cam_pos      = [0.183516, 1.47428, 0.776696]';
cam_dir      = [0.988036, -0.0166796, -0.153319]';
cam_up       = [-0.137282, 0.357881, -0.923621]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.0934664, -1.24171, -0.467241]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;