基于边缘拟合阴影图的实时硬阴影生成

阴影贴图(Shadow Mapping)技术已被广泛应用于3D游戏及其它实时图形应用中.本文针对阴影贴图在渲染场景时阴影边缘出现严重锯齿这一现象,提出一种实时硬阴影的反走样技术,边缘拟合阴影图EFSMs(Edge Fitting Shadow Maps)算法.阴影贴图所引起的透视走样及投影走样,均会导致多个像素对应阴影图(Shadow Map)中的一个纹素,即出现多对一映射;使用EFSMs算法,在进行阴影映射时,得到较为精确的对应纹素,从而避免多对一阴影映射时产生的边缘锯齿.实验结果显示,此方法极大消除了边缘的锯齿现象,其效率相比其它基于阴影贴图的阴影技术得到较大提升.

Real-time hard shadow generation based on edge fitting shadow maps

Shadow Mapping technology has been widely used in 3D games and other graphics applications. Aiming at solving the severe jag of shadow edge when rendering the scene, the paper proposes a kind of real time hard shadows anti aliasing technology, Edge Fitting Shadow Maps(EFSMs). Both perspective aliasing and project aliasing caused by Shadow Mapping lead to many to one mapping phenomenon that a number of pixels correspond to a texel of Shadow Map. EFSMs algorithm, can get more precise corresponding texel, thus it can avoid the edge aliasing. The experimental results show that this method greatly eliminates the edge jag, and its efficiency compared with other Shadow Mapping is much better.