If each scanline has its own layer, the Pole Position effect is produced, which creates a pseudo-3D road (or a pseudo-3D ball court as in NBA Jam) on a 2D system.
如果每条扫描线都有自己的图层，就会产生Pole Position游戏的效果，就是在2D系统中创建一个伪3D的道路（或者NBA Jam游戏中的伪3D球场）。