add paths.py

axi/paths.py

@@ -0,0 +1,26 @@
+from spatial import Index
+
+def sort_paths(paths, reversable=True):
+    first = paths[0]
+    paths.remove(first)
+    result = [first]
+    points = []
+    for path in paths:
+        x1, y1 = path[0]
+        x2, y2 = path[-1]
+        points.append((x1, y1, path, False))
+        if reversable:
+            points.append((x2, y2, path, True))
+    index = Index(points)
+    while index.size > 0:
+        x, y, path, reverse = index.search(result[-1][-1])
+        x1, y1 = path[0]
+        x2, y2 = path[-1]
+        index.remove((x1, y1, path, False))
+        if reversable:
+            index.remove((x2, y2, path, True))
+        if reverse:
+            result.append(list(reversed(path)))
+        else:
+            result.append(path)
+    return result