A progressive transmission of spatial data method for 2D/3D integrated GIS

2D/3D integration is an effective solution to the shortage of 3D spatial data and the weakness of 3D spatial analysis. However, with the expansion of spatial data, the congested network flow has become the bottleneck to 2D/3D integrated GIS web services. This paper introduces a progressive transmission of spatial data method for 2D/3D integrated GIS in the web environment. This method includes three steps. First, multi-resolution of representation of 2D and 3D spatial data are generated separately on the server. Second, on the server, a corresponding spatial index would be developed for retrieving the 2D and 3D spatial data effectively in a large scale geographical scene. And last, the spatial data requested by the client would be transmitted from a lower-resolution data version to a higher-resolution data version and from 2D vector data to 3D model data. In our study, an experiment was conducted to evaluate the performance of the proposed approach. Comparing to the traditional transmission methods, the experimental results reveal that the method shortens the server response time as well as the whole transmission time significantly, and enhances the user experience.