基于三维GIS的现代化营房快速建模方法

Rapid Modeling Method of Modern Barracks Based on 3D GIS

因现代化营房范围大、区域多,增加了建模的工作量与复杂度,极大程度影响建模速率,为此,本研究以三维GIS(Geographic Information System,地理信息系统)为技术背景,设计出一种现代化营房快速建模方法。利用数字高程模型表面表达式与不同表面性质的建模通用多项式函数,构建双线性数字高程模型表面。基于格网数据与土坑底点以及外沿线的高程数据,获取抛物曲面表面。将营房框架拆解成屋顶、门廊、建筑主体等简易对象,得到简易对象的点、线、面状等几何表达形式。采用投影中介平面法向量,架构各墙面法向量表达式,求取中介平面上墙面顶点投影坐标。在中介平面中架构二维平面坐标系,得到二维坐标系内各投影点的相对坐标,归一化纹理坐标,映射全部顶点至纹理空间,实现模型构建。经过实验结果证明,该方法具有较好的建模效果,总建模时长为64.82 s,大幅度提升了建模速度。

Because the modern barracks have a large range and many areas, it increases the workload and complexity of modeling, and greatly affects the modeling speed. Therefore, this study takes 3D GIS(Geographic Information System) as the technical background,and designs a fast modeling method for modern barracks. The surface expression of DEM and the general polynomial function of different surface properties are used to construct the surface of DEM. Based on grid data, pit bottom points and elevation data along the outer line, the parabolic surface is obtained. The framework of barracks is disassembled into simple objects such as roofs, porches and main buildings, and the geometric expressions of simple objects such as points, lines and surfaces are obtained.The normal vector of projection medium plane is used to construct the normal vector expression of each wall surface, and the projection coordinates of the wall surface vertex on the medium plane are obtained. The relative coordinates of each projection point in the two-dimensional coordinate system are obtained, the texture coordinates are normalized, all vertices are mapped to the texture space, and the model is constructed. The experimental results show that the method has good modeling effect, the total modeling time is 64.82s, which greatly improves the modeling speed.