentType, typename I = uint32_t>
+struct array_get
+{
+    ComponentType operator()(NBL_CONST_REF_ARG(ArrayType) arr, const I ix) NBL_CONST_MEMBER_FUNC
+    {
+        return arr[ix];
+    }
+};
+
+template<typename ArrayType, typename ComponentType, typename I = uint32_t>
+struct array_set
+{
+    void operator()(NBL_REF_ARG(ArrayType) arr, I index, ComponentType val) NBL_CONST_MEMBER_FUNC
+    {
+        arr[index] = val;
+    }
+};
+}
+}
+
+#endif

include/nbl/builtin/hlsl/cpp_compat.hlsl

@@ -3,7 +3,7 @@
 
 #include <nbl/builtin/hlsl/cpp_compat/basic.h>
 // it includes vector and matrix
-#include <nbl/builtin/hlsl/cpp_compat/intrinsics.h>
+#include <nbl/builtin/hlsl/cpp_compat/intrinsics.hlsl>
 #include <nbl/builtin/hlsl/cpp_compat/promote.hlsl>
 
 #endif

include/nbl/builtin/hlsl/cpp_compat/basic.h

@@ -55,8 +55,12 @@ namespace nbl::hlsl
 
 // We need variadic macro in order to handle multi parameter templates because the 
 // preprocessor parses the template parameters as different macro parameters.
-#define NBL_REF_ARG(...) typename nbl::hlsl::add_reference<__VA_ARGS__ >::type
-#define NBL_CONST_REF_ARG(...) typename nbl::hlsl::add_reference<std::add_const_t<__VA_ARGS__ >>::type
+#define NBL_REF_ARG(...) __VA_ARGS__&
+#define NBL_CONST_REF_ARG(...) const __VA_ARGS__&
+
+// NOTE: implementation below will mess up template parameter deduction
+//#define NBL_REF_ARG(...) typename nbl::hlsl::add_reference<__VA_ARGS__ >::type
+//#define NBL_CONST_REF_ARG(...) typename nbl::hlsl::add_reference<std::add_const_t<__VA_ARGS__ >>::type
 
 #else
 

include/nbl/builtin/hlsl/cpp_compat/impl/intrinsics_impl.hlsl

@@ -0,0 +1,301 @@
+#ifndef _NBL_BUILTIN_HLSL_CPP_COMPAT_IMPL_INTRINSICS_IMPL_INCLUDED_
+#define _NBL_BUILTIN_HLSL_CPP_COMPAT_IMPL_INTRINSICS_IMPL_INCLUDED_
+
+namespace nbl
+{
+namespace hlsl
+{
+namespace cpp_compat_intrinsics_impl
+{
+template<typename T>
+struct dot_helper
+{
+	using scalar_type = typename vector_traits<T>::scalar_type;
+
+	static inline scalar_type dot(NBL_CONST_REF_ARG(T) lhs, NBL_CONST_REF_ARG(T) rhs)
+	{
+		static array_get<T, scalar_type> getter;
+		scalar_type retval = getter(lhs, 0) * getter(rhs, 0);
+
+		static const uint32_t ArrayDim = sizeof(T) / sizeof(scalar_type);
+		for (uint32_t i = 1; i < ArrayDim; ++i)
+			retval = retval + getter(lhs, i) * getter(rhs, i);
+
+		return retval;
+	}
+};
+
+#define DEFINE_BUILTIN_VECTOR_SPECIALIZATION(FLOAT_TYPE, RETURN_VALUE)\
+template<uint32_t N>\
+struct dot_helper<vector<FLOAT_TYPE, N> >\
+{\
+	using VectorType = vector<FLOAT_TYPE, N>;\
+	using ScalarType = typename vector_traits<VectorType>::scalar_type;\
+\
+	static inline ScalarType dot(NBL_CONST_REF_ARG(VectorType) lhs, NBL_CONST_REF_ARG(VectorType) rhs)\
+	{\
+		return RETURN_VALUE;\
+	}\
+};\
+
+#ifdef __HLSL_VERSION
+#define BUILTIN_VECTOR_SPECIALIZATION_RET_VAL dot(lhs, rhs)
+#else
+#define BUILTIN_VECTOR_SPECIALIZATION_RET_VAL glm::dot(lhs, rhs)
+#endif
+
+DEFINE_BUILTIN_VECTOR_SPECIALIZATION(float16_t, BUILTIN_VECTOR_SPECIALIZATION_RET_VAL)
+DEFINE_BUILTIN_VECTOR_SPECIALIZATION(float32_t, BUILTIN_VECTOR_SPECIALIZATION_RET_VAL)
+DEFINE_BUILTIN_VECTOR_SPECIALIZATION(float64_t, BUILTIN_VECTOR_SPECIALIZATION_RET_VAL)
+
+#undef BUILTIN_VECTOR_SPECIALIZATION_RET_VAL
+#undef DEFINE_BUILTIN_VECTOR_SPECIALIZATION
+
+#ifdef __HLSL_VERSION
+template<typename Integer>
+struct find_msb_helper;
+#else
+// legacy code wouldn't work without it
+template<typename Integer>
+struct find_msb_helper
+{
+	static int findMSB(NBL_CONST_REF_ARG(Integer) val)
+	{
+		if (is_signed_v<Integer>)
+		{
+			// GLM accepts only integer types, so idea is to cast input to integer type
+			using as_int = typename integer_of_size<sizeof(Integer)>::type;
+			const as_int valAsInt = reinterpret_cast<const as_int&>(val);
+			return glm::findMSB(valAsInt);
+		}
+		else
+		{
+			// GLM accepts only integer types, so idea is to cast input to integer type
+			using as_uint = typename unsigned_integer_of_size<sizeof(Integer)>::type;
+			const as_uint valAsUnsignedInt = reinterpret_cast<const as_uint&>(val);
+			return glm::findMSB(valAsUnsignedInt);
+		}
+	}
+};
+#endif
+
+template<>
+struct find_msb_helper<uint32_t>
+{
+	static int32_t findMSB(NBL_CONST_REF_ARG(uint32_t) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findUMsb(val);
+#else
+		return glm::findMSB(val);
+#endif
+	}
+};
+
+template<>
+struct find_msb_helper<int32_t>
+{
+	static int32_t findMSB(NBL_CONST_REF_ARG(int32_t) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findSMsb(val);
+#else
+		return glm::findMSB(val);
+#endif
+	}
+};
+
+template<int N>
+struct find_msb_helper<vector<uint32_t, N> >
+{
+	static vector<int32_t, N> findMSB(NBL_CONST_REF_ARG(vector<uint32_t, N>) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findUMsb(val);
+#else
+		return glm::findMSB(val);
+#endif
+	}
+};
+
+template<int N>
+struct find_msb_helper<vector<int32_t, N> >
+{
+	static vector<int32_t, N> findMSB(NBL_CONST_REF_ARG(vector<int32_t, N>) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findSMsb(val);
+#else
+		return glm::findMSB(val);
+#endif
+	}
+};
+
+#ifdef __HLSL_VERSION
+template<typename Integer>
+struct find_lsb_helper;
+#else
+// legacy code wouldn't work without it
+template<typename Integer>
+struct find_lsb_helper
+{
+	static int32_t findLSB(NBL_CONST_REF_ARG(Integer) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findILsb(val);
+#else
+		if (is_signed_v<Integer>)
+		{
+			// GLM accepts only integer types, so idea is to cast input to integer type
+			using as_int = typename integer_of_size<sizeof(Integer)>::type;
+			const as_int valAsInt = reinterpret_cast<const as_int&>(val);
+			return glm::findLSB(valAsInt);
+		}
+		else
+		{
+			// GLM accepts only integer types, so idea is to cast input to integer type
+			using as_uint = typename unsigned_integer_of_size<sizeof(Integer)>::type;
+			const as_uint valAsUnsignedInt = reinterpret_cast<const as_uint&>(val);
+			return glm::findLSB(valAsUnsignedInt);
+		}
+#endif
+	}
+};
+#endif
+
+template<>
+struct find_lsb_helper<int32_t>
+{
+	static int32_t findLSB(NBL_CONST_REF_ARG(int32_t) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findILsb(val);
+#else
+		return glm::findLSB(val);
+#endif
+	}
+};
+
+template<>
+struct find_lsb_helper<uint32_t>
+{
+	static int32_t findLSB(NBL_CONST_REF_ARG(uint32_t) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findILsb(val);
+#else
+		return glm::findLSB(val);
+#endif
+	}
+};
+
+template<int N>
+struct find_lsb_helper<vector<int32_t, N> >
+{
+	static vector<int32_t, N> findLSB(NBL_CONST_REF_ARG(vector<int32_t, N>) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findILsb(val);
+#else
+		return glm::findLSB(val);
+#endif
+	}
+};
+
+template<int N>
+struct find_lsb_helper<vector<uint32_t, N> >
+{
+	static vector<int32_t, N> findLSB(NBL_CONST_REF_ARG(vector<uint32_t, N>) val)
+	{
+#ifdef __HLSL_VERSION
+		return spirv::findILsb(val);
+#else
+		return glm::findLSB(val);
+#endif
+	}
+};
+
+template<typename Integer>
+struct find_msb_return_type
+{
+	using type = int32_t;
+};
+template<typename Integer, int N>
+struct find_msb_return_type<vector<Integer, N> >
+{
+	using type = vector<int32_t, N>;
+};
+template<typename Integer>
+using find_lsb_return_type = find_msb_return_type<Integer>;
+
+template<typename T, typename U>
+struct lerp_helper;
+
+#ifdef __HLSL_VERSION
+#define MIX_FUNCTION spirv::fMix
+#else
+#define MIX_FUNCTION glm::mix
+#endif
+
+#define DEFINE_LERP_HELPER_COMMON_SPECIALIZATION(TYPE)\
+template<>\
+struct lerp_helper<TYPE, TYPE>\
+{\
+	static inline TYPE lerp(NBL_CONST_REF_ARG(TYPE) x, NBL_CONST_REF_ARG(TYPE) y, NBL_CONST_REF_ARG(TYPE) a)\
+	{\
+		return MIX_FUNCTION(x, y, a);\
+	}\
+};\
+\
+template<int N>\
+struct lerp_helper<vector<TYPE, N>, vector<TYPE, N> >\
+{\
+	static inline vector<TYPE, N> lerp(NBL_CONST_REF_ARG(vector<TYPE, N>) x, NBL_CONST_REF_ARG(vector<TYPE, N>) y, NBL_CONST_REF_ARG(vector<TYPE, N>) a)\
+	{\
+		return MIX_FUNCTION(x, y, a);\
+	}\
+};\
+\
+template<int N>\
+struct lerp_helper<vector<TYPE, N>, TYPE>\
+{\
+	static inline vector<TYPE, N> lerp(NBL_CONST_REF_ARG(vector<TYPE, N>) x, NBL_CONST_REF_ARG(vector<TYPE, N>) y, NBL_CONST_REF_ARG(TYPE) a)\
+	{\
+		return MIX_FUNCTION(x, y, a);\
+	}\
+};\
+
+DEFINE_LERP_HELPER_COMMON_SPECIALIZATION(float32_t)
+DEFINE_LERP_HELPER_COMMON_SPECIALIZATION(float64_t)
+
+#undef DEFINE_LERP_HELPER_COMMON_SPECIALIZATION
+#undef MIX_FUNCTION
+
+template<typename T>
+struct lerp_helper<T, bool>
+{
+	static inline T lerp(NBL_CONST_REF_ARG(T) x, NBL_CONST_REF_ARG(T) y, NBL_CONST_REF_ARG(bool) a)
+	{
+		return a ? y : x;
+	}
+};
+
+template<typename T, int N>
+struct lerp_helper<vector<T, N>, vector<bool, N> >
+{
+	using output_vec_t = vector<T, N>;
+
+	static inline output_vec_t lerp(NBL_CONST_REF_ARG(output_vec_t) x, NBL_CONST_REF_ARG(output_vec_t) y, NBL_CONST_REF_ARG(vector<bool, N>) a)
+	{
+		output_vec_t retval;
+		for (uint32_t i = 0; i < vector_traits<output_vec_t>::Dimension; i++)
+			retval[i] = a[i] ? y[i] : x[i];
+		return retval;
+	}
+};
+
+}
+}
+}
+
+#endif