摘要
越来越多的三维应用需要绘制椭球大地,以体现真实的地理环境。要构建一个三维地球,首先需要有能力对全球海量数据进行高效访问与处理;其次为了实现对全球地形与地物的快速绘制,在构造场景时必须对地球表面进行层级分块,以便只载入需要的地理数据并构造它们的场景;另外为了得到恒定帧速,构造新场景的工作应放进后台线程中。给出了一个基于GIS的三维虚拟地球的系统设计,对其中的关键技术作了重点讨论,实现了一个原型系统TerraGlobe。
More and more 3D applications need to render global data on the sphere, to represent the real world. Constructing a 3D Globe needs to consider many problems, Firstly, it is necessary to access and process huge geographic data; secondly, in order to render global terrain and features in no time, one need to subdivide earth surface into tiles and organize them into quad trees so that we need only load necessary data and build geometries for them. In addition, the task of loading data and building geometries should be put in background thread to achieve constant frame rate. An integrated virtual 3D globe system named TerraGlobe is presented, which supports visualization of global multi-resolution terrain elevation data, imagery data and vector data. Some kernel technologies are discussed in detail, according to their implementation in TerraGlobe.
出处
《计算机工程与设计》
CSCD
北大核心
2007年第19期4774-4777,4809,共5页
Computer Engineering and Design
