cam_pos      = [0.698379, 1.64486, 0.327699]';
cam_dir      = [-0.418947, -0.396763, -0.816739]';
cam_up       = [-0.0430047, 0.907142, -0.418621]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-1.2063, 0.186542, 0.528152]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;