Based On Dem Data Of The Three-dimensional Terrain Modeling And Realization

In 1980s,the developed countries had begun their research and development on digital battlefield. The virtual digital battlefield environment has been being a hotshot worldwide since the 21st century entry. The technique of 3D terrain generation is the key technique in the virtual digital battlefield environment construction,where scene reality,multi-resolution and attribute query ability on terrain model are desired.In this dissertation,I discuss model data obtainment and model generation methods. I also implement a prototype system in the practice. The research comes up with the terrain requirement of virtual digital battlefield environment and it is based on the advance research project of national defense.Model data obtainment is the precondition for model generation. The dissertation discusses digital elevation model (DEM) in several aspects,besides,designs and achieves two kinds of processing methods of DEM data files,file segmentation and section select,which makes it facile to obtain desired data from data source.The dissertation puts emphases on the study and realization of the methods for 3D terrain generation. Firstly,Steps and algorithms for the RTN and TRN methods are studied. Secondly,the TIN methods are brought forward. The dissertation expatiates on the Delaunay triangulation theory of a point set within a 2D arbitrary domain (denoted as DT (D,V) for short),and analyses DT (D,V) algorithms. After applying DT (D,V) theory to 3D terrain modeling,the dissertation resolves the problem of boundary points and filtering points,and simplifies the insertion algorithm in practice. Thirdly,the dissertation compares the advantages and disadvantages of three methods,and come to a qualitative conclusion. The dissertation presents a new method named mixing modeling based on RTN,TRN and TIN methods,the advantages of which are integrated and disadvantages improved.Finally the dissertation discuses a prototype system ( ReliefMS ),which provides DEM file proceeding,terrain modeling and model visualization and manipulation.