A method for LOD generation of 3D city model based on extended 3D R-tree index

Automatic LOD generation is the difficult problem in computer graphics and 3D GIS. This paper presents a new method to generate the LOD Model. It utilizes the hierarchical structure of R-tree to integrate LOD model. In order to decrease the objects to be rendered, the view frustum culling algorithm is also put forward. The method extends the structure of R-tree, which can manage objects in the intermediate nodes. From bottom to top, the objects in the different layers can be generated. Then, LOD parameters of layers also are defined respectively. Experiments prove that this method is of great benefit to the practice of 3D GIS, and especially fits the building LOD representation.