Eecoding speed of our current approach is essential and it is proved to be efficient . texture pyramid can be used for anti - aliasing . high - quality shading is often realized by pre - shadi 目前，地形shading时通常对几何模型预先计算，并把结果存储为纹理图象进行绘制，而动态光源的地形shading仍是个问题。
