Initial commit

source/Math/Math.cpp

@@ -0,0 +1,99 @@
+
+#include <cstdlib>
+#include <Spectre/Math/Math.h>
+
+namespace math {
+
+	float rand(float min, float max) {
+
+		float r = ((float) ::rand()) / RAND_MAX;
+		return ((max - min) * r) + min;
+	}
+
+	float deg2rad(float deg) {
+
+		return deg * 3.141592654f / 180.0f;
+	}
+
+	unsigned int nextPowerOfTwo(unsigned int value) {
+
+		if (value == 0) {
+			return 1;
+		}
+
+		unsigned int exp = static_cast<unsigned int>(::ceil(log2(value)));
+		return ::pow(2.0f, exp);
+	}
+
+	// left, right, bottom, top, near, far.
+
+	Matrix4f orthoProjection(float left, float right,
+		float bottom, float top,
+		float zNear, float zFar) {
+
+		float	rl = (right - left), 
+			tb = (top - bottom),
+			fn = (zFar - zNear),
+			rl2 = 2.0f / rl,
+			tb2 = 2.0f / tb,
+			fn2 = 2.0f / fn,
+			x = (right + left) / rl,
+			y = (top + bottom) / tb,
+			z = (zFar + zNear) / fn;
+
+		return Matrix4f(
+			rl2 , 0.0f,  0.0f, -x,
+			0.0f, tb2 ,  0.0f, -y,
+			0.0f, 0.0f,  -fn2, -z,
+			0.0f, 0.0f,  0.0f, 1.0f
+		);
+	}
+
+	Matrix4f rotation(float theta) {
+
+		float r = deg2rad(theta);
+		float s = std::sin(r);
+		float c = std::cos(r);
+
+		return Matrix4f(
+			   c,   -s, 0.0f, 0.0f,
+			   s,    c, 0.0f, 0.0f,
+			0.0f, 0.0f, 1.0f, 0.0f,
+			0.0f, 0.0f, 0.0f, 1.0f);
+	}
+
+	Matrix4f translate(const Vector2f& v) {
+
+		return Matrix4f(
+			1.0f, 0.0f, 0.0f, v.x,
+			0.0f, 1.0f, 0.0f, v.y,
+			0.0f, 0.0f, 1.0f, 0.0f,
+			0.0f, 0.0f, 0.0f, 1.0f);
+
+	}
+
+	Matrix4f scale(const Vector2f& f) {
+
+		return Matrix4f(
+			f.x , 0.0f, 0.0f, 0.0f,
+			0.0f, f.y , 0.0f, 0.0f,
+			0.0f, 0.0f, 1.0f, 0.0f,
+			0.0f, 0.0f, 0.0f, 1.0f);
+	}
+
+	Vector3f getTranslate(const Matrix4f matrix) {
+
+		return Vector3f(matrix.e[12], matrix.e[13], matrix.e[14]);
+	}
+
+
+	Vector3f getUpVector(const Matrix4f matrix) {
+
+		return Vector3f(matrix.e[4], matrix.e[5], matrix.e[6]);
+	}
+
+	Vector3f getForwardVector(const Matrix4f matrix) {
+
+		return Vector3f(matrix.e[8], matrix.e[9], matrix.e[10]);
+	}
+};