Parsing And Applying Of HGML On Geo-browser Platform Based On G/S Model

This thesis takes HGML as the main researching object, develops U-Star geo-browser platform based on G/S model and exhibits the features and characteristics on dealing and displaying spatial geographic information data of the platform with the combination of digital tourism project. This thesis deeply analyzes system architecture of current popular geo-browsers and uses Java, JOGL, Ardor3D COLLADA API as the main technology support and HGML as the standard data format of geo-browser application program.Many cities in China start planning Digital City . All the cities want to utilize 3D geographical browser or normal geographical applications to improve the construction of national information and economical competitive ability, to provide well-checked fundamental information resource to all economical subjects, to push the development of the areas around. All the cities aim to be the first one which moves into the knowledge economical period. As we all known, geographical information system is composed of geo-browser and distributed data servers, providing us plenty of spatial geographic information data. Geo-browser is not only a geographical data viewing utility connecting to Internet, but also a independent computer application program. Geo-browser platform based on G/S model is a browser providing public science data exhibition.This thesis mainly discusses the theory and exhibits the applications according to the following points:1. Developing a geo-browser platform based on G/S model which can deal with hundreds of thousands of spatial information data. The geo-browser takes NASA World Wind Java as the main researching object and analyzes the architecture of popular geo-browsers.2. Put forward a parsing method of HGML on geo-browser based on G/S model. First, finding out the content structure of HGML file, then loading and parsing HGML in the geo-browser platform simulating the method that Java uses to parse XML.3. Put forward a method that supports loading COLLADA 3D model on geo-browser platform. And designing a optimized rendering method - LAOIV(Limit Altitude and Only in View) to avoid screen lagging when rendering plenty of layers.