From e70915de9d0e1184e916b4ba30d3a55ea0b22422 Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Sat, 21 Mar 2020 10:14:54 +0100
Subject: [PATCH] fixed distance computation in 3D fieldquotient

---
 cell.cpp         | 6 ++++--
 fieldpattern.cpp | 9 +++++++++
 pattern2.cpp     | 2 +-
 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/cell.cpp b/cell.cpp
index 64b249a3..388da364 100644
--- a/cell.cpp
+++ b/cell.cpp
@@ -1064,8 +1064,10 @@ EX int celldistance(cell *c1, cell *c2) {
   if(hybri) return hybrid::celldistance(c1, c2);
   
   #if CAP_FIELD
-  if(geometry == gFieldQuotient && !GOLDBERG)
-    return currfp.getdist(fieldpattern::fieldval(c1), fieldpattern::fieldval(c2));
+  if(geometry == gFieldQuotient) {
+    int d = fieldpattern::field_celldistance(c1, c2);
+    if(d != DISTANCE_UNKNOWN) return d;
+    }
   #endif
   
   if(bounded) return bounded_celldistance(c1, c2);
diff --git a/fieldpattern.cpp b/fieldpattern.cpp
index 9d13446d..8cc90e0f 100644
--- a/fieldpattern.cpp
+++ b/fieldpattern.cpp
@@ -1313,6 +1313,15 @@ int hk =
 
 EX purehookset on_geometry_change;
 
+EX int field_celldistance(cell *c1, cell *c2) {
+  if(geometry != gFieldQuotient) return DISTANCE_UNKNOWN;
+  if(GOLDBERG) return DISTANCE_UNKNOWN;
+  auto v1 =fieldpattern::fieldval(c1);
+  auto v2 =fieldpattern::fieldval(c2);
+  int d = currfp.getdist(v1, v2);
+  return d;
+  }
+
 EX }
 
 #define currfp fieldpattern::getcurrfp()
diff --git a/pattern2.cpp b/pattern2.cpp
index fdcc6855..37919c38 100644
--- a/pattern2.cpp
+++ b/pattern2.cpp
@@ -366,7 +366,7 @@ EX int zebra3(cell *c) {
 EX namespace fieldpattern {
 
 EX pair<int, bool> fieldval(cell *c) {
-  if(WDIM == 3) return make_pair(int(c->master->fieldval) * currfp.local_group, false);
+  if(WDIM == 3) return make_pair(currfp.inverses[int(c->master->fieldval) * currfp.local_group], false);
   else if(ctof(c)) return make_pair(int(c->master->fieldval), false);
   else return make_pair(btspin(c->master->fieldval, c->c.spin(0)), true);
   }