Study And Design Of Public Service Platform For 3D Simuation Digital City

In recent years, with the acceleration of urbanization, urban areas continue to reconstruct and expand; the information within city is also keep changing, but the city information service falls behind. Which bring challenges to the city's scientific management and also have an impact on people's basic needs. With the background of constructing digital cities in the whole country, building and efficient public service platform for the government and the general public to provide friendly, easy to use geographic information services become a digital city research topic needed to be solved. Based on "Jilin Digital City Public Service Platform" system and actual needs, this paper presents the study about the key issues of constructing public service platform and provides a public service platform solution. The main work is as follows:(1) The design of public service platform system:Based on the analysis of users need, this study discusses the architecture design of public service platform system and function module design.(2) The study of spatial data organization:Spatial data of public service platform is composed of the multiple view angles 3D simulation maps, high resolution remote sensing image and two-dimensional maps. Based on the pyramid model, we give a group pyramid model to adapt to map data organization with many types, a large amount of data.(3) The study of multiple viewing angles 3D simulation map:Displaying the 3D simulation map through a single viewing angle has an inevitable geographic data losing problem due to occlusion. This study presents a solution about multiple viewing angles 3D map to view geographic information in the same area from different angles. The solution is divided into three aspects, including customizing coordinate system of 3D simulation map, coordinate transformation between 3D simulation map coordinate system and geographical coordinate system and implementing rotation of 3D simulation map.(4) The study of data preprocessing bus transfer serviceBased on multiple viewing angles 3D simulation map, taking into account the actual needs of people travel, the study presents a bus transfer service between any two locations in the city, including bus network data structure, bus transfer algorithm research and bus transfer data preprocessing method.(5) The Implementation of public service platform:The study represents the details in the main functions realization of public service platform, including map initialization; map roaming; map labeling; map navigation; map search; public transport query and map building functions.