diff --git a/history.cpp b/history.cpp
new file mode 100644
index 00000000..aaab18a9
--- /dev/null
+++ b/history.cpp
@@ -0,0 +1,653 @@
+// Hyperbolic Rogue -- the history mode
+// Copyright (C) 2011-2018 Zeno Rogue, see 'hyper.cpp' for details
+
+/** \file history.cpp
+ *  \brief Implementation of the history mode, including the long band and long spiral.
+ */
+
+namespace hr {
+
+#if CAP_SDL
+namespace spiral {
+
+  typedef long double ld;
+  typedef complex<long double> cxld;
+
+  int shiftx, shifty, velx, vely;
+
+  vector<pair<short, short> > quickmap;
+
+  int CX, CY, SX, SY, Yshift;
+  
+  vector<SDL_Surface*> band;
+  SDL_Surface *out;
+  
+  bool displayhelp = true;
+  
+  color_t& bandpixel(int x, int y) {
+    int i = 0;
+    while(i < isize(band) && x >= band[i]->w)
+      x -= band[i]->w, i++;
+    return qpixel(band[i], x, y);
+    }
+  
+  void precompute() {
+  
+    CX = 0;
+    for(int i=0; i<isize(band); i++) CX += band[i]->w;
+    if(CX == 0) { printf("ERROR: no CX\n"); return; }
+    CY = band[0]->h;
+    SX = out->w;
+    SY = out->h;
+
+    ld k = -2*M_PI*M_PI / log(2.6180339);
+
+//   cxld mnoznik = cxld(0, M_PI) / cxld(k, M_PI);
+
+    cxld factor = cxld(0, -CY/2/M_PI/M_PI) * cxld(k, M_PI);
+    
+    Yshift = CY * k / M_PI;
+    
+    quickmap.clear();
+    
+    double xc = ((SX | 1) - 2) / 2.;
+    double yc = ((SY | 1) - 2) / 2.;
+    
+    for(int y=0; y<SY; y++)
+    for(int x=0; x<SX; x++) {
+      cxld z(x-xc, y-yc);
+      cxld z1 = log(z);
+
+      z1 = z1 * factor;
+
+      quickmap.push_back(make_pair(int(real(z1)) % CX, int(imag(z1))));
+      }
+    }
+  
+  void draw() {
+    int c = 0;
+    for(int y=0; y<SY; y++) for(int x=0; x<SX; x++) {
+      pair<short,short> p = quickmap[c++];
+      int cx = p.first + shiftx;
+      int cy = p.second + + shifty;
+      int d = cy / CY;
+      cy -= d * CY; cx -= d * Yshift;
+      if(cy<0) cy += CY, cx += Yshift;
+      cx %= CX; if(cx<0) cx += CX;
+      qpixel(out, x, y) = bandpixel(cx, cy);
+      }
+    }
+
+  void loop(vector<SDL_Surface*> _band) {
+
+    band = _band;
+    out = s;
+    precompute();
+    if(CX == 0) return;
+    shiftx = shifty = 0;
+    velx=1; vely=1;
+    bool dosave = false;
+
+    bool saveGL = vid.usingGL;
+    if(saveGL) switchGL(); //  { vid.usingGL = false; setvideomode(); }
+
+    while(true) {
+
+      time_t timer;
+      timer = time(NULL);
+      char buf[128]; 
+      strftime(buf, 128, "spiral-%y%m%d-%H%M%S" IMAGEEXT, localtime(&timer));
+
+      SDL_LockSurface(s);
+      draw();
+      if(dosave) { dosave = false; IMAGESAVE(s, buf); }
+      SDL_UnlockSurface(s);
+      if(displayhelp) {
+        displaystr(SX/2, vid.fsize*2, 0, vid.fsize, "arrows = navigate, ESC = return, h = hide help", forecolor, 8);
+        displaystr(SX/2, SY - vid.fsize*2, 0, vid.fsize, XLAT("s = save to " IMAGEEXT, buf), forecolor, 8);
+        }
+      SDL_UpdateRect(s, 0, 0, 0, 0);  
+      shiftx += velx; shifty += vely;
+
+      SDL_Event event;
+      while(SDL_PollEvent(&event)) switch (event.type) {
+
+        case SDL_VIDEORESIZE: {
+          resize_screen_to(event.resize.w, event.resize.h);
+          precompute();
+          break;
+          }
+        case SDL_QUIT: case SDL_MOUSEBUTTONDOWN:
+          goto breakloop;
+
+        case SDL_KEYDOWN: {
+          int sym = event.key.keysym.sym;
+          int uni = event.key.keysym.unicode;
+          numlock_on = event.key.keysym.mod & KMOD_NUM;
+          if(DKEY == SDLK_RIGHT) velx++;
+          if(DKEY == SDLK_LEFT) velx--;
+          if(DKEY == SDLK_UP) vely++;
+          if(DKEY == SDLK_DOWN) vely--;
+          if(sym == SDLK_ESCAPE) goto breakloop;
+          if(uni == 'h') displayhelp = !displayhelp;
+          if(uni == 's') dosave = true;
+          }
+        }
+      }
+    
+    breakloop:
+    quickmap.clear();
+    if(saveGL) switchGL(); // { vid.usingGL = true; setvideomode(); }
+    }
+
+  }
+#endif
+
+EX namespace history {
+
+  void handleKeyC(int sym, int uni);
+  
+  int lastprogress;
+  
+  EX void progress_screen() {
+    gamescreen(0);
+    mouseovers = "";
+    }
+
+  EX void progress(string str) {
+#if CAP_SDL
+    int tick = SDL_GetTicks();
+    if(tick > lastprogress + 250) {
+      lastprogress = tick;
+      msgs.clear();
+      addMessage(str);
+      drawscreen();
+      }
+#endif
+    }
+  
+  EX bool on;
+  EX vector<shmup::monster*> v;
+  int llv;
+  EX double phase;
+  
+  EX vector<pair<cell*, eMonster> > killhistory;
+  EX vector<pair<cell*, eItem> > findhistory;
+  EX vector<cell*> movehistory;
+  
+  EX bool includeHistory;
+  EX ld lvspeed = 1;
+  EX int bandhalf = 200;
+  EX int bandsegment = 16000;
+
+  EX bool autoband = false;
+  EX bool autobandhistory = false;
+  EX bool dospiral = true;
+  
+  EX ld extra_line_steps = 0;
+  
+  EX vector<cell*> path_for_lineanimation;
+
+  EX void clear() {
+    on = false;
+    int N = isize(v);
+    for(int i=0; i<N; i++) delete v[i];
+    v.resize(0);
+    }
+
+  EX void create(cell *start, cell *target, transmatrix last) {
+    
+    if(target == start && !(quotient && isize(path_for_lineanimation) > 1)) {
+      addMessage("Must go a distance from the starting point");
+      return;
+      }
+    
+    on = true;
+  
+    if(!quotient) try {
+      path_for_lineanimation = build_shortest_path(start, target);
+      }
+    catch(hr_shortest_path_exception&) {
+      addMessage("Error: could not build a path");
+      return;
+      }
+
+    for(cell *c: path_for_lineanimation) {
+      shmup::monster *m = new shmup::monster;
+      m->at = Id;
+      m->base = c;
+      v.push_back(m);
+      }
+    
+    v.back()->at = last;
+  
+    int Q = isize(v)-1;
+    // virtualRebase(v[0], false);
+    // virtualRebase(v[Q], false);
+  
+    for(int i=0; i<1000; i++) {
+      progress(XLAT("Preparing the line (%1/1000)...", its(i+1)));
+
+      for(int j=1; j<Q; j++) if((j^i)&1) {
+      
+        // virtualRebase(v[j], false);
+        
+        hyperpoint prev = calc_relative_matrix(v[j-1]->base, v[j]->base, C0) *
+          v[j-1]->at * C0;
+
+        hyperpoint next = calc_relative_matrix(v[j+1]->base, v[j]->base, C0) * 
+          v[j+1]->at * C0;
+        
+        hyperpoint hmid = mid(prev, next);
+        
+        transmatrix at = rgpushxto0(hmid);
+
+        v[j]->at = at * rspintox(inverse(at) * next);
+        fixmatrix(v[j]->at);
+        }
+      }
+    
+    hyperpoint next0 = calc_relative_matrix(v[1]->base, v[0]->base, C0) * v[1]->at * C0;
+    v[0]->at = v[0]->at * rspintox(inverse(v[0]->at) * next0);
+    
+    llv = ticks;
+    phase = 0;
+    }
+
+  EX void create_playerpath() {
+    create(currentmap->gamestart(), cwt.at, Id);
+    }
+  
+  EX void create_recenter_to_view(bool precise) {
+    cell *c = centerover.at ? centerover.at : cwt.at;
+    create(path_for_lineanimation[0], c, precise ? inverse(ggmatrix(c)) : Id);
+    }
+  
+  EX void movetophase() {
+    
+    int ph = int(phase);
+    int siz = isize(v);
+    if(ph<0) ph = 0;
+    if(ph >= siz-1) ph = siz-2;
+    
+    heptagon *old = viewctr.at;
+    
+    viewctr.at = v[ph]->base->master;
+    viewctr.spin = 0;
+    
+    ld angle = 0;
+    if(WDIM == 3) {
+      hyperpoint h = inverse(models::rotmatrix()) * View * hpxy3(1,2,3);
+      angle = atan2(h[1], h[2]);
+      }
+    
+    View = inverse(master_relative(v[ph]->base) * v[ph]->at);
+  
+    hyperpoint now = v[ph]->at * C0;
+
+    hyperpoint next = calc_relative_matrix(v[ph+1]->base, v[ph]->base, C0) * 
+      v[ph+1]->at * C0;
+  
+    View = xpush(-(phase-ph) * hdist(now, next)) * View;
+    if(WDIM == 2) {
+      View = models::rotmatrix() * View;
+      }
+    else {
+      if(celldistance(v[ph]->base, old->c7) <= 2) {
+        hyperpoint h1 = View * currentmap->relative_matrix(old, viewctr.at) * hpxy3(1,2,3);
+        ld angle1 = atan2(h1[1], h1[2]);
+        View = cspin(2, 1, angle1 - angle) * View;
+        }
+      View = models::rotmatrix() * View;
+      }
+
+    playermoved = false;
+    centerover.at = v[ph]->base;
+    compute_graphical_distance();
+    }
+  
+  EX void apply() {
+    int t = ticks;
+    phase += (t-llv) * lvspeed / 400.;
+    llv = t;
+    
+    int siz = isize(v);
+    
+    while(phase > siz-1 + extra_line_steps) phase -= (siz + 2 * extra_line_steps-1);
+    while(phase < - extra_line_steps) phase += (siz + 2 * extra_line_steps-1);
+    
+    movetophase();
+    }
+  
+  ld measureLength() {
+    ld r = bandhalf * vid.scale;
+    
+    ld tpixels = 0;
+    int siz = isize(v);
+
+    for(int j=0; j<siz-1; j++) {
+      hyperpoint next = 
+        inverse(v[j]->at) *
+        calc_relative_matrix(v[j+1]->base, v[j]->base, C0) * 
+        v[j+1]->at * C0;
+        
+      hyperpoint nextscr;
+      applymodel(next, nextscr);
+      tpixels += nextscr[0] * r;
+      
+      if(j == 0 || j == siz-2)
+        tpixels += nextscr[0] * r * extra_line_steps;
+      }
+  
+    return tpixels;
+    }
+  
+  void restore();
+  void restoreBack();
+
+#if CAP_SDL
+  void createImage(bool dospiral) {
+    int segid = 1;
+    if(includeHistory) restore();
+  
+    int bandfull = 2*bandhalf;
+    ld len = measureLength();
+    
+    time_t timer;
+    timer = time(NULL);
+    char timebuf[128]; 
+    strftime(timebuf, 128, "%y%m%d-%H%M%S", localtime(&timer));
+
+    vector<SDL_Surface*> bands;
+    
+    resetbuffer rbuf;
+    
+    if(1) {
+      // block for RAII
+      dynamicval<videopar> dv(vid, vid);
+      dynamicval<ld> dr(models::rotation, 0);
+      dynamicval<bool> di(inHighQual, true);
+      
+      renderbuffer glbuf(bandfull, bandfull, vid.usingGL);
+      vid.xres = vid.yres = bandfull;
+      glbuf.enable(); current_display->radius = bandhalf;  
+      calcparam();
+      
+      ld xpos = 0;
+      
+      int seglen = min(int(len), bandsegment);
+      
+      SDL_Surface *band = SDL_CreateRGBSurface(SDL_SWSURFACE, seglen, bandfull,32,0,0,0,0);
+      
+      if(!band) {
+        addMessage("Could not create an image of that size.");
+        }
+      else {
+  
+        int siz = isize(v);
+        
+        int bonus = ceil(extra_line_steps);
+  
+        cell *last_base = NULL;
+        hyperpoint last_relative;
+        
+        for(int j=-bonus; j<siz+bonus; j++) {
+          /*
+          SDL_Surface *buffer = s;
+          s = sav; 
+          
+          pushScreen(progress_screen);
+  
+          char buf[128];
+          sprintf(buf, "#%03d", segid);
+  
+          progress(s0 + buf + " ("+its(j+bonus)+"/"+its(siz+bonus+bonus-1)+")"); */
+  
+          // calcparam(); current_display->radius = bandhalf;
+          phase = j; movetophase();
+      
+          glbuf.clear(backcolor);
+          drawfullmap();
+          
+          if(last_base) {
+            hyperpoint last = ggmatrix(last_base) * last_relative;
+            hyperpoint hscr;
+            applymodel(last, hscr);
+            ld bwidth = -current_display->radius * hscr[0];
+            print(hlog, "bwidth = ", bwidth, "/", len);
+  
+            drawsegment:
+            SDL_Surface *gr = glbuf.render();
+  
+            for(int cy=0; cy<bandfull; cy++) for(int cx=0; cx<=bwidth+3; cx++)
+              qpixel(band, int(xpos+cx), cy) = qpixel(gr, int(bandhalf+cx-bwidth), cy);
+            
+            if(j == 1-bonus)
+              xpos = bwidth * (extra_line_steps - bonus);
+        
+            if(xpos+bwidth > bandsegment) {
+              char buf[154];
+              sprintf(buf, "bandmodel-%s-%03d" IMAGEEXT, timebuf, segid++);
+    
+              IMAGESAVE(band, buf);
+    
+              if(dospiral) 
+                bands.push_back(band);
+              else 
+                SDL_FreeSurface(band);
+    
+              len -= bandsegment; xpos -= bandsegment;
+              seglen = min(int(len), bandsegment);
+              band = SDL_CreateRGBSurface(SDL_SWSURFACE, seglen, bandfull,32,0,0,0,0);
+              goto drawsegment;
+              }  
+            xpos += bwidth;      
+            }
+          
+          last_base = viewctr.at->c7;
+          last_relative = inverse(ggmatrix(last_base)) * C0;        
+          }
+        }
+
+      char buf[154];
+      sprintf(buf, "bandmodel-%s-%03d" IMAGEEXT, timebuf, segid++);
+      IMAGESAVE(band, buf);
+      addMessage(XLAT("Saved the band image as: ") + buf);
+  
+      if(dospiral) 
+        bands.push_back(band);
+      else 
+        SDL_FreeSurface(band);
+      }
+
+    rbuf.reset();
+
+    if(includeHistory) restoreBack();
+    
+    if(dospiral) {
+      spiral::loop(bands);
+      for(int i=0; i<isize(bands); i++) SDL_FreeSurface(bands[i]);
+      }
+    }
+#endif
+
+  EX bool band_renderable_now() {
+    return on && (pmodel == mdBand || pmodel == mdBandEquidistant || pmodel == mdBandEquiarea) && !euclid && !sphere;
+    }
+  
+  EX void history_menu() {
+    cmode = sm::SIDE | sm::MAYDARK;
+    gamescreen(0);
+    
+    dialog::init(XLAT("history mode"));
+
+    dialog::addBoolItem(XLAT("include history"), (includeHistory), 'i');
+    
+    // bool notconformal0 = (pmodel >= 5 && pmodel <= 6) && !euclid;
+    // bool notconformal = notconformal0 || abs(vid.alpha-1) > 1e-3;
+
+    dialog::addSelItem(XLAT("projection"), current_proj_name(), 'm');
+    
+    dialog::addBoolItem(XLAT("animate from start to current player position"), (on), 'e');
+    dialog::addBoolItem(XLAT("animate from last recenter to current view"), (on), 'E');
+    dialog::addBoolItem(XLAT("animate from last recenter to precise current view"), (on), 'E'-64);
+    if(on) dialog::addSelItem(XLAT("animation speed"), fts(lvspeed), 'a');
+    else dialog::addBreak(100);
+    dialog::addSelItem(XLAT("extend the ends"), fts(extra_line_steps), 'p');
+    
+#if CAP_SDL
+    dialog::addBoolItem(XLAT("render bands automatically"), (autoband), 'o');
+    if(autoband)
+      dialog::addBoolItem(XLAT("include history when auto-rendering"), (autobandhistory), 'j');
+    
+    if(band_renderable_now() || autoband) {
+      dialog::addSelItem(XLAT("band width"), "2*"+its(bandhalf), 'd');
+      dialog::addSelItem(XLAT("length of a segment"), its(bandsegment), 's');
+      dialog::addBoolItem(XLAT("spiral on rendering"), (dospiral), 'g');
+      if(band_renderable_now())
+        dialog::addItem(XLAT("render now (length: %1)", fts(measureLength())), 'f');
+      }
+#endif
+      
+    dialog::addBack();
+    dialog::display();
+    mouseovers = XLAT("see http://www.roguetemple.com/z/hyper/models.php");
+    keyhandler = handleKeyC;
+    }
+
+  void handleKeyC(int sym, int uni) {
+    dialog::handleNavigation(sym, uni);
+  
+    if(uni == 'e' || uni == 'E' || uni == 'E'-64) {
+      if(on) clear();
+      else {
+        if(canmove && !cheater) {
+          addMessage("Enable cheat mode or GAME OVER to use this");
+          return;
+          }
+        if(canmove && cheater) cheater++;
+        if(uni == 'E') create_recenter_to_view(false);
+        else if(uni == 'E'-64) create_recenter_to_view(true);
+        else create_playerpath();
+        }
+      }
+    else if(uni == 'o') 
+      autoband = !autoband;
+    else if(uni == 'm') 
+      pushScreen(models::model_menu);
+    else if(uni == 'a') 
+      dialog::editNumber(lvspeed, -5, 5, .1, 1, XLAT("animation speed"), "");
+    else if(uni == 'd') {
+      dialog::editNumber(bandhalf, 5, 1000, 5, 200, XLAT("band width"), "");
+      dialog::bound_low(5);
+      }
+    else if(uni == 's') {
+      dialog::editNumber(bandsegment, 500, 32000, 500, 16000, XLAT("band segment"), "");
+      dialog::bound_low(500);
+      }
+    else if(uni == 'p') 
+      dialog::editNumber(extra_line_steps, 0, 5, 1, 1, XLAT("extend the ends"), 
+        "0 = start at the game start, endat the end position; "
+        "larger numbers give extra space at the ends."
+        );
+    else if(uni == 'g') { dospiral = !dospiral; }
+    else if(uni == 'i') { 
+      if(canmove && !cheater) {
+        addMessage("Enable cheat mode or GAME OVER to use this");
+        return;
+        }
+      if(canmove && cheater) cheater++;
+      includeHistory = !includeHistory; 
+      }
+#if CAP_SDL
+    else if(uni == 'f' && band_renderable_now()) createImage(dospiral);
+#endif
+    else if(uni == 'j') { 
+      autobandhistory = !autobandhistory; 
+      }
+    else if(doexiton(sym, uni)) popScreen();
+    }
+  
+  set<cell*> inmovehistory, inkillhistory, infindhistory;
+  
+  EX void restore() {
+    inmovehistory.clear();
+    inkillhistory.clear();
+    infindhistory.clear();
+    for(int i=0; i<isize(movehistory); i++)
+      inmovehistory.insert(movehistory[i]);
+    int sk = isize(killhistory);
+    for(int i=0; i<sk; i++) {
+      eMonster m = killhistory[i].second;
+      killhistory[i].second = killhistory[i].first->monst;
+      killhistory[i].first->monst = m;
+      inkillhistory.insert(killhistory[i].first);
+      }
+    int si = isize(findhistory);
+    for(int i=0; i<si; i++) {
+      eItem m = findhistory[i].second;
+      findhistory[i].second = findhistory[i].first->item;
+      findhistory[i].first->item = m;
+      infindhistory.insert(findhistory[i].first);
+      }
+    }
+
+  EX void restoreBack() {
+    int sk = isize(killhistory);
+    for(int i=sk-1; i>=0; i--) {
+      eMonster m = killhistory[i].second;
+      killhistory[i].second = killhistory[i].first->monst;
+      killhistory[i].first->monst = m;
+      }
+    int si = isize(findhistory);
+    for(int i=si-1; i>=0; i--) {
+      eItem m = findhistory[i].second;
+      findhistory[i].second = findhistory[i].first->item;
+      findhistory[i].first->item = m;
+      }
+    }
+  
+  EX void renderAutoband() {
+#if CAP_SDL
+    if(!cwt.at || celldist(cwt.at) <= 7) return;
+    if(!autoband) return;
+    eModel spm = pmodel;
+    bool ih = includeHistory;
+    includeHistory = autobandhistory;
+    pmodel = mdBand;
+    create_playerpath();
+    createImage(dospiral);
+    clear();
+    pmodel = spm;
+    includeHistory = ih;
+#endif
+    }
+
+  #if CAP_COMMANDLINE
+  int readArgs() {
+    using namespace arg;
+             
+    if(0) ;
+    else if(argis("-playerpath")) {
+      history::create_playerpath();
+      }
+    else return 1;
+    return 0;
+    }
+
+  auto hookArg = addHook(hooks_args, 100, readArgs);
+  #endif  
+
+  auto hooks = addHook(clearmemory, 0, [] () {
+    history::renderAutoband();
+    history::on = false;
+    history::killhistory.clear();
+    history::findhistory.clear();
+    history::movehistory.clear();
+    history::path_for_lineanimation.clear();
+    history::includeHistory = false;
+    });
+
+  }
+
+}