一种新的三维地景库的建模方法

针对传统的模拟器计算机成像系统之不足，提出了1种新的视景系统的建模方法，即基于矢量数字地图的三维地景生成算法。该算法以矢量地图为约束，各种地表纹理作为输入样图，用矢量地图中的高程信息构建三维地形网格，并根据矢量数字地图中图元之间的不同属性映射相应的纹理，得到了与矢量数字地图相一致的三维地景。与传统的地景库生成算法相比，新算法生成的三维地景更加真实精确；解决了以往地景库一经生成就无法更改的问题；具有一定的预测和重现场景的功能；缩短了地景库的开发周期，降低了开发成本。同时，运用了基于视点的地景数据动态调度策略，可实现真实场景的实时绘制。

A New Modeling Method of Generating Three-dimensional Terrain Database

In order to improve the traditional method of generating terrain database,we present a novel algorithm in this paper.This algorithm makes vector digital map as restriction and various terrain textures as input samples,build three-dimensional terrain mesh from the elevation of vector digital map.The textures are mapped according to the different attributes of vector digital map,then a three-dimensional terrain scene consistent with the vector digital map is generated.Comparing with the traditional method of generating three-dimensional terrain scene,this new algorithm is more lifelike and accurate.The database based on this method can be changed after it is generated.This new algorithm also has some functions of previewing and reviewing the scenes,shortens developing time and reduces the whole cost.At the same time,the reality scene of real-time rendering can be implemented by using dynamic data schedule strategy based on view point.