基于图象空间的加速体投射算法

Fasting Ray-Casting Algorithm Based on Image

传统的光线投射算法通过视变换将数据体转换到视坐标系下,在视坐标下进行重采样。一方面对于较大的数据体,视变换相当耗时;另一方面,在视坐标下进行重采样,对数据的索引查找较麻烦。基于此,提出了一种新的加速光线投射算法,基于图象空间逆视变换的体绘制算法。该算法在物体坐标系中进行重采样,并利用多边形扫描转换减少了对无效像素的计算。借助视线的参数化方程减少对空体元的采样,从而使得绘制速度基本可以达到实时绘制。

This paper main discusses the idea of the reverse-view transform in the volume-rendering based on image, presents a new fasting ray-casting algorithm. For the more ,this algorithm avoids calculation for useless pixels by polygon scan convertion, at the same time ,it avoids resampling in empty voxels. As the result ,this algorithm improves the whole efficiency of volume -rendering.