implemented segments

path.py

@@ -9,6 +9,8 @@ class Path:
         self._init_normals()
 
     def _init_normals(self) -> None:
+        pt0 = self.points[0]
+        self.normals.append(Vec2(pt0.y, -pt0.x))
         for i in range(1, len(self.points) - 1):
             pt1 = self.points[i-1]
             pt2 = self.points[i]
@@ -22,3 +24,6 @@ class Path:
                 d = -d
 
             self.normals.append(d)
+
+        ptl = self.points[-1]
+        self.normals.append(Vec2(ptl.y, -ptl.x))