大坝地震反应数据场快速体绘制算法

Quick Volume Rendering for Data of Dam Seismic Response

为了弥补传统体绘制静止画面时 ,不能明确判断场值集中部位的不足 ,提出了一种快速体绘制算法 ,针对大坝地震反应有限元计算数据场 ,根据每个单元法线与视线夹角最小的表面来选择剖切方向 ,将单元剖切成多个四边形面后进行颜色融合和叠加 ,大大提高了体绘制速度 ,实现了动态观察体绘制图 ,从而清楚地分析场值集中部位 .

The concentrative part of field value can't be judged exactly on the static picture of classical volume rendering. In order to remedy this kind of shortage, this paper presents a quick volume rendering method, for the finite element data field of dam seismic response, choices the slicing direction relying on the element surface which normal line has the smallest included angle with the view direction, slices elements to many quadrilaterals, blends the colors of these quadrilaterals by using OpenGL blending technology, and then superimposes all elements one by one. This method accelerates the speed of volume rendering, thus, we can observe dynamic pictures of volume rendering and analyzes the concentrative part of field value clearly.