Volume Rendering Method And Prototype System Based On SDOG-ESSG

Technologies of space exploration, computer science, information science enable the methods of data accessing diversified, and thus make humans being rich in information. As a 3D spatial fundamental reference frame, SDOG-ESSG model provides the foundation for modeling and visualization. Visualization of SDOG-ESSG still primarily depends on traditional methods with geometric primitive. However, traditional methods are difficult to express and display the whole 3D geospatial data, especially global 3D data field. Volume rendering method makes up for insufficiency of geometric primitive drawing method on intuition and integrity. Due to the special nature of SDOG-ESSG, however, the existing methods are not applicable. According to this, the paper focuses on the study of global 3D data field volume rendering, even focused on volume rendering of SDOG-ESSG. Improving algorithm and data store strategy based on traditional ray-casting method to realize real-time volume rendering of large scale 3D field.The main contents of this dissertation are expressed as follows:Firstly, in view of the present situation this paper presents a SDOG-ESSG volume rendering method on the basis of traditional ray-casting method. This approach adopts a grid-based data sampling method and a fast approach to compute the intersections of grid on basis of closer space relationship.Secondly, this paper presents a linear memory construction approach to store data based on the model structure of SDOG-ESSG. This approach allows random access to data and improves data access efficiencies.Thirdly, under analyzing the CUDA programming model, the parallel programs were given. Prototype System had been realized including reel-time volume rendering, dynamic sequential volume rendering and profile visualization.