diff --git a/cell.cpp b/cell.cpp
index 3e2448ec..a1da6f8c 100644
--- a/cell.cpp
+++ b/cell.cpp
@@ -1371,4 +1371,9 @@ EX int valence() {
   return S3;
   }
 
+/** portalspaces are not defined outside of a boundary */
+EX bool is_boundary(cell *c) {
+  return (cgflags & qPORTALSPACE) && isWall(c->wall);
+  }
+
 }
diff --git a/hypgraph.cpp b/hypgraph.cpp
index 2dafd989..b7978dc2 100644
--- a/hypgraph.cpp
+++ b/hypgraph.cpp
@@ -1955,6 +1955,8 @@ EX void centerpc(ld aspd) {
   ors::rerotate(W); ors::rerotate(cwtV.T); ors::rerotate(View);
   }
 
+EX transmatrix oView;
+
 EX void optimizeview() {
 
   if(subscreens::split(optimizeview)) return;
@@ -1971,6 +1973,11 @@ EX void optimizeview() {
     
   View = iview_inverse(iView);
   fixmatrix(View);
+  
+  if(is_boundary(centerover))
+    centerover = c, View = oView;
+  else
+    oView = View;
 
   #if CAP_ANIMATIONS
   if(centerover && inmirror(centerover)) {