def METHOD_NAME(self):
    """Create a 4x4 homography matrix that represents the rotation
    of the quaternion.
    """
    # Init matrix (remember, a matrix, not an array)
    a = np.zeros((4, 4), dtype=np.float32)
    w, x, y, z = self.w, self.x, self.y, self.z
    # First row
    a[0, 0] = - 2.0 * (y * y + z * z) + 1.0
    a[1, 0] = + 2.0 * (x * y + z * w)
    a[2, 0] = + 2.0 * (x * z - y * w)
    a[3, 0] = 0.0
    # Second row
    a[0, 1] = + 2.0 * (x * y - z * w)
    a[1, 1] = - 2.0 * (x * x + z * z) + 1.0
    a[2, 1] = + 2.0 * (z * y + x * w)
    a[3, 1] = 0.0
    # Third row
    a[0, 2] = + 2.0 * (x * z + y * w)
    a[1, 2] = + 2.0 * (y * z - x * w)
    a[2, 2] = - 2.0 * (x * x + y * y) + 1.0
    a[3, 2] = 0.0
    # Fourth row
    a[0, 3] = 0.0
    a[1, 3] = 0.0
    a[2, 3] = 0.0
    a[3, 3] = 1.0
    return a