cam_pos      = [0.466723, 1.64796, 0.331273]';
cam_dir      = [0.503653, 0.302961, -0.809041]';
cam_up       = [-0.106977, 0.951156, 0.289582]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-1.14015, 0.0788691, -0.680246]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;