ABSTRACT
This chapter describes novel techniques that extend the original screen-space soft shadows (SSSS) algorithm in order to make sure that the speed of rendering is optimal and and taken into consideration overlapping and translucent shadows. It introduces layers, an essential component to filtering overlapping shadows in screen space. The chapter renders near one hundred properly filtered, perceptually correct shadows in real time, and makes this technique easy to integrate into existing rendering pipelines. The screen-space techniques are beneficial because they come with a constant filtering cost, so one does not need to filter the shadows per light source, but the whole screen. Therefore, lights and shadow map filtering are decoupled, and one can employ huge filter kernels resulting in cheap, large penumbras. There are various ways to speed up the SSSS rendering process.
