// Filename: callbackNode.I
// Created by:  drose (13Mar09)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) Carnegie Mellon University.  All rights reserved.
//
// All use of this software is subject to the terms of the revised BSD
// license.  You should have received a copy of this license along
// with this source code in a file named "LICENSE."
//
////////////////////////////////////////////////////////////////////


////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::set_cull_callback
//       Access: Published
//  Description: Sets the CallbackObject that will be notified when
//               this node is visited during the cull traversal.  This
//               callback will be made during the cull thread.
//
//               The cull traversal is responsible for determining
//               which nodes are visible and within the view frustum,
//               and for accumulating state and transform, and
//               generally building up the list of CullableObjects
//               that are to be eventually passed to the draw
//               traversal for rendering.
//
//               At the time the cull traversal callback is made, the
//               node has been determined to be visible and it has
//               passed the bounding-volume test, so it lies within
//               the view frustum.
//
//               The callback is passed an instance of a
//               NodeCullCallbackData, which contains pointers to the
//               CullTraverser and CullTraverserData--enough data to
//               examine the current node and its place within the
//               scene graph.  The callback *replaces* the normal cull
//               behavior, so if your callback does nothing, the cull
//               traversal will not continue below this node.  If you
//               wish the cull traversal to continue to visit this
//               node and below, you must call cbdata->upcall()
//               from your callback.
////////////////////////////////////////////////////////////////////
INLINE void CallbackNode::
set_cull_callback(CallbackObject *object) {
  CDWriter cdata(_cycler);
  cdata->_cull_callback = object;
}

////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::clear_cull_callback
//       Access: Published
//  Description: Removes the callback set by an earlier call to
//               set_cull_callback().
////////////////////////////////////////////////////////////////////
INLINE void CallbackNode::
clear_cull_callback() {
  set_cull_callback(NULL);
}

////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::get_cull_callback
//       Access: Published
//  Description: Returns the CallbackObject set by set_cull_callback().
////////////////////////////////////////////////////////////////////
INLINE CallbackObject *CallbackNode::
get_cull_callback() const {
  CDReader cdata(_cycler);
  return cdata->_cull_callback;
}

////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::set_draw_callback
//       Access: Published
//  Description: Sets the CallbackObject that will be notified when
//               this node is visited during the draw traversal.  This
//               callback will be made during the draw thread.
//
//               The draw traversal is responsible for actually
//               issuing the commands to the graphics engine to draw
//               primitives.  Its job is to walk through the list of
//               CullableObjects build up by the cull traversal, as
//               quickly as possible, issuing the appropriate commands
//               to draw each one.
//
//               At the time the draw traversal callback is made, the
//               graphics state has been loaded with the correct
//               modelview transform and render state, and the
//               primitives (if any) in this node are ready to be
//               drawn.
//
//               The callback is passed an instance of a
//               GeomDrawCallbackData, which contains pointers to the
//               current state and transform, as well as the current
//               GSG.  There is a Geom pointer as well, but it will
//               always be NULL to this callback, since the
//               CallbackNode does not itself contain any Geoms.
////////////////////////////////////////////////////////////////////
INLINE void CallbackNode::
set_draw_callback(CallbackObject *object) {
  CDWriter cdata(_cycler);
  cdata->_draw_callback = object;
}

////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::clear_draw_callback
//       Access: Published
//  Description: Removes the callback set by an earlier call to
//               set_draw_callback().
////////////////////////////////////////////////////////////////////
INLINE void CallbackNode::
clear_draw_callback() {
  set_draw_callback(NULL);
}

////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::get_draw_callback
//       Access: Published
//  Description: Returns the CallbackObject set by set_draw_callback().
////////////////////////////////////////////////////////////////////
INLINE CallbackObject *CallbackNode::
get_draw_callback() const {
  CDReader cdata(_cycler);
  return cdata->_draw_callback;
}

////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::CData::Constructor
//       Access: Public
//  Description:
////////////////////////////////////////////////////////////////////
INLINE CallbackNode::CData::
CData() {
}

////////////////////////////////////////////////////////////////////
//     Function: CallbackNode::CData::Copy Constructor
//       Access: Public
//  Description:
////////////////////////////////////////////////////////////////////
INLINE CallbackNode::CData::
CData(const CallbackNode::CData &copy) :
  _cull_callback(copy._cull_callback),
  _draw_callback(copy._draw_callback)
{
}