随着视景仿真技术的发展，其应用也涉及各个领域，地形仿真是视景仿真的关键技术之一，其研究具有重要意义。
首先介绍了所用仿真引擎Vega Prime，并说明LADBM模块在管理大形数据库的优势，然后对比大地形制作的诸多方法和关键技术，从实用性和可行性出发，总结出各个方法的优缺点。研究了地形生成管理过程和纹理映射技术，地形各坐标系的关系和转换方法，便于不同地形坐标系之间的转入转出。介绍了以卫星照片为纹理贴图的地形纹理制作方法，应用了基于地理信息光棚图像的地形仿真方法，并利用Creator软件结合访该方法制作出了AOI，通过模型的转换后加载进Vega Prime软件进行仿真，验证了可行性。对比Creator的地形制作，又详细介绍了CTS大地形制作软件的工作流程的原理，对地形制作的关键技术如地形数据动态调度管理方法等做了阐述，并利用CTS软件生成了一个全球地形。
With the development of scene simulation, it is widely used in many fields, terrain scene simulation is on of the most critical technology in scene simulation, its study has important value.
First, we introduces Vega Prime used in simulation,
describing the advantages of LADBM module managing databases of large terrain, then compare many methods and critical technology in making global terrain, for the aims of application and feasibility conclude advantages and disadvantages from every method, researching manage procedure and approcach of texture applying, relation to every coordinate system of earth and how to convert to other, convenient for different coordinate systems switch in-out, introduce method about making terrain mapping texture with imagery, puts forward a way of wide area terrain simulation based on raster image, with this way and Creator set up a large terrain, after convert the terrain data flt to VSB, adding into Vega Prime to simulate, it is proved fesibility. Comparing with other method of making terrain such as Creator, it is described in detail CTS theory and work flow how to build large terrain, also talk about key technology such as data dynamic scheduling manage method, using CTS create a large area terrain, proving its advantages for creating large terrain.
(1)高程数据
DED (2)纹理数据 ２５６×２５６tile 1*1 0 1/2*1/2 1 1/4*1/4 2 (3)culture
树林，草地，山川，道路，建筑，河流，海。建立特征码和表面材质码
输入到CTS生成数据库
LOD技术，主要通过设置模型的Switch In 和Switch Out值来实现不同视点距离显示不同复杂度模型。 解决突变效应，采用两种方法，增大Switch距离和Morphing两种。
数据管理和组织 金字塔模型
１m, 3m, 13m
USGS网站上可以获得全球各地的免费高程信息。 tif/tiff 坐标系
地形GeoTiff－>flt网格 3D模型 5 layer
VegaPrime优化 to_VSB.exe
Creator Terrain Studio
纹理创建－>发形创建－>发布MFT数据库
VP的调度策略 LADBM
VpLADBM(LADBMgeometryGridDataset,LADBMPagingSt
ragegyPoint,LADBMVTCenterComputer)
vpVT(VTCenterIsector,VTTechniqueBumpMapDoT3,VTTEchniqueDefault,VTVirtual TextureMgr)
Texture
Dataset,VTVirtual
914072-计算机科学进展-视景仿真技术
