fixed some bugs with which_copy -- now should consistently use the View coordinate system

celldrawer.cpp

@@ -1894,8 +1894,9 @@ void celldrawer::bookkeeping() {
     else {
       playerV = V * ddspin(c, cwt.spin, 0);
       if(cwt.mirrored) playerV = playerV * Mirror;
-      if((!confusingGeometry() && !fake::split() && !inmirrorcount) || eqmatrix(unshift(V), current_display->which_copy, 1e-2))
+      transmatrix F = back_to_view(V);
-        current_display->which_copy = unshift(V);
+      if((!confusingGeometry() && !fake::split() && !inmirrorcount) || eqmatrix(F, current_display->which_copy, 1e-2))
+        current_display->which_copy = F;
       if(orig) cwtV = playerV;
       }
     }

hypgraph.cpp

@@ -1868,6 +1868,27 @@ EX void spinEdge(ld aspd) {
   rotate_view(spin(downspin));
   }
 
+/** \brief convert a shiftmatrix to the coordinate system of View 
+ *  usually used to set which_copy
+ */
+EX transmatrix back_to_view(const shiftmatrix& V) {
+  // ortho_inverse does not work in 2.5D, iso_inverse does not work in Nil. 
+  // just use inverse
+  return inverse(actual_view_transform) * unshift(V);
+  }
+
+EX void fix_whichcopy(cell *c) {
+  if(!gmatrix.count(cwt.at)) return;
+  current_display->which_copy = back_to_view(gmatrix[c]);
+  }    
+
+void fix_whichcopy_if_near() {
+  if(!gmatrix.count(cwt.at)) return;
+  transmatrix T = back_to_view(gmatrix[cwt.at]);
+  if(!eqmatrix(T, current_display->which_copy)) return;
+  current_display->which_copy = T;
+  }
+
 EX void centerpc(ld aspd) {
 
   if(subscreens::split([=] () {centerpc(aspd);})) return;
@@ -1928,9 +1949,8 @@ EX void centerpc(ld aspd) {
     if(sl || vid.eye) T = T * zpush(cgi.SLEV[sl] - cgi.FLOOR + vid.eye);
     }
   #endif
-  // ortho_inverse does not work in 2.5D, iso_inverse does not work in Nil. 
+  
-  // just use inverse
+  hyperpoint H = tC0(T);
-  hyperpoint H = inverse(actual_view_transform) * tC0(T);
   ld R = (zero_d(GDIM, H) && !prod) ? 0 : hdist0(H);
   if(R < 1e-9) {
     // either already centered or direction unknown
@@ -1939,16 +1959,14 @@ EX void centerpc(ld aspd) {
       } */
     spinEdge(aspd);
     fixmatrix(View);
-    if(gmatrix.count(cwt.at))
+    fix_whichcopy(cwt.at);
-      current_display->which_copy = unshift(gmatrix[cwt.at]);
+    fixmatrix(current_display->which_copy);
     }
   
   else {
     aspd *= euclid ? (2+3*R*R) : (1+R+(shmup::on?1:0));
 
-    if(R < aspd && gmatrix.count(cwt.at) && eqmatrix(unshift(gmatrix[cwt.at]), current_display->which_copy)) {
+    if(R < aspd) fix_whichcopy_if_near();
-      current_display->which_copy = unshift(gmatrix[cwt.at]);
-      }
     
     if(R < aspd) 
       shift_view_to(shiftless(H));

orbs.cpp

@@ -623,7 +623,7 @@ EX void teleportTo(cell *dest) {
   cell *from = cwt.at;
   movecost(from, dest, 1);
   playerMoveEffects(movei(cwt.at, dest, TELEPORT));
-  current_display->which_copy = unshift(ggmatrix(dest));
+  fix_whichcopy(dest);
   cwt.at = dest; cwt.spin = hrand(dest->type); flipplayer = !!(hrand(2));
   drainOrb(itOrbTeleport);
 
@@ -713,7 +713,7 @@ EX bool jumpTo(orbAction a, cell *dest, eItem byWhat, int bonuskill IS(0), eMons
   
   changes.commit();
 
-  current_display->which_copy = unshift(ggmatrix(dest));
+  fix_whichcopy(dest);
   countLocalTreasure();
   
   for(int i=9; i>=0; i--)

shmup.cpp

@@ -196,7 +196,7 @@ void monster::rebasePat(const shiftmatrix& new_pat, cell *c2) {
     fix_to_2(at);
     pat = shiftless(at);
     if(multi::players == 1 && this == shmup::pc[0])
-      current_display->which_copy = unshift(ggmatrix(base));
+      current_display->which_copy = back_to_view(ggmatrix(base));
     return;
     }
   if(quotient || fake::split()) {