基于线性八叉树的光线投射体绘制算法改进研究

Study of Improvement of Ray Casting Volume Rendering Algorithm Based on Linear Octree Structure

体视化是地学信息三维可视化研究的前沿技术之一 ,体绘制算法的效率直接关系到体视化的效果。本文在研究已有光线投射体绘制改进算法的基础上 ,提出利用线性八叉树数据结构对光线投射体绘制算法进行改进研究 ,不仅实现了体数据的压缩 ,而且能对压缩体数据进行直接体视化。在PC机上的实验表明 ,该方法具有时间复杂度与数据复杂度基本无关的特点 ,加速效果明显。最后 ,文章指出了该方法的适用范围。

Volume visualization is one of the leading technologies of the geo-information 3D visualization. The efficiency of the volume rendering algorithm is directly correlated to the effect of the volume visualization. This paper firstly discusses the existing acceleration algorithm of ray casting volume rendering, then, based on this research work, the authors present a new improvement method which leads the octree structure into ray casting volume rendering algorithm, and realizes not only the compression of volume data, but also the direct visualization of the compressed data. Experiments on PC prove that it has the characteristic that the cost of time has nearly nothing to do with the complexity of data and the effect of acceleration is distinct. At last, the authors point out the beseemed coverage of this method.