一种基于阴影图的实时软阴影算法

Algorithm of real-time soft shadows based on shadow maps

提出了一种基于阴影图技术的实时软阴影生成算法。首先为场景中遮挡物、接收面计算深度缓存,并离散遮挡物成许多微面;接着计算每个微面的阴影深度值,估计微面的可见度;最后计算微面半影范围,将软阴影图投影回场景中,得到实时软阴影。实验结果表明该算法对复杂物体在保证绘制视觉效果的同时,能达到令人满意的帧速率,从而为更复杂场景的实时软阴影绘制提供了有效的解决途径。

A new algorithm of real-time soft shadows based on shadow maps was presented. Fimtly, we generated two depth buffers for occluder and receiver, discretizing the occluder to micro-patches; then, we calculated the depth value of shadow for each micro-patch and estimated the visibilities of them; finally, we computed penumbra extent for each micro-patch and projected soft shadow map on the scene to obtain real-time soft shadows. Experiments demonstrate that the algorithm can provide visually pleasing effect for the complex objects and achieve satisfying frame rate at the same time, Therefore, we offered an effective way to generate real-time soft shadow for the complex scenes.