面向地震灾害场景建模的三维地形交互改造技术

Interactive Terrain Modification Technology for Earthquake Disaster Scene Modeling

在虚拟地震灾害场景基础上,提出一种细节可控的三维地形实时改造算法,用于模拟因地震造成灾区地表形态的变化情况。该方法将地形改造的主要任务交由GPU(图形处理器)的pixel shader(像素着色器)完成,在pixel shader中将原始地形高度图的高程数据读取出来,通过设计算法对数据进行改造后输出至一张新的高度图,并用新的高度图替换原始高度图重新绘制一遍场景,以完成地形的实时改造;使用"乒乓"算法和批处理方式对地形改造效率进一步优化;引入Perlin(柏林)噪声增加了地形改造结果的随机扰动性,使改造结果更加逼真和接近实际情况。实验结果表明:该方法能够在地震灾害场景仿真平台中得到很好的应用,运算效率高,能够满足地形实时改造和交互编辑的实际需求。

Based on the virtual earthquake disaster scene, We put forward a real-time terrain modification algorithm with controllable details, and use this method to simulate the terrain deformation of disaster area. GPU completes most of the terrain modification computation using pixel shader. Pixel shader reads the raw data from height map and executes the modification, then outputs the results to a new map, which is transferred to main memory and replaces the old data. And then the terrain is rendered again to complete the terrain modification. The algorithm is optimized by using ＂Ping-Pang＂ algorithm and batch processing. Furthermore, Perlin noise is introduced into the modification algorithm to simulate the complicated morphology of terrain surface in disaster scene. The experimental results show that this method obtains a successful application in virtual earthquake scene, and can meet the real- time modification and interactive editing of terrain.