cam_pos      = [-0.277167, 1.45959, 0.617463]';
cam_dir      = [-0.867971, 0.0809324, -0.489975]';
cam_up       = [0.4816, 0.377945, -0.790708]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.161183, 1.22664, 0.488141]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;