面向山地灾害动态过程仿真的地形三维建模与可视化

基于山地灾害动态过程仿真需要的考虑,并针对该动态过程仿真时渲染数据量过大所造成的实时性较差的问题,提出了利用改进的三角形二叉树LOD算法实现地形三维建模与可视化的方法。算法对山地地形数据进行了分层和分块的预处理,用三角形二叉树表示地形网格,并结合视点和局部地形的粗糙程度,动态的载入所需的地形块和释放无用的地形块,使得内存中的地形数据维持在一定范围内。实验结果表明;在对地形渲染不失真的前提下,本方法能够有效地提高地形绘制的效率,可应用到大规模山地地形的三维建模与可视化中去,为整个山地灾害的动态过程仿真奠定了良好的基础。

3D Terrain Modelling and Visualization for Dynamical Process Simulation of Mountain Disasters

In correspondence with the requirement of dynamical process simulation of mountain disasters and the drawbacks of rendering the whole process of mountain disasters dynamic simulation in real time,the improved LOD algorithm based on the triangle bintree data structure,is proposed,to realize 3D modelling and visualization of mountainous terrain.It performs pretreatment of blocking and layering for mountainous terrain data,and uses triangle bintree to represent terrain meshes.It also dynamically split or merge data blocks with quadtree structures according to viewpoints as well as the roughness in local terrain,which limit the terrain data in the memory.The experimental result shows that the method presented in this paper is feasible and efficient,has a low memory expenses,it can be used to realize real time rendering of very large-scale terrain,which lays a good foundation for whole dynamical process simulation of mountain disasters.