平面投射多分辨率软阴影绘制算法

A SOFT SHADOW RENDERING ALGORITHM OF PLANAR PROJECTION AND MULTI-RESOLUTION

阴影生成技术在计算机真实感图形应用中发挥着独特而重要的作用。基于模板缓存技术、图像融合技术及反走样技术等,提出一种多分辨率多平面投射软阴影绘制方法。该方法首先通过在光源上进行离散采样,获得一组硬阴影绘制图像;再通过颜色混合和模板缓存技术对这组图像进行平均化处理,合成得到软阴影图像;最后利用累加缓存对场景进行反走样处理,使软阴影绘制效果更加自然、柔和。该方法提供了绘制精度的参数控制手段,使用户可以交互地设定生成软阴影的分辨率。

Shadow generation technique plays a unique and important role in computer realistic graphics applications.In this paper,the allthors present a special algorithm for rendering shadows with multi-resolution on a set of specific planes based on the technologies of pattern buffer,image blending and anti-aliasing.In the algorithm,a set of hard shadow rendering images are obtained through discrete sampling on given domain light source firstly.The colour blending technology and pattern buffer technology are employed to average the set of images and to get soft shadow images by synthesisation.Finally,the accumulation buffer technology is also used to process the scenes for anti-aliasing to make the rendering effect of soft shadows more natural and gentle.Our method provides a way in controlling the rendering precision parameter and enables the user to interactively set the resolution for generating soft shadows.