,the aera of any complex concave curved polygon equals that of cropped convex polygons and the by cropped parts.This method is entitled combined triangle algorithm.

• 所以 ,任意凹曲复杂平面图形的面积等于修剪凸多边形的面积与被修剪部分面积的代数和 ,这种方法称为组合三角形算法。