gistfile1.txt

mat4 LookAt(const vec3& eye, const vec3& target, const vec3& up) {
  vec3 z = (eye - target).Normalized();
  vec3 x = up.Cross(z).Normalized();
  vec3 y = z.Cross(x).Normalized();

  mat4 m;
  m.x = vec4(x, 0);
  m.y = vec4(y, 0);
  m.z = vec4(z, 0);
  m.w = vec4(0,0,0,1);

  vec4 eyePrime = m* -eye;
  m = m.Transposed();
  m.w = eyePrime;

  return m;
}