From 4b1b0516f3cb1815d992b3cee08c319b7b00bb28 Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Sun, 11 Apr 2021 22:15:40 +0200
Subject: [PATCH] choice of the land structure

---
 achievement.cpp   |  21 +++--
 bigstuff.cpp      | 221 ++++++++++++++++++++++++++--------------------
 binary-tiling.cpp |   4 +-
 celldrawer.cpp    |  10 +--
 complex.cpp       |  18 ++--
 config.cpp        |  11 +--
 debug.cpp         |  16 +---
 environment.cpp   |   2 +-
 geom-exp.cpp      |  15 +---
 graph.cpp         |   2 +-
 help.cpp          |   2 +-
 hyper.h           |   2 +-
 inventory.cpp     |   6 +-
 items.cpp         |  12 +--
 landgen.cpp       | 107 +++++++++++-----------
 landlock.cpp      | 140 +++++++++++++++++++++--------
 legacy.cpp        |  43 ++++++++-
 mapeffects.cpp    |   2 +-
 menus.cpp         |  64 +++++++++-----
 monstergen.cpp    |   2 +-
 multigame.cpp     |   2 +-
 orbgen.cpp        |   4 +-
 pattern2.cpp      |   5 ++
 pcmove.cpp        |   2 +-
 quit.cpp          |   2 +-
 scores.cpp        |   2 +-
 system.cpp        |  61 ++++++-------
 yendor.cpp        |  12 ++-
 28 files changed, 473 insertions(+), 317 deletions(-)

diff --git a/achievement.cpp b/achievement.cpp
index 97cd96c6..6cdd3c5e 100644
--- a/achievement.cpp
+++ b/achievement.cpp
@@ -125,7 +125,12 @@ EX bool wrongMode(char flags) {
 #if CAP_TOUR
   if(tour::on) return true;
 #endif
-  if((!!chaosmode) != (flags == rg::chaos)) return true;
+  if(flags == rg::special_geometry && !ls::single())
+    return true;
+  if(flags != rg::special_geometry && ineligible_starting_land)
+    return true;
+  if(flags == rg::chaos && !ls::std_chaos()) return true;
+  if(flags != rg::chaos && flags != rg::special_geometry && !ls::nice_walls()) return true;
   if((numplayers() > 1) != (flags == rg::multi)) return true;
   return false;
   }
@@ -610,7 +615,10 @@ EX void achievement_score(int cat, int number) {
     if(geometry != gSphere && geometry != gElliptic)
       return;
     }
-  else if(geometry) return;
+  else {
+    if(geometry) return;
+    if(ineligible_starting_land) return;
+    }
   if(CHANGED_VARIATION) return;
   if(randomPatternsMode) return;
   if(dual::state) return;
@@ -731,7 +739,8 @@ EX void achievement_final(bool really_final) {
   
   int specialcode = 0;
   if(shmup::on) specialcode++;
-  if(chaosmode) specialcode+=2;
+  if(ls::std_chaos()) specialcode+=2;
+  else if(!ls::nice_walls()) return;
   if(PURE) specialcode+=4;
   if(numplayers() > 1) specialcode+=8;
   if(inv::on) specialcode+=16;
@@ -742,6 +751,7 @@ EX void achievement_final(bool really_final) {
     return;
     }
 
+  if(ineligible_starting_land) return;
   if(geometry) return;
   if(NONSTDVAR) return;
   
@@ -828,7 +838,8 @@ EX void achievement_victory(bool hyper) {
   if(yendor::on) return;
   if(peace::on) return;
   if(tactic::on) return;
-  if(chaosmode) return;
+  if(!ls::nice_walls()) return;
+  if(!ineligible_starting_land) return;
   LATE( achievement_victory(hyper); )
   DEBB(DF_STEAM, ("after checks"))
 
@@ -904,7 +915,7 @@ EX string get_rich_presence_text() {
   if(geometry != gNormal || !BITRUNCATED) 
     res = res + full_geometry_name() + " ";
   
-  if(chaosmode) res += "chaos ";
+  if(ls::any_chaos()) res += land_structure_name(false) + " "; // TODO
   if(shmup::on) res += "shmup ";
   if(dual::state) res += "dual ";
   if(randomPatternsMode) res += "random ";
diff --git a/bigstuff.cpp b/bigstuff.cpp
index bd1b2e84..ba3dfbfa 100644
--- a/bigstuff.cpp
+++ b/bigstuff.cpp
@@ -480,7 +480,7 @@ EX cell *buildAnotherEquidistant(cell *c, int radius) {
   bool oc = c->land == laOcean;
   
   // else if(ctof(c) && hrand(10000) < 20 && !isCrossroads(c->land) && gold() >= 200)
-  if(oc && weirdhyperbolic && specialland == laCrossroads4 && buildBarrierNowall(c2, getNewLand(laOcean))) {
+  if(oc && ls::no_walls() && buildBarrierNowall(c2, getNewLand(laOcean))) {
     nowall = true;
     }
   else if(oc && pseudohept(c2) && gold() >= R200 && hrand(10) < 2 && buildBarrierNowall(c2, laCrossroads4)) {
@@ -488,7 +488,7 @@ EX cell *buildAnotherEquidistant(cell *c, int radius) {
     // raiseBuggyGeneration(c2, "check");
     // return;
     }
-  else if(!weirdhyperbolic) buildBarrier(c2, bd);
+  else if(ls::nice_walls()) buildBarrier(c2, bd);
   //printf("building barrier II\n");
   if(hasbardir(c2)) extendBarrier(c2);
 
@@ -571,7 +571,7 @@ EX void buildEquidistant(cell *c) {
     } */
   if(sphere || euclid) return;
   eLand b = c->land;
-  if(chaosmode && !inmirror(b)) return;
+  if(ls::any_chaos() && !inmirror(b)) return;
   if(!b) { 
     printf("land missing at %p\n", hr::voidp(c)); 
     describeCell(c);
@@ -815,12 +815,10 @@ EX void buildEquidistant(cell *c) {
       }
     }
   
-  bool chance = true;
-  if(weirdhyperbolic) {
-    chance = false;
-    if(specialland == laCrossroads4)
-      chance = hrand(100) < 10;
-    }
+  bool chance = 
+    ls::no_walls() ? (hrand(100) < 10) :
+    ls::nice_walls() ? true :
+    false;
   
   if(c->landparam > 30 && b == laOcean && !generatingEquidistant && !hybri && hrand(10) < 5 && chance) 
     buildAnotherEquidistant(c);
@@ -972,12 +970,12 @@ bool valid_wall_at(int c) {
   }
   
 EX eLand switchable(eLand nearland, eLand farland, int c) {
-  if(chaosmode) {
+  if(ls::std_chaos()) {
     if(hrand(6) == 0)
       return getNewLand(nearland);
     return nearland;
     }
-  else if(specialland == laCrossroads4) {
+  else if(ls::no_walls()) {
     if((dual::state && nearland == laCrossroads4) || hrand(15) == 0)
       return getNewLand(nearland);
     if(nearland == laCrossroads4 && (nonisotropic || hybri))
@@ -1017,15 +1015,15 @@ EX eLand getEuclidLand(int c) {
 
 EX void setLandSol(cell *c) {
   setland(c, specialland);
-  if(chaosmode) {
+  if(ls::std_chaos()) {
     setland(c, getEuclidLand(c->master->distance));
     return;
     }
-  switch(specialland) {
-    case laCrossroads4: case laCrossroads: case laCrossroads2:
-      setland(c, getEuclidLand(c->master->distance));
-      if(c->land == laBarrier && c->master->emeraldval % 3) c->wall = waBarrier;
-      break;
+  else if(ls::nice_walls()) {
+    setland(c, getEuclidLand(c->master->distance));
+    if(c->land == laBarrier && c->master->emeraldval % 3) c->wall = waBarrier;
+    }
+  switch(c->land) {
     case laTerracotta:
       if((c->master->distance & 15) == 1) {
         setland(c, laMercuryRiver);
@@ -1045,17 +1043,17 @@ EX void setLandHybrid(cell *c) {
     auto w = hybrid::get_where(c);
     auto d = w.second;
     
+    bool ps = PIU(pseudohept(w.first));
     setland(c, specialland);
-    if(chaosmode) {
-      setland(c, getEuclidLand(c->master->distance));
+    if(ls::any_nowall()) {
+      setland(c, getEuclidLand(d));
       return;
       }
-    bool ps = PIU(pseudohept(w.first));
-    switch(specialland) {
-      case laCrossroads4: case laCrossroads: case laCrossroads2:
-        setland(c, getEuclidLand(d));
-        if(c->land == laBarrier) c->wall = ps ? waNone : waBarrier;
-        break;
+    else if(ls::any_wall()) {
+      setland(c, getEuclidLand(d));
+      if(c->land == laBarrier) c->wall = ps ? waNone : waBarrier;
+      }
+    switch(c->land) {
       case laTerracotta:
         if((d & 15) == 1) {
           setland(c, laMercuryRiver);
@@ -1085,23 +1083,23 @@ EX void setLandHybrid(cell *c) {
 EX void setLandNil(cell *c) {
   setland(c, specialland);
   
-  if(chaosmode) {
+  if(ls::patched_chaos()) {
     int hash = (((c->master->zebraval + 4) >> 3) << 16) + ((c->master->emeraldval + 4) >> 3);
     auto& l = euland3_hash[hash];
     if(l == laNone) l = getNewLand(laNone);
     setland(c, l);
     return;
     }
-  
-  switch(specialland) {
-    case laCrossroads: case laCrossroads4:
-      setland(c, getEuclidLand(c->master->zebraval));
-      if(c->land == laBarrier && c->master->emeraldval % 3) c->wall = waBarrier;
-      break;
-    case laCrossroads2: 
-      setland(c, getEuclidLand(c->master->emeraldval));
-      if(c->land == laBarrier && c->master->zebraval % 3) c->wall = waBarrier;
-      break;
+  else if(ls::nice_walls()) {
+    setland(c, getEuclidLand(c->master->zebraval));
+    if(c->land == laBarrier && c->master->emeraldval % 3) c->wall = waBarrier;
+    }
+  else if(ls::no_walls()) {
+    setland(c, getEuclidLand(c->master->emeraldval));
+    if(c->land == laBarrier && c->master->zebraval % 3) c->wall = waBarrier;
+    }
+    
+  switch(c->land) {
     case laCrossroads3: {
       int ox = c->master->zebraval - 8;
       int oy = c->master->emeraldval - 8;
@@ -1144,17 +1142,17 @@ EX void setLandEuclid(cell *c) {
     }
   #endif
   setland(c, specialland);
-  if(specialland == laCrossroads4 || chaosmode) {
+  if(ls::any_nowall()) {
     auto co = euc2_coordinates(c);
     int y = co.second;
     c->land = getEuclidLand(y);
     }
-  if(specialland == laCrossroads) {
+  if(ls::any_wall()) {
     auto co = euc2_coordinates(c);
     int x = co.first, y = co.second;
     setland(c, getEuclidLand(y+2*x));
     }
-  if(specialland == laTerracotta) {
+  if(c->land == laTerracotta) {
     auto co = euc2_coordinates(c);
     int x = co.first, y = co.second;
     if(((y+2*x) & 15) == 1) {
@@ -1228,7 +1226,7 @@ EX void setLandEuclid(cell *c) {
       setland(c, laElementalWall);
       }
     }
-  if(specialland == laCrossroads3) {
+  if(c->land == laCrossroads3) {
     auto co = euc2_coordinates(c);
     int x = co.first, y = co.second;
     int y0 = euc::in(2,4) ? 2 * y - x : y; 
@@ -1269,46 +1267,42 @@ EX eLand get_euland3(int x) {
 
 EX void set_euland3(cell *c, int co10, int co11, int alt, int hash) {
 
-  if(chaosmode) {
+  if(ls::std_chaos()) {
     setland(c, get_euland3(gdiv(co10, 60)));
     }
   
-  else if(specialland == laCrossroads) {
+  else if(ls::nice_walls()) {
     eLand l1 = get_euland3(gdiv(co10, 360));
     eLand l2 = get_euland3(gdiv(co10+59, 360));
     if(l1 != l2 && hrand(100) < 75) setland(c, laBarrier);
     else setland(c, l1);
     }
 
-  else if(specialland == laCrossroads2) {
+  else if(ls::no_walls()) {
     setland(c, get_euland3(alt/4));
     }
 
-  else if(specialland == laCrossroads3) {
+  else if(ls::patched_chaos()) {
     auto& l = euland3_hash[hash];
     if(l == laNone) l = getNewLand(laBarrier);
     setland(c, l);
     }
 
-  else if(specialland == laCrossroads4) {
-    setland(c, get_euland3(gdiv(co10, 360)));
-    }
-  
-  else if(specialland == laElementalWall) {
+  if(c->land == laElementalWall) {
     setland(c, eLand(laEFire + ((co10 / 240)&1?0:2) + ((co11 / 240)&1?0:1)));
     }
   
-  if(specialland == laCamelot) {
+  if(c->land == laCamelot) {
     setland(c, laCrossroads);
     buildCamelot(c);
     }
 
-  if(specialland == laTerracotta) {
+  if(c->land == laTerracotta) {
     if(((alt&15) == 8) && hrand(100) < 90)
        c->wall = waMercury;
     }
 
-  if(among(specialland, laOcean, laIvoryTower, laDungeon, laEndorian)) {
+  if(among(c->land, laOcean, laIvoryTower, laDungeon, laEndorian)) {
     if(alt == 0)
       c->land = laCrossroads4;
     else if(alt > 0)
@@ -1317,7 +1311,7 @@ EX void set_euland3(cell *c, int co10, int co11, int alt, int hash) {
       c->landparam = -alt;
     }
   
-  if(specialland == laWarpCoast) {
+  if(c->land == laWarpCoast) {
     if(gmod(co10, 240) >= 120)
       c->land = laWarpSea;
     }
@@ -1325,9 +1319,11 @@ EX void set_euland3(cell *c, int co10, int co11, int alt, int hash) {
 
 // the main big stuff function
 
+EX bool easy_to_find_specialland = false;
+
 EX bool quickfind(eLand l) {
   if(l == cheatdest) return true;
-  if(l == specialland && (weirdhyperbolic || specialland != laIce || cheater)) return true;
+  if(l == specialland && easy_to_find_specialland) return true;
 #if CAP_TOUR
   if(tour::on && tour::quickfind(l)) return true;
 #endif
@@ -1363,8 +1359,7 @@ EX int wallchance(cell *c, bool deepOcean) {
     l == laCrossroads2 ? 10000 : 
     l == laCrossroads5 ? 10000 : 
     l == laCrossroads4 ? (weirdhyperbolic ? 5000 : 0) :
-    (l == laMirror && !yendor::generating) ? 6000 :
-    l == laTerracotta ? 250 :
+    (l == laMirror && !yendor::generating) ? 2500 :
     tactic::on ? 0 :
     racing::on ? 0 :
     l == laCaribbean ? 500 :
@@ -1433,36 +1428,61 @@ EX bool good_for_wall(cell *c) {
   }
 
 EX bool walls_not_implemented() {
+  if(sphere || quotient || nonisotropic || (kite::in() && !bt::in()) || experimental) return true;
   return WDIM == 3 && (cgflags & qIDEAL);
   }
-  
-EX void buildBigStuff(cell *c, cell *from) {
-  if(sphere || quotient || nonisotropic || (kite::in() && !bt::in()) || experimental) return;
-  if(chaosmode > 1) return;
+
+EX bool nice_walls_available() {
+  return (geometry == gNormal && (PURE || BITRUNCATED)) || (geometry == gEuclid && !(INVERSE | IRREGULAR));
+  }
+
+EX void build_walls(cell *c, cell *from) {
   bool deepOcean = deep_ocean_at(c, from);
   
   // if(weirdhyperbolic && c->land == laOcean) deepOcean = c->landparam >= 30;
   
   // buildgreatwalls
   
-  if(hybri) ;  /* Great Walls generated via the underlying geometry */
+  if(hybri) return;  /* Great Walls generated via the underlying geometry */
   
-  else if(walls_not_implemented()); // walls not implemented here
+  if(walls_not_implemented()) return; // walls not implemented here  
+
+  if(ls::chaoticity() >= 60) return;
   
-  else if(geometry == gNormal && celldist(c) < 3 && !GOLDBERG) {
+  if(nice_walls_available()) {
+    if(ctof(c) && c->land == laMirror && !yendor::generating && hrand(I10000) < 6000) {
+      int bd = 2 + hrand(2) * 3;    
+      buildBarrier(c, bd, laMirrored); 
+      return;
+      }
+  
+    if(ctof(c) && c->land == laTerracotta && hrand(I10000) < 200) {
+      int bd = 2 + hrand(2) * 3;    
+      buildBarrier(c, bd, laMirrored); 
+      return;
+      }
+    }
+  
+  if(ls::single()) return;
+    
+  if(geometry == gNormal && celldist(c) < 3 && !GOLDBERG) {
     if(top_land && c == cwt.at->master->move(3)->c7) {
       buildBarrierStrong(c, 6, true, top_land);
       }
     }
   
-  else if(chaosmode) {
-    if(good_for_wall(c) && hrand(10000) < 9000 && c->land && !inmirror(c) && buildBarrierNowall(c, getNewLand(c->land))) 
-      {}
-    else if(ctof(c) && c->land == laMirror && hrand(10000) < 2000 && !weirdhyperbolic) {
-      int bd = 2 + hrand(2) * 3;
-      buildBarrier(c, bd, laMirrored); 
+  else if(ls::wall_chaos()) {
+    if(good_for_wall(c) && hrand(10000) < 9000 && c->land && !inmirror(c)) {
+      int bd = 2 + hrand(2) * 3;    
+      buildBarrier(c, bd); 
+      return;
       }
     }
+
+  else if(ls::std_chaos()) {
+    if(good_for_wall(c) && hrand(10000) < 9000 && c->land && !inmirror(c) && buildBarrierNowall(c, getNewLand(c->land))) 
+      return;
+    }
   
   else if(good_for_wall(c) && isWarpedType(c->land) && hrand(10000) < 3000 && c->land && 
     buildBarrierNowall(c, eLand(c->land ^ laWarpSea ^ laWarpCoast))) ;
@@ -1481,7 +1501,7 @@ EX void buildBigStuff(cell *c, cell *from) {
     buildBarrierNowall(c, laCrossroads4) ;
     }
   
-  else if(weirdhyperbolic && specialland == laCrossroads4 && /*pseudohept(c) &&*/ hrand(I10000 /4) < wallchance(c, deepOcean) && gp_wall_test()) {
+  else if(ls::no_walls() && hrand(I10000 /4) < wallchance(c, deepOcean) && gp_wall_test()) {
     buildBarrierNowall(c, getNewLand(c->land));
     }
   
@@ -1496,13 +1516,13 @@ EX void buildBigStuff(cell *c, cell *from) {
   else if(S3 >= OINF && c->land && hrand(I10000) < wallchance(c, deepOcean) && c->bardir != NOBARRIERS)
     buildBarrierNowall(c, getNewLand(c->land));
   
-  else if(weirdhyperbolic) ; // non-Nowall barriers not implemented yet in weird hyperbolic
+  else if(!nice_walls_available()) ; // non-Nowall barriers not implemented yet in weird hyperbolic
   
   else if(c->land == laCrossroads2 && BITRUNCATED)
     buildCrossroads2(c);
   
   #if CAP_FIELD
-  else if(c->land == laPrairie && c->LHU.fi.walldist == 0 && !euclid) {
+  else if(c->land == laPrairie && c->LHU.fi.walldist == 0 && !euclid && ls::nice_walls()) {
     for(int bd=0; bd<7; bd++) {
       int fval2 = createStep(c->master, bd)->fieldval;
       int wd = currfp_gmul(fval2, currfp_inverses(c->fval-1));
@@ -1514,7 +1534,7 @@ EX void buildBigStuff(cell *c, cell *from) {
     }
   #endif
 
-  else if(ctof(c) && c->land && hrand(I10000) < wallchance(c, deepOcean))
+  else if(ctof(c) && c->land && ls::nice_walls() && hrand(I10000) < wallchance(c, deepOcean))
   {
     
     int bd = 2 + hrand(2) * 3;
@@ -1524,25 +1544,33 @@ EX void buildBigStuff(cell *c, cell *from) {
     /* int bd = 2;      
     buildBarrier4(c, bd, 0, getNewLand(c->land), c->land); */
     }
-      
-  if((!chaosmode) && bearsCamelot(c->land) && is_master(c) && !bt::in() && 
-    #if MAXMDIM >= 4
-    !(hyperbolic && WDIM == 3 && !reg3::in_rule()) && 
-    #endif
-    (quickfind(laCamelot) || peace::on || (hrand(I2000) < (c->land == laCrossroads4 ? 800 : 200) && horo_ok() && 
-    items[itEmerald] >= U5 && !tactic::on && !racing::on))) {
-    int rtr = newRoundTableRadius();
-    heptagon *alt = createAlternateMap(c, rtr+(hyperbolic && WDIM == 3 ? 11 : 14), hsOrigin);
-    if(alt) {
-      alt->emeraldval = rtr;
-      alt->fiftyval = c->land;
-      }
-    }
+  }
 
-  if(!chaosmode) {
+EX void build_horocycles(cell *c, cell *from) {
+
+  bool deepOcean = deep_ocean_at(c, from);
+
+  if(!ls::any_order() && !ls::single()) return;
+  
+  if(ls::single() && !among(specialland, laTemple, laMountain, laClearing, laStorms, laWhirlpool, laCaribbean, laCanvas, laPrincessQuest, laCamelot))
+    return;
   
     // buildbigstuff
 
+    if(ls::any_order() && bearsCamelot(c->land) && is_master(c) && !bt::in() && 
+      #if MAXMDIM >= 4
+      !(hyperbolic && WDIM == 3 && !reg3::in_rule()) && 
+      #endif
+      (quickfind(laCamelot) || peace::on || (hrand(I2000) < (c->land == laCrossroads4 ? 800 : 200) && horo_ok() && 
+      items[itEmerald] >= U5 && !tactic::on && !racing::on))) {
+      int rtr = newRoundTableRadius();
+      heptagon *alt = createAlternateMap(c, rtr+(hyperbolic && WDIM == 3 ? 11 : 14), hsOrigin);
+      if(alt) {
+        alt->emeraldval = rtr;
+        alt->fiftyval = c->land;
+        }
+      }
+
     if(c->land == laRlyeh && ctof(c) && horo_ok() && 
       (quickfind(laTemple) || peace::on || (hrand(I2000) < 100 && 
       items[itStatue] >= U5 && !randomPatternsMode && 
@@ -1593,13 +1621,18 @@ EX void buildBigStuff(cell *c, cell *from) {
       celllister cl(c, 5, 1000000, NULL);
       for(cell *c: cl.lst) if(c->master->alt) currentmap->generateAlts(c->master);
       }
-    }
+  }
   
-  if(hasbardir(c)) extendBarrier(c);
+EX void buildBigStuff(cell *c, cell *from) {
+  build_walls(c, from);
+  
+  build_horocycles(c, from);
+
+  if(hasbardir(c)) extendBarrier(c);  
   }
 
 EX bool openplains(cell *c) {
-  if(chaosmode) {
+  if(ls::any_chaos()) {
     forCellEx(c2, c) if(c2->land != laHunting) return false;
     return true;
     }
@@ -1774,7 +1807,7 @@ EX void moreBigStuff(cell *c) {
         }
       }        
 
-  if(chaosmode && c->land == laTemple) {
+  if(ls::any_chaos() && c->land == laTemple) {
     for(int i=0; i<c->type; i++)
       if(pseudohept(c) && c->move(i) && c->move(i)->land != laTemple)
         c->wall = waColumn;
@@ -1782,7 +1815,7 @@ EX void moreBigStuff(cell *c) {
   
   else if((c->land == laRlyeh && !euclid) || c->land == laTemple) if(!(bt::in() && specialland != laTemple && c->land == laRlyeh)) {
     if(eubinary || in_s2xe() || (c->master->alt && (tactic::on || masterAlt(c) <= horo_gen_distance()))) {
-      if(!eubinary && !chaosmode) currentmap->generateAlts(c->master);
+      if(!eubinary && !ls::any_chaos()) currentmap->generateAlts(c->master);
       preventbarriers(c);
       int d = celldistAlt(c);
       if(d <= 0) {
@@ -1912,7 +1945,7 @@ EX vector<eLand> currentlands;
 
 EX void pregen() {
   currentlands.clear();
-  if(chaosmode > 1)
+  if(ls::any_chaos() && !ls::std_chaos())
     for(eLand l: land_over)
       if(landUnlocked(l) && isLandIngame(l)) 
         currentlands.push_back(l);
diff --git a/binary-tiling.cpp b/binary-tiling.cpp
index f2a7d2d4..871dfc47 100644
--- a/binary-tiling.cpp
+++ b/binary-tiling.cpp
@@ -108,13 +108,13 @@ EX namespace bt {
     if(!parent->emeraldval) parent->emeraldval = currentmap->gamestart()->land;
     eLand z = eLand(parent->emeraldval);
     int chance = 0;
-    if(specialland == laCrossroads4 || parent->emeraldval == laCrossroads4) {
+    if(ls::no_walls() || parent->emeraldval == laCrossroads4) {
       eLand x = parent->c7->land;
       parent->c7->land = z;
       chance = wallchance(parent->c7, deep_ocean_at(parent->c7, parent->c7));
       parent->c7->land = x;
       }
-    if(chaosmode) chance = 1000;
+    if(ls::std_chaos()) chance = 1000;
     if(chance && hrand(40000) < chance)
       h->emeraldval = getNewLand(z);
     else
diff --git a/celldrawer.cpp b/celldrawer.cpp
index 388010bf..a0351d0d 100644
--- a/celldrawer.cpp
+++ b/celldrawer.cpp
@@ -100,11 +100,11 @@ void celldrawer::setcolors() {
     if(c->land == laOcean)
       fcol = 
         #if CAP_FIELD
-        (c->landparam > 25 && !chaosmode) ? ( 
+        (c->landparam > 25 && !ls::any_chaos()) ? ( 
           0x90 + 8 * sintick(1000, windmap::windcodes[windmap::getId(c)] / 256.)
           ) : 
         #endif
-        0x1010C0 + int(32 * sintick(500, (chaosmode ? c->CHAOSPARAM : c->landparam)*.75/M_PI));
+        0x1010C0 + int(32 * sintick(500, (ls::any_chaos() ? c->CHAOSPARAM : c->landparam)*.75/M_PI));
     else if(c->land == laOceanWall)
       fcol = 0x2020FF;
     else if(c->land == laVariant)
@@ -295,7 +295,7 @@ void celldrawer::setcolors() {
       break;
     case laTemple: {
       int d = (eubinary||c->master->alt) ? celldistAlt(c) : 99;
-      if(chaosmode)
+      if(ls::any_chaos())
         fcol = 0x405090;
       else if(d % temple_layer_size() == 0)
         fcol = gradient(0x304080, winf[waColumn].color, 0, 0.5, 1);
@@ -445,7 +445,7 @@ void celldrawer::setcolors() {
       break;
     
     case laOcean:
-      if(chaosmode)
+      if(ls::any_chaos())
         fcol = gradient(0xD0A090, 0xD0D020, 0, c->CHAOSPARAM, 30);
       else
         fcol = gradient(0xD0D090, 0xD0D020, -1, sin((double) c->landparam), 1);
@@ -1999,7 +1999,7 @@ void celldrawer::draw_wall_full() {
       
 #if CAP_SHAPES
     // floor
-    if(GDIM == 2 && (c->land != laRose || chaosmode)) {
+    if(GDIM == 2 && (c->land != laRose || ls::any_chaos())) {
       int rd = rosedist(c);
       if(rd == 1) 
         draw_floorshape(c, mmscale(V, cgi.SLEV[2]), cgi.shRoseFloor, 0x80406040, PPR::LIZEYE);
diff --git a/complex.cpp b/complex.cpp
index 33fdea96..01a9f44b 100644
--- a/complex.cpp
+++ b/complex.cpp
@@ -1986,11 +1986,11 @@ EX namespace hive {
     cellwalker bf(c, gdir);
     int radius = 9;
     if(getDistLimit() <= 6) radius = 6;
-    if(chaosmode) radius = 5;
-    if(chaosmode && getDistLimit() <= 5) radius = 4;
+    if(ls::any_chaos()) radius = 5;
+    if(ls::any_chaos() && getDistLimit() <= 5) radius = 4;
     if(getDistLimit() <= 3) radius = 3;
 
-    for(int i=(chaosmode?0:2); i<radius; i++) 
+    for(int i=(ls::any_chaos()?0:2); i<radius; i++) 
       bf += revstep;
     cell *citycenter = bf.at;
     buginfo.clear();
@@ -2370,7 +2370,7 @@ EX void livecaves() {
         else if(w == waDeadTroll2) hv -= 3;
         else if(w == waPetrified || w == waPetrifiedBridge) hv -= 2;
         else if(w == waVinePlant) hv--;
-        else if(chaosmode && c2->land != laCaves && c2->land != laEmerald) ;
+        else if(ls::any_chaos() && c2->land != laCaves && c2->land != laEmerald) ;
         else if(c2->land == laTrollheim) ; // trollheim floor does not count
         else if(w != waBarrier) hv += 5;
         
@@ -3107,9 +3107,9 @@ EX namespace prairie {
     c->LHU.fi.walldist = 8;
     c->LHU.fi.walldist2 = 8;
 
-     if(chaosmode) {
-       c->LHU.fi.rval = 0;
-       }    
+    if(ls::any_chaos()) {
+      c->LHU.fi.rval = 0;
+      }    
     else if(quotient) { // fix cylinder
       c->LHU.fi.rval = 0;
       }
@@ -3301,7 +3301,7 @@ EX namespace prairie {
     }
           
   EX void move() {
-    if(chaosmode) return;
+    if(ls::any_chaos()) return;
     manual_celllister cl;
     for(int i=0; i<isize(dcal); i++) {
       cell *c = dcal[i];
@@ -3613,7 +3613,7 @@ EX namespace windmap {
       }
     
     int tries = 0;
-    int maxtries = specialland == laVolcano || specialland == laBlizzard || chaosmode ? 20 : 1;
+    int maxtries = specialland == laVolcano || specialland == laBlizzard || ls::any_chaos() ? 20 : 1;
     tryagain:
 
     for(int i=0; i<N; i++) windcodes[i] = hrand(256);
diff --git a/config.cpp b/config.cpp
index e60d792e..3ac7a2c9 100644
--- a/config.cpp
+++ b/config.cpp
@@ -832,7 +832,7 @@ EX void initConfig() {
   addsaverenum(geometry, "mode-geometry");
   addsaver(shmup::on, "mode-shmup", false);
   addsaver(hardcore, "mode-hardcore", false);
-  addsaver(chaosmode, "mode-chaos");
+  addsaverenum(land_structure, "mode-chaos");
   #if CAP_INV
   addsaver(inv::on, "mode-Orb Strategy");
   #endif
@@ -1053,7 +1053,7 @@ EX void initConfig() {
   }
 
 EX bool inSpecialMode() {
-  return chaosmode || !BITRUNCATED || peace::on || 
+  return !ls::nice_walls() || ineligible_starting_land || !BITRUNCATED || peace::on || 
   #if CAP_TOUR
     tour::on ||
   #endif
@@ -1070,7 +1070,7 @@ EX bool have_current_settings() {
 #if CAP_TOUR
   if(tour::on) modecount += 10;
 #endif
-  if(chaosmode) modecount += 10;
+  if(!ls::nice_walls()) modecount += 10;
   if(!BITRUNCATED) modecount += 10;
   if(peace::on) modecount += 10;
   if(yendor::on) modecount += 10;
@@ -1113,7 +1113,9 @@ EX void resetModes(char leave IS('c')) {
     }
   if(shmup::on != (leave == rg::shmup)) stop_game_and_switch_mode(rg::shmup);
   if(inv::on != (leave == rg::inv)) stop_game_and_switch_mode(rg::inv);
-  if(chaosmode != (leave == rg::chaos)) stop_game_and_switch_mode(rg::chaos);
+
+  if(leave == rg::chaos && !ls::std_chaos()) stop_game_and_switch_mode(rg::chaos);
+  if(leave != rg::chaos && !ls::nice_walls()) stop_game_and_switch_mode(rg::chaos);
 
   if((!!dual::state) != (leave == rg::dualmode)) stop_game_and_switch_mode(rg::dualmode);
 
@@ -3189,7 +3191,6 @@ EX int read_gamemode_args() {
     stop_game_and_switch_mode(rg::nothing);
     multi::players = argi();
     }
-  TOGGLE('C', chaosmode, stop_game_and_switch_mode(rg::chaos))
   TOGGLE('S', shmup::on, stop_game_and_switch_mode(rg::shmup))
   TOGGLE('H', hardcore, switchHardcore())
   TOGGLE('R', randomPatternsMode, stop_game_and_switch_mode(rg::randpattern))
diff --git a/debug.cpp b/debug.cpp
index b1a117af..8d88461d 100644
--- a/debug.cpp
+++ b/debug.cpp
@@ -833,23 +833,11 @@ int read_cheat_args() {
     cheat();
     quantum = true;
     }
-  else if(argis("-chaos-circle")) {
+  else if(argis("-lands")) {
     PHASEFROM(2);
     cheat();
     stop_game();
-    chaosmode = 2;
-    }
-  else if(argis("-chaos-total")) {
-    PHASEFROM(2);
-    cheat();
-    stop_game();
-    chaosmode = 3;
-    }
-  else if(argis("-chaos-random")) {
-    PHASEFROM(2);
-    cheat();
-    stop_game();
-    chaosmode = 4;
+    shift(); land_structure = (eLandStructure) (argi());
     }
   else if(argis("-fix")) {
     PHASE(1);
diff --git a/environment.cpp b/environment.cpp
index 54dc22dc..0caf3555 100644
--- a/environment.cpp
+++ b/environment.cpp
@@ -336,7 +336,7 @@ EX void bfs() {
         // remove treasures
         if(!peace::on && c2->item && c2->cpdist == distlimit && itemclass(c2->item) == IC_TREASURE &&
           c2->item != itBabyTortoise &&
-          (items[c2->item] >= (chaosmode?10:20) + currentLocalTreasure || getGhostcount() >= 2)) {
+          (items[c2->item] >= (ls::any_chaos()?10:20) + currentLocalTreasure || getGhostcount() >= 2)) {
             c2->item = itNone;
             if(c2->land == laMinefield) { c2->landparam &= ~3; }
             }
diff --git a/geom-exp.cpp b/geom-exp.cpp
index f1988b67..038ac4cb 100644
--- a/geom-exp.cpp
+++ b/geom-exp.cpp
@@ -151,7 +151,7 @@ EX bool showquotients;
 
 string validclasses[4] = {" (X)", " (½)", "", " (!)"};
   
-void ge_land_selection() {
+EX void ge_land_selection() {
   cmode = sm::SIDE | sm::MAYDARK;
   gamescreen(0);  
 
@@ -210,16 +210,6 @@ void ge_land_selection() {
         }));
       });
     }
-  dialog::addBreak(50);
-  if(chaosUnlocked && !quotient && !euclid && !sphere && !walls_not_implemented()) {
-    dialog::addItem(XLAT("Chaos mode"), '1');
-    dialog::add_action(dual::mayboth([] {
-      if(chaosUnlocked) dialog::do_if_confirmed([] {
-        stop_game_and_switch_mode(rg::chaos);
-        start_game();
-        });
-      }));
-    }
   dialog::addItem(XLAT("next page"), '-');
 
   dialog::addBreak(25);
@@ -1006,8 +996,7 @@ EX void showEuclideanMenu() {
     }
   
   dialog::addBreak(100);
-  dialog::addSelItem(XLAT("land"), XLAT1(linf[specialland].name), 'l');
-  dialog::add_action_push(ge_land_selection);
+  menuitem_land_structure('l');
   
   if(specialland == laMinefield && bounded) {
     dialog::addSelItem(XLAT("number of mines"), its(bounded_mine_quantity), 'm');
diff --git a/graph.cpp b/graph.cpp
index eedd0e9b..53b20946 100644
--- a/graph.cpp
+++ b/graph.cpp
@@ -3337,7 +3337,7 @@ EX void floorShadow(cell *c, const shiftmatrix& V, color_t col) {
 EX bool use_warp_graphics() {
   if(shmup::on) return false;
   if(geosupport_football() != 2) return false;
-  if(chaosmode == 3 || chaosmode == 4) return false;
+  if(ls::chaoticity() >= 75) return false;
   return true;
   }
 
diff --git a/help.cpp b/help.cpp
index ef9326f9..b8859cc5 100644
--- a/help.cpp
+++ b/help.cpp
@@ -836,7 +836,7 @@ EX void describeMouseover() {
       out += XLAT(" (level %1)", its(snakelevel(c)));
     if(c->land == laDryForest && c->landparam) 
       out += " (" + its(c->landparam)+"/10)";
-    if(c->land == laOcean && chaosmode)
+    if(c->land == laOcean && ls::any_chaos())
       out += " (" + its(c->CHAOSPARAM)+"S"+its(c->SEADIST)+"L"+its(c->LANDDIST)+")";
     else if(c->land == laOcean && c->landparam <= 25) {
       if(shmup::on)
diff --git a/hyper.h b/hyper.h
index eb623a81..3bada3aa 100644
--- a/hyper.h
+++ b/hyper.h
@@ -429,7 +429,7 @@ extern videopar vid;
 
 #define BUGCOLORS 3
 
-#define big_unlock (inv::on && !chaosmode)
+#define big_unlock (inv::on && !ls::any_chaos())
 
 // land completion for shared unlocking
 #define U5 (big_unlock ? 10 : 5)
diff --git a/inventory.cpp b/inventory.cpp
index cdf9ba9d..b54406e7 100644
--- a/inventory.cpp
+++ b/inventory.cpp
@@ -146,7 +146,7 @@ EX namespace inv {
       }
     else {
       bool nextfound = false;
-      int fst = (chaosmode ? 5 : 10);
+      int fst = (ls::any_chaos() ? 5 : 10);
       if(qty >= fst) remaining[o]++;
       else {
         if(whichorbinfo == o) {
@@ -162,7 +162,7 @@ EX namespace inv {
         }
       int last = fst;
       for(int k=0; k<30 || !nextfound; k++) {
-        int maxstep = chaosmode ? 10 + 2 * k : 15 + 5 * k;
+        int maxstep = ls::any_chaos() ? 10 + 2 * k : 15 + 5 * k;
         if(o == itOrbMirror)
           maxstep += 5 * (k-1) * (k-2);
         else
@@ -243,7 +243,7 @@ EX namespace inv {
     for(auto& oi: orbinfos) {
       if(oi.flags & orbgenflags::OSM_AT10) {
         eItem it = treasureType(oi.l);
-        int fst = chaosmode ? 5 : 10;
+        int fst = ls::any_chaos() ? 5 : 10;
         if(items[it] >= fst) {
           remaining[oi.orb]++;
           }
diff --git a/items.cpp b/items.cpp
index bc61529a..f6a465b3 100644
--- a/items.cpp
+++ b/items.cpp
@@ -476,7 +476,7 @@ EX void gainItem(eItem it) {
   if(it == itHyperstone && items[itHyperstone] == 10)
     achievement_victory(true);
 
-  if(chaosmode && gold() >= 300)
+  if(ls::any_chaos() && gold() >= 300)
     achievement_gain_once("CHAOS", rg::chaos);
 
 #if ISMOBILE
@@ -533,7 +533,7 @@ EX void placeItems(int qty, eItem it) {
   }
 
 EX bool cantGetGrimoire(cell *c2, bool verbose IS(true)) {
-  if(chaosmode) return false;
+  if(ls::any_chaos()) return false;
   if(!eubinary && !c2->master->alt) return false;
   if(c2->item == itGrimoire && items[itGrimoire] > celldistAlt(c2)/-temple_layer_size()) {
     if(verbose)
@@ -624,13 +624,13 @@ EX void collectMessage(cell *c2, eItem which) {
   else if(which == itPalace && items[itPalace] == U5-1 && !specialmode && isLandIngame(laDungeon)) {
     addMessage(XLAT("The rug depicts a man in a deep dungeon, unable to leave."));
     }
-  else if(which == itFeather && items[itFeather] == 25-1 && !specialmode && inv::on && !chaosmode)
+  else if(which == itFeather && items[itFeather] == 25-1 && !specialmode && inv::on && !ls::any_chaos())
     addMessage(XLAT("You feel the presence of free saves on the Crossroads."));
-  else if(which == itHell && items[itHell] == 25-1 && !specialmode && inv::on && !chaosmode)
+  else if(which == itHell && items[itHell] == 25-1 && !specialmode && inv::on && !ls::any_chaos())
     addMessage(XLAT("You feel the Orbs of Yendor nearby..."));
-  else if(which == itHell && items[itHell] == 50-1 && !specialmode && inv::on && !chaosmode)
+  else if(which == itHell && items[itHell] == 50-1 && !specialmode && inv::on && !ls::any_chaos())
     addMessage(XLAT("You feel the Orbs of Yendor in the Crossroads..."));
-  else if(which == itHell && items[itHell] == 100-1 && !specialmode && inv::on && !chaosmode)
+  else if(which == itHell && items[itHell] == 100-1 && !specialmode && inv::on && !ls::any_chaos())
     addMessage(XLAT("You feel the Orbs of Yendor everywhere..."));
   else if(which == itBone && items[itBone] % 25 == 24 && !specialmode && inv::on)
     addMessage(XLAT("You have gained an offensive power!"));
diff --git a/landgen.cpp b/landgen.cpp
index 2d17c67f..0a99c509 100644
--- a/landgen.cpp
+++ b/landgen.cpp
@@ -35,7 +35,7 @@ EX void doOvergenerate() {
 
 EX bool notDippingFor(eItem i) {
   if(peace::on) return false;
-  if(chaosmode > 1) return true;
+  if(ls::chaoticity() >= 60) return true;
   int v = items[i] - currentLocalTreasure;
   if(v <= 10) return true;
   if(v >= 20) return false;
@@ -44,7 +44,7 @@ EX bool notDippingFor(eItem i) {
 
 EX bool notDippingForExtra(eItem i, eItem x) {
   if(peace::on) return false;
-  if(chaosmode > 1) return true;
+  if(ls::chaoticity() >= 60) return true;
   int v = items[i] - min(items[x], currentLocalTreasure);
   if(v <= 10) return true;
   if(v >= 20) return false;
@@ -273,7 +273,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
 
     case laPrairie: // -------------------------------------------------------------
     
-      if(d == 7 && chaosmode) {
+      if(d == 7 && ls::any_chaos()) {
         if(hrand_monster(9000) < items[itGreenGrass] - (prairie::isriver(cwt.at) ? 40 : 0) && !safety)
           c->monst = moGadfly;
         if(hrand_monster(100) < 5) c->monst = moSleepBull;
@@ -894,17 +894,17 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
     
     case laTrollheim:
       if(fargen) {
-        if(hrand(50000) < (chaosmode==1?1000:chaosmode?50:5) && c->wall != waBarrier && celldist(c) >= 7 && !safety && !peace::on) {
+        if(hrand(50000) < (ls::tame_chaos() ? 1000: ls::any_chaos() ?50:5) && c->wall != waBarrier && celldist(c) >= 7 && !safety && !peace::on) {
           bool okay = true;
           forCellCM(c2, c) forCellCM(c3, c2) forCellCM(c4, c3) forCellCM(c5, c4) {
-            cell *cx = chaosmode ? c3 : c5;
+            cell *cx = ls::any_chaos() ? c3 : c5;
             if(cx->land != laTrollheim && cx->land != laNone)
               okay = false;
             if(cx->bardir != NODIR) okay = false;
             }
           if(okay) {
             forCellCM(c2, c) forCellCM(c3, c2) forCellCM(c4, c3) forCellCM(c5, c4) {
-              cell *cx = chaosmode ? c3 : c5;
+              cell *cx = ls::any_chaos() ? c3 : c5;
               cx->bardir = NOBARRIERS;
               setland(cx, laTrollheim);
               }
@@ -1575,10 +1575,10 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
       ONEMPTY {
         // depth!
         int d = 
-          chaosmode ? -15 * items[itGrimoire]:
+          ls::any_chaos() ? -15 * items[itGrimoire]:
           (eubinary || c->master->alt) ? celldistAlt(c) : 10;
         // remember: d is negative
-        if(chaosmode ? hrand(100) < 25 : d % temple_layer_size() == 0) {
+        if(ls::any_chaos() ? hrand(100) < 25 : d % temple_layer_size() == 0) {
           if(hrand_monster(5000) < 20 - 2*d && !c->monst && !peace::on)
             c->monst = moTentacle, c->mondir = NODIR;
           }
@@ -1593,7 +1593,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
             c->monst = moCultistLeader;
           else if(hrand(5000) < 250 && !peace::on)
             c->item = itGrimoire;
-          else if(hrand(5000) < 10 && (chaosmode ? items[itGrimoire] >= treasureForLocal() : -d > temple_layer_size() * 10) && !peace::on && !inv::on)
+          else if(hrand(5000) < 10 && (ls::any_chaos() ? items[itGrimoire] >= treasureForLocal() : -d > temple_layer_size() * 10) && !peace::on && !inv::on)
             c->item = itOrbDragon;
           }
         }
@@ -1615,9 +1615,9 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
       ONEMPTY {
         if(hrand(6000) < PT(120 + (kills[moLesser]), 240) && notDippingFor(itHell))
           c->item = itHell;
-        if(hrand_monster(8000) < 40 + items[itHell] * (chaosmode?4:1) + yendor::hardness())
+        if(hrand_monster(8000) < 40 + items[itHell] * (ls::any_chaos()?4:1) + yendor::hardness())
           c->monst = moLesser;
-        else if(hrand_monster(24000) < 40 + items[itHell] * (chaosmode?4:1) + yendor::hardness())
+        else if(hrand_monster(24000) < 40 + items[itHell] * (ls::any_chaos()?4:1) + yendor::hardness())
           c->monst = moGreater;
         }
       break;
@@ -1653,7 +1653,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
     
     case laHive:
       if(fargen) {
-        if(hrand(2000) < (chaosmode==1 ? 1000 : (PURE && !chaosmode) ?200: chaosmode ? 10 : 2) && !safety) 
+        if(hrand(2000) < (ls::tame_chaos() ? 1000 : (PURE && !ls::any_chaos()) ?200: ls::any_chaos() ? 10 : 2) && !safety) 
           hive::createBugArmy(c);
         if(hrand(2000) < 100 && !c->wall && !c->item && !c->monst) {
           int nww = 0;
@@ -1918,7 +1918,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
           if(hrand(1000) < 150 && celldist(c) >= 3 && !pseudohept(c)) 
             c->wall = waSmallTree;
           int q = 0;
-          if(BITRUNCATED && !chaosmode && !weirdhyperbolic) for(int i=0; i<c->type; i++) 
+          if(BITRUNCATED && !ls::any_chaos() && !weirdhyperbolic) for(int i=0; i<c->type; i++) 
             if(c->move(i) && !isWarpedType(c->move(i)->land) && c->move(i)->land != laCrossroads4) 
               q++;
           if(q == 1) c->wall = waWarpGate;
@@ -1927,7 +1927,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
         if(c->land == laWarpSea) {
           c->wall = waSea;
           int q = 0;
-          if(BITRUNCATED && !chaosmode) for(int i=0; i<c->type; i++) 
+          if(BITRUNCATED && !ls::any_chaos()) for(int i=0; i<c->type; i++) 
             if(c->move(i) && !isWarpedType(c->move(i)->land)) q++;
           if(q == 1) c->wall = waWarpGate;
           }      
@@ -1994,7 +1994,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
         for(int i=0; i<c->type; i++) {
           cell *c2 = c->move(i);          
           if(c2 && c2->wall == waRose) nww++;
-          if(c2 && !chaosmode) for(int j=0; j<c2->type; j++) {
+          if(c2 && !ls::any_chaos()) for(int j=0; j<c2->type; j++) {
             cell *c3 = c2->move(j);
             // note: c3->land is required for Android --
             // not strictly equivalent since another land there might be not yet generated
@@ -2009,7 +2009,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
         }
       ONEMPTY {
         if(hrand(2000) < PT(25 + min(kills[moFalsePrincess] + kills[moRoseBeauty] + kills[moRoseLady], 200), 100) && notDippingFor(itRose)) {
-          if(chaosmode == 3)
+          if(land_structure == lsTotalChaos)
             c->item = itRose;
           else for(int t=0; t<c->type; t++) if(c->move(t) && c->move(t)->wall == waRose)
             c->item = itRose;
@@ -2118,7 +2118,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
   
         if(placecolumn)
           c->wall = waColumn;
-        else if((c->landparam >= 1 && c->landparam <= 25) || chaosmode) {
+        else if((c->landparam >= 1 && c->landparam <= 25) || ls::any_chaos()) {
           if(hrand(1000) < 5)
             c->wall = waBoat;
           if(hrand(1000) < PT(50 + kills[moAlbatross]/2, 150) && !peace::on)
@@ -2292,8 +2292,8 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
            chasmify(c);
            c->wall = shmup::on ? waNone : waChasm;
            }
-         int cmf[5] = {0, 1, 3, 5, 10};
-         if(inv::on && chaosmode && items[itFeather] && hrand(1000) < cmf[chaosmode] && !c->item && !c->monst)
+         int cmf[10] = {0, 1, 3, 5, 10, 0, 0, 0, 0, 0};
+         if(inv::on && ls::any_chaos() && items[itFeather] && hrand(1000) < cmf[land_structure] && !c->item && !c->monst)
            c->item = itOrbSafety;
          }
        break;
@@ -2648,7 +2648,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
           c->wall = wetwalls[a];
           }
         bool border = false;
-        if(!chaosmode) forCellEx(c1, c) if(c1->land != laWet) border = true;
+        if(ls::any_order()) forCellEx(c1, c) if(c1->land != laWet) border = true;
         if(border) {
           if(pseudohept(c)) c->wall = waDeepWater;
           else c->wall = waShallow;
@@ -2756,8 +2756,29 @@ EX void setland_randomwalk(cell *c) {
   }
 
 EX void set_land_for_geometry(cell *c) {
-  if(0);
-  else if(chaosmode > 1) ;
+
+  if(!c->land && isize(currentlands)) {
+    if(land_structure == lsTotalChaos) {
+      setland(c, currentlands[hrand(isize(currentlands))]);
+      return;
+      }
+    if(ls::patched_chaos() && stdeuc) { /* note: Nil pached chaos done in setLandNil */
+      cell *c2 = c;
+      while(true) {
+        forCellCM(c3, c2) if(cdist50(c3) < cdist50(c2)) { c2 = c3; goto again; }
+        break;
+        again: ;
+        }
+      if(!c2->land) setland(c2, currentlands[hrand(isize(currentlands))]);
+      c->land = c2->land;
+      return;
+      }
+    if(land_structure == lsChaosRW) {
+      setland_randomwalk(c);
+      return;
+      }
+    }
+  else if(ls::chaoticity() >= 60) ;
   #if CAP_CRYSTAL
   else if(cryst) crystal::set_land(c);
   #endif
@@ -2828,35 +2849,19 @@ EX void setdist(cell *c, int d, cell *from) {
       }
     #endif
   
-    if(!c->land && from && (WDIM == 3 || !among(from->land, laBarrier, laElementalWall, laHauntedWall, laOceanWall)) && !quotient && !(chaosmode > 1)) {
+    if(!c->land && from && (WDIM == 3 || !among(from->land, laBarrier, laElementalWall, laHauntedWall, laOceanWall)) && !quotient && ls::chaoticity() < 60) {
       if(!hasbardir(c)) setland(c, from->land);
       }
-    if(c->land == laTemple && !tactic::on && !chaosmode) setland(c, laRlyeh);
-    if(c->land == laMountain && !tactic::on && !chaosmode) setland(c, laJungle);
-    if(c->land == laClearing && !tactic::on) setland(c, laOvergrown);
-    if(c->land == laWhirlpool && !tactic::on && !yendor::on) setland(c, laOcean);
-    if(c->land == laCamelot && !tactic::on) setland(c, laCrossroads);
-    if(c->land == laBrownian && !chaosmode) setland(c, laOcean);
-    
-    if(chaosmode && !c->land && isize(currentlands)) {
-      if(chaosmode == 3) setland(c, currentlands[hrand(isize(currentlands))]);
-      if(chaosmode == 2) {
-        if(stdeuc) {
-          cell *c2 = c;
-          while(true) {
-            forCellCM(c3, c2) if(cdist50(c3) < cdist50(c2)) { c2 = c3; goto again; }
-            break;
-            again: ;
-            }
-          if(!c2->land) setland(c2, currentlands[hrand(isize(currentlands))]);
-          c->land = c2->land;
-          }
-        else chaosmode = 4;
-        }
-      if(chaosmode == 4)
-        setland_randomwalk(c);
-      }
+    if(c->land == laTemple && ls::any_order()) setland(c, laRlyeh);
 
+    if(!ls::single()) {
+      if(c->land == laMountain) setland(c, laJungle);
+      if(c->land == laClearing) setland(c, laOvergrown);
+      if(c->land == laWhirlpool) setland(c, laOcean);
+      if(c->land == laCamelot) setland(c, laCrossroads);
+      if(c->land == laBrownian) setland(c, laOcean);
+      }
+    
 #if CAP_DAILY
     if(!daily::on) {
 #else
@@ -2864,8 +2869,6 @@ EX void setdist(cell *c, int d, cell *from) {
 #endif
       set_land_for_geometry(c);
       }
-    
-    // if(chaosmode) setland(c, getCLand(c));
     }
   
   if(d == BARLEV && c->land == laCanvas)  {
@@ -2876,11 +2879,11 @@ EX void setdist(cell *c, int d, cell *from) {
     }
 
   #if CAP_FIELD
-  if(d >= BARLEV-1 && c->land == laPrairie && !chaosmode)
+  if(d >= BARLEV-1 && c->land == laPrairie && !ls::any_chaos())
     prairie::spread(c, from);
   #endif
 
-  if(d < BARLEV && c->land == laPrairie && !c->landparam && !chaosmode) {
+  if(d < BARLEV && c->land == laPrairie && !c->landparam && !ls::any_chaos()) {
     printf("d=%d/%d\n", d, BARLEV);
     raiseBuggyGeneration(c, "No landparam set");
     return;
diff --git a/landlock.cpp b/landlock.cpp
index 7e7c1643..83817a89 100644
--- a/landlock.cpp
+++ b/landlock.cpp
@@ -9,15 +9,8 @@
 namespace hr {
 
 EX bool in_full_game() {
-  if(tactic::on) return false;
-  if(princess::challenge) return false;
-  if(chaosmode) return true;
-  if(euclid && isCrossroads(specialland)) return true;
-  if(weirdhyperbolic && specialland == laCrossroads4) return true;
-  if(cryst && isCrossroads(specialland)) return true;
-  if((in_s2xe() || nonisotropic || (hybri && hybrid::under_class() != gcSphere)) && isCrossroads(specialland)) return true;
-  if(geometry == gNormal && !NONSTDVAR) return true;
-  return false;
+  if(ls::single()) return false;
+  return true;
   }
 
 EX bool nodisplay(eMonster m) {
@@ -87,7 +80,84 @@ EX eLand oppositeElement(eLand l, eLand l2) {
 EX eLand firstland = laIce;
 EX eLand specialland = laIce;
 
-EX int chaosmode = 0;
+#if HDR
+enum eLandStructure { lsNiceWalls, lsChaos, lsPatchedChaos, lsTotalChaos, lsChaosRW, lsWallChaos, lsSingle, lsNoWalls, lsGUARD };
+#endif
+
+EX eLandStructure land_structure;
+
+EX namespace ls {
+
+EX bool single() { return land_structure == lsSingle; }
+
+EX bool any_chaos() { return among(land_structure, lsChaos, lsPatchedChaos, lsWallChaos, lsTotalChaos, lsChaosRW); }
+EX bool std_chaos() { return land_structure == lsChaos; }
+EX bool wall_chaos() { return land_structure == lsWallChaos; }
+EX bool patched_chaos() { return land_structure == lsPatchedChaos; }
+
+EX bool any_order() { return among(land_structure, lsNiceWalls, lsNoWalls); }
+EX bool nice_walls() { return land_structure == lsNiceWalls; }
+EX bool no_walls() { return land_structure == lsNoWalls; }
+
+EX bool any_nowall() { return no_walls() || std_chaos(); }
+EX bool any_wall() { return nice_walls() || wall_chaos(); }
+
+EX int chaoticity() {
+  if(land_structure == lsTotalChaos) return 100;
+  if(land_structure == lsChaosRW) return 80;
+  if(land_structure == lsPatchedChaos) return 60;
+  if(land_structure == lsChaos) return 40;
+  if(land_structure == lsWallChaos) return 30;
+  if(land_structure == lsSingle) return 0;
+  return 10;  
+  }
+
+EX bool tame_chaos() { return any_chaos() && chaoticity() < 35; }
+EX }
+
+EX string land_structure_name(bool which) {
+  switch(land_structure) {
+    case lsNiceWalls:
+      return XLAT("standard");
+    case lsChaos:
+      return XLAT("Chaos mode");
+    case lsPatchedChaos:
+      return XLAT("patched Chaos");
+    case lsWallChaos:
+      return XLAT("excessive walls");
+    case lsTotalChaos:
+      return XLAT("total chaos");
+    case lsChaosRW:
+      return XLAT("random-walk chaos");
+    case lsSingle:
+      return which ? XLAT("single land: ") + XLATN(linf[specialland].name) : XLAT("single land");
+    case lsNoWalls:
+      return XLAT("wall-less");
+    default:
+      return "error structure";
+    }
+  }
+
+EX void fix_land_structure_choice() {  
+  if(bounded) {
+    if(land_structure != lsTotalChaos && land_structure != lsChaosRW)
+      land_structure = lsSingle;
+    }
+  if(tactic::on || princess::challenge)
+    land_structure = lsSingle;
+  if(yendor::on)
+    land_structure = yendor::get_land_structure();
+  if(!nice_walls_available() && land_structure == lsNiceWalls)
+    land_structure = lsNoWalls;
+  if(!nice_walls_available() && land_structure == lsWallChaos)
+    land_structure = lsChaos;
+  if(walls_not_implemented() && among(land_structure, lsChaos, lsNoWalls))
+    land_structure = lsSingle;
+  if(land_structure == lsPatchedChaos && !(stdeuc || nil || cryst || (euclid && WDIM == 3)))
+    land_structure = lsSingle;
+  if(bounded && !among(land_structure, lsChaosRW, lsTotalChaos, lsSingle))
+    land_structure = lsSingle;
+  }
 
 EX bool landUnlockedRPM(eLand n) {
   if(isRandland(n) == 2) return true;
@@ -107,6 +177,8 @@ EX bool landUnlocked(eLand l) {
   
   back:
   
+  if(princess::challenge) return among(l, laPalace, laPrincessQuest);
+  
   switch(l) {
     #define LAND(a,b,c,d,e,f,g) case c:
     #define REQ(x) x return true;
@@ -219,13 +291,13 @@ EX bool incompatible(eLand nw, eLand old) {
   }
 
 EX bool rlyehComplete() {
-  if(chaosmode) return items[itStatue] >= 1;
+  if(ls::any_chaos()) return items[itStatue] >= 1;
   return items[itStatue] >= 10 || items[itGrimoire] >= 10;
   }
 
 bool lchance(eLand l) { 
   if(tactic::on || yendor::on || racing::on || ((geometry || GOLDBERG) && specialland == laElementalWall)) return true;
-  if(chaosmode) return hrand(100) < 25;
+  if(ls::any_chaos()) return hrand(100) < 25;
   return hrand(100) >= 40 * kills[elementalOf(l)] / (elementalKills()+1); 
   }
 
@@ -274,16 +346,13 @@ EX bool createOnSea(eLand old) {
     old == laWarpSea || old == laCaribbean || old == laKraken ||
     (old == laLivefjord && hrand(2)) || 
     (old == laDocks && hrand(2)) ||
-    (old == laOcean && (chaosmode ? hrand(2) : !generatingEquidistant));
+    (old == laOcean && (ls::any_chaos() ? hrand(2) : !generatingEquidistant));
   }
 
 EX hookset<eLand(eLand)> hooks_nextland;
 
 EX eLand getNewLand(eLand old) {
 
-  if(old == laMirror && !chaosmode && hrand(10) >= ((tactic::on || racing::on) ? 0 : markOrb(itOrbLuck) ? 5 : 2)) return laMirrored;
-  if(old == laTerracotta && !chaosmode && hrand(5) >= ((tactic::on || racing::on) ? 0 : markOrb(itOrbLuck) ? 2 : 1) && !weirdhyperbolic) return laTerracotta;
-    
   eLand l = callhandlers(laNone, hooks_nextland, old);
   if(l) return l;
   
@@ -291,7 +360,7 @@ EX eLand getNewLand(eLand old) {
   
   if(old == laTortoise) return laDragon;
 
-  if(yendor::on && chaosmode) {
+  if(yendor::on && ls::any_chaos()) {
     while(true) {
       eLand n = eLand(hrand(landtypes));
       if(n == old) continue;
@@ -333,8 +402,7 @@ EX eLand getNewLand(eLand old) {
   #endif
 
   if(tactic::on) return specialland;
-  if((weirdhyperbolic || cheater) && specialland != old && specialland != laCrossroads4 && specialland != laIce && !chaosmode && old != laBarrier && !isCyclic(specialland) && specialland != laBrownian)
-    return specialland;
+  if(specialland != old && easy_to_find_specialland) return specialland;
 
   if(yendor::on && (yendor::clev().flags & YF_WALLS)) {
     if(old != yendor::clev().l) return yendor::clev().l;
@@ -351,7 +419,7 @@ EX eLand getNewLand(eLand old) {
   if(old == laDragon && tortoise::seek() && hrand(100) < 50)
     return laTortoise;
   
-  if(isWarpedType(old) && (hrand(100) < 25) && chaosmode) return eLand(old ^ laWarpCoast ^ laWarpSea);
+  if(isWarpedType(old) && (hrand(100) < 25) && ls::std_chaos()) return eLand(old ^ laWarpCoast ^ laWarpSea);
 
   if(createOnSea(old)) 
       return getNewSealand(old);
@@ -429,9 +497,9 @@ EX eLand getNewLand(eLand old) {
     tab[cnt++] = laCrossroads;
     if(!generatingEquidistant) tab[cnt++] = laCrossroads2;
     if(rlyehComplete()) tab[cnt++] = laRlyeh;
-    else if(chaosmode && (old == laWarpCoast || old == laLivefjord || old == laOcean)) 
+    else if(ls::std_chaos() && (old == laWarpCoast || old == laLivefjord || old == laOcean)) 
       tab[cnt++] = laRlyeh;
-    if(items[itStatue] >= U5 && chaosmode)
+    if(items[itStatue] >= U5 && ls::std_chaos())
       tab[cnt++] = laTemple;
     if(old == laCrossroads || old == laCrossroads2) tab[cnt++] = laOcean;
     if(old == laOcean) tab[cnt++] = laCrossroads;
@@ -440,11 +508,11 @@ EX eLand getNewLand(eLand old) {
     }
 
   if(gold() >= R90) {
-    if(!chaosmode) tab[cnt++] = laPrairie;
+    if(!ls::std_chaos()) tab[cnt++] = laPrairie;
     if(old == laPrairie) LIKELY tab[cnt++] = laBull;
-    if(old == laBull && !chaosmode) LIKELY tab[cnt++] = laPrairie;
-    if(chaosmode && geometry) tab[cnt++] = laDual;
-    if(chaosmode && geosupport_threecolor()) tab[cnt++] = laSnakeNest;
+    if(old == laBull && !ls::any_chaos()) LIKELY tab[cnt++] = laPrairie;
+    if(ls::std_chaos() && geometry) tab[cnt++] = laDual;
+    if(ls::std_chaos() && geosupport_threecolor()) tab[cnt++] = laSnakeNest;
     }
   
   if(landUnlocked(laTrollheim)) {
@@ -799,7 +867,7 @@ EX land_validity_t& land_validity(eLand l) {
   if(l == laDual && (!has_nice_dual() || nonisotropic))
     return dont_work;
   
-  if(l == laHaunted && chaosmode)
+  if(l == laHaunted && ls::std_chaos())
     return not_in_chaos;
   
   // standard, non-PTM specific
@@ -807,11 +875,11 @@ EX land_validity_t& land_validity(eLand l) {
     return not_in_ptm;
     
   // standard non-PTM non-chaos specific
-  if((l == laCrossroads5 || l == laCrossroads2) && (geometry || chaosmode))
+  if((l == laCrossroads5 || l == laCrossroads2) && (geometry || ls::any_chaos()))
     return some0;
     
   // special construction in the Chaos mode
-  if(chaosmode && (l == laTemple || l == laHive || l == laOcean || l == laHaunted))
+  if(ls::any_chaos() && (l == laTemple || l == laHive || l == laOcean || l == laHaunted))
     return special_chaos;
   
   if(l == laWhirlpool && a4)
@@ -842,7 +910,7 @@ EX land_validity_t& land_validity(eLand l) {
   // equidistant-based lands
   if(isEquidLand(l)) {
     // no equidistants supported in chaos mode
-    if(chaosmode) 
+    if(ls::any_chaos()) 
       return not_in_chaos;
     // the algorithm fails in Archimedean DUAL
     if(arcm::in() && DUAL)
@@ -864,7 +932,7 @@ EX land_validity_t& land_validity(eLand l) {
       return ok;
     }
   
-  if(l == laPrincessQuest && chaosmode)
+  if(l == laPrincessQuest && ls::any_chaos())
     return not_in_chaos;
    
   if(l == laPrincessQuest && tactic::on)
@@ -879,14 +947,14 @@ EX land_validity_t& land_validity(eLand l) {
   if(l == laPrincessQuest && multi::players > 1)
     return not_in_multi;
 
-  if(l == laMountain && chaosmode)
+  if(l == laMountain && ls::any_chaos())
     return not_in_chaos;
   
-  if(l == laBrownian && chaosmode)
+  if(l == laBrownian && ls::any_chaos())
     return not_in_chaos;
   
   // works correctly only in some geometries
-  if(l == laClearing && chaosmode)
+  if(l == laClearing && ls::any_chaos())
     return not_in_chaos;
   
   if(l == laClearing)
@@ -904,7 +972,7 @@ EX land_validity_t& land_validity(eLand l) {
   
   // horocycle-based lands, not available in bounded geometries nor in Chaos mode
   if(l == laWhirlpool || l == laCamelot || l == laCaribbean || l == laTemple || l == laHive) {
-    if(chaosmode) {
+    if(ls::any_chaos()) {
       if(l == laTemple || l == laHive) 
         return special_chaos;
       return not_in_chaos;
@@ -914,7 +982,7 @@ EX land_validity_t& land_validity(eLand l) {
     if(INVERSE) return not_implemented;
     }
   
-  if(chaosmode && isCrossroads(l))
+  if(ls::any_chaos() && isCrossroads(l))
     return not_in_chaos;
   
   // this pattern does not work on elliptic and small spheres
diff --git a/legacy.cpp b/legacy.cpp
index c65624ff..0d8ac0e6 100644
--- a/legacy.cpp
+++ b/legacy.cpp
@@ -72,7 +72,7 @@ void loadOldConfig(FILE *f) {
 
   shmup::loadConfig(f);
 
-  aa = rug::renderonce; bb = rug::rendernogl; dd = chaosmode; 
+  aa = rug::renderonce; bb = rug::rendernogl; dd = ls::any_chaos();
   int ee = vid.steamscore;
   #if CAP_RUG
   double rs = 2/rug::model_distance;
@@ -81,7 +81,7 @@ void loadOldConfig(FILE *f) {
   #endif
   err=fscanf(f, "%d%d%d%d%lf%d%d", &aa, &bb, &rug::texturesize, &cc, &rs, &ee, &dd);
   rug::renderonce = aa; rug::rendernogl = bb; 
-  chaosmode = dd; vid.steamscore = ee;
+  land_structure = (eLandStructure) dd; vid.steamscore = ee;
   #if CAP_RUG
   rug::model_distance = 2/rs;
   #endif
@@ -204,7 +204,7 @@ int modecodetable[42][6] = {
 
 EX modecode_t legacy_modecode() {
   if(int(geometry) > 3 || int(variation) > 1) return UNKNOWN;
-  if(chaosmode > 1) return UNKNOWN;
+  if(!ls::nice_walls() && !ls::std_chaos()) return UNKNOWN;
   // compute the old code
   int xcode = 0;
 
@@ -219,7 +219,7 @@ EX modecode_t legacy_modecode() {
     if(elliptic) xcode += 6;
     }
   
-  if(chaosmode) xcode += 21;
+  if(ls::any_chaos()) xcode += 21;
   
   int np = numplayers()-1; if(np<0 || np>5) np=5;
 
@@ -238,5 +238,40 @@ EX modecode_t legacy_modecode() {
   return mct;
   }
 
+/* legacy options */
+int read_legacy_args() {
+  using namespace arg;
+  if(0);
+  else if(argis("-chaos-circle")) {
+    PHASEFROM(2);
+    stop_game();
+    land_structure = lsCircleChaos;
+    }
+  else if(argis("-chaos-total")) {
+    PHASEFROM(2);
+    stop_game();
+    land_structure = lsTotalChaos;
+    }
+  else if(argis("-chaos-random")) {
+    PHASEFROM(2);
+    stop_game();
+    land_structure = lsChaosRW;
+    }
+  else if(argis("-C") || argis("-C1")) {
+    PHASEFROM(2);
+    stop_game();
+    land_structure = lsChaos;
+    }
+  else if(argis("-C0")) {
+    PHASEFROM(2);
+    stop_game();
+    land_structure = lsNiceWalls;
+    }
+  else return 1;
+  return 0;
+  }
+
+auto ah_legacy = addHook(hooks_args, 0, read_legacy_args);
+
 
 }
diff --git a/mapeffects.cpp b/mapeffects.cpp
index 8bb9c503..0d66135c 100644
--- a/mapeffects.cpp
+++ b/mapeffects.cpp
@@ -637,7 +637,7 @@ EX void checkTide(cell *c) {
   if(c->land == laOcean) {
     int t = c->landparam;
     
-    if(chaosmode) {
+    if(ls::any_chaos()) {
       char& csd(c->SEADIST); if(csd == 0) csd = 7;
       char& cld(c->LANDDIST); if(cld == 0) cld = 7;
       int seadist=csd, landdist=cld;
diff --git a/menus.cpp b/menus.cpp
index e911cb5c..2859113a 100644
--- a/menus.cpp
+++ b/menus.cpp
@@ -481,7 +481,7 @@ EX void showCreative() {
 
 EX void show_chaos() {
   gamescreen(3);
-  dialog::init(XLAT("Chaos mode"));
+  dialog::init(XLAT("land structure"));
   chaosUnlocked = chaosUnlocked || autocheat;
 
   dialog::addHelp(
@@ -493,26 +493,42 @@ EX void show_chaos() {
   
   dialog::addBreak(100);
   
-  dialog::addBoolItem(XLAT("Chaos mode") + " " + ONOFF(false), !chaosmode, 'A');
-  dialog::add_action([] { dialog::do_if_confirmed([] { if(chaosUnlocked) restart_game(rg::chaos); }); });
-  
-  if(chaosUnlocked) for(int a=1; a<5; a++) {
-    if(a > 1 && ISWEB) continue;
-    if(a == 1 && walls_not_implemented()) continue;
-    dialog::addBoolItem(
-      a == 1 ? XLATN("Crossroads IV") : 
-      a == 2 ? XLATN("Palace") : 
-      a == 3 ? XLAT("total chaos") :
-      XLAT("random walk"), 
-      chaosmode == a, 'A' + a);
-    dialog::add_action([a] { dialog::do_if_confirmed([a] { 
-      int cm = chaosmode;
-      stop_game_and_switch_mode(rg::chaos); 
-      if(!chaosmode && cm != a) switch_game_mode(rg::chaos); 
-      if(chaosmode) chaosmode = a; 
-      start_game(); 
-      }); });
+  char key = 'a';
+  for(int i=0; i<lsGUARD; i++) {
+    dynamicval<eLandStructure> dls(land_structure);
+    auto li = eLandStructure(i);
+    land_structure = li;
+    fix_land_structure_choice();
+    if(ls::any_chaos() && !chaosUnlocked) continue;
+    if(li == lsNoWalls && geometry == gNormal && !chaosUnlocked) continue;
+    if(land_structure == i) {
+      dialog::addBoolItem(land_structure_name(false), land_structure == dls.backup, key + i);
+      dialog::add_action(dual::mayboth([li] {
+        dialog::do_if_confirmed([li] {
+          stop_game();
+          land_structure = li;
+          start_game();
+          });
+        }));
+      }
     }
+  
+  dialog::addBreak(100);
+  dialog::addSelItem(XLAT("land"), XLAT1(linf[specialland].name), 'l');
+  dialog::add_action_push(ge_land_selection);
+
+  dialog::addBreak(100);
+  if(ineligible_starting_land)
+    dialog::addInfo("this starting land is not eligible for achievements");
+  else if(land_structure == lsNiceWalls)
+    dialog::addInfo("eligible for most achievements");
+  else if(land_structure == lsChaos)
+    dialog::addInfo("eligible for Chaos mode achievements");
+  else if(land_structure == lsSingle)
+    dialog::addInfo("eligible for special achievements");
+  else
+    dialog::addInfo("not eligible for achievements");
+  if(cheater) dialog::addInfo("(but the cheat mode is on)");
 
   dialog::addBreak(100);
   dialog::addBack();
@@ -643,6 +659,11 @@ EX void mode_higlights() {
   dialog::addBack();
   dialog::display();
   }  
+
+EX void menuitem_land_structure(char key) {
+  dialog::addSelItem(XLAT("land structure"), land_structure_name(true), key);
+  dialog::add_action_push(show_chaos);
+  }
   
 EX void showChangeMode() {
   gamescreen(3);
@@ -677,8 +698,7 @@ EX void showChangeMode() {
     mouseovers = XLAT("One wrong move and it is game over!");
   
   multi::cpid = 0;
-  dialog::addBoolItem(XLAT("Chaos mode"), (chaosmode), 'C');
-  dialog::add_action_push(show_chaos);
+  menuitem_land_structure('l');
 
   dialog::addBoolItem(XLAT("puzzle/exploration mode"), peace::on, 'p');
   dialog::add_action_push(peace::showMenu);
diff --git a/monstergen.cpp b/monstergen.cpp
index 92e0112e..01633f63 100644
--- a/monstergen.cpp
+++ b/monstergen.cpp
@@ -377,7 +377,7 @@ EX void wandering() {
     
     if(smallbounded_generation && !c->item && hrand(5) == 0 && c->land != laHalloween) {
       if(passable(c, NULL, 0) || specialland == laKraken) {
-        if(c->land != laGraveyard && (c->land != laMotion || chaosmode || daily::on) && !haveOrbPower() && specialland != laHell) for(int it=0; it<1000 && !c->item; it++)
+        if(c->land != laGraveyard && (c->land != laMotion || !ls::single() || daily::on) && !haveOrbPower() && specialland != laHell) for(int it=0; it<1000 && !c->item; it++)
           placeLocalOrbs(c);
         if(!c->item) c->item = wanderingTreasure(c);
         if(c->item == itShard) {
diff --git a/multigame.cpp b/multigame.cpp
index 181171b0..3b023dee 100644
--- a/multigame.cpp
+++ b/multigame.cpp
@@ -58,7 +58,7 @@ void gamedata_all(gamedata& gd) {
   gd.store(cwt);
   gd.store(allmaps);
   gd.store(shmup::on);
-  gd.store(chaosmode);
+  gd.store(land_structure);
   gd.store(*current_display);
   gd.store(cgip);
   gd.store_ptr(vid);
diff --git a/orbgen.cpp b/orbgen.cpp
index 324d248b..23d9aa3f 100644
--- a/orbgen.cpp
+++ b/orbgen.cpp
@@ -490,7 +490,7 @@ EX void placePrizeOrb(cell *c) {
 
 // 10 not in chaos, less in chaos
 EX int treasureForLocal() {
-  return (chaosmode ? 1+hrand(10) : 10);
+  return (ls::any_chaos() ? 1+hrand(10) : 10);
   }
 
 EX bool extra_safety_for_memory(cell *c) {
@@ -521,7 +521,7 @@ EX void placeLocalOrbs(cell *c) {
       continue;
     if(!oi.lchance) continue;
     int ch = hrand(oi.lchance);
-    if(ch == 1 && chaosmode && hrand(2) == 0 && items[treasureType(oi.l)] * landMultiplier(oi.l) >= (11+hrand(15)))
+    if(ch == 1 && ls::any_chaos() && hrand(2) == 0 && items[treasureType(oi.l)] * landMultiplier(oi.l) >= (11+hrand(15)))
       ch = 0;
     int tc = items[treasureType(oi.l)] * landMultiplier(oi.l);
     int tcmin = treasureForLocal();
diff --git a/pattern2.cpp b/pattern2.cpp
index 9332ba4e..9f0244dd 100644
--- a/pattern2.cpp
+++ b/pattern2.cpp
@@ -174,6 +174,11 @@ int fiftyval(cell *c) {
   }
 
 EX int cdist50(cell *c) {
+  if(euclid && S3 == 4) {
+    auto co = euc2_coordinates(c);
+    int x = co.first, y = co.second;
+    return abs(szgmod(x, 5)) + abs(zgmod(y, 5));
+    }
   if(sphere || S7>7 || S6>6) return 0;
   if(euclid) {
     if(c->land == laWildWest) 
diff --git a/pcmove.cpp b/pcmove.cpp
index 199ae547..480fe08a 100644
--- a/pcmove.cpp
+++ b/pcmove.cpp
@@ -1554,7 +1554,7 @@ EX void movecost(cell* from, cell *to, int phase) {
   bool tortoiseOK = 
     to->land == from->land || to->land == laTortoise ||
     (to->land == laDragon && from->land != laTortoise) || 
-    chaosmode;
+    ls::any_chaos();
   
   if(tortoise::seek() && !from->item && !tortoiseOK && passable(from, NULL, 0) && (phase & 2)) {
     changes.ccell(from);
diff --git a/quit.cpp b/quit.cpp
index 9ef62be2..7ad2c69f 100644
--- a/quit.cpp
+++ b/quit.cpp
@@ -397,7 +397,7 @@ EX void showMission() {
     dialog::addInfo(XLAT("Kill a Vizier in the Palace to access Emerald Mine"));
   else if(items[itEmerald] < U5)
     dialog::addInfo(XLAT("Collect 5 Emeralds to access Camelot"));
-  else if(landUnlocked(laHell) && !chaosmode) {
+  else if(landUnlocked(laHell) && ls::any_order()) {
     eLand l = nextHyperstone();
     if(l) 
         dialog::addInfo(
diff --git a/scores.cpp b/scores.cpp
index d1df0d40..7defd216 100644
--- a/scores.cpp
+++ b/scores.cpp
@@ -50,7 +50,7 @@ int modediff(score *S) {
   if(variation != savevar) diff += 16;
   if(GOLDBERG && savevar == eVariation::goldberg && (S->box[342] != gp::param.first || S->box[343] != gp::param.second))
     diff += 16;
-  if(S->box[196] != chaosmode) diff += 32;
+  if(S->box[196] != (int) land_structure) diff += 32;
   if(S->box[119] != shmup::on) diff += 64;
   if(pureHardcore() && !isHardcore(S)) diff += 128;
   if(g != gNormal && S->box[120] != specialland) 
diff --git a/system.cpp b/system.cpp
index e9894f35..c81f5d2a 100644
--- a/system.cpp
+++ b/system.cpp
@@ -68,13 +68,6 @@ EX bool verless(string v, string cmp) {
   return v < cmp;
   }
 
-/** \brief should we set the starting land to specialland */
-bool do_use_special_land() {
-  return
-    !safety &&
-    (peace::on || tactic::on || geometry || NONSTDVAR || randomPatternsMode || yendor::on || racing::on);
-  }
-
 /** \brief Hooks for welcomeMessage. Return true to capture. */
 EX hookset<bool()> hooks_welcome_message;
 
@@ -135,7 +128,7 @@ EX void welcomeMessage() {
   else
     addMessage(XLAT("Welcome to HyperRogue!"));
 
-  if(do_use_special_land() || firstland != laIce) if(!daily::on) {
+  if(!safety && !daily::on) {
     auto lv = land_validity(specialland);
     if(lv.flags & lv::display_error_message)
       addMessage(XLAT(lv.msg));
@@ -154,10 +147,14 @@ EX hookset<void()> hooks_initgame;
 /** \brief These hooks are called at the end of initgame. */
 EX hookset<void()> hooks_post_initgame;
 
+EX bool ineligible_starting_land;
+
 /** \brief initialize the game */
 EX void initgame() {
   DEBBI(DF_INIT, ("initGame"));
   callhooks(hooks_initgame); 
+  
+  if(!safety) fix_land_structure_choice();
 
   if(multi::players < 1 || multi::players > MAXPLAYER)
     multi::players = 1;
@@ -175,9 +172,10 @@ EX void initgame() {
   if(racing::on) racing::apply_seed();
   #endif
   
-  bool use_special_land = do_use_special_land();
-    
-  if(use_special_land) firstland = specialland;
+  if(!safety) {
+    firstland = specialland;
+    ineligible_starting_land = !landUnlocked(specialland);
+    }
   
   if(firstland == laNone || firstland == laBarrier)
     firstland = laCrossroads;
@@ -214,10 +212,6 @@ EX void initgame() {
   pregen();  
   setdist(cwt.at, BARLEV, NULL);
 
-  if(!use_special_land && !safety) {
-    if(firstland != (princess::challenge ? laPalace : laIce)) cheater++;
-    }
-
   if((tactic::on || yendor::on || peace::on) && isCyclic(firstland)) {
     #if CAP_COMPLEX2
     camelot::anthraxBonus = items[itHolyGrail];
@@ -341,7 +335,7 @@ EX void initgame() {
     generate_mines();
     }
   
-  if(specialland == laMotion && bounded && !chaosmode && !daily::on) {
+  if(specialland == laMotion && bounded && ls::any_order() && !daily::on) {
     cwt.at->item = itOrbInvis;
     }
   
@@ -379,9 +373,6 @@ EX void initgame() {
 #if CAP_COMPLEX2
     mine::auto_teleport_charges();
 #endif
-    if(!use_special_land) {
-      if(firstland != (princess::challenge ? laPalace : laIce)) cheater++;
-      }
     welcomeMessage();
     }
   else {
@@ -424,7 +415,7 @@ EX namespace scores {
 /** \brief the amount of boxes reserved for each hr::score item */
 #define MAXBOX 500
 /** \brief currently used boxes in hr::score */
-#define POSSCORE 388
+#define POSSCORE 389
 /** \brief a struct to keep local score from an earlier game */
 struct score {
   /** \brief version used */
@@ -739,7 +730,9 @@ EX void applyBoxes() {
   applyBoxM(moFalsePrincess);
   applyBoxM(moRoseLady);
   applyBoxM(moRoseBeauty);
-  applyBoxNum(chaosmode, "Chaos mode");
+  int ls = (int) land_structure;
+  applyBoxNum(ls, "land structure");
+  land_structure = (eLandStructure) ls;
   applyBoxNum(multi::players, "shmup players");
   if(multi::players < 1 || multi::players > MAXPLAYER)
     multi::players = 1;
@@ -895,6 +888,7 @@ EX void applyBoxes() {
   list_invorb();
 
   applyBoxNum(saved_modecode, "modecode");
+  applyBoxBool(ineligible_starting_land, "ineligible_starting_land");
 
   if(POSSCORE != boxid) printf("ERROR: %d boxes\n", boxid);
   if(isize(invorb)) { println(hlog, "ERROR: Orbs not taken into account"); exit(1); }
@@ -919,7 +913,7 @@ modecode_t fill_modecode() {
   if(among(geometry, gArchimedean, gProduct, gRotSpace, gArbitrary))
     return 6; /* these would not be saved nor loaded correctly */
   dynamicval<bool> sp3(shmup::on, save.box[119]);
-  dynamicval<int> sp4(chaosmode, save.box[196]);
+  dynamicval<eLandStructure> sp4(land_structure, (eLandStructure) save.box[196]);
   dynamicval<eVariation> sp5(variation, (eVariation) save.box[186]);
   dynamicval<int> sp7(gp::param.first, save.box[342]);
   dynamicval<int> sp8(gp::param.second, save.box[343]);
@@ -1077,7 +1071,10 @@ EX void saveStats(bool emergency IS(false)) {
   fprintf(f, "cells generated: %d\n", cellcount);
   if(pureHardcore()) fprintf(f, "Pure hardcore mode\n");
   if(geometry) fprintf(f, "Geometry: %s/%s/%s\n", gp::operation_name().c_str(), ginf[geometry].tiling_name.c_str(), ginf[geometry].quotient_name.c_str());
-  if(chaosmode) fprintf(f, "Chaos mode\n");
+
+  if(!ls::nice_walls())
+    fprintf(f, "land structure: %s\n", land_structure_name(true).c_str());
+  
   if(shmup::on) fprintf(f, "Shoot-em up mode\n");
   if(inv::on) fprintf(f, "Inventory mode\n");
   if(multi::players > 1) fprintf(f, "Multi-player (%d players)\n", multi::players);
@@ -1309,10 +1306,7 @@ EX void set_geometry(eGeometry target) {
       hybrid::configure(target);
       }
     geometry = target;
-  
-    if(chaosmode && bounded) chaosmode = 0;
-    if(chaosmode == 1 && walls_not_implemented()) chaosmode = 0;
-
+    
     #if CAP_IRR
     if(IRREGULAR) variation = eVariation::bitruncated;
     #endif
@@ -1395,7 +1389,7 @@ EX void switch_game_mode(char switchWhat) {
     case rg::chaos:
       if(tactic::on) firstland = laIce;
       yendor::on = tactic::on = princess::challenge = false;
-      chaosmode = !chaosmode;
+      land_structure = ls::any_chaos() ? lsNiceWalls : lsChaos;
       if(bounded) set_geometry(gNormal);
       racing::on = false;
       break;
@@ -1406,7 +1400,8 @@ EX void switch_game_mode(char switchWhat) {
       geometry = gNormal;
       yendor::on = tactic::on = princess::challenge = peace::on = inv::on = false;
       dual::disable();
-      chaosmode = randomPatternsMode = false;
+      land_structure = lsNiceWalls;
+      randomPatternsMode = false;
       variation = eVariation::bitruncated;
       #if CAP_GP
       gp::param = gp::loc(1, 1);
@@ -1424,7 +1419,7 @@ EX void switch_game_mode(char switchWhat) {
       inv::on = false;
       princess::challenge = false;
       randomPatternsMode = false;
-      chaosmode = false;
+      land_structure = lsNiceWalls;
       racing::on = false;
       if(!yendor::on) firstland = laIce;
       dual::disable();
@@ -1437,7 +1432,7 @@ EX void switch_game_mode(char switchWhat) {
       peace::on = false;
       tour::on = false;
       inv::on = false;
-      chaosmode = false;
+      land_structure = lsSingle;
       princess::challenge = false;
       dual::disable();
       break;
@@ -1451,7 +1446,7 @@ EX void switch_game_mode(char switchWhat) {
       randomPatternsMode = false;
       princess::challenge = false;
       racing::on = false;
-      chaosmode = false;
+      land_structure = tactic::on ? lsSingle : lsNiceWalls;
       if(!tactic::on) firstland = laIce;
       dual::disable();
       break;
@@ -1476,7 +1471,7 @@ EX void switch_game_mode(char switchWhat) {
       shmup::on = false;
       tactic::on = false;
       yendor::on = false;
-      chaosmode = false;
+      land_structure = princess::challenge ? lsSingle : lsNiceWalls;
       inv::on = false;
       racing::on = false;
       dual::disable();
diff --git a/yendor.cpp b/yendor.cpp
index 012a3d9e..029206d0 100644
--- a/yendor.cpp
+++ b/yendor.cpp
@@ -541,6 +541,14 @@ EX namespace yendor {
         }
       }
     }
+
+  EX eLandStructure get_land_structure() {
+    if(clev().flags & YF_CHAOS)
+      return lsChaos;
+    if(clev().l == laWhirlpool)
+      return lsSingle;
+    return lsNiceWalls;
+    }
   
   EX void init(int phase) {
     if(!on) return;
@@ -548,7 +556,7 @@ EX namespace yendor {
     if(phase == 1) {
       won = false;
       if(!easy) items[itOrbYendor] = bestscore[modecode()][challenge];
-      chaosmode = (clev().flags & YF_CHAOS) ? 1 : 0;
+      land_structure = get_land_structure();
       specialland = clev().l;
       if(clev().flags & YF_START_AL) {
         specialland = laAlchemist;
@@ -1064,7 +1072,7 @@ void save_mode_data(hstream& f) {
   if(yendor::on) 
     f.write<char>(0);
   else
-    f.write<char>(chaosmode);
+    f.write<char>(land_structure);
   f.write<char>(shmup::on);
   f.write<char>(inv::on);
   #if CAP_TOUR