//-----------------------------------------------------------------------------
// Purpose: Recurses an entity hierarchy and fills out a list of all entities
//			in the hierarchy with their current origins and angles.
//
//			This list is necessary to keep lazy updates of abs origins and angles
//			from messing up our child/constrained entity fixup.
//-----------------------------------------------------------------------------
static void BuildTeleportList_r( CBaseEntity *pTeleport, CUtlVector<TeleportListEntry_t> &teleportList )
{
	TeleportListEntry_t entry;
	
	entry.pEntity = pTeleport;
	entry.prevAbsOrigin = pTeleport->GetAbsOrigin();
	entry.prevAbsAngles = pTeleport->GetAbsAngles();

	teleportList.AddToTail( entry );

	CBaseEntity *pList = pTeleport->FirstMoveChild();
	while ( pList )
	{
		BuildTeleportList_r( pList, teleportList );
		pList = pList->NextMovePeer();
	}
}


static CUtlVector<CBaseEntity *> g_TeleportStack;
void CBaseEntity::Teleport( const Vector *newPosition, const QAngle *newAngles, const Vector *newVelocity )
{
	if ( g_TeleportStack.Find( this ) >= 0 )
		return;
	int index = g_TeleportStack.AddToTail( this );

	CUtlVector<TeleportListEntry_t> teleportList;
	BuildTeleportList_r( this, teleportList );

	int i;
	for ( i = 0; i < teleportList.Count(); i++)
	{
		TeleportEntity( this, teleportList[i], newPosition, newAngles, newVelocity );
	}

	for (i = 0; i < teleportList.Count(); i++)
	{
		teleportList[i].pEntity->CollisionRulesChanged();
	}

	Assert( g_TeleportStack[index] == this );
	g_TeleportStack.FastRemove( index );

	// FIXME: add an initializer function to StepSimulationData
	StepSimulationData *step = ( StepSimulationData * )GetDataObject( STEPSIMULATION );
	if (step)
	{
		Q_memset( step, 0, sizeof( *step ) );
	}
}