diff --git a/cell.cpp b/cell.cpp
index 502c899b..929d86be 100644
--- a/cell.cpp
+++ b/cell.cpp
@@ -221,7 +221,12 @@ namespace torusconfig {
   // values as the default -- otherwise the three-color
   // pattern breaks. Also, they should have no common
   // prime divisor.
-  int qty = 127*3, dx = 1, dy = -11*2;
+  int def_qty = 127*3, dx = 1, def_dy = -11*2;
+  int qty = def_qty, dy = def_dy;
+  
+  // new values to change
+  int newqty, newdy;
+  int torus_cx, torus_cy;
   }
 
 int decodeId(heptagon* h);
diff --git a/compileunits.h b/compileunits.h
index fcb625b5..993a01f7 100644
--- a/compileunits.h
+++ b/compileunits.h
@@ -59,6 +59,7 @@ bool inv::on;
 #include "config.cpp"
 #include "scores.cpp"
 #include "menus.cpp"
+#include "geom-exp.cpp"
 #include "quit.cpp"
 #include "shmup.cpp"
 #if CAP_ROGUEVIZ
diff --git a/geom-exp.cpp b/geom-exp.cpp
new file mode 100644
index 00000000..c81175f6
--- /dev/null
+++ b/geom-exp.cpp
@@ -0,0 +1,297 @@
+// -- geometry menu --
+
+int eupage = 0;
+int euperpage = 21;
+
+const char *curvenames[8] = {
+  "0", "1", "2", "extremely hyperbolic", "strongly hyperbolic", "strongly hyperbolic", "moderately hyperbolic", "weakly hyperbolic"
+  };
+
+string euchelp =
+  "If you want to know how much the gameplay is affected by the "
+  "hyperbolic geometry in HyperRogue, this mode is for you!\n\n"
+  
+  "You can try many different geometries here. We start by gluing "
+  "n-gons in such a way that k of them meet in every vertex. "
+  "Depending on n and k, this either folds into a sphere, unfolds into a plane, "
+  "or requires a hyperbolic space. The result may be then 'truncated' by "
+  "replacing each vertex by a 2k-gon. Furthermore, you can play "
+  "with quotient geometries. For example, the elliptic geometry is "
+  "obtained from the sphere by making the antipodes be the same point, "
+  "so you return to the same spot (but as a mirror image) after going there. "
+  "Have fun experimenting! "
+  "Achievements and leaderboards do not work in geometry experiments, "
+  "except some specific ones.\n\n"
+  "In standard geometry (truncated or not), you can play the full game, but in other geometries "
+  "you select a particular land. Lands are unlocked by visiting them in this "
+  "session, or permanently by collecting 25 treasure. Try Crossroads in Euclidean "
+  "or chaos mode in non-standard non-quotient hyperbolic to visit many lands. "
+  "Highlights:\n"
+  "* Crystal World and Warped Coast can be understood as extra geometries.\n"
+  "* Halloween is specially designed for spherical geometry.\n"
+  "* To see the difference, try Hunting Grounds in Euclidean -- it is impossible.\n";
+
+int ewhichscreen = 2;
+
+void showQuotientConfig() {}
+
+void showTorusConfig() {
+  cmode = sm::SIDE | sm::TORUSCONFIG;
+  gamescreen(2);
+  
+  dialog::init(XLAT("advanced concfiguration"));
+  
+  dialog::addSelItem(XLAT("number of cells (n)"), its(torusconfig::newqty), 'n');
+  dialog::addSelItem(XLAT("cell bottom-right from 0 (d)"), its(torusconfig::newdy), 'd');
+  
+  if(torusconfig::newqty % 3)
+    dialog::addInfo("best if n is divisible by 3", 0x808080);
+
+  if((torusconfig::newdy + 999999) % 3 != 2)
+    dialog::addInfo("best if d+1 is divisible by 3", 0x808080);
+  
+  dialog::addSelItem(XLAT("scale factor"), fts(vid.scale), 'z');
+
+#if CAP_RUG
+  dialog::addBoolItem(XLAT("hypersian rug mode"), (rug::rugged), 'u');
+#endif
+
+  dialog::addItem("activate", 'a');
+  dialog::addItem("default", 'c');
+
+  keyhandler = [] (int sym, int uni) {
+    if(uni == 'n')
+      dialog::editNumber(torusconfig::newqty, 0, 1000, 3, torusconfig::def_qty, XLAT("number of cells (n)"), "");
+    else if(uni == 'd')
+      dialog::editNumber(torusconfig::newdy, -1000, 1000, 3, -torusconfig::def_dy, XLAT("cell bottom-right from 0 (d)"), "");
+    else if((uni == 'a' || uni == '\n') && torusconfig::newqty >= 3 && abs(torusconfig::newdy) < torusconfig::newqty ) {
+      targetgeometry = gEuclid; restartGame('g');
+      torusconfig::qty = torusconfig::newqty;
+      torusconfig::dy = torusconfig::newdy;
+      targetgeometry = gTorus; restartGame('g');
+      }
+    else if(uni == 'c') {
+      targetgeometry = gEuclid; restartGame('g');
+      torusconfig::qty = torusconfig::def_qty;
+      torusconfig::dy = torusconfig::def_dy;
+      targetgeometry = gTorus; restartGame('g');
+      }
+    else if(uni == 'z') editScale();
+    else if(uni == 'u') rug::select();
+    else if(doexiton(sym, uni))
+      popScreen();
+    };
+  
+  dialog::display();
+  }
+
+void showEuclideanMenu() {
+  cmode = sm::SIDE;
+  gamescreen(0);  
+  if(cheater) for(int i=0; i<landtypes; i++) landvisited[i] = true;
+  for(int i=0; i<landtypes; i++)
+    if(hiitemsMax(treasureType(eLand(i))) >= 25) landvisited[i] = true;
+  landvisited[laCrossroads] = true;
+  landvisited[laIce] = true;
+  landvisited[laHunting] = true;
+  landvisited[laMirrorOld] = true;
+  landvisited[laPrincessQuest] = cheater || princess::everSaved;
+  landvisited[laWildWest] = true;
+  landvisited[laHalloween] = true;
+  landvisited[laWarpCoast] = true;
+  landvisited[laGraveyard] = true;
+  landvisited[laDual] = true;
+  landvisited[laCA] = true;
+  // for(int i=2; i<lt; i++) landvisited[i] = true;
+  
+  if(geometry == gNormal || ewhichscreen == 2) {
+    dialog::init(XLAT("experiment with geometry"));
+    int ts = ginf[geometry].sides;
+    int tv = ginf[geometry].vertex;
+    int tq = ginf[geometry].quotientstyle;
+    int nom = (nontruncated ? tv : tv+ts) * ((tq & qELLIP) ? 2 : 4);
+    int denom = (2*ts + 2*tv - ts * tv);
+    
+    dialog::addSelItem(XLAT("land"), XLAT1(linf[specialland].name), '5');
+    dialog::addBreak(50);
+
+    for(int i=0; i<gGUARD; i++)
+      dialog::addBoolItem(XLAT(ginf[i].name), geometry == i, 'a'+i);
+    
+    dialog::addBreak(50);
+  
+    if(ts == 6 && tv == 3)
+      dialog::addSelItem(XLAT("truncated"), XLAT("does not matter"), 't');
+    else
+      dialog::addBoolItem(XLAT("truncated"), !nontruncated, 't');
+  
+    dialog::addBreak(50);
+  
+    int worldsize = denom ? nom/denom : 0;
+    if(tq & qTORUS) worldsize = torusconfig::qty;
+    if(tq & qZEBRA) worldsize = nontruncated ? 12 : 40;
+    if(tq & qFIELD) {
+      worldsize = size(currfp.matrices) / ts;
+      if(!nontruncated) worldsize = ((ts+tv)*worldsize) / tv;
+      }
+  
+    dialog::addSelItem(XLAT("sides per face"), its(ts), 0);
+    dialog::addSelItem(XLAT("faces per vertex"), its(tv), 0);
+  
+    string qstring = "none";
+    if(tq & qZEBRA) qstring = "zebra";
+  
+    else if(tq & qFIELD) qstring = "field";
+  
+    else if(tq & qELLIP) qstring = "torus";
+  
+    else if(tq & qTORUS) qstring = "torus";
+  
+    dialog::addSelItem(XLAT("quotient space"), XLAT(qstring), 0);
+  
+    dialog::addSelItem(XLAT("size of the world"), 
+      worldsize < 0 ? "exp(∞)*" + (nom%denom ? its(nom)+"/"+its(-denom) : its(-worldsize)): 
+      worldsize == 0 ? "∞" :
+      its(worldsize),
+      '3');
+    
+    switch(ginf[geometry].cclass) {
+      case 0:
+        dialog::addSelItem(XLAT("Curvature"), XLAT("hyperbolic"), 0);
+        break;
+      
+      case 1: 
+        dialog::addSelItem(XLAT("Curvature"), XLAT("flat"), 0);
+        break;
+      
+      case 2:
+        dialog::addSelItem(XLAT("Curvature"), XLAT("spherical"), 0);
+        break;
+      }
+    
+    if(sphere) 
+      dialog::addBoolItem(XLAT("stereographic/orthogonal"), vid.alpha>10, '1');
+    else
+      dialog::addBoolItem(XLAT("Poincaré/Klein"), vid.alpha>.5, '1');
+    if(torus || quotient == 2)
+      dialog::addItem(XLAT("advanced parameters"), '4');  
+    dialog::addItem(XLAT("help"), SDLK_F1);  
+    dialog::addItem(XLAT("back"), '0');  
+    dialog::display();
+  
+    keyhandler = [] (int sym, int uni) {
+      dialog::handleNavigation(sym, uni);
+      if(uni >= 'a' && uni < 'a'+gGUARD) {
+        targetgeometry = eGeometry(uni - 'a');
+        restartGame(geometry == targetgeometry ? 0 : 'g');
+        pushScreen(showEuclideanMenu);
+        }
+      else if(uni == 't') {
+        if(!euclid) {
+          restartGame('7');
+          pushScreen(showEuclideanMenu);
+          }
+        }
+      else if(uni == '2' || sym == SDLK_F1) gotoHelp(euchelp);
+      else if(uni == '3') { viewdists = !viewdists; if(viewdists) popScreenAll(); }
+      else if(uni == '1' && !euclid) {
+        if(sphere) {
+          if(vid.alpha < 10) { vid.alpha = 999; vid.scale = 998; }
+          else {vid.alpha = 1; vid.scale = .4; }
+          }
+        else {
+          if(vid.alpha > .5) { vid.alpha = 0; vid.scale = 1; }
+          else {vid.alpha = 1; vid.scale = 1; }
+          }
+        }
+      else if(uni == '5')
+        ewhichscreen ^= 3;
+      else if(uni == '4') {
+        if(torus) 
+          torusconfig::newdy = torusconfig::dy,
+          torusconfig::newqty = torusconfig::qty,
+          pushScreen(showTorusConfig);
+        if(quotient==2) pushScreen(showQuotientConfig);
+        }
+      else if(doexiton(sym, uni))
+        popScreen();
+      };
+    }
+  else {
+    dialog::init(XLAT("experiment with geometry"));
+    string truncatenames[2] = {" (t)", " (n)"};
+  
+    dialog::addSelItem(XLAT("geometry"), XLAT(ginf[geometry].name) + XLAT(truncatenames[nontruncated]), '5');
+    dialog::addBreak(50);
+    
+    generateLandList(isLandValid);
+    
+    for(int i=0; i<euperpage; i++) {
+      if(euperpage * eupage + i >= size(landlist)) { dialog::addBreak(100); break; }
+      eLand l = landlist[euperpage * eupage + i];
+      char ch;
+      if(i < 26) ch = 'a' + i;
+      else ch = 'A' + (i-26);
+      string validclasses[4] = {"", " (½)", "", " (!)"};
+      string s = XLAT1(linf[l].name);
+
+      if(landvisited[l]) {
+        dialog::addBoolItem(s, l == specialland, ch);
+        }
+      else {
+        dialog::addSelItem(s, XLAT("(locked)"), ch);
+        }
+      
+      dialog::lastItem().color = linf[l].color;
+      dialog::lastItem().value += validclasses[isLandValid(l)];
+      }
+    dialog::addBreak(50);
+    if(chaosUnlocked && !quotient && !euclid && !sphere)
+      dialog::addItem(XLAT("Chaos mode"), '1');
+    dialog::addItem(XLAT("next page"), '-');
+    
+    dialog::addItem(XLAT("help"), SDLK_F1);  
+    dialog::addItem(XLAT("back"), '0');
+    dialog::display();
+  
+    keyhandler = [] (int sym, int uni) {
+      dialog::handleNavigation(sym, uni);
+      int lid;
+      if(uni >= 'a' && uni <= 'z') lid = uni - 'a';
+      else if(uni >= 'A' && uni <= 'Z') lid = 26 + uni - 'A';
+      else lid = -1;
+      
+      if(lid >= 0) lid += euperpage * eupage;
+      
+      if(uni == '5') 
+        ewhichscreen ^= 3;
+      else if(uni == '-' || uni == PSEUDOKEY_WHEELUP || uni == PSEUDOKEY_WHEELDOWN) {
+        eupage++;
+        if(eupage * euperpage >= size(landlist)) eupage = 0;
+        }
+      else if(uni == '1') {
+        if(chaosUnlocked) {
+          restartGame('C');
+          pushScreen(showEuclideanMenu);
+          }
+        }
+      else if(lid >= 0 && lid < size(landlist)) {
+        eLand nland = landlist[lid];
+        if(landvisited[nland]) {
+          specialland = nland;
+          restartGame(tactic::on ? 't' : 0);
+          pushScreen(showEuclideanMenu);
+          }
+        }
+      else if(uni == '2' || sym == SDLK_F1) gotoHelp(euchelp);
+      else if(doexiton(sym, uni)) popScreen();
+      };
+    }
+  
+  }
+
+void runGeometryExperiments() {
+  specialland = getLandForList(cwt.c);
+  pushScreen(showEuclideanMenu);
+  }
+
diff --git a/graph.cpp b/graph.cpp
index f2311d52..45eb4216 100644
--- a/graph.cpp
+++ b/graph.cpp
@@ -3067,6 +3067,7 @@ bool dodrawcell(cell *c) {
     if(c->mpdist > 7 && !cheater) return false;
     // always show on the torus rug
     if(rug::rugged && torus) return true;
+    if(cmode & sm::TORUSCONFIG) return true;
     // in the Yendor Challenge, scrolling back is forbidden
     if(c->cpdist > 7 && (yendor::on && !cheater)) return false;
     // (incorrect comment) too far, no bugs nearby
@@ -3343,6 +3344,14 @@ void drawcell(cell *c, transmatrix V, int spinv, bool mirrored) {
         PPR_TEXT); */
       queuestr(V, (cd > 9 ? .6 : 1) * .2, label, 0xFF000000 + distcolors[cd&7], 1);
       }
+    
+    if(cmode & sm::TORUSCONFIG) {
+      using namespace torusconfig;
+      int cd = torus_cx * dx + torus_cy * newdy;
+      cd %= newqty; if(cd<0) cd += newqty;
+      string label = its(cd);
+      queuestr(V, cd ? .2 : .6, label, cd == 0 ? 0xFFFF0040 : 0xFFFFFFD0, 1);
+      }
 
     asciicol = wcol;
     
diff --git a/hyper.h b/hyper.h
index a315ebbc..c1e09496 100644
--- a/hyper.h
+++ b/hyper.h
@@ -1443,6 +1443,7 @@ namespace sm {
   static const int CENTER = 1024;
   static const int A3 = 2048; // affects poly
   static const int ZOOMABLE = 4096;
+  static const int TORUSCONFIG = 8192;
   };
 
 namespace linepatterns {
diff --git a/hypgraph.cpp b/hypgraph.cpp
index f4f84283..2b8444db 100644
--- a/hypgraph.cpp
+++ b/hypgraph.cpp
@@ -390,6 +390,10 @@ transmatrix eumovedir(int d) {
   return eumove(0,0);
   }
 
+ld matrixnorm(const transmatrix& Mat) {
+  return Mat[0][2] * Mat[0][2] + Mat[1][2] * Mat[1][2];
+  }
+  
 void drawEuclidean() {
   DEBB(DF_GRAPH, (debugfile,"drawEuclidean\n"));
   eucoord px=0, py=0;
@@ -402,18 +406,20 @@ void drawEuclidean() {
     pid = decodeId(centerover->master);
   else
     decodeMaster(centerover->master, px, py);
-
+    
   int minsx = mindx-1, maxsx=maxdx+1, minsy=mindy-1, maxsy=maxdy+1;
   mindx=maxdx=mindy=maxdy=0;
   
-  static ld centerd;
-  
   transmatrix View0 = View;
   
   ld cellrad = vid.radius / (EUCSCALE + vid.alphax);
   
+  ld centerd = matrixnorm(View0);
+  
   for(int dx=minsx; dx<=maxsx; dx++)
   for(int dy=minsy; dy<=maxsy; dy++) {
+    torusconfig::torus_cx = dx;
+    torusconfig::torus_cy = dy;
     reclevel = eudist(dx, dy);
     cell *c;
     transmatrix Mat;
@@ -432,9 +438,8 @@ void drawEuclidean() {
     Mat = View0 * Mat;
     
     if(torus) {
-      ld locald = (Mat[0][2] * Mat[0][2] + Mat[1][2] * Mat[1][2]);
-      if(c == centerover) centerd = locald;
-      else if(locald < centerd) centerd = locald, centerover = c, View = View0 * eumove(dx, dy); 
+      ld locald = matrixnorm(Mat);
+      if(locald < centerd) centerd = locald, centerover = c, View = View0 * eumove(dx, dy);
       }
     
     // Mat[0][0] = -1;
diff --git a/menus.cpp b/menus.cpp
index 18f186fe..626527e8 100644
--- a/menus.cpp
+++ b/menus.cpp
@@ -305,6 +305,12 @@ void showMainMenu() {
 
 // -- display modes --
 
+void editScale() {
+  dialog::editNumber(vid.scale, .001, 1000, .1, 1, XLAT("scale factor"), 
+    XLAT("Scale the displayed model."));
+  dialog::scaleLog();
+  }
+
 void showDisplayMode() {
   cmode = sm::SIDE;
   gamescreen(0);
@@ -355,11 +361,7 @@ void showDisplayMode() {
   
     if(xuni == 'p') projectionDialog();
     
-    if(xuni == 'z') {
-      dialog::editNumber(vid.scale, .001, 1000, .1, 1, XLAT("scale factor"), 
-        XLAT("Scale the displayed model."));
-      dialog::scaleLog();
-      }
+    if(xuni == 'z') editScale();
     
     if(xuni == 'm') { vid.monmode += 60 + (shiftmul > 0 ? 1 : -1); vid.monmode %= 6; }
   
@@ -543,244 +545,6 @@ void showChangeMode() {
     };
   }
 
-// -- geometry menu --
-
-int eupage = 0;
-int euperpage = 21;
-
-const char *curvenames[8] = {
-  "0", "1", "2", "extremely hyperbolic", "strongly hyperbolic", "strongly hyperbolic", "moderately hyperbolic", "weakly hyperbolic"
-  };
-
-string euchelp =
-  "If you want to know how much the gameplay is affected by the "
-  "hyperbolic geometry in HyperRogue, this mode is for you!\n\n"
-  
-  "You can try many different geometries here. We start by gluing "
-  "n-gons in such a way that k of them meet in every vertex. "
-  "Depending on n and k, this either folds into a sphere, unfolds into a plane, "
-  "or requires a hyperbolic space. The result may be then 'truncated' by "
-  "replacing each vertex by a 2k-gon. Furthermore, you can play "
-  "with quotient geometries. For example, the elliptic geometry is "
-  "obtained from the sphere by making the antipodes be the same point, "
-  "so you return to the same spot (but as a mirror image) after going there. "
-  "Have fun experimenting! "
-  "Achievements and leaderboards do not work in geometry experiments, "
-  "except some specific ones.\n\n"
-  "In standard geometry (truncated or not), you can play the full game, but in other geometries "
-  "you select a particular land. Lands are unlocked by visiting them in this "
-  "session, or permanently by collecting 25 treasure. Try Crossroads in Euclidean "
-  "or chaos mode in non-standard non-quotient hyperbolic to visit many lands. "
-  "Highlights:\n"
-  "* Crystal World and Warped Coast can be understood as extra geometries.\n"
-  "* Halloween is specially designed for spherical geometry.\n"
-  "* To see the difference, try Hunting Grounds in Euclidean -- it is impossible.\n";
-
-int ewhichscreen = 2;
-
-void showEuclideanMenu() {
-  cmode = sm::SIDE;
-  gamescreen(0);  
-  int s = vid.fsize;
-  if(cheater) for(int i=0; i<landtypes; i++) landvisited[i] = true;
-  for(int i=0; i<landtypes; i++)
-    if(hiitemsMax(treasureType(eLand(i))) >= 25) landvisited[i] = true;
-  landvisited[laCrossroads] = true;
-  landvisited[laIce] = true;
-  landvisited[laHunting] = true;
-  landvisited[laMirrorOld] = true;
-  landvisited[laPrincessQuest] = cheater || princess::everSaved;
-  landvisited[laWildWest] = true;
-  landvisited[laHalloween] = true;
-  landvisited[laWarpCoast] = true;
-  landvisited[laGraveyard] = true;
-  landvisited[laDual] = true;
-  landvisited[laCA] = true;
-  // for(int i=2; i<lt; i++) landvisited[i] = true;
-  
-  if(geometry == gNormal || ewhichscreen == 2) {
-    dialog::init(XLAT("experiment with geometry"));
-    int ts = ginf[geometry].sides;
-    int tv = ginf[geometry].vertex;
-    int tq = ginf[geometry].quotientstyle;
-    int nom = (nontruncated ? tv : tv+ts) * ((tq & qELLIP) ? 2 : 4);
-    int denom = (2*ts + 2*tv - ts * tv);
-    
-    dialog::addSelItem(XLAT("land"), XLAT1(linf[specialland].name), '5');
-    dialog::addBreak(50);
-
-    for(int i=0; i<gGUARD; i++)
-      dialog::addBoolItem(XLAT(ginf[i].name), geometry == i, 'a'+i);
-    
-    dialog::addBreak(50);
-  
-    if(ts == 6 && tv == 3)
-      dialog::addSelItem(XLAT("truncated"), XLAT("does not matter"), 't');
-    else
-      dialog::addBoolItem(XLAT("truncated"), !nontruncated, 't');
-  
-    dialog::addBreak(50);
-  
-    int worldsize = denom ? nom/denom : 0;
-    if(tq & qTORUS) worldsize = torusconfig::qty;
-    if(tq & qZEBRA) worldsize = nontruncated ? 12 : 40;
-    if(tq & qFIELD) {
-      worldsize = size(currfp.matrices) / ts;
-      if(!nontruncated) worldsize = ((ts+tv)*worldsize) / tv;
-      }
-  
-    dialog::addSelItem(XLAT("sides per face"), its(ts), 0);
-    dialog::addSelItem(XLAT("faces per vertex"), its(tv), 0);
-  
-    string qstring = "none";
-    if(tq & qZEBRA) qstring = "zebra";
-  
-    else if(tq & qFIELD) qstring = "field";
-  
-    else if(tq & qELLIP) qstring = "torus";
-  
-    else if(tq & qTORUS) qstring = "torus";
-  
-    dialog::addSelItem(XLAT("quotient space"), XLAT(qstring), 0);
-  
-    dialog::addSelItem(XLAT("size of the world"), 
-      worldsize < 0 ? "exp(∞)*" + (nom%denom ? its(nom)+"/"+its(-denom) : its(-worldsize)): 
-      worldsize == 0 ? "∞" :
-      its(worldsize),
-      '3');
-    
-    switch(ginf[geometry].cclass) {
-      case 0:
-        dialog::addSelItem(XLAT("Curvature"), XLAT("hyperbolic"), 0);
-        break;
-      
-      case 1: 
-        dialog::addSelItem(XLAT("Curvature"), XLAT("flat"), 0);
-        break;
-      
-      case 2:
-        dialog::addSelItem(XLAT("Curvature"), XLAT("spherical"), 0);
-        break;
-      }
-    
-    if(sphere) 
-      dialog::addBoolItem(XLAT("stereographic/orthogonal"), vid.alpha>10, '1');
-    else
-      dialog::addBoolItem(XLAT("Poincaré/Klein"), vid.alpha>.5, '1');
-    dialog::addItem(XLAT("help"), SDLK_F1);  
-    dialog::addItem(XLAT("back"), '0');  
-    dialog::display();
-  
-    keyhandler = [] (int sym, int uni) {
-      dialog::handleNavigation(sym, uni);
-      if(uni >= 'a' && uni < 'a'+gGUARD) {
-        targetgeometry = eGeometry(uni - 'a');
-        restartGame(geometry == targetgeometry ? 0 : 'g');
-        pushScreen(showEuclideanMenu);
-        }
-      else if(uni == 't') {
-        if(!euclid) {
-          restartGame('7');
-          pushScreen(showEuclideanMenu);
-          }
-        }
-      else if(uni == '2' || sym == SDLK_F1) gotoHelp(euchelp);
-      else if(uni == '3') { viewdists = !viewdists; if(viewdists) popScreenAll(); }
-      else if(uni == '1' && !euclid) {
-        if(sphere) {
-          if(vid.alpha < 10) { vid.alpha = 999; vid.scale = 998; }
-          else {vid.alpha = 1; vid.scale = .4; }
-          }
-        else {
-          if(vid.alpha > .5) { vid.alpha = 0; vid.scale = 1; }
-          else {vid.alpha = 1; vid.scale = 1; }
-          }
-        }
-      else if(uni == '5')
-        ewhichscreen ^= 3;
-      else if(doexiton(sym, uni))
-        popScreen();
-      };
-    }
-  else {
-    dialog::init(XLAT("experiment with geometry"));
-    string truncatenames[2] = {" (t)", " (n)"};
-  
-    dialog::addSelItem(XLAT("geometry"), XLAT(ginf[geometry].name) + XLAT(truncatenames[nontruncated]), '5');
-    dialog::addBreak(50);
-    
-    generateLandList(isLandValid);
-    
-    for(int i=0; i<euperpage; i++) {
-      if(euperpage * eupage + i >= size(landlist)) { dialog::addBreak(100); break; }
-      eLand l = landlist[euperpage * eupage + i];
-      char ch;
-      if(i < 26) ch = 'a' + i;
-      else ch = 'A' + (i-26);
-      string validclasses[4] = {"", " (½)", "", " (!)"};
-      string s = XLAT1(linf[l].name);
-
-      if(landvisited[l]) {
-        dialog::addBoolItem(s, l == specialland, ch);
-        }
-      else {
-        dialog::addSelItem(s, XLAT("(locked)"), ch);
-        }
-      
-      dialog::lastItem().color = linf[l].color;
-      dialog::lastItem().value += validclasses[isLandValid(l)];
-      }
-    dialog::addBreak(50);
-    if(chaosUnlocked && !quotient && !euclid && !sphere)
-      dialog::addItem(XLAT("Chaos mode"), '1');
-    dialog::addItem(XLAT("next page"), '-');
-    
-    dialog::addItem(XLAT("help"), SDLK_F1);  
-    dialog::addItem(XLAT("back"), '0');
-    dialog::display();
-  
-    vid.fsize = s;
-    keyhandler = [] (int sym, int uni) {
-      dialog::handleNavigation(sym, uni);
-      int lid;
-      if(uni >= 'a' && uni <= 'z') lid = uni - 'a';
-      else if(uni >= 'A' && uni <= 'Z') lid = 26 + uni - 'A';
-      else lid = -1;
-      
-      if(lid >= 0) lid += euperpage * eupage;
-      
-      if(uni == '5') 
-        ewhichscreen ^= 3;
-      else if(uni == '-' || uni == PSEUDOKEY_WHEELUP || uni == PSEUDOKEY_WHEELDOWN) {
-        eupage++;
-        if(eupage * euperpage >= size(landlist)) eupage = 0;
-        }
-      else if(uni == '1') {
-        if(chaosUnlocked) {
-          restartGame('C');
-          pushScreen(showEuclideanMenu);
-          }
-        }
-      else if(lid >= 0 && lid < size(landlist)) {
-        eLand nland = landlist[lid];
-        if(landvisited[nland]) {
-          specialland = nland;
-          restartGame(tactic::on ? 't' : 0);
-          pushScreen(showEuclideanMenu);
-          }
-        }
-      else if(uni == '2' || sym == SDLK_F1) gotoHelp(euchelp);
-      else if(doexiton(sym, uni)) popScreen();
-      };
-    }
-  
-  }
-
-void runGeometryExperiments() {
-  specialland = getLandForList(cwt.c);
-  pushScreen(showEuclideanMenu);
-  }
-
 bool showstartmenu;
 
 bool showHalloween() {