add purge

src/Model/Geometry/PointXYZ.py

@@ -204,3 +204,11 @@ class PointXYZ(Point, SQLSubModel):
             Euclidean distance between the two points
         """
         return dist((p1.x, p1.y, p1.z), (p2.x, p2.y, p2.z))
+
+    @staticmethod
+    def areatriangle3d(p1, p2, p3):
+        a = PointXYZ.distance(p1, p2)
+        b = PointXYZ.distance(p2, p3)
+        c = PointXYZ.distance(p3, p1)
+        s = (a + b + c) / 2
+        return (s*(s-a) * (s-b)*(s-c)) ** 0.5