tracking the specific copy of the player in confusing geometries

basegraph.cpp

@@ -47,6 +47,8 @@ struct display_data {
   void set_mask(int ed);
 
   void set_all(int ed);
+  /** Which copy of the player cell? */
+  transmatrix which_copy;
   };
 
 #define View (::hr::current_display->view_matrix)

celldrawer.cpp

@@ -1713,6 +1713,8 @@ void celldrawer::bookkeeping() {
     else {
       playerV = V * ddspin(c, cwt.spin, 0);
       if(cwt.mirrored) playerV = playerV * Mirror;
+      if(!confusingGeometry() || eqmatrix(V, current_display->which_copy, 1e-2))
+        current_display->which_copy = V;
       if(orig) cwtV = playerV;
       }
     }

game.cpp

@@ -6660,6 +6660,7 @@ EX bool activateRecall() {
   // local_perspective = recallDisplay.local_perspective;
   gmatrix = recallDisplay.cellmatrices;
   gmatrix0 = recallDisplay.old_cellmatrices;
+  current_display->which_copy = recallDisplay.which_copy;
 
   makeEmpty(cwt.at);
   forCellEx(c2, cwt.at) 
@@ -8628,6 +8629,7 @@ EX bool movepcto(int d, int subdir IS(1), bool checkonly IS(false)) {
         }
       else
         animateMovement(mi, LAYER_SMALL);
+      current_display->which_copy = current_display->which_copy * adj(mi);
       
       mirror::act(origd, mirror::SPINMULTI | mirror::ATTACK | mirror::GO);
 

graph.cpp

@@ -3919,6 +3919,8 @@ EX void drawMarkers() {
 
   if(!(cmode & sm::NORMAL)) return;
   
+  queuepolyat(current_display->which_copy, cgi.shAsymmetric, 0xC0C0C0FF, PPR::SUPERLINE);
+  
   callhooks(hooks_markers);
   #if CAP_SHAPES
   viewmat();

hypgraph.cpp

@@ -1379,10 +1379,21 @@ EX void centerpc(ld aspd) {
   if(vid.sspeed >= 4.99) aspd = 1000;
   DEBBI(DF_GRAPH, ("center pc"));
 
-  ors::unrotate(cwtV); ors::unrotate(View);
-  if(invalid_matrix(cwtV)) return;
+  auto& W = current_display->which_copy;                                                            
+  ors::unrotate(W); ors::unrotate(View); ors::unrotate(cwtV);
+
+  /* what should we center? */
+  transmatrix T;
+  if(multi::players > 1) 
+    T = cwtV; /* do not even try */
+  else {
+    T = W;
+    if(shmup::on)
+      T = T * shmup::pc[0]->at;
+    }
+  
+  if(invalid_matrix(T)) return;
   
-  transmatrix T = cwtV;
   #if MAXMDIM >= 4
   if(GDIM == 3 && WDIM == 2) {
     geom3::do_auto_eye();
@@ -1412,10 +1423,11 @@ EX void centerpc(ld aspd) {
       shift_view_towards(H, aspd);
       
     fixmatrix(View);
+    fixmatrix(current_display->which_copy);
     spinEdge(aspd);
     }
 
-  ors::rerotate(cwtV); ors::rerotate(View);
+  ors::rerotate(W); ors::rerotate(cwtV); ors::rerotate(View);
   }
 
 EX void optimizeview() {
@@ -1477,6 +1489,7 @@ EX void resetview() {
     View = Id;
     }
   cwtV = View;
+  current_display->which_copy = View;
   // SDL_LockSurface(s);
   // SDL_UnlockSurface(s);
   }
@@ -2066,6 +2079,7 @@ EX transmatrix& get_view_orientation() {
 EX void rotate_view(transmatrix T) {
   transmatrix& which = get_view_orientation();
   which = T * which;
+  if(&which == &View) current_display->which_copy = T * current_display->which_copy;
   }
 
 /** shift the view according to the given tangent vector */
@@ -2086,17 +2100,24 @@ EX transmatrix get_shift_view_of(const hyperpoint H, const transmatrix V) {
 
 /** shift the view according to the given tangent vector */
 EX void shift_view(hyperpoint H) {
+  current_display->which_copy = get_shift_view_of(H, current_display->which_copy);
   View = get_shift_view_of(H, View);
   }
 
+void multiply_view(transmatrix T) {
+  View = T * View;
+  auto& wc = current_display->which_copy;
+  wc = T * wc;
+  }
+
 EX void shift_view_to(hyperpoint H) {
-  if(!nonisotropic) View = gpushxto0(H) * View;
+  if(!nonisotropic) multiply_view(gpushxto0(H));
   else shift_view(-inverse_exp(H, iTable, false));
   }
 
 EX void shift_view_towards(hyperpoint H, ld l) {
   if(!nonisotropic && !prod) 
-    View = rspintox(H) * xpush(-l) * spintox(H) * View;
+    multiply_view(rspintox(H) * xpush(-l) * spintox(H));
   else if(nonisotropic && !nisot::geodesic_movement)
     shift_view(tangent_length(H-C0, -l));
   else {

orbs.cpp

@@ -558,6 +558,7 @@ void teleportTo(cell *dest) {
   cell *from = cwt.at;
   movecost(from, dest, 1);
   playerMoveEffects(cwt.at, dest);
+  current_display->which_copy = ggmatrix(dest);
   cwt.at = dest; cwt.spin = hrand(dest->type); flipplayer = !!(hrand(2));
   drainOrb(itOrbTeleport);
 
@@ -602,6 +603,7 @@ EX void jumpTo(cell *dest, eItem byWhat, int bonuskill IS(0), eMonster dashmon I
 
   cell *c1 = cwt.at;
   animateMovement(match(cwt.at, dest), LAYER_SMALL);
+  current_display->which_copy = ggmatrix(dest);
   cwt.at = dest; 
   forCellIdEx(c2, i, dest) if(c2->cpdist < dest->cpdist) {
     cwt.spin = i;

shmup.cpp

@@ -172,10 +172,13 @@ void monster::rebasePat(const transmatrix& new_pat, cell *c2) {
     virtualRebase(this);
     fix_to_2(at);
     pat = at;
+    if(multi::players == 1 && this == shmup::pc[0])
+      current_display->which_copy = ggmatrix(base);
     return;
     }
   if(quotient) {
     at = inverse(gmatrix[base]) * new_pat;
+    transmatrix old_at = at;
     virtualRebase(this);
     fix_to_2(at);
     if(base != c2) {
@@ -183,8 +186,12 @@ void monster::rebasePat(const transmatrix& new_pat, cell *c2) {
       base = c2;
       at = inverse(T) * at;
       }
+    if(multi::players == 1 && this == shmup::pc[0] && !eqmatrix(old_at, at))
+      current_display->which_copy = current_display->which_copy * old_at * inverse(at);
     return;
     }
+  if(multi::players == 1 && this == shmup::pc[0])
+    current_display->which_copy = current_display->which_copy * inverse(gmatrix[base]) * gmatrix[c2];
   pat = new_pat;
   // if(c2 != base) printf("rebase %p -> %p\n", base, c2);
   base = c2;