cam_pos      = [0.446854, 1.27205, -0.469308]';
cam_dir      = [-0.960851, -0.27467, -0.0363519]';
cam_up       = [-0.272879, 0.960874, -0.0475141]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.0638138, 0.0475266, 1.32762]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;