三维电子海图地形可视化技术研究

针对三维海底地形数据获取和多分辨率显示展开对三维电子海图的研究.利用加权平均法将从二维电子海图中提取的水深数据插值为规则格网数据,并采用四叉树结构对数据进行组织.为提高散乱地形数据检索效率,给出了一种散乱数据索引方法.基于细节层次思想,设计了一种四叉树节点误差评价系统,以实现地形简化和提高渲染效率.实验结果表明,在实现海底地形连续多分辨率显示的基础上,满足了细节层次思想对图形渲染的要求,并具有较高的显示速度和较好的图形效果.

Terrain visualization technology with three-dimensional ECDIS

Acquisition and multi-resolution display of 3D terrain data were investigated in order to improve electronic chart display and information systems (ECDIS). The depth data acquired from 2D electronic navigation charts was interpolated into regular grid data using the weighted average method and then organized in a quadtree structure. A scattered data index method was presented to improve retrieval efficiency. Based on the required level of detail (LoD), a quadtree node error evaluation method was included to provide terrain simplification and to increase graphical rendering efficiency. Simulation results show that the multi-resolution terrain display satisfies the LoD requirement of graphics rendering, providing a high display rate and satisfactory images.