A NOVEL QUADRATIC ERROR METRIC MESH SIMPLIFICATION ALGORITHM FOR 3D BUILDING MODELS BASED ON ‘LOCAL-VERTEX’ TEXTURE FEATURES

Abstract. 3D building model is an important part of 3D GIS. However, with the rapid development of data acquisition technology, the data volume of the 3D building model has increased dramatically. Levels of detail (LOD) technology determines the resource allocation for object rendering based on the position (Screen Size) and importance of the nodes of the model in the display environment, reducing the model’s volume and thus obtaining efficient rendering computations. To ensure the smooth rendering and efficient loading of 3D building models, it is essential to simplify the 3D building models to generate LOD. By taking the texture discontinuity and topological complexity into account, this paper proposes a quadratic error metric mesh simplification algorithm based on "local-vertex" texture features for 3D building models simplification. Using the texture features of the model texture map and the vertex curvature at local vertices, we increase the edge collapse cost of the model in the rich texture areas. After each simplification operation, we use centre of gravity coordinate method to optimize the texture coordinates to preserve the model’s detailed features and topological relationships. A series of experimental comparisons with other state-of-the-art methods verify the effectiveness of the proposed method for simplifying 3D building models. The method in this paper helps to maintain the detailed features and topological relationships of 3D building models while reducing the volume of model and better generating LOD for application in 3D GIS.