Study On Technologies Of Flash-streaming Based Real-time Rendering Geographic Information

WebGIS application now has become a bottom-up mass communication system that led by the people who got the collective wisdom and strength from Internet. Depended on massive computing resources, the Internet webOS systems become a reality. The client-technology with highly interactive, rich user experience and unity performance of geographic information data becomes the urgent needs of WebGIS development.Flash-based rich client of WebGIS integrated lots of frontier of GIS technology, including geographical distributed computing, multi-source spatial data rendering, open geo-spatial information dissemination, etc. With support of public map service and traditional GIS platform services, flash-based rich client of WebGIS share the geographical information effectively in the traditional field of Internet information communication, it also provide a kind of method that can be directly observed, analysis, reveal the internal relations between the data. So that will be a solution of upgrade browser for WebGIS.Against the above issues and phenomena, this paper carried out research work, mainly includes the following:1. Analyze and organize the WebGIS application requirements and development status in the flash platform. Design a run-time framework for rendering GIS data adaptively and study the geographic information systems in the light of the specific business environment.2. Of the problems for geographic data transmission in WebGIS, combined with the characteristics of Flash data streaming under the P2P protocol, this paper used a distributed hash table algorithm for node organization in the network, studied a non-centralized search mode of resource, which mean the less rich network data transmission and more effectively data sharing.3. Discuss the issues that related to the data stream format in Flash platform, design GIS data transmission channels under P2P streaming media transfer protocol and to study the actionscript class mapping techniques. Study back-end technology environment to support Flash client, such as BlazeDS. 4. Develop a flash-based streaming media transmission framework, real-time rendering system of urban planning systems that designed as Spring-Hibernate architecture to verify the research on the content of this paper.