From 7086723c67113e6db5bf3ebde137b0396945bfba Mon Sep 17 00:00:00 2001
From: David Rose <david@ddrose.com>
Date: Wed, 10 Dec 2003 00:31:07 +0000
Subject: [PATCH] throw on-floor events only for topmost object

---
 panda/src/collide/collisionHandlerEvent.h      |  2 +-
 panda/src/collide/collisionHandlerFloor.cxx    | 13 ++++++++++++-
 panda/src/collide/collisionHandlerPhysical.cxx |  3 ++-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/panda/src/collide/collisionHandlerEvent.h b/panda/src/collide/collisionHandlerEvent.h
index a7d3d91f86..51e6248543 100644
--- a/panda/src/collide/collisionHandlerEvent.h
+++ b/panda/src/collide/collisionHandlerEvent.h
@@ -67,7 +67,7 @@ PUBLISHED:
 
   void clear();
 
-private:
+protected:
   void throw_event_for(const vector_string &patterns, CollisionEntry *entry);
   void throw_event_pattern(const string &pattern, CollisionEntry *entry);
 
diff --git a/panda/src/collide/collisionHandlerFloor.cxx b/panda/src/collide/collisionHandlerFloor.cxx
index e9e66291e7..8fa1a363a2 100644
--- a/panda/src/collide/collisionHandlerFloor.cxx
+++ b/panda/src/collide/collisionHandlerFloor.cxx
@@ -60,6 +60,11 @@ bool CollisionHandlerFloor::
 handle_entries() {
   bool okflag = true;
 
+  // Reset the set of things our parent class CollisionHandlerEvent
+  // recorded a collision with.  We'll only consider ourselves
+  // collided with the topmost object for each from_entry.
+  _current_colliding.clear();
+
   FromEntries::const_iterator fi;
   for (fi = _from_entries.begin(); fi != _from_entries.end(); ++fi) {
     const NodePath &from_node_path = (*fi).first;
@@ -81,6 +86,7 @@ handle_entries() {
         // Get the maximum height for all collisions with this node.
         bool got_max = false;
         float max_height = 0.0f;
+        CollisionEntry *max_entry = NULL;
         
         Entries::const_iterator ei;
         for (ei = entries.begin(); ei != entries.end(); ++ei) {
@@ -99,10 +105,15 @@ handle_entries() {
             if (!got_max || height > max_height) {
               got_max = true;
               max_height = height;
+              max_entry = entry;
             }
           }
         }
-        
+
+        // Record a collision with the topmost element for the
+        // CollisionHandlerEvent base class.
+        _current_colliding.insert(max_entry);
+
         // Now set our height accordingly.
         float adjust = max_height + _offset;
         if (!IS_THRESHOLD_ZERO(adjust, 0.001)) {
diff --git a/panda/src/collide/collisionHandlerPhysical.cxx b/panda/src/collide/collisionHandlerPhysical.cxx
index d3d6eea49c..e784290fa3 100644
--- a/panda/src/collide/collisionHandlerPhysical.cxx
+++ b/panda/src/collide/collisionHandlerPhysical.cxx
@@ -83,9 +83,10 @@ add_entry(CollisionEntry *entry) {
 ////////////////////////////////////////////////////////////////////
 bool CollisionHandlerPhysical::
 end_group() {
+  bool result = handle_entries();
   CollisionHandlerEvent::end_group();
 
-  return handle_entries();
+  return result;
 }
 
 ////////////////////////////////////////////////////////////////////