八叉树空间结构投影的射线物体求交方法

A ray intersection method based on octree spatial structure's projection

为了提高光线投射算法中射线与物体求交速度,提出一种利用八叉树空间结构在视平面上投影的射线快速求交方法。算法构造平行于视平面的八叉树空间结构,将每个八叉树叶子包围盒沿视点方向投影在视平面上,将视平面划分成若干投影区域。在射线与包围盒求交时,根据射线落在视平面上的位置,确定其所属投影区域,求出与该射线相交的包围盒。实验表明该算法对传统的光线投射算法效率有较大提升。

In order to improve ray intersection with the object speed in ray casting. Proposed a fast ray inter- section method using octree spatial structure＇s projection on the viewing plane. Constructed an oetree spatial structure parallel to the viewing plane, then project octree leaves＇ bounding volume along the viewing direction to the viewing plane, viewing plane is divided into lots of blocks of the projection area. In the ray intersection with the bounding volume, the ray falls on the viewing plane, determining its respective projection area, and then finding the ray intersects the bounding volume. Experimental results show that the algorithm can speed up the efficiency of the ray intersection compared with the traditional method.