Abstract: Three-dimensional visualization models for extra large scale landscape geomorphology are the important parts of VR system platforms.Due to the complexity of terrain models，the development speed of computer hardware is far from satisfaction for real-time rendering of large scale terrain model.There are some problems such as data processing slowly and scalable poorly in this field now.So this paper puts forward a new method of terrain creating.It is based on lots of little terrain tiles to splice extra large scale terrain by mains of counter clockwise（CCW）.And it solves the problem of index searching by idea of matrix.The experiments show that this method is easy to scalable.

Key words: extra large scale landscape, terrain model, scalable, splice, matrix

摘要： 超大场景的三维地形可视化模型是虚拟现实系统平台的重要组成部分。由于地形模型的复杂性，致使计算机硬件水平一直难以满足超大规模地形模型的实时显示需求。目前的超大场景三维表现上存在数据处理速度慢，可扩展性差等问题。为此，提出了一种新的地形创建方法，该方法以许多小的地形分片为基础，采用逆时针旋转的方式拼接出超大的地形，采用矩阵的思想进行索引值搜索。实验结果表明，该方法创建的地形具有可扩展性。

关键词: 超大场景, 地形模型, 可扩展, 拼接, 矩阵