Subversion Repositories gelsvn

  /** Compute inverse assuming that the upper-left 3x3 sub-matrix is

      orthonormal (which is the case if the transformation is only

      a concatenation of rotations and translations).

  */

  inline Mat4x4d invert_ortho(const Mat4x4d& m)

  {

    Vec3d rx(m[0][0], m[1][0], m[2][0]);

    Vec3d ry(m[0][1], m[1][1], m[2][1]);

    Vec3d rz(m[0][2], m[1][2], m[2][2]);

    Vec3d t(m[0][3], m[1][3], m[2][3]);

    return Mat4x4d(Vec4d(rx, -dot(t, rx)),

		   Vec4d(ry, -dot(t, ry)),

		   Vec4d(rz, -dot(t, rz)),

		   Vec4d(0.0, 0.0, 0.0, 1.0));

  }