一种Web端图形引擎中自定义空间多边形面积的计算方法

A calculation method of custom space polygon area in Web graphics engine

伴随WebGL技术的发展,Web端上的图形引擎应用越来越广泛。研究发现,当前大多数图形引擎在线测量功能无法正确测量自定义空间多边形面积。本文按照三点共面的原理,自动拾取空间中同一平面的点,利用线段相交判断方法规避多边形区域重叠,最终将不规则的多边形拆分为多个三角形,利用海伦公式及点和区域的相对关系正确计算自定义多边形的面积。该计算方法扩展了Web端图形引擎的测量功能,对BIM行业在线测量和在线规划有重要意义。

With the development of WebGL technology,graphics engine on Web is more and more widely used.It is found that most of the online measurement functions of graphics engines cannot correctly measure the area of custom spatial polygons.According to the principle of three points coplanar,points on the same plane in space are automatically picked up.The intersection judgment method of line segments is used to avoid overlapping polygon areas.Finally the irregular polygon is divided into multiple triangles,and the area of the custom polygon is calculated correctly by using Heron’s formula and the relative relationship between points and areas.This calculation method extends the measurement function of the Web graphics engine,and is of great significance to the on-line measurement and on-line planning of BIM industry.