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diff --git a/game/server/nav_pathfind.h b/game/server/nav_pathfind.h
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+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: 
+//
+// $NoKeywords: $
+//
+//=============================================================================//
+// nav_pathfind.h
+// Path-finding mechanisms using the Navigation Mesh
+// Author: Michael S. Booth ([email protected]), January 2003
+
+#ifndef _NAV_PATHFIND_H_
+#define _NAV_PATHFIND_H_
+
+#include "tier0/vprof.h"
+#include "mathlib/ssemath.h"
+#include "nav_area.h"
+
+#ifdef STAGING_ONLY
+extern int g_DebugPathfindCounter;
+#endif
+
+
+//-------------------------------------------------------------------------------------------------------------------
+/**
+ * Used when building a path to determine the kind of path to build
+ */
+enum RouteType
+{
+	DEFAULT_ROUTE,
+	FASTEST_ROUTE,
+	SAFEST_ROUTE,
+	RETREAT_ROUTE,
+};
+
+
+//--------------------------------------------------------------------------------------------------------------
+/**
+ * Functor used with NavAreaBuildPath()
+ */
+class ShortestPathCost
+{
+public:
+	float operator() ( CNavArea *area, CNavArea *fromArea, const CNavLadder *ladder, const CFuncElevator *elevator, float length )
+	{
+		if ( fromArea == NULL )
+		{
+			// first area in path, no cost
+			return 0.0f;
+		}
+		else
+		{
+			// compute distance traveled along path so far
+			float dist;
+
+			if ( ladder )
+			{
+				dist = ladder->m_length;
+			}
+			else if ( length > 0.0 )
+			{
+				dist = length;
+			}
+			else
+			{
+				dist = ( area->GetCenter() - fromArea->GetCenter() ).Length();
+			}
+
+			float cost = dist + fromArea->GetCostSoFar();
+
+			// if this is a "crouch" area, add penalty
+			if ( area->GetAttributes() & NAV_MESH_CROUCH )
+			{
+				const float crouchPenalty = 20.0f;		// 10
+				cost += crouchPenalty * dist;
+			}
+
+			// if this is a "jump" area, add penalty
+			if ( area->GetAttributes() & NAV_MESH_JUMP )
+			{
+				const float jumpPenalty = 5.0f;
+				cost += jumpPenalty * dist;
+			}
+
+			return cost;
+		}
+	}
+};
+
+//--------------------------------------------------------------------------------------------------------------
+/**
+ * Find path from startArea to goalArea via an A* search, using supplied cost heuristic.
+ * If cost functor returns -1 for an area, that area is considered a dead end.
+ * This doesn't actually build a path, but the path is defined by following parent
+ * pointers back from goalArea to startArea.
+ * If 'closestArea' is non-NULL, the closest area to the goal is returned (useful if the path fails).
+ * If 'goalArea' is NULL, will compute a path as close as possible to 'goalPos'.
+ * If 'goalPos' is NULL, will use the center of 'goalArea' as the goal position.
+ * If 'maxPathLength' is nonzero, path building will stop when this length is reached.
+ * Returns true if a path exists.
+ */
+#define IGNORE_NAV_BLOCKERS true
+template< typename CostFunctor >
+bool NavAreaBuildPath( CNavArea *startArea, CNavArea *goalArea, const Vector *goalPos, CostFunctor &costFunc, CNavArea **closestArea = NULL, float maxPathLength = 0.0f, int teamID = TEAM_ANY, bool ignoreNavBlockers = false )
+{
+	VPROF_BUDGET( "NavAreaBuildPath", "NextBotSpiky" );
+
+	if ( closestArea )
+	{
+		*closestArea = startArea;
+	}
+
+#ifdef STAGING_ONLY
+	bool isDebug = ( g_DebugPathfindCounter-- > 0 );
+#endif
+
+	if (startArea == NULL)
+		return false;
+
+	startArea->SetParent( NULL );
+
+	if (goalArea != NULL && goalArea->IsBlocked( teamID, ignoreNavBlockers ))
+		goalArea = NULL;
+
+	if (goalArea == NULL && goalPos == NULL)
+		return false;
+
+	// if we are already in the goal area, build trivial path
+	if (startArea == goalArea)
+	{
+		return true;
+	}
+
+	// determine actual goal position
+	Vector actualGoalPos = (goalPos) ? *goalPos : goalArea->GetCenter();
+
+	// start search
+	CNavArea::ClearSearchLists();
+
+	// compute estimate of path length
+	/// @todo Cost might work as "manhattan distance"
+	startArea->SetTotalCost( (startArea->GetCenter() - actualGoalPos).Length() );
+
+	float initCost = costFunc( startArea, NULL, NULL, NULL, -1.0f );	
+	if (initCost < 0.0f)
+		return false;
+	startArea->SetCostSoFar( initCost );
+	startArea->SetPathLengthSoFar( 0.0 );
+
+	startArea->AddToOpenList();
+
+	// keep track of the area we visit that is closest to the goal
+	float closestAreaDist = startArea->GetTotalCost();
+
+	// do A* search
+	while( !CNavArea::IsOpenListEmpty() )
+	{
+		// get next area to check
+		CNavArea *area = CNavArea::PopOpenList();
+
+#ifdef STAGING_ONLY
+		if ( isDebug )
+		{
+			area->DrawFilled( 0, 255, 0, 128, 30.0f );
+		}
+#endif
+
+		// don't consider blocked areas
+		if ( area->IsBlocked( teamID, ignoreNavBlockers ) )
+			continue;
+
+		// check if we have found the goal area or position
+		if (area == goalArea || (goalArea == NULL && goalPos && area->Contains( *goalPos )))
+		{
+			if (closestArea)
+			{
+				*closestArea = area;
+			}
+
+			return true;
+		}
+
+		// search adjacent areas
+		enum SearchType
+		{
+			SEARCH_FLOOR, SEARCH_LADDERS, SEARCH_ELEVATORS
+		};
+		SearchType searchWhere = SEARCH_FLOOR;
+		int searchIndex = 0;
+
+		int dir = NORTH;
+		const NavConnectVector *floorList = area->GetAdjacentAreas( NORTH );
+
+		bool ladderUp = true;
+		const NavLadderConnectVector *ladderList = NULL;
+		enum { AHEAD = 0, LEFT, RIGHT, BEHIND, NUM_TOP_DIRECTIONS };
+		int ladderTopDir = AHEAD;
+		bool bHaveMaxPathLength = ( maxPathLength > 0.0f );
+		float length = -1;
+		
+		while( true )
+		{
+			CNavArea *newArea = NULL;
+			NavTraverseType how;
+			const CNavLadder *ladder = NULL;
+			const CFuncElevator *elevator = NULL;
+
+			//
+			// Get next adjacent area - either on floor or via ladder
+			//
+			if ( searchWhere == SEARCH_FLOOR )
+			{
+				// if exhausted adjacent connections in current direction, begin checking next direction
+				if ( searchIndex >= floorList->Count() )
+				{
+					++dir;
+
+					if ( dir == NUM_DIRECTIONS )
+					{
+						// checked all directions on floor - check ladders next
+						searchWhere = SEARCH_LADDERS;
+
+						ladderList = area->GetLadders( CNavLadder::LADDER_UP );
+						searchIndex = 0;
+						ladderTopDir = AHEAD;
+					}
+					else
+					{
+						// start next direction
+						floorList = area->GetAdjacentAreas( (NavDirType)dir );
+						searchIndex = 0;
+					}
+
+					continue;
+				}
+
+				const NavConnect &floorConnect = floorList->Element( searchIndex );
+				newArea = floorConnect.area;
+				length = floorConnect.length;
+				how = (NavTraverseType)dir;
+				++searchIndex;
+
+				if ( IsX360() && searchIndex < floorList->Count() )
+				{
+					PREFETCH360( floorList->Element( searchIndex ).area, 0  );
+				}
+			}
+			else if ( searchWhere == SEARCH_LADDERS )
+			{
+				if ( searchIndex >= ladderList->Count() )
+				{
+					if ( !ladderUp )
+					{
+						// checked both ladder directions - check elevators next
+						searchWhere = SEARCH_ELEVATORS;
+						searchIndex = 0;
+						ladder = NULL;
+					}
+					else
+					{
+						// check down ladders
+						ladderUp = false;
+						ladderList = area->GetLadders( CNavLadder::LADDER_DOWN );
+						searchIndex = 0;
+					}
+					continue;
+				}
+
+				if ( ladderUp )
+				{
+					ladder = ladderList->Element( searchIndex ).ladder;
+
+					// do not use BEHIND connection, as its very hard to get to when going up a ladder
+					if ( ladderTopDir == AHEAD )
+					{
+						newArea = ladder->m_topForwardArea;
+					}
+					else if ( ladderTopDir == LEFT )
+					{
+						newArea = ladder->m_topLeftArea;
+					}
+					else if ( ladderTopDir == RIGHT )
+					{
+						newArea = ladder->m_topRightArea;
+					}
+					else
+					{
+						++searchIndex;
+						ladderTopDir = AHEAD;
+						continue;
+					}
+
+					how = GO_LADDER_UP;
+					++ladderTopDir;
+				}
+				else
+				{
+					newArea = ladderList->Element( searchIndex ).ladder->m_bottomArea;
+					how = GO_LADDER_DOWN;
+					ladder = ladderList->Element(searchIndex).ladder;
+					++searchIndex;
+				}
+
+				if ( newArea == NULL )
+					continue;
+
+				length = -1.0f;
+			}
+			else // if ( searchWhere == SEARCH_ELEVATORS )
+			{
+				const NavConnectVector &elevatorAreas = area->GetElevatorAreas();
+
+				elevator = area->GetElevator();
+
+				if ( elevator == NULL || searchIndex >= elevatorAreas.Count() )
+				{
+					// done searching connected areas
+					elevator = NULL;
+					break;
+				}
+
+				newArea = elevatorAreas[ searchIndex++ ].area;
+				if ( newArea->GetCenter().z > area->GetCenter().z )
+				{
+					how = GO_ELEVATOR_UP;
+				}
+				else
+				{
+					how = GO_ELEVATOR_DOWN;
+				}
+
+				length = -1.0f;
+			}
+
+
+			// don't backtrack
+			Assert( newArea );
+			if ( newArea == area->GetParent() )
+				continue;
+			if ( newArea == area ) // self neighbor?
+				continue;
+
+			// don't consider blocked areas
+			if ( newArea->IsBlocked( teamID, ignoreNavBlockers ) )
+				continue;
+
+			float newCostSoFar = costFunc( newArea, area, ladder, elevator, length );
+
+			// NaNs really mess this function up causing tough to track down hangs. If
+			//  we get inf back, clamp it down to a really high number.
+			DebuggerBreakOnNaN_StagingOnly( newCostSoFar );
+			if ( IS_NAN( newCostSoFar ) )
+				newCostSoFar = 1e30f;
+
+			// check if cost functor says this area is a dead-end
+			if ( newCostSoFar < 0.0f )
+				continue;
+
+			// Safety check against a bogus functor.  The cost of the path
+			// A...B, C should always be at least as big as the path A...B.
+			Assert( newCostSoFar >= area->GetCostSoFar() );
+
+			// And now that we've asserted, let's be a bit more defensive.
+			// Make sure that any jump to a new area incurs some pathfinsing
+			// cost, to avoid us spinning our wheels over insignificant cost
+			// benefit, floating point precision bug, or busted cost functor.
+			float minNewCostSoFar = area->GetCostSoFar() * 1.00001f + 0.00001f;
+			newCostSoFar = Max( newCostSoFar, minNewCostSoFar );
+				
+			// stop if path length limit reached
+			if ( bHaveMaxPathLength )
+			{
+				// keep track of path length so far
+				float deltaLength = ( newArea->GetCenter() - area->GetCenter() ).Length();
+				float newLengthSoFar = area->GetPathLengthSoFar() + deltaLength;
+				if ( newLengthSoFar > maxPathLength )
+					continue;
+				
+				newArea->SetPathLengthSoFar( newLengthSoFar );
+			}
+
+			if ( ( newArea->IsOpen() || newArea->IsClosed() ) && newArea->GetCostSoFar() <= newCostSoFar )
+			{
+				// this is a worse path - skip it
+				continue;
+			}
+			else
+			{
+				// compute estimate of distance left to go
+				float distSq = ( newArea->GetCenter() - actualGoalPos ).LengthSqr();
+				float newCostRemaining = ( distSq > 0.0 ) ? FastSqrt( distSq ) : 0.0 ;
+
+				// track closest area to goal in case path fails
+				if ( closestArea && newCostRemaining < closestAreaDist )
+				{
+					*closestArea = newArea;
+					closestAreaDist = newCostRemaining;
+				}
+				
+				newArea->SetCostSoFar( newCostSoFar );
+				newArea->SetTotalCost( newCostSoFar + newCostRemaining );
+
+				if ( newArea->IsClosed() )
+				{
+					newArea->RemoveFromClosedList();
+				}
+
+				if ( newArea->IsOpen() )
+				{
+					// area already on open list, update the list order to keep costs sorted
+					newArea->UpdateOnOpenList();
+				}
+				else
+				{
+					newArea->AddToOpenList();
+				}
+
+				newArea->SetParent( area, how );
+			}
+		}
+
+		// we have searched this area
+		area->AddToClosedList();
+	}
+
+	return false;
+}
+
+
+//--------------------------------------------------------------------------------------------------------------
+/**
+ * Compute distance between two areas. Return -1 if can't reach 'endArea' from 'startArea'.
+ */
+template< typename CostFunctor >
+float NavAreaTravelDistance( CNavArea *startArea, CNavArea *endArea, CostFunctor &costFunc, float maxPathLength = 0.0f )
+{
+	if (startArea == NULL)
+		return -1.0f;
+
+	if (endArea == NULL)
+		return -1.0f;
+
+	if (startArea == endArea)
+		return 0.0f;
+
+	// compute path between areas using given cost heuristic
+	if (NavAreaBuildPath( startArea, endArea, NULL, costFunc, NULL, maxPathLength ) == false)
+		return -1.0f;
+
+	// compute distance along path
+	float distance = 0.0f;
+	for( CNavArea *area = endArea; area->GetParent(); area = area->GetParent() )
+	{
+		distance += (area->GetCenter() - area->GetParent()->GetCenter()).Length();
+	}
+
+	return distance;
+}
+
+
+
+//--------------------------------------------------------------------------------------------------------------
+/**
+ * Do a breadth-first search, invoking functor on each area.
+ * If functor returns 'true', continue searching from this area. 
+ * If functor returns 'false', the area's adjacent areas are not explored (dead end).
+ * If 'maxRange' is 0 or less, no range check is done (all areas will be examined).
+ *
+ * NOTE: Returns all areas that overlap range, even partially
+ *
+ * @todo Use ladder connections
+ */
+
+// helper function
+inline void AddAreaToOpenList( CNavArea *area, CNavArea *parent, const Vector &startPos, float maxRange )
+{
+	if (area == NULL)
+		return;
+
+	if (!area->IsMarked())
+	{
+		area->Mark();
+		area->SetTotalCost( 0.0f );
+		area->SetParent( parent );
+
+		if (maxRange > 0.0f)
+		{
+			// make sure this area overlaps range
+			Vector closePos;
+			area->GetClosestPointOnArea( startPos, &closePos );
+			if ((closePos - startPos).AsVector2D().IsLengthLessThan( maxRange ))
+			{
+				// compute approximate distance along path to limit travel range, too
+				float distAlong = parent->GetCostSoFar();
+				distAlong += (area->GetCenter() - parent->GetCenter()).Length();
+				area->SetCostSoFar( distAlong );
+
+				// allow for some fudge due to large size areas
+				if (distAlong <= 1.5f * maxRange)
+					area->AddToOpenList();
+			}
+		}
+		else
+		{
+			// infinite range
+			area->AddToOpenList();
+		}
+	}
+}
+
+
+/****************************************************************
+ * DEPRECATED: Use filter-based SearchSurroundingAreas below
+ ****************************************************************/
+#define INCLUDE_INCOMING_CONNECTIONS	0x1
+#define INCLUDE_BLOCKED_AREAS			0x2
+#define EXCLUDE_OUTGOING_CONNECTIONS	0x4
+#define EXCLUDE_ELEVATORS				0x8
+template < typename Functor >
+void SearchSurroundingAreas( CNavArea *startArea, const Vector &startPos, Functor &func, float maxRange = -1.0f, unsigned int options = 0, int teamID = TEAM_ANY )
+{
+	if (startArea == NULL)
+		return;
+
+	CNavArea::MakeNewMarker();
+	CNavArea::ClearSearchLists();
+
+	startArea->AddToOpenList();
+	startArea->SetTotalCost( 0.0f );
+	startArea->SetCostSoFar( 0.0f );
+	startArea->SetParent( NULL );
+	startArea->Mark();
+
+	while( !CNavArea::IsOpenListEmpty() )
+	{
+		// get next area to check
+		CNavArea *area = CNavArea::PopOpenList();
+
+		// don't use blocked areas
+		if ( area->IsBlocked( teamID ) && !(options & INCLUDE_BLOCKED_AREAS) )
+			continue;
+
+		// invoke functor on area
+		if (func( area ))
+		{
+			// explore adjacent floor areas
+			for( int dir=0; dir<NUM_DIRECTIONS; ++dir )
+			{
+				int count = area->GetAdjacentCount( (NavDirType)dir );
+				for( int i=0; i<count; ++i )
+				{
+					CNavArea *adjArea = area->GetAdjacentArea( (NavDirType)dir, i );
+					if ( options & EXCLUDE_OUTGOING_CONNECTIONS )
+					{
+						if ( !adjArea->IsConnected( area, NUM_DIRECTIONS ) )
+						{
+							continue;	// skip this outgoing connection
+						}
+					}
+					
+					AddAreaToOpenList( adjArea, area, startPos, maxRange );
+				}
+			}
+			
+			// potentially include areas that connect TO this area via a one-way link
+			if (options & INCLUDE_INCOMING_CONNECTIONS)
+			{
+				for( int dir=0; dir<NUM_DIRECTIONS; ++dir )
+				{
+					const NavConnectVector *list = area->GetIncomingConnections( (NavDirType)dir );
+
+					FOR_EACH_VEC( (*list), it )
+					{
+						NavConnect connect = (*list)[ it ];				
+						
+						AddAreaToOpenList( connect.area, area, startPos, maxRange );
+					}
+				}
+			}
+
+
+			// explore adjacent areas connected by ladders
+
+			// check up ladders
+			const NavLadderConnectVector *ladderList = area->GetLadders( CNavLadder::LADDER_UP );
+			if (ladderList)
+			{
+				FOR_EACH_VEC( (*ladderList), it )
+				{
+					const CNavLadder *ladder = (*ladderList)[ it ].ladder;
+
+					// do not use BEHIND connection, as its very hard to get to when going up a ladder
+					AddAreaToOpenList( ladder->m_topForwardArea, area, startPos, maxRange );
+					AddAreaToOpenList( ladder->m_topLeftArea, area, startPos, maxRange );
+					AddAreaToOpenList( ladder->m_topRightArea, area, startPos, maxRange );
+				}
+			}
+
+			// check down ladders
+			ladderList = area->GetLadders( CNavLadder::LADDER_DOWN );
+			if (ladderList)
+			{
+				FOR_EACH_VEC( (*ladderList), it )
+				{
+					const CNavLadder *ladder = (*ladderList)[ it ].ladder;
+
+					AddAreaToOpenList( ladder->m_bottomArea, area, startPos, maxRange );
+				}
+			}
+
+			if ( (options & EXCLUDE_ELEVATORS) == 0 )
+			{
+				const NavConnectVector &elevatorList = area->GetElevatorAreas();
+				FOR_EACH_VEC( elevatorList, it )
+				{
+					CNavArea *elevatorArea = elevatorList[ it ].area;
+					AddAreaToOpenList( elevatorArea, area, startPos, maxRange );
+				}
+			}
+		}
+	}
+}
+
+
+//--------------------------------------------------------------------------------------------------------------
+/**
+ * Derive your own custom search functor from this interface method for use with SearchSurroundingAreas below.
+ */
+class ISearchSurroundingAreasFunctor
+{
+public:
+	virtual ~ISearchSurroundingAreasFunctor() { }
+
+	/**
+	 * Perform user-defined action on area.
+	 * Return 'false' to end the search (ie: you found what you were looking for)
+	 */
+	virtual bool operator() ( CNavArea *area, CNavArea *priorArea, float travelDistanceSoFar ) = 0;
+
+	// return true if 'adjArea' should be included in the ongoing search
+	virtual bool ShouldSearch( CNavArea *adjArea, CNavArea *currentArea, float travelDistanceSoFar ) 
+	{
+		return !adjArea->IsBlocked( TEAM_ANY );
+	}
+
+	/**
+	 * Collect adjacent areas to continue the search by calling 'IncludeInSearch' on each
+	 */
+	virtual void IterateAdjacentAreas( CNavArea *area, CNavArea *priorArea, float travelDistanceSoFar ) 
+	{
+		// search adjacent outgoing connections
+		for( int dir=0; dir<NUM_DIRECTIONS; ++dir )
+		{
+			int count = area->GetAdjacentCount( (NavDirType)dir );
+			for( int i=0; i<count; ++i )
+			{
+				CNavArea *adjArea = area->GetAdjacentArea( (NavDirType)dir, i );
+
+				if ( ShouldSearch( adjArea, area, travelDistanceSoFar ) )
+				{
+					IncludeInSearch( adjArea, area );
+				}
+			}
+		}
+	}
+
+	// Invoked after the search has completed
+	virtual void PostSearch( void ) { }
+
+	// consider 'area' in upcoming search steps
+	void IncludeInSearch( CNavArea *area, CNavArea *priorArea ) 
+	{
+		if ( area == NULL )
+			return;
+
+		if ( !area->IsMarked() )
+		{
+			area->Mark();
+			area->SetTotalCost( 0.0f );
+			area->SetParent( priorArea );
+
+			// compute approximate travel distance from start area of search
+			if ( priorArea )
+			{
+				float distAlong = priorArea->GetCostSoFar();
+				distAlong += ( area->GetCenter() - priorArea->GetCenter() ).Length();
+				area->SetCostSoFar( distAlong );
+			}
+			else
+			{
+				area->SetCostSoFar( 0.0f );
+			}
+
+			// adding an area to the open list also marks it
+			area->AddToOpenList();
+		}
+	}
+};
+
+
+/**
+ * Do a breadth-first search starting from 'startArea' and continuing outward based on
+ * adjacent areas that pass the given filter
+ */
+inline void SearchSurroundingAreas( CNavArea *startArea, ISearchSurroundingAreasFunctor &func, float travelDistanceLimit = -1.0f )
+{
+	if ( startArea )
+	{
+		CNavArea::MakeNewMarker();
+		CNavArea::ClearSearchLists();
+
+		startArea->AddToOpenList();
+		startArea->SetTotalCost( 0.0f );
+		startArea->SetCostSoFar( 0.0f );
+		startArea->SetParent( NULL );
+		startArea->Mark();
+
+		CUtlVector< CNavArea * > adjVector;
+
+		while( !CNavArea::IsOpenListEmpty() )
+		{
+			// get next area to check
+			CNavArea *area = CNavArea::PopOpenList();
+
+			if ( travelDistanceLimit > 0.0f && area->GetCostSoFar() > travelDistanceLimit )
+				continue;
+
+			if ( func( area, area->GetParent(), area->GetCostSoFar() ) )
+			{
+				func.IterateAdjacentAreas( area, area->GetParent(), area->GetCostSoFar() );
+			}
+			else
+			{
+				// search aborted
+				break;
+			}
+		}
+	}
+
+	func.PostSearch();
+}
+
+
+//--------------------------------------------------------------------------------------------------------------
+/**
+ * Starting from 'startArea', collect adjacent areas via a breadth-first search continuing outward until
+ * 'travelDistanceLimit' is reached.
+ * Areas in the collection will be "marked", returning true for IsMarked(). 
+ * Each area in the collection's GetCostSoFar() will be approximate travel distance from 'startArea'.
+ */
+inline void CollectSurroundingAreas( CUtlVector< CNavArea * > *nearbyAreaVector, CNavArea *startArea, float travelDistanceLimit = 1500.0f, float maxStepUpLimit = StepHeight, float maxDropDownLimit = 100.0f )
+{
+	nearbyAreaVector->RemoveAll();
+
+	if ( startArea )
+	{
+		CNavArea::MakeNewMarker();
+		CNavArea::ClearSearchLists();
+
+		startArea->AddToOpenList();
+		startArea->SetTotalCost( 0.0f );
+		startArea->SetCostSoFar( 0.0f );
+		startArea->SetParent( NULL );
+		startArea->Mark();
+
+		CUtlVector< CNavArea * > adjVector;
+
+		while( !CNavArea::IsOpenListEmpty() )
+		{
+			// get next area to check
+			CNavArea *area = CNavArea::PopOpenList();
+
+			if ( travelDistanceLimit > 0.0f && area->GetCostSoFar() > travelDistanceLimit )
+				continue;
+
+			if ( area->GetParent() )
+			{
+				float deltaZ = area->GetParent()->ComputeAdjacentConnectionHeightChange( area );
+
+				if ( deltaZ > maxStepUpLimit )
+					continue;
+
+				if ( deltaZ < -maxDropDownLimit )
+					continue;
+			}
+
+			nearbyAreaVector->AddToTail( area );
+
+			// mark here to ensure all marked areas are also valid areas that are in the collection
+			area->Mark();
+
+			// search adjacent outgoing connections
+			for( int dir=0; dir<NUM_DIRECTIONS; ++dir )
+			{
+				int count = area->GetAdjacentCount( (NavDirType)dir );
+				for( int i=0; i<count; ++i )
+				{
+					CNavArea *adjArea = area->GetAdjacentArea( (NavDirType)dir, i );
+
+					if ( adjArea->IsBlocked( TEAM_ANY ) )
+					{
+						continue;
+					}
+
+					if ( !adjArea->IsMarked() )
+					{
+						adjArea->SetTotalCost( 0.0f );
+						adjArea->SetParent( area );
+
+						// compute approximate travel distance from start area of search
+						float distAlong = area->GetCostSoFar();
+						distAlong += ( adjArea->GetCenter() - area->GetCenter() ).Length();
+						adjArea->SetCostSoFar( distAlong );
+						adjArea->AddToOpenList();
+					}
+				}
+			}
+		}
+	}
+}
+
+
+//--------------------------------------------------------------------------------------------------------------
+/**
+ * Functor that returns lowest cost for farthest away areas
+ * For use with FindMinimumCostArea()
+ */
+class FarAwayFunctor
+{
+public:
+	float operator() ( CNavArea *area, CNavArea *fromArea, const CNavLadder *ladder )
+	{
+		if (area == fromArea)
+			return 9999999.9f;
+
+		return 1.0f/(fromArea->GetCenter() - area->GetCenter()).Length();
+	}
+};
+
+/**
+ * Functor that returns lowest cost for areas farthest from given position
+ * For use with FindMinimumCostArea()
+ */
+class FarAwayFromPositionFunctor 
+{
+public:
+	FarAwayFromPositionFunctor( const Vector &pos ) : m_pos( pos )
+	{
+	}
+
+	float operator() ( CNavArea *area, CNavArea *fromArea, const CNavLadder *ladder )
+	{
+		return 1.0f/(m_pos - area->GetCenter()).Length();
+	}
+
+private:
+	const Vector &m_pos;
+};
+
+
+/**
+ * Pick a low-cost area of "decent" size
+ */
+template< typename CostFunctor >
+CNavArea *FindMinimumCostArea( CNavArea *startArea, CostFunctor &costFunc )
+{
+	const float minSize = 150.0f;
+
+	// collect N low-cost areas of a decent size
+	enum { NUM_CHEAP_AREAS = 32 };
+	struct 
+	{
+		CNavArea *area;
+		float cost;
+	}
+	cheapAreaSet[ NUM_CHEAP_AREAS ] = {};
+	int cheapAreaSetCount = 0;
+
+	FOR_EACH_VEC( TheNavAreas, iter )
+	{
+		CNavArea *area = TheNavAreas[iter];
+
+		// skip the small areas
+		if ( area->GetSizeX() < minSize || area->GetSizeY() < minSize)
+			continue;
+
+		// compute cost of this area
+
+		// HPE_FIX[pfreese]: changed this to only pass three parameters, in accord with the two functors above
+		float cost = costFunc( area, startArea, NULL );
+
+		if (cheapAreaSetCount < NUM_CHEAP_AREAS)
+		{
+			cheapAreaSet[ cheapAreaSetCount ].area = area;
+			cheapAreaSet[ cheapAreaSetCount++ ].cost = cost;
+		}
+		else
+		{
+			// replace most expensive cost if this is cheaper
+			int expensive = 0;
+			for( int i=1; i<NUM_CHEAP_AREAS; ++i )
+				if (cheapAreaSet[i].cost > cheapAreaSet[expensive].cost)
+					expensive = i;
+
+			if (cheapAreaSet[expensive].cost > cost)
+			{
+				cheapAreaSet[expensive].area = area;
+				cheapAreaSet[expensive].cost = cost;
+			}
+		}
+	}
+
+	if (cheapAreaSetCount)
+	{
+		// pick one of the areas at random
+		return cheapAreaSet[ RandomInt( 0, cheapAreaSetCount-1 ) ].area;
+	}
+	else
+	{
+		// degenerate case - no decent sized areas - pick a random area
+		int numAreas = TheNavAreas.Count();
+		int which = RandomInt( 0, numAreas-1 );
+
+		FOR_EACH_VEC( TheNavAreas, iter )
+		{
+			if (which-- == 0)
+				return TheNavAreas[iter];
+		}
+
+	}
+	return cheapAreaSet[ RandomInt( 0, cheapAreaSetCount-1 ) ].area;
+}
+
+
+//--------------------------------------------------------------------------------------------------------
+//
+// Given a vector of CNavAreas (or derived types), 'inVector', populate 'outVector' with a randomly shuffled set
+// of 'maxCount' areas that are at least 'minSeparation' travel distance apart from each other.
+//
+template< typename T >
+void SelectSeparatedShuffleSet( int maxCount, float minSeparation, const CUtlVector< T * > &inVector, CUtlVector< T * > *outVector )
+{
+	if ( !outVector )
+		return;
+
+	outVector->RemoveAll();
+
+	CUtlVector< T * > shuffledVector;
+
+	int i, j;
+
+	for( i=0; i<inVector.Count(); ++i )
+	{
+		shuffledVector.AddToTail( inVector[i] );
+	}
+
+	// randomly shuffle the order
+	int n = shuffledVector.Count();
+	while( n > 1 )
+	{
+		int k = RandomInt( 0, n-1 );
+		n--;
+
+		T *tmp = shuffledVector[n];
+		shuffledVector[n] = shuffledVector[k];
+		shuffledVector[k] = tmp;
+	}
+
+	// enforce minSeparation between shuffled areas
+	for( i=0; i<shuffledVector.Count(); ++i )
+	{
+		T *area = shuffledVector[i];
+
+		CUtlVector< CNavArea * > nearVector;
+		CollectSurroundingAreas( &nearVector, area, minSeparation, 2.0f * StepHeight, 2.0f * StepHeight );
+
+		for( j=0; j<i; ++j )
+		{
+			if ( nearVector.HasElement( (CNavArea *)shuffledVector[j] ) )
+			{
+				// this area is too near an area earlier in the vector
+				break;
+			}
+		}
+
+		if ( j == i )
+		{
+			// separated from all prior areas
+			outVector->AddToTail( area );
+
+			if ( outVector->Count() >= maxCount )
+				return;
+		}
+	}
+}
+
+
+#endif // _NAV_PATHFIND_H_