Add FieldOffsets class

2020-08-04 01:33:52 +02:00 · 2020-08-04 01:33:52 +02:00 · 7fd3264d08
parent 7736312c2f
commit 7fd3264d08
4 changed files with 356 additions and 0 deletions
--- a/include/Nazara/Utility/Enums.hpp
+++ b/include/Nazara/Utility/Enums.hpp
@ -309,6 +309,40 @@ namespace Nz
 		SamplerWrap_Max = SamplerWrap_Repeat
 	};

+	enum StructFieldType
+	{
+		StructFieldType_Bool1,
+		StructFieldType_Bool2,
+		StructFieldType_Bool3,
+		StructFieldType_Bool4,
+		StructFieldType_Float1,
+		StructFieldType_Float2,
+		StructFieldType_Float3,
+		StructFieldType_Float4,
+		StructFieldType_Double1,
+		StructFieldType_Double2,
+		StructFieldType_Double3,
+		StructFieldType_Double4,
+		StructFieldType_Int1,
+		StructFieldType_Int2,
+		StructFieldType_Int3,
+		StructFieldType_Int4,
+		StructFieldType_UInt1,
+		StructFieldType_UInt2,
+		StructFieldType_UInt3,
+		StructFieldType_UInt4,
+
+		StructFieldType_Max = StructFieldType_UInt4
+	};
+
+	enum StructLayout
+	{
+		StructLayout_Packed,
+		StructLayout_Std140,
+
+		StructLayout_Max = StructLayout_Std140
+	};
+
 	enum StencilOperation
 	{
 		StencilOperation_Decrement,
--- a/include/Nazara/Utility/FieldOffsets.hpp
+++ b/include/Nazara/Utility/FieldOffsets.hpp
@ -0,0 +1,52 @@
+// Copyright (C) 2019 Jérôme Leclercq
+// This file is part of the "Nazara Engine - Utility module"
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#pragma once
+
+#ifndef NAZARA_FIELDOFFSETS_HPP
+#define NAZARA_FIELDOFFSETS_HPP
+
+#include <Nazara/Utility/Config.hpp>
+#include <Nazara/Utility/Enums.hpp>
+
+namespace Nz
+{
+	class NAZARA_UTILITY_API FieldOffsets
+	{
+		public:
+			inline FieldOffsets(StructLayout layout);
+			FieldOffsets(const FieldOffsets&) = default;
+			FieldOffsets(FieldOffsets&&) = default;
+			~FieldOffsets() = default;
+
+			std::size_t AddField(StructFieldType type);
+			std::size_t AddFieldArray(StructFieldType type, std::size_t arraySize);
+			std::size_t AddMatrix(StructFieldType cellType, unsigned int columns, unsigned int rows, bool columnMajor);
+			std::size_t AddMatrixArray(StructFieldType cellType, unsigned int columns, unsigned int rows, bool columnMajor, std::size_t arraySize);
+			std::size_t AddStruct(const FieldOffsets& fieldStruct);
+			std::size_t AddStructArray(const FieldOffsets& fieldStruct, std::size_t arraySize);
+
+			inline std::size_t GetLargestFieldAlignement() const;
+			inline std::size_t GetSize() const;
+
+			FieldOffsets& operator=(const FieldOffsets&) = default;
+			FieldOffsets& operator=(FieldOffsets&&) = default;
+
+			static std::size_t GetAlignement(StructLayout layout, StructFieldType fieldType);
+			static std::size_t GetCount(StructFieldType fieldType);
+			static std::size_t GetSize(StructFieldType fieldType);
+
+		private:
+			static inline std::size_t Align(std::size_t source, std::size_t alignment);
+
+			std::size_t m_largestFieldAlignment;
+			std::size_t m_offsetRounding;
+			std::size_t m_size;
+			StructLayout m_layout;
+	};
+}
+
+#include <Nazara/Utility/FieldOffsets.inl>
+
+#endif // NAZARA_FIELDOFFSETS_HPP
--- a/include/Nazara/Utility/FieldOffsets.inl
+++ b/include/Nazara/Utility/FieldOffsets.inl
@ -0,0 +1,169 @@
+// Copyright (C) 2019 Jérôme Leclercq
+// This file is part of the "Nazara Engine - Utility module"
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#include <Nazara/Utility/FieldOffsets.hpp>
+#include <cassert>
+#include <memory>
+#include <Nazara/Utility/Debug.hpp>
+
+namespace Nz
+{
+	inline FieldOffsets::FieldOffsets(StructLayout layout) :
+	m_largestFieldAlignment(1),
+	m_offsetRounding(1),
+	m_size(0),
+	m_layout(layout)
+	{
+	}
+
+	inline std::size_t FieldOffsets::GetLargestFieldAlignement() const
+	{
+		return m_largestFieldAlignment;
+	}
+
+	inline std::size_t FieldOffsets::GetSize() const
+	{
+		return m_size;
+	}
+
+	inline std::size_t FieldOffsets::GetAlignement(StructLayout layout, StructFieldType fieldType)
+	{
+		switch (layout)
+		{
+			case StructLayout_Packed:
+				return 1;
+
+			case StructLayout_Std140:
+			{
+				switch (fieldType)
+				{
+					case StructFieldType_Bool1:
+					case StructFieldType_Float1:
+					case StructFieldType_Int1:
+					case StructFieldType_UInt1:
+						return 4;
+
+					case StructFieldType_Bool2:
+					case StructFieldType_Float2:
+					case StructFieldType_Int2:
+					case StructFieldType_UInt2:
+						return 2 * 4;
+
+					case StructFieldType_Bool3:
+					case StructFieldType_Float3:
+					case StructFieldType_Int3:
+					case StructFieldType_UInt3:
+					case StructFieldType_Bool4:
+					case StructFieldType_Float4:
+					case StructFieldType_Int4:
+					case StructFieldType_UInt4:
+						return 4 * 4;
+
+					case StructFieldType_Double1:
+						return 8;
+
+					case StructFieldType_Double2:
+						return 2 * 8;
+
+					case StructFieldType_Double3:
+					case StructFieldType_Double4:
+						return 4 * 8;
+				}
+			}
+		}
+
+		return 0;
+	}
+
+	inline std::size_t FieldOffsets::GetCount(StructFieldType fieldType)
+	{
+		switch (fieldType)
+		{
+			case StructFieldType_Bool1:
+			case StructFieldType_Double1:
+			case StructFieldType_Float1:
+			case StructFieldType_Int1:
+			case StructFieldType_UInt1:
+				return 1;
+
+			case StructFieldType_Bool2:
+			case StructFieldType_Double2:
+			case StructFieldType_Float2:
+			case StructFieldType_Int2:
+			case StructFieldType_UInt2:
+				return 2;
+
+			case StructFieldType_Bool3:
+			case StructFieldType_Double3:
+			case StructFieldType_Float3:
+			case StructFieldType_Int3:
+			case StructFieldType_UInt3:
+				return 3;
+
+			case StructFieldType_Bool4:
+			case StructFieldType_Double4:
+			case StructFieldType_Float4:
+			case StructFieldType_Int4:
+			case StructFieldType_UInt4:
+				return 4;
+		}
+
+		return 0;
+	}
+
+	inline std::size_t FieldOffsets::GetSize(StructFieldType fieldType)
+	{
+		switch (fieldType)
+		{
+			case StructFieldType_Bool1:
+			case StructFieldType_Float1:
+			case StructFieldType_Int1:
+			case StructFieldType_UInt1:
+				return 4;
+
+			case StructFieldType_Bool2:
+			case StructFieldType_Float2:
+			case StructFieldType_Int2:
+			case StructFieldType_UInt2:
+				return 2 * 4;
+
+			case StructFieldType_Bool3:
+			case StructFieldType_Float3:
+			case StructFieldType_Int3:
+			case StructFieldType_UInt3:
+				return 3 * 4;
+
+			case StructFieldType_Bool4:
+			case StructFieldType_Float4:
+			case StructFieldType_Int4:
+			case StructFieldType_UInt4:
+				return 4 * 4;
+
+			case StructFieldType_Double1:
+				return 8;
+
+			case StructFieldType_Double2:
+				return 2 * 8;
+
+			case StructFieldType_Double3:
+				return 3 * 8;
+
+			case StructFieldType_Double4:
+				return 4 * 8;
+		}
+
+		return 0;
+	}
+
+	inline std::size_t FieldOffsets::Align(std::size_t source, std::size_t alignment)
+	{
+		if (source == 0)
+			return source;
+
+		assert(alignment > 0);
+		return ((source + alignment - 1) / alignment) * alignment;
+	}
+}
+
+#include <Nazara/Utility/DebugOff.hpp>
--- a/src/Nazara/Utility/FieldOffsets.cpp
+++ b/src/Nazara/Utility/FieldOffsets.cpp
@ -0,0 +1,101 @@
+// Copyright (C) 2019 Jérôme Leclercq
+// This file is part of the "Nazara Engine - Utility module"
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#include <Nazara/Utility/FieldOffsets.hpp>
+#include <algorithm>
+#include <cassert>
+#include <Nazara/Utility/Debug.hpp>
+
+namespace Nz
+{
+	std::size_t FieldOffsets::AddField(StructFieldType type)
+	{
+		std::size_t fieldAlignement = GetAlignement(m_layout, type);
+
+		m_largestFieldAlignment = std::max(m_largestFieldAlignment, fieldAlignement);
+
+		std::size_t offset = Align(m_size, Align(fieldAlignement, m_offsetRounding));
+		m_size = offset + GetSize(type);
+
+		m_offsetRounding = 1;
+
+		return offset;
+	}
+
+	std::size_t FieldOffsets::AddFieldArray(StructFieldType type, std::size_t arraySize)
+	{
+		std::size_t fieldAlignement = GetAlignement(m_layout, type);
+		if (m_layout == StructLayout_Std140)
+			fieldAlignement = Align(fieldAlignement, GetAlignement(StructLayout_Std140, StructFieldType_Float4));
+
+		m_largestFieldAlignment = std::max(fieldAlignement, m_largestFieldAlignment);
+
+		std::size_t offset = Align(m_size, Align(fieldAlignement, m_offsetRounding));
+		m_size = offset + GetSize(type) * arraySize;
+
+		m_offsetRounding = 1;
+
+		return offset;
+	}
+
+	std::size_t FieldOffsets::AddMatrix(StructFieldType cellType, unsigned int columns, unsigned int rows, bool columnMajor)
+	{
+		assert(GetCount(cellType) == 1);
+		assert(columns >= 2 && columns <= 4);
+		assert(rows >= 2 && rows <= 4);
+
+		if (columnMajor)
+			return AddFieldArray(static_cast<StructFieldType>(cellType + rows - 1), columns);
+		else
+			return AddFieldArray(static_cast<StructFieldType>(cellType + columns - 1), rows);
+	}
+
+	std::size_t FieldOffsets::AddMatrixArray(StructFieldType cellType, unsigned int columns, unsigned int rows, bool columnMajor, std::size_t arraySize)
+	{
+		assert(GetCount(cellType) == 1);
+		assert(columns >= 2 && columns <= 4);
+		assert(rows >= 2 && rows <= 4);
+
+		if (columnMajor)
+			return AddFieldArray(static_cast<StructFieldType>(cellType + rows - 1), columns * arraySize);
+		else
+			return AddFieldArray(static_cast<StructFieldType>(cellType + columns - 1), rows * arraySize);
+	}
+
+	std::size_t FieldOffsets::AddStruct(const FieldOffsets& fieldStruct)
+	{
+		std::size_t fieldAlignement = fieldStruct.GetLargestFieldAlignement();
+		if (m_layout == StructLayout_Std140)
+			fieldAlignement = Align(fieldAlignement, GetAlignement(StructLayout_Std140, StructFieldType_Float4));
+
+		m_largestFieldAlignment = std::max(m_largestFieldAlignment, fieldAlignement);
+
+		std::size_t offset = Align(m_size, Align(fieldAlignement, m_offsetRounding));
+		m_size = offset + fieldStruct.GetSize();
+
+		m_offsetRounding = std::max<std::size_t>(Align(fieldStruct.GetSize(), fieldAlignement) - fieldStruct.GetSize(), 1);
+
+		return offset;
+	}
+
+	std::size_t FieldOffsets::AddStructArray(const FieldOffsets& fieldStruct, std::size_t arraySize)
+	{
+		assert(arraySize > 0);
+
+		std::size_t fieldAlignement = fieldStruct.GetLargestFieldAlignement();
+		if (m_layout == StructLayout_Std140)
+			fieldAlignement = Align(fieldAlignement, GetAlignement(StructLayout_Std140, StructFieldType_Float4));
+
+		m_largestFieldAlignment = std::max(m_largestFieldAlignment, fieldAlignement);
+
+		std::size_t offset = Align(m_size, Align(fieldAlignement, m_offsetRounding));
+		m_size = offset
+		       + fieldStruct.GetSize() * arraySize
+		       + (Align(fieldStruct.GetSize(), fieldAlignement) - fieldStruct.GetSize()) * (arraySize - 1);
+
+		m_offsetRounding = fieldAlignement;
+
+		return offset;
+	}
+}