限定TIN与CSG集成仿真模型生成算法研究

为了有效地组织和管理三维GIS空间数据，实现对三维空间实体高效、完整地表达，提出了限定不规则三角网（TIN）与构造实体几何（CSG）集成的仿真建模算法。采用TIN模型描述地形，CSG模型描述建筑物，通过抽取建筑物地面轮廓线作为地形三角剖分时的限定约束条件，将两种模型有机集成在一起。同时，实现了两类模型可视化渲染操作的同步进行。仿真试验结果表明，算法在保证模拟精度的前提下，能有效地简化建模过程，在一定程度上降低了可视化渲染计算的复杂度。

Integrated simulation algorithm based on constrained TIN and CSG

In order to organize and manage 3D GIS spatial data effectively, and represent 3D spatial entity integrally, a new simulation modeling algorithm was put forward, which combined data structures of constrained Triangulated Irregular Network (TIN) and Constructive Solid Geometry (CSG). In this algorithm, TIN model was used to represent terrain and CSG model was used to represent buildings. The two simulation models were integrated by extracting ground contour lines of buildings as constrained conditions when carrying out triangulating terrains. And the visualization for all parts of the integrated model can be processed synchronously. The results of simulation experiments demonstrate that the algorithm simplifies modeling process and to a certain extent, reduces computing complexity for visualization.