Research On 3D Digital Terrain Visualization Method Based On DEM

With the development of 3D model construction technology and visualization technology,the demand for 3D model reconstruction visualization in various fields is also increasing,such as 3D digital terrain visualization application of the construction and site selection based on the Qinghai-Tibet Plateau photovoltaic base.The visualization of 3D digital terrain involves the representation of geospatial information,and the topographic structure needs to be extracted and recombined from a variety of2 D data.Although the geographic information system can effectively solve the needs of geographic information based on satellite images,it cannot effectively meet the needs of 3D terrain model reuse planning,a quick overview of topographical elevation features and mountain undulations,and other requirements,in application scenarios such as base site selection and construction.To this end,this paper through the structured preprocessing of terrain elevation data analyzes the organizational structure of the terrain mesh,draws a 3D terrain elevation information feature map,uses the terrain texture image and the mapping relationship between the gray value information of the image pixel point and the elevation value to build a realistic 3D terrain simulation model,designed and implemented a 3D terrain visualization tool.The main contributions of this paper are as follows:(1)By analyzing the differences in the organization and structure of the terrain mesh surface,using the terrain elevation coordinate data,the irregular terrain triangular mesh surface is drawn in 3D space to achieve quick browsing of the 3D terrain structure.Experimental results show that this method not only supports the processing of actual sample elevation data but also meets the requirements of terrain mesh mapping through self-simulated terrain elevation data.(2)On the basis of the research on the 3D topographic map rendering method,uses the terrain texture image,studies the mapping relationship between the gray value of the image pixel and the elevation data,Combines with monocular image 3D reconstruction method based on Shape From Shading to construct a 3D terrain simulation model.(3)The design implements a 3D terrain visualization tool,providing the above two 3D terrain visualization functions,users can quickly browse the elevation information of the terrain and other 3D features,but also view the model representation of the terrain in 3D space through the realistic simulation angle,and support the storage and re-modification of the common format 3D model file.