城市建筑物三维可视化逼真度优化设计仿真

Optimization Design and Simulation of 3D Visualization of Urban Buildings

对城市建筑物三维可视化逼真度设计,可真实的展现建筑物的整体形态及建筑规模,提高城市规划工程的效率。进行可视化逼真度设计时,经常出现场景内几何体相交并发生碰撞的现象,应给予消除。传统方法通过采集建筑物几何图像数据及三维位置点数据信息,结合二者进行逼真度设计,但不能对几何体碰撞现象进行有效检测和消除,降低了城市建筑可视化的逼真度。提出基于Unity3d的城市建筑物可视化逼真度设计方法。在虚拟仿真系统中构建建筑物三维LOD模型,利用基于边折叠渐进网格模型简化算法,运用给定的原始模型,基于误差判定标准,实现边折叠操作简化后形成最简网格模型,实现不同模型间的平滑过渡;采用改进型混合层次包围盒碰撞检测算法,通过检测算法来检验场景中的几何体是否相交并发生碰撞,可快速排除不会碰撞的对象。最后,将构建的建筑物三维模型导入Unity3d系统中实现建筑物可视化效果,完成城市建筑物三维可视化逼真度设计。仿真结果表明,利用Unity3d技术仿真系统能够将城市建筑物进行虚拟场景真实显现,精确度较高,为城市规划及改造提供了理论指导。

In this paper, we proposed a design method for 3 D visualization fidelity of city building based on the Unity3d. Firstly, the we built the 3D LOD model of building in the virtual simulation system and used the edge collapse progressive grid model to simplify the algorithm. Then, we used the initial model to form the simplest grid model after achieving the simplification of edge collapse operation based on error judgment criterion and achieved the smooth transition among different models. Moreover, whether the geometry intersect and collide in scene were detected through the modified collision detection algorithm of mixture hierarchical bounding-box. The method can rapidly excluded the object without collision. Finally, the building 3D model was guided into the Unity3D system to achieve the building visualization effect and the 3D visualization fidelity design of city building was completed. The simulation results show that the simulation system using the Unity3D technology can display the virtual scene of city building into reality. It has higher precision and provides a theoretical direction for city planning and transformation.