From 9ab1372c7bbf86dec7016f38676bd12a26243acd Mon Sep 17 00:00:00 2001
From: Jan Petykiewicz <anewusername@gmail.com>
Date: Mon, 13 May 2019 23:55:14 -0700
Subject: [PATCH] Allow shapes to carry an arbitrary identifier (Tuple)

---
 masque/shapes/shape.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/masque/shapes/shape.py b/masque/shapes/shape.py
index 7e26c87..46123a1 100644
--- a/masque/shapes/shape.py
+++ b/masque/shapes/shape.py
@@ -34,6 +34,9 @@ class Shape(metaclass=ABCMeta):
     # Dose
     _dose = 1.0                         # type: float
 
+    # An arbitrary identifier for the shape, usually not set but used by Pattern.flatten()
+    identifier = ()                     # type: Tuple
+
     # --- Abstract methods
     @abstractmethod
     def to_polygons(self, num_vertices: int, max_arclen: float) -> List['Polygon']: