Research On WebGL-based 3D Model Visualization Method For Geological Body

When implementing concealed underground works,many difficulties are often encountered due to lack of information about the geological conditions.Therefore,constructing a 3D model of the geological body based on the borehole data and designing a reasonable excavation plan through the visualization effect of stratigraphic space spreading can effectively reduce the construction difficulty of underground projects and reduce the occurrence of safety accidents.The true 3D modeling of the geological body is one of the core problems of geological information system,and the construction and visualization of the 3D model of the geological body is important for engineering construction and safety production.To solve the problems of missing model attribute expression and inability of spatial analysis in 3D modeling,a new method of constructing a grid geological model using constrained Delaunay tetrahedral dissection and visualizing 3D model based on Web GL is proposed.In this paper,the 3D modeling and visualization analysis of geological bodies are studied,the details are as follows:(1)The Delaunay tetrahedral dissection is performed using a triangular mesh constraint model for geological model sectioning.The Delaunay constraint is realized for triangles within the local boundary polygon,which can keep the three-dimensional shape of the geological body while retaining the favorable properties of Delaunay tetrahedral dissection and achieving the internal body element feature acquisition.After quality inspection,a conforming tetrahedral lattice is obtained.This method can complete the tetrahedral dissection quickly and accurately,preserving the detailed features while completing the 3D modeling of the geologic body and the optimization of the model with high efficiency.(2)The design of geological model interactive functions.A series of interactive functions are designed for 3D model display,including mouse picking up object information,object attribute selection and analysis,dynamic display of scene and multi-scale expression of model,which realized the query and analysis of 3D model of geological body.Finally,these interactive function modules are tested and basically meet the requirements for visualization of 3D geological bodies.(3)3D visualization method of geological body.The non-regular voxels generated by the geological body model dissection are spatial tetrahedra,and attribute query and analysis are performed for individual tetrahedral voxels.Using the visualization features of Web GL,the experimental system of 3D visualization of geological body is designed to realize functions such as query mode,attribute analysis,parameter calculation,scene roaming and detailed level model display.This paper realizes the 3D display of geological body model based on the rich 3D visualization functions of Web GL platform,so that the independent attributes of all non-regular body elements of the model can be preserved and displayed,and lays the foundation for the application of spatial query and analysis of geological body 3D model.The 3D modeling method combined with visual spatial representation proposed in this paper not only realizes rapid and accurate tetrahedral dissection of 3D geological bodies,but also completes the organization and management of model data,strengthens the spatial analysis capability of the model,and broadens the research and application of the model in the field of geology.