数字区调中大型三维地形实时绘制方法的实现

The realization of ROAM algorithm for large-sized 3D terrain rendering in digital regional geological survey

数字化区域地质调查需要更多信息丰富、直观的表现形式,以更大程度辅助区调填图,并作为最终的载体,生成满足相关领域需求的实地三维模型。本文以区域地质调查中所采用的规则网格数字高程模型为基本数据,采用视域相关的细节层次(LOD)网格优化技术,并选用ROAM实时自适应算法,兼顾不同地物的重要程度,选择相应的细节层次,以期通过减少绘制单元总数量,提高系统运行效率。

In order to assist regional geological mapping,the Digital Regional Geological Survey(DRGS)needs more abundant and visualized expression forms,so the 3D terrain model is adopted as the carrier for the demands in many correlative fields.Based on the regular grid DEM(Digital Elevation Model)in DRGS,ROAM(Real-time Optimally Adapting Meshes)algorithm is used to create dynamic model,which can give consideration to the importance of different features and select correspondence level of detail.How to reduce the total number of detail units and improve the system efficiency is the purpose to use the ROAM arithmetic.The realizing of the whole algorithm indicates that a better effect has already been required.