基于三角形分解的三角网切割  

Triangular Mesh Clipping Using Triangular Decomposition

作　　者：陈国军[1] 黄莹莹 李华[2] 李金玲 刘婧怡 

机构地区：[1]中国石油大学(华东)计算机与通信工程学院,青岛266580 [2]中国石油天然气股份有限公司勘探开发研究院,北京100083

出　　处：《系统仿真学报》2017年第11期2656-2662,共7页Journal of System Simulation

基　　金：国家863计划(2015AA016403);虚拟现实技术与系统国家重点实验室(北京航空航天大学)开放基金(BUAA-VR-15KF-13);山东省教育厅高校科技计划(J15LN66)

摘　　要：三角网的切割广泛应用于网格重构、网格变形、地形融合与分析等领域,在地理信息系统应用中,三角网切割是实现地形表面模型与建筑物模型融合的关键算法。现有的多边形裁剪算法没有考虑相邻三角形的空间关系,直接用于切割三角网往往会出现T交叉点,形成不稳定三角网。为了解决这一问题,提出了一种基于三角形分解的三角网切割算法,根据三角形与裁剪线的位置关系,对三角形进行分解裁剪,分解时不引入非裁剪多边形边上的交点。实验结果表明分解裁剪算法能避免裁剪结果中出现T交叉点,有效生成稳定三角网。Triangular mesh clipping is widely used in grid reconstruction, grid deformation, terrain fusion and analysis, and many other fields. In the application of geographic information system （GIS）, triangular mesh clipping is the key to the fusion of terrain surface model and building model. However, existing polygon clipping algorithms do not take the space relationship of adjacent triangles into account.If they were directly used in triangular mesh clipping, T-intersections would appear in the cutting results, leading tounstable triangular mesh. In order to solve this problem, a triangular mesh clipping algorithm based on triangular decomposition is proposed. Triangular decomposition is implemented according to the location relationship between the triangle and the cutting line, whichdoes not introduce other intersections that are not on the polygon line. Results of the experiments show that the decomposition algorithm can avoid T-intersections and effectively generate stable triangular mesh.

关 键 词：三角网切割 T交叉点 分解裁剪 多边形裁剪 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]