cam_pos      = [-0.421163, 1.49095, 1.30408]';
cam_dir      = [-0.776583, 0.145402, -0.613006]';
cam_up       = [0.569291, 0.578734, -0.58393]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.358918, 1.06726, 0.707841]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;