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diff --git a/src/libmatrix/mat.cc b/src/libmatrix/mat.cc
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+//
+// Copyright (c) 2010 Linaro Limited
+//
+// All rights reserved. This program and the accompanying materials
+// are made available under the terms of the MIT License which accompanies
+// this distribution, and is available at
+// http://www.opensource.org/licenses/mit-license.php
+//
+// Contributors:
+//     Jesse Barker - original implementation.
+//
+#include <math.h>
+#include "mat.h"
+
+namespace LibMatrix
+{
+namespace Mat4
+{
+
+mat4
+translate(float x, float y, float z)
+{
+    mat4 t;
+    t[0][3] = x;
+    t[1][3] = y;
+    t[2][3] = z;
+    return t;
+}
+
+mat4
+scale(float x, float y, float z)
+{
+    mat4 s;
+    s[0][0] = x;
+    s[1][1] = y;
+    s[2][2] = z;
+    return s;
+}
+
+//
+// As per the OpenGL "red book" definition of rotation, from the appendix
+// on Homogeneous Coordinates and Transformation Matrices, the "upper left"
+// 3x3 portion of the result matrix is formed by:
+//
+// M = uuT + (cos a)(I - uuT) + (sin a)S
+//
+// where u is the normalized input vector, uuT is the outer product of that
+// vector and its transpose, I is the identity matrix and S is the matrix:
+//
+// |  0  -z'  y' |
+// |  z'  0  -x' |
+// | -y'  x'  0  |
+//
+// where x', y' and z' are the elements of u
+//
+mat4
+rotate(float angle, float x, float y, float z)
+{
+    vec3 u(x, y, z);
+    u.normalize();
+    mat3 uuT = outer(u, u);
+    mat3 s;   
+    s[0][0] = 0;
+    s[0][1] = -u.z();
+    s[0][2] = u.y();
+    s[1][0] = u.z();
+    s[1][1] = 0;
+    s[1][2] = -u.x();
+    s[2][0] = -u.y();
+    s[2][1] = u.x();
+    s[2][2] = 0;
+    mat3 i;
+    i -= uuT;
+    // degrees to radians
+    float angleRadians(angle * M_PI / 180.0);
+    i *= cos(angleRadians);
+    s *= sin(angleRadians);
+    i += s;
+    mat3 m = uuT + i;
+    mat4 r;
+    r[0][0] = m[0][0];
+    r[0][1] = m[0][1];
+    r[0][2] = m[0][2];
+    r[1][0] = m[1][0];
+    r[1][1] = m[1][1];
+    r[1][2] = m[1][2];
+    r[2][0] = m[2][0];
+    r[2][1] = m[2][1];
+    r[2][2] = m[2][2];
+    return r;
+}
+
+mat4
+frustum(float left, float right, float bottom, float top, float near, float far)
+{
+    float twiceNear(2 * near);
+    float width(right - left);
+    float height(top - bottom);
+    float depth(far - near);
+    mat4 f;
+    f[0][0] = twiceNear / width;
+    f[0][2] = (right + left) / width;
+    f[1][1] = twiceNear / height;
+    f[1][2] = (top + bottom) / height;
+    f[2][2] = -(far + near) / depth;
+    f[2][3] = -(twiceNear * far) / depth;
+    f[3][2] = -1;
+    f[3][3] = 0;
+    return f;
+}
+
+mat4
+ortho(float left, float right, float bottom, float top, float near, float far)
+{
+    float width(right - left);
+    float height(top - bottom);
+    float depth(far - near);
+    mat4 o;
+    o[0][0] = 2 / width;
+    o[0][3] = (right + left) / width;
+    o[1][1] = 2 / height;
+    o[1][3] = (top + bottom) / height;
+    o[2][2] = -2 / depth;
+    o[2][3] = (far + near) / depth;
+    return o;
+}
+
+mat4
+perspective(float fovy, float aspect, float zNear, float zFar)
+{
+    // degrees to radians
+    float fovyRadians(fovy * M_PI / 180.0);
+    // cotangent(x) = 1/tan(x)
+    float f = 1/tan(fovyRadians / 2);
+    float depth(zNear - zFar);
+    mat4 p;
+    p[0][0] = f / aspect;
+    p[1][1] = f;
+    p[2][2] = (zFar + zNear) / depth;
+    p[2][3] = (2 * zFar * zNear) / depth;
+    p[3][2] = -1;
+    p[3][3] = 0;
+    return p;
+}
+
+mat4 lookAt(float eyeX, float eyeY, float eyeZ, 
+    float centerX, float centerY, float centerZ, 
+    float upX, float upY, float upZ)
+{
+    vec3 f(centerX - eyeX, centerY - eyeY, centerZ - eyeZ);
+    f.normalize();
+    vec3 up(upX, upY, upZ);
+    vec3 s = vec3::cross(f, up);
+    vec3 u = vec3::cross(s, f);
+    s.normalize();
+    u.normalize();
+    mat4 la;
+    la[0][0] = s.x();
+    la[0][1] = s.y();
+    la[0][2] = s.z();
+    la[1][0] = u.x();
+    la[1][1] = u.y();
+    la[1][2] = u.z();
+    la[2][0] = -f.x();
+    la[2][1] = -f.y();
+    la[2][2] = -f.z();
+    la *= translate(-eyeX, -eyeY, -eyeZ);
+    return la;
+}
+
+} // namespace Mat4
+
+} // namespace LibMatrix