如何判断一个多边形是否在另一个多边形内部？

我有一个简单的例子（SVG源）看起来像你可以在下面看到的。这path带有 ID“rect2816”中描述的d属性：

m 140.53571,188.625 0,148.1875 273.9375,0 0,-148.1875 -273.9375,0 z 
m 132.25,42.03125 c 3.64586,0.0236 7.47296,0.12361 11.5,0.28125 36.65941,1.43507 57.84375,15.88072 57.84375,32.84375 0,7.41614 -1.94981,21.58652 -13.28125,24.09375 -14.58711,3.2276 -40.46224,-5.35276 -53.125,6.625 -26.65285,25.21104 -48.00843,-19.04537 -57.875,-32.84375 -12.16196,-17.00847 0.24962,-31.35357 54.9375,-31 z

在这里，第一行描述父多边形，第二行描述孔（如您所见）。但是我怎样才能找到这个漏洞程序呢？我正在使用Python。也许有一些库可以轻松解决？

将路径转换为 ​​(x,y) 对并将此函数应用于第二个多边形的每个点。

# determine if a point is inside a given polygon or not
# Polygon is a list of (x,y) pairs.

def point_inside_polygon(x,y,poly):

n = len(poly)
inside =False

p1x,p1y = poly[0]
for i in range(n+1):
    p2x,p2y = poly[i % n]
    if y > min(p1y,p2y):
        if y <= max(p1y,p2y):
            if x <= max(p1x,p2x):
                if p1y != p2y:
                    xinters = (y-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
                if p1x == p2x or x <= xinters:
                    inside = not inside
    p1x,p1y = p2x,p2y

return inside

Source: http://www.ariel.com.au/a/python-point-int-poly.html