add maths utils

include/misc/Maths.h

@@ -0,0 +1,113 @@
+#pragma once
+
+#include "Defines.h"
+#include <cmath>
+
+namespace td {
+namespace maths {
+
+//////////////////////////////////////////////////////////////////
+// 							Vectors								//
+//////////////////////////////////////////////////////////////////
+
+template<typename T>
+Vec3<T> operator- (const Vec3<T>& vect) {
+	return { -vect.x, -vect.y, -vect.z };
+}
+
+template<typename T>
+Vec3<T> operator+ (const Vec3<T>& vect, const Vec3<T>& other) {
+	return { vect.x + other.x, vect.y + other.y, vect.z + other.y };
+}
+
+template<typename T>
+Vec3<T> operator- (const Vec3<T>& vect, const Vec3<T>& other) {
+	return vect + (-other);
+}
+
+template<typename T>
+Vec3<T> Normalize(const Vec3<T>& vect) {
+	T length = std::sqrt(vect.x * vect.x + vect.y * vect.y + vect.z * vect.z);
+
+	return { vect.x / length, vect.y / length, vect.z / length };
+}
+
+template<typename T>
+T Dot(const Vec3<T>& vect, const Vec3<T>& other) {
+	return vect.x * other.x + vect.y * other.y + vect.z * other.z;
+}
+
+template<typename T>
+Vec3<T> Cross(const Vec3<T>& vect, const Vec3<T>& other) {
+	return {
+		vect.y * other.z - vect.z * other.y,
+		vect.z * other.x - vect.x * other.z,
+		vect.x * other.y - vect.y * other.x,
+	};
+}
+
+
+
+//////////////////////////////////////////////////////////////////
+// 						    Matricies							//
+//////////////////////////////////////////////////////////////////
+
+template<typename T>
+struct Mat4 {
+	T x0, x1, x2, x3;
+	T y0, y1, y2, y3;
+	T z0, z1, z2, z3;
+	T w0, w1, w2, w3;
+
+	T operator[] (std::size_t offset) const {
+		return reinterpret_cast<const T*>(this)[offset];
+	}
+
+	T& operator[] (std::size_t offset) {
+		return reinterpret_cast<T*>(this)[offset];
+	}
+};
+
+typedef Mat4<float> Mat4f;
+typedef Mat4<int> Mat4i;
+typedef Mat4<double> Mat4d;
+
+Mat4f Perspective(float fovY, float aspectRatio, float zNear, float zFar);
+Mat4f LookAt(const Vec3f& eye, const Vec3f& center, const Vec3f& up);
+
+Mat4f Dot(const Mat4f& mat, const Mat4f& other);
+
+template<typename T>
+Mat4<T> Identity() {
+	Mat4<T> result{};
+
+	result.x0 = static_cast<T>(1);
+	result.y1 = static_cast<T>(1);
+	result.z2 = static_cast<T>(1);
+	result.w3 = static_cast<T>(1);
+
+	return result;
+}
+
+template<typename T>
+Mat4<T> Transpose(const Mat4<T>& mat) {
+	Mat4<T> result;
+
+	result.x1 = mat.y0;
+	result.x2 = mat.z0;
+	result.x3 = mat.w0;
+	result.y0 = mat.x1;
+	result.y2 = mat.z1;
+	result.y3 = mat.w1;
+	result.z0 = mat.x2;
+	result.z1 = mat.y2;
+	result.z3 = mat.w2;
+	result.w0 = mat.x3;
+	result.w1 = mat.y3;
+	result.w2 = mat.z3;
+
+	return result;
+}
+
+} // namespace maths
+} // namespace td