Technological Research On 3D VGE Modeling Of Songhua River Valley (Jilin Province Part) Based On RS And GIS

Water resource is a reproducible resource important for one country, and a recycling resource in industry and agriculture for human activities. River and lake are the important carrier of water resource, and a substantial foundation for utility and development of water resource. And the geographic environment which river and lake locate is an important portion of land ecosystem, it plays an important role in sustainable development of human society. If we can study the utility of water resource, supervise the change of water environment, predict the evolvement of water environment in one virtual geographic environment which simulate real geographic environment, there are more advantages in the whole scientific research of geography. Considering the importance of Songhua river valley location, the representative of its distributing, diversity of its ecosystem, complexity of its utility and development, we take it as a researchable region. In this paper, we use new-generation RS information source—MODIS data to create 3D virtual geographic environment by processing RS image information and fusing multi-source GIS information with technique of GIS, Visualization, Virtual reality and 3DS MAX modeling to show the valley`s spatial information as visual, real-time and exactly as possible. So it make us analyze and simulate the ecosystem of Songhua river valley in Jilin province to provide information service and decision-making support on the work of supervision of water pollution, dynamic evolvement of environment, reasonable landuse, programming of city construction, protection of ecosystem, local development of economy and society that the whole development of Jilin provincial economy will boost and the sustainable development of human subsistence environment will achieve in the end. The main aim of research is to generate a virtual geographic environment of valley synthesizing data of RS and GIS with VR and 3D modeling technique. The whole modeling process will visualize data and model to help users get a new viewpoint to understand synthesizing of various data and model building. After sufficiently analyzing the principle and method of fusing multi-information source data, the application perspective of 3D Visualization technique and current situation and direction of RS, GIS, VR, we find that traditional RS does not meet technological demand as data source, resolution and scanning range can not be used adequately according to each other in large region image, its application only limits to 2D image analysis. We also find the deficiency in ability of 2D data of GIS to visualize 3D spatial information. Though TIN makes 3D visualization of terrain data possible, its limitation lies in 3D modeling. VR can not be widely used for lack of necessary data for its key technology—dynamic environment modeling. Therefore, how can we adequately synthesize three parts` data trait and technique advantages is the emphasis and direction of scientific research in geography. To combine advantages of each three aspects, we take images processing from RS data source and special layers creating from GIS as data support and take model building with VR technique as final interface of data. According to the thought, the research designs modeling of virtual geography environment of The second Songhua river valley for actual application in three main parts: synthesizing of RS information data, synthesizing of GIS data and modeling of virtual geography environment with 3DS MAX. Synthesizing of RS information data mainly contains choosing RS information source and processing RS data. For new-generation RS information source—MODIS data take more advantages (high resolution (250m), large cover area, free to acquire) than traditional RS information source, it absolutely fit the research of region. And then we use ENVI software to integrate, enhance, spatially mate, geometry correct RS data to generate RS orthograph for overlapping on 3D model. Synthesizing of GIS data first digitize various GIS data including basic geography data, so...