摘要

2D GIS systems are currently widely used in agricultural landscape planning for the handling and analysis of spatial data, but they are limited in the capacity to visualize planners' efforts. The 3D visualization technology, however, is able to allow designers, viewers and the public to create a popular, vivid platform of direct communication. Therefore, it is necessary to integrate 2D GIS and 3D visualization technology for agricultural landscape planning. The key to such integration is the way to render the 2D GIS layer in a 3D environment. In order to solve this problem, a rendering framework based on the concept of levels of detail (LOD) mechanism has been established, which overlays the 2D GIS layer on a 3D terrain, and a model of application has been developed based on ArcGIS Engine and Word Wind. In this application, the rendering framework is implemented and both the parsing and rendering of COLLADA format model are extended. Finally, it is indicated through a planning demo that this application is able to perfectly meet the visualization demands from agricultural landscape planning by rendering 2D GIS data and planning outcomes in a 3D environment.