diff --git a/panda/src/collide/collisionHandlerPhysical.I b/panda/src/collide/collisionHandlerPhysical.I
index 0e1b431d47..46983803cc 100644
--- a/panda/src/collide/collisionHandlerPhysical.I
+++ b/panda/src/collide/collisionHandlerPhysical.I
@@ -17,6 +17,52 @@
 ////////////////////////////////////////////////////////////////////
 
 
+////////////////////////////////////////////////////////////////////
+//     Function: CollisionHandlerPhysical::set_center
+//       Access: Published
+//  Description: Specifies an arbitrary NodePath that the handler is
+//               always considered to be facing.  It does not detect
+//               collisions with surfaces that appear to be facing
+//               away from this NodePath.  This works best when the
+//               collision surfaces in question are polygons.
+////////////////////////////////////////////////////////////////////
+INLINE void CollisionHandlerPhysical::
+set_center(const NodePath &center) {
+  _center = center;
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: CollisionHandlerPhysical::clear_center
+//       Access: Published
+//  Description: Clears the center NodePath specified with set_center.
+////////////////////////////////////////////////////////////////////
+INLINE void CollisionHandlerPhysical::
+clear_center() {
+  _center = NodePath();
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: CollisionHandlerPhysical::get_center
+//       Access: Published
+//  Description: Returns the NodePath specified with set_center, or
+//               the empty NodePath if nothing has been specified.
+////////////////////////////////////////////////////////////////////
+INLINE const NodePath &CollisionHandlerPhysical::
+get_center() const {
+  return _center;
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: CollisionHandlerPhysical::has_center
+//       Access: Published
+//  Description: Returns true if a NodePath has been specified with
+//               set_center(), false otherwise.
+////////////////////////////////////////////////////////////////////
+INLINE bool CollisionHandlerPhysical::
+has_center() const {
+  return !_center.is_empty();
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: CollisionHandlerPhysical::ColliderDef::set_target
 //       Access: Public
diff --git a/panda/src/collide/collisionHandlerPhysical.cxx b/panda/src/collide/collisionHandlerPhysical.cxx
index e784290fa3..5aa148937c 100644
--- a/panda/src/collide/collisionHandlerPhysical.cxx
+++ b/panda/src/collide/collisionHandlerPhysical.cxx
@@ -69,6 +69,21 @@ add_entry(CollisionEntry *entry) {
 
   if (entry->get_from()->is_tangible() &&
       (!entry->has_into() || entry->get_into()->is_tangible())) {
+
+    if (has_center()) {
+      // If a center is specified, we have to make sure the surface is
+      // more-or-less facing it.
+      if (!entry->has_surface_point() || !entry->has_surface_normal()) {
+        return;
+      }
+
+      LPoint3f point = entry->get_surface_point(_center);
+      LVector3f normal = entry->get_surface_normal(_center);
+       if (point.dot(normal) > 0) {
+         return;
+       }
+    }
+
     _from_entries[entry->get_from_node_path()].push_back(entry);
   }
 }
@@ -163,14 +178,3 @@ void CollisionHandlerPhysical::
 clear_colliders() {
   _colliders.clear();
 }
-
-////////////////////////////////////////////////////////////////////
-//     Function: CollisionHandlerPhysical::add_collider_node
-//       Access: Published
-//  Description: This method is deprecated and will shortly be removed
-//               in favor of the newer NodePath-based method, above.
-////////////////////////////////////////////////////////////////////
-void CollisionHandlerPhysical::
-add_collider_node(CollisionNode *node, PandaNode *target) {
-  add_collider(NodePath(node), NodePath(target));
-}
diff --git a/panda/src/collide/collisionHandlerPhysical.h b/panda/src/collide/collisionHandlerPhysical.h
index 28d21ea2ea..0513497af7 100644
--- a/panda/src/collide/collisionHandlerPhysical.h
+++ b/panda/src/collide/collisionHandlerPhysical.h
@@ -52,15 +52,12 @@ PUBLISHED:
   bool has_collider(const NodePath &collider) const;
   void clear_colliders();
 
-  // The following method is deprecated and exists only as a temporary
-  // transition to the above new NodePath-based methods.
-  void add_collider_node(CollisionNode *node, PandaNode *target);
+  INLINE void set_center(const NodePath &center);
+  INLINE void clear_center();
+  INLINE const NodePath &get_center() const;
+  INLINE bool has_center() const;
 
 protected:
-  typedef pvector< PT(CollisionEntry) > Entries;
-  typedef pmap<NodePath, Entries> FromEntries;
-  FromEntries _from_entries;
-
   class ColliderDef {
   public:
     INLINE void set_target(const NodePath &target,
@@ -71,11 +68,17 @@ protected:
     PT(DriveInterface) _drive_interface;
   };
 
+  virtual bool handle_entries()=0;
+  virtual void apply_linear_force(ColliderDef &def, const LVector3f &force)=0;
+
+  typedef pvector< PT(CollisionEntry) > Entries;
+  typedef pmap<NodePath, Entries> FromEntries;
+  FromEntries _from_entries;
+
   typedef pmap<NodePath, ColliderDef> Colliders;
   Colliders _colliders;
 
-  virtual bool handle_entries()=0;
-  virtual void apply_linear_force(ColliderDef &def, const LVector3f &force)=0;
+  NodePath _center;
 
 public:
   static TypeHandle get_class_type() {