1 files changed, 77 insertions, 0 deletions
diff --git a/lib/gl_traits.h b/lib/gl_traits.h
new file mode 100644
index 0000000..6ff8905
--- /dev/null
+++ b/lib/gl_traits.h
@@ -0,0 +1,77 @@
+#pragma once
+
+#include <GL/glew.h>
+#include <array>
+#include <glm/common.hpp>
+#include <glm/fwd.hpp>
+
+template<typename T> struct gl_traits;
+struct gl_traits_base {
+	static constexpr GLint size {1};
+};
+struct gl_traits_float : public gl_traits_base {
+	static constexpr auto vertexAttribFunc {
+			[](GLuint index, GLint size, GLenum type, GLsizei stride, const void * pointer) -> GLuint {
+				glVertexAttribPointer(index, size, type, GL_FALSE, stride, pointer);
+				return 1;
+			}};
+};
+struct gl_traits_longfloat : public gl_traits_base {
+	static constexpr auto vertexAttribFunc {
+			[](GLuint index, GLint size, GLenum type, GLsizei stride, const void * pointer) -> GLuint {
+				glVertexAttribLPointer(index, size, type, stride, pointer);
+				return 1;
+			}};
+};
+struct gl_traits_integer : public gl_traits_base {
+	static constexpr auto vertexAttribFunc {
+			[](GLuint index, GLint size, GLenum type, GLsizei stride, const void * pointer) -> GLuint {
+				glVertexAttribIPointer(index, size, type, stride, pointer);
+				return 1;
+			}};
+};
+template<> struct gl_traits<glm::f32> : public gl_traits_float {
+	static constexpr GLenum type {GL_FLOAT};
+};
+template<> struct gl_traits<glm::f64> : public gl_traits_longfloat {
+	static constexpr GLenum type {GL_DOUBLE};
+};
+template<> struct gl_traits<glm::int8> : public gl_traits_integer {
+	static constexpr GLenum type {GL_BYTE};
+};
+template<> struct gl_traits<glm::int16> : public gl_traits_integer {
+	static constexpr GLenum type {GL_SHORT};
+};
+template<> struct gl_traits<glm::int32> : public gl_traits_integer {
+	static constexpr GLenum type {GL_INT};
+};
+template<> struct gl_traits<glm::uint8> : public gl_traits_integer {
+	static constexpr GLenum type {GL_UNSIGNED_BYTE};
+};
+template<> struct gl_traits<glm::uint16> : public gl_traits_integer {
+	static constexpr GLenum type {GL_UNSIGNED_SHORT};
+};
+template<> struct gl_traits<glm::uint32> : public gl_traits_integer {
+	static constexpr GLenum type {GL_UNSIGNED_INT};
+};
+
+template<typename T, std::size_t S> struct gl_traits<std::array<T, S>> : public gl_traits<T> {
+	static constexpr GLint size {S * gl_traits<T>::size};
+};
+
+template<glm::length_t L, typename T, glm::qualifier Q> struct gl_traits<glm::vec<L, T, Q>> : public gl_traits<T> {
+	static constexpr GLint size {L};
+};
+
+template<glm::length_t C, glm::length_t R, typename T, glm::qualifier Q>
+struct gl_traits<glm::mat<C, R, T, Q>> : public gl_traits<T> {
+	static constexpr GLint size {C * R};
+	static constexpr auto vertexAttribFunc {
+			[](GLuint index, GLint, GLenum type, GLsizei stride, const void * pointer) -> GLuint {
+				const auto base = static_cast<const T *>(pointer);
+				for (GLuint r = 0; r < R; r++) {
+					glVertexAttribPointer(index + r, C, type, GL_FALSE, stride, base + (r * C));
+				}
+				return R;
+			}};
+};