| The three-dimensional terrain model is a hotspot of current digital information research.It is of great significance to the simplified terrain model,the hierarchical TIN model and the accurate calculation of engineering volume.The relevant research methods and technical routes are summarized by consulting and analyzing relevant literature at home and abroad.In this paper,the three-dimensional terrain model is simplified,and the triangulation optimization and model volume accurate calculation are the main research contents.Firstly,the big data terrain model is theoretically analyzed,and the geological model is constructed by using the big data 3D geological modeling technology.Simplify the model for 3D terrain,optimize the triangulation structure,and accurately calculate the model volume.The main research contents of this thesis are as follows:(1)Big data terrain simplification: The terrain model is based on the TIN model to construct the Delaunay triangulation model.Based on the detailed study of Delaunay triangulation and LOD technology,this paper uses the detail hierarchy algorithm and Bowyer-Watson triangulation to map the terrain.The establishment of the environment is analyzed.The terrain is studied by the rule grid and the irregular triangulation algorithm in the detail level algorithm.The Bowyer-Watson triangulation technique is used to insert the triangle to which the point belongs,and the redistribution is collected on this basis.The triangle network point set,then analyzes and processes the large data volume terrain environment,and finally makes the time efficiency of the network construction process improve,and realizes the big data terrain simplification;(2)Establishment of hierarchical TIN model: The three-dimensional spatial modeling method can be summarized as based on the current research status of geological layer stratification.The hierarchical TIN model technology algorithm is used to divide the geological space into multiple vertical planes and tangent to the terrain.Profile model.The relationship between the topography and the internal structure in the profile is constructed,and the simulation of the 3D geological layer is realized.(3)Accurate calculation of model volume: The three-dimensional space volume calculation method can be summarized into three methods: square grid method,DTM method and contour method.Based on the full study of these three methods,this paper uses the irregular triangulation DTM method to calculate the volume,and uses the data generation triangulation to calculate the volume of each geological distance field under the proposed design elevation,and realizes the accurate calculation of the model volume..The thesis combines the theory of big data three-dimensional terrain model,and uses the spatial data of Xinjiang to develop the above theory.Finally,the big data model modeling experiment software is designed and developed.The software is able to use the spatial coordinate data to complete the simplification of the big data 3D model,the visualization of the layered model,and the volume calculation of the terrain model. |
