added contact normal; fix for floor offset

panda/src/collide/collisionHandlerGravity.I

@@ -107,6 +107,16 @@ get_impact_velocity() const {
   return _impact_velocity;
 }
 
+////////////////////////////////////////////////////////////////////
+//    Function : CollisionHandlerGravity::get_contact_normal
+//      Access : Public
+// Description : 
+////////////////////////////////////////////////////////////////////
+INLINE const LVector3f &CollisionHandlerGravity::
+get_contact_normal() const {
+  return _contact_normal;
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: CollisionHandlerGravity::add_velocity
 //       Access: Public

panda/src/collide/collisionHandlerGravity.cxx

@@ -39,6 +39,7 @@ CollisionHandlerGravity() {
   _gravity = 32.174f;
   _current_velocity = 0.0f;
   _max_velocity = 400.0f;
+  _contact_normal = LVector3f::zero();
 }
 
 ////////////////////////////////////////////////////////////////////
@@ -179,6 +180,22 @@ set_highest_collision(const NodePath &target_node_path, const NodePath &from_nod
   // Add only the one that we're impacting with:
   add_entry(highest);
   
+  // Set the contact normal so that other code can make use of the
+  // surface slope:
+  if (highest->get_into()->is_of_type(CollisionPlane::get_class_type())) {
+    // This is asking: what is the normal of the plane that the avatar
+    // is colliding with relative to the avatar.  A positive y valye means
+    // the avatar is facing downhill and a negative y value means the
+    // avatar is facing uphill.
+    _contact_normal = DCAST(CollisionPlane, highest->get_into())->get_normal() * from_node_path.get_mat(highest->get_into_node_path());
+    //_contact_normal = DCAST(CollisionPlane, highest->get_into())->get_normal();
+    // This is asking: what is the normal of the avatar that the avatar
+    // is colliding with relative to the plane.
+    //_contact_normal = DCAST(CollisionPlane, highest->get_into())->get_normal() * highest->get_into_node_path().get_mat(from_node_path);
+  } else {
+    _contact_normal = highest->get_surface_normal(from_node_path);
+  }
+  
   return max_height;
 }
 #endif
@@ -247,7 +264,7 @@ handle_entries() {
           }
           _current_velocity -= _gravity * dt;
           // Record the airborne height in case someone else needs it: 
-          _airborne_height = -max_height + adjust;
+          _airborne_height = -(max_height + _offset) + adjust;
           assert(_airborne_height>=0.0f);
         }
 

panda/src/collide/collisionHandlerGravity.h

@@ -46,6 +46,7 @@ PUBLISHED:
   INLINE float get_airborne_height() const;
   INLINE bool is_on_ground() const;
   INLINE float get_impact_velocity() const;
+  INLINE const LVector3f &get_contact_normal() const;
 
   INLINE void add_velocity(float velocity);
   INLINE void set_velocity(float velocity);
@@ -70,6 +71,7 @@ private:
   float _gravity;
   float _current_velocity;
   float _max_velocity;
+  LVector3f _contact_normal;
 
 
 public: