From 97ca275b70c16de8791a930886d5aa5945af92c2 Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Sat, 18 Apr 2026 19:02:03 +0200
Subject: [PATCH] backed-map:: access as a method

---
 arbitrile.cpp   | 2 ++
 archimedean.cpp | 2 ++
 cell.cpp        | 2 ++
 3 files changed, 6 insertions(+)

diff --git a/arbitrile.cpp b/arbitrile.cpp
index bc5974b0..060a34b6 100644
--- a/arbitrile.cpp
+++ b/arbitrile.cpp
@@ -1529,6 +1529,8 @@ struct hrmap_arbi : hrmap {
   heptagon *origin;
   heptagon *getOrigin() override { return origin; }
 
+  backed_map* get_backmap() override { return &bm; }
+
   hrmap_arbi() {
     dynamicval<hrmap*> curmap(currentmap, this);
     origin = init_heptagon(current.shapes[0].size());
diff --git a/archimedean.cpp b/archimedean.cpp
index 5e4e1088..d5c8b9b7 100644
--- a/archimedean.cpp
+++ b/archimedean.cpp
@@ -577,6 +577,8 @@ struct hrmap_archimedean : hrmap {
   heptagon *origin;
   heptagon *getOrigin() override { return origin; }
 
+  backed_map* get_backmap() override { return &bm; }
+
   hrmap_archimedean() {
     dynamicval<hrmap*> curmap(currentmap, this);
     int id = DUAL ? current.N * 2 : 0;;
diff --git a/cell.cpp b/cell.cpp
index 6158e94a..ec72d0cc 100644
--- a/cell.cpp
+++ b/cell.cpp
@@ -97,6 +97,8 @@ public:
   /** this takes a large closed manifold M that is a quotient of this, and returns a unique identifier of the cell corresponding to M
    *  returns PATTERN_INVALID if not implemented or impossible */
   virtual int pattern_value(cell *c) { return PATTERN_INVALID; }
+
+  virtual struct backed_map* get_backmap() { return nullptr; }
   };
 
 /** hrmaps which are based on regular non-Euclidean 2D tilings, possibly quotient