基于多分辨率半边的分块LOD模型无缝表达  

Seamless Expression of Chunked LOD Based on Multiresolution Half-Edges Structure

作　　者：侯绍洋[1] 赵学胜[1] 官亚勤 

机构地区：[1]中国矿业大学(北京)地球科学与测绘工程学院,北京100083

出　　处：《地理与地理信息科学》2015年第4期18-21,F0003,共5页Geography and Geo-Information Science

基　　金：国家自然科学基金面上项目"顾及多类型数据无缝融合的全球离散格网自适应建模"(41171306);高等学校博士学科点专项科研基金"基于LiDAR点云的地表拓扑建模与形变分析研究"(20130023110001)

摘　　要：为了从格网剖分结构上解决分块LOD(Level Of Details)模型中复杂的块内、块间裂缝问题,避免目前裂缝消除方法的缺陷,该文提出一种基于多分辨率半边结构的分块LOD模型无缝表达方法。首先,引入多分辨率组合映射理论,给出基于多分辨率半边的菱形块多尺度表达的基本方法,包括菱形块剖分方法和编码方法;在此基础上,提出块内、块间格网无缝表达机制,设计并实现了基于菱形块的全球地形动态LOD管理机制;最后,应用C语言和DirectX工具,开发了相应的可视化实验系统。实验表明:该方法从格网剖分结构上解决了全球地形分块LOD模型中的块内、块间裂缝问题;与传统方法相比,其不需要限制相邻格网的剖分层差,简化效率更高,且无地形失真。In order to solve the complicated crack problems of chunked LOD model from the underlying data structure and avoid the defects of crack elimination in the current methods, a seamless expression of chunked LOD is discussed based on multireso- lution half-edges structure in this paper. The main contents are as follows. Firstly, the theory of multiresolution combinatorial maps is introduced and the basic principle and some methods of diamond based on the multiresolution half-edges are proposed, including the subdivision method and encode method. Then, a seamless expression method is proposed within one diamond and between neighboring diamonds, and the management mechanism of dynamic LOD of the global terrain is designed and achieved. Finally, by using C＋＋ language and DirectX tools, an experimental system is developed and the results show that the method in this paper solves the crack problem from the underlying data structure and realizes the seamless expression of chunked LOD model of the global terrain. Compared with the traditional method, the method in this paper does not need to repeatedly check the level difference between the adjacent nodes and it is more effective with no data redundancy.

关 键 词：多分辨率半边 球面菱形格网 裂缝消除 分块LOD 

分 类 号：P208[天文地球—地图制图学与地理信息工程]