diff --git a/floorshapes.cpp b/floorshapes.cpp
index 021ba8d0..28fddccf 100644
--- a/floorshapes.cpp
+++ b/floorshapes.cpp
@@ -395,6 +395,12 @@ void geometry_information::generate_floorshapes_for(int id, cell *c, int siid, i
       if(!siid) {
         for(int i=0; i<cor; i++) cornerlist.push_back(hpxy(0,0));
         }
+      else if(geosupport_chessboard()) {
+        for(int i=0; i<cor; i++) {
+          hyperpoint nc = nearcorner(c, i);
+          cornerlist.push_back(mid_at(hpxy(0,0), nc, .94));
+          }
+        }
       else {
         for(int i=0; i<cor; i++) {
           int ri = i;
diff --git a/pattern2.cpp b/pattern2.cpp
index 4c56dca6..aeedb0bb 100644
--- a/pattern2.cpp
+++ b/pattern2.cpp
@@ -1979,9 +1979,18 @@ EX namespace patterns {
     dialog::addBreak(100);
 
     dialog::addBoolItem_action(XLAT("display the inner walls"), innerwalls, '5');
-    dialog::addBoolItem(XLAT("display only hexagons"), (whichShape == '6'), '6');
-    dialog::addBoolItem(XLAT("display only heptagons"), (whichShape == '7'), '7');
-    dialog::addBoolItem(XLAT("display the triheptagonal grid"), (whichShape == '8'), '8');
+    
+    if(geosupport_threecolor() == 2) {    
+      dialog::addBoolItem(XLAT("display only hexagons"), (whichShape == '6'), '6');
+      dialog::addBoolItem(XLAT("display only heptagons"), (whichShape == '7'), '7');
+      dialog::addBoolItem(XLAT("display the triheptagonal grid"), (whichShape == '8'), '8');
+      }
+    
+    if(geosupport_chessboard()) {
+      dialog::addBoolItem(XLAT("display only chessboard white"), (whichShape == '6'), '6');
+      dialog::addBoolItem(XLAT("display only chessboard black"), (whichShape == '7'), '7');
+      }
+
     dialog::addBoolItem(XLAT("display full floors"), (whichShape == '9'), '9');
     dialog::addSelItem(XLAT("floor type"), XLATN(winf[canvas_default_wall].name), 'i');