Refactor

apps/LoopThroughWithOpenGLCompositing/gl/Std140Buffer.h

@@ -0,0 +1,48 @@
+#pragma once
+
+#include <cstddef>
+#include <cstring>
+#include <vector>
+
+inline std::size_t AlignStd140(std::size_t offset, std::size_t alignment)
+{
+	const std::size_t mask = alignment - 1;
+	return (offset + mask) & ~mask;
+}
+
+template <typename TValue>
+inline void AppendStd140Value(std::vector<unsigned char>& buffer, std::size_t alignment, const TValue& value)
+{
+	const std::size_t offset = AlignStd140(buffer.size(), alignment);
+	if (buffer.size() < offset + sizeof(TValue))
+		buffer.resize(offset + sizeof(TValue), 0);
+	std::memcpy(buffer.data() + offset, &value, sizeof(TValue));
+}
+
+inline void AppendStd140Float(std::vector<unsigned char>& buffer, float value)
+{
+	AppendStd140Value(buffer, 4, value);
+}
+
+inline void AppendStd140Int(std::vector<unsigned char>& buffer, int value)
+{
+	AppendStd140Value(buffer, 4, value);
+}
+
+inline void AppendStd140Vec2(std::vector<unsigned char>& buffer, float x, float y)
+{
+	const std::size_t offset = AlignStd140(buffer.size(), 8);
+	if (buffer.size() < offset + sizeof(float) * 2)
+		buffer.resize(offset + sizeof(float) * 2, 0);
+	float values[2] = { x, y };
+	std::memcpy(buffer.data() + offset, values, sizeof(values));
+}
+
+inline void AppendStd140Vec4(std::vector<unsigned char>& buffer, float x, float y, float z, float w)
+{
+	const std::size_t offset = AlignStd140(buffer.size(), 16);
+	if (buffer.size() < offset + sizeof(float) * 4)
+		buffer.resize(offset + sizeof(float) * 4, 0);
+	float values[4] = { x, y, z, w };
+	std::memcpy(buffer.data() + offset, values, sizeof(values));
+}