Bots skip goals no route reaches

src/game/server/neo/bot/behavior/neo_bot_jgr_juggernaut.cpp

@@ -2,7 +2,6 @@
 #include "neo_player.h"
 #include "neo_gamerules.h"
 #include "bot/neo_bot.h"
-#include "bot/neo_bot_path_compute.h"
 #include "bot/behavior/neo_bot_jgr_juggernaut.h"
 #include "bot/behavior/neo_bot_retreat_to_cover.h"
 #include "weapon_balc.h"
@@ -70,7 +69,7 @@ void CNEOBotJgrJuggernaut::RecomputeSeekPath( CNEOBot *me )
 			m_vGoalPos = pTargetSpawn->GetAbsOrigin();
 			m_bGoingToTargetEntity = false;
 
-			if (CNEOBotPathCompute(me, m_path, m_vGoalPos, DEFAULT_ROUTE) && m_path.IsValid() && m_path.GetResult() == Path::COMPLETE_PATH)
+			if (TryPathToRoamGoal(me, m_vGoalPos))
 			{
 				return;
 			}

src/game/server/neo/bot/behavior/neo_bot_retreat_to_cover.cpp

@@ -354,6 +354,20 @@ ActionResult< CNEOBot >	CNEOBotRetreatToCover::Update( CNEOBot *me, float interv
 		if ( !m_path.IsValid() )
 		{
 			CNEOBotPathCompute( me, m_path, m_coverArea->GetCenter(), RETREAT_ROUTE );
+
+			// Cover is chosen where the retreat starts; after a drop off a ledge no route
+			// may reach it any more, so choose again from here
+			if ( !CNEOBotPathReachesGoal( m_path ) )
+			{
+				CNavArea *pUnreachableArea = m_coverArea;
+				m_coverArea = FindCoverArea( me );
+				if ( m_coverArea == NULL || m_coverArea == pUnreachableArea )
+				{
+					return Done( "My cover is out of reach, and there is no other cover available!" );
+				}
+
+				CNEOBotPathCompute( me, m_path, m_coverArea->GetCenter(), RETREAT_ROUTE );
+			}
 		}
 
 		m_path.Update( me );

src/game/server/neo/bot/behavior/neo_bot_seek_and_destroy.cpp

@@ -106,8 +106,7 @@ bool CNEOBotSeekAndDestroy::TryPathToCombatSound( CNEOBot *me )
 		m_combatSoundCommitTimer.Start( sv_neo_bot_seek_and_destroy_combat_sound_commit_time.GetFloat() );
 	}
 
-	if ( CNEOBotPathCompute( me, m_path, m_vCombatSoundSpot, DEFAULT_ROUTE )
-			&& m_path.IsValid() && m_path.GetResult() == Path::COMPLETE_PATH )
+	if ( TryPathToRoamGoal( me, m_vCombatSoundSpot ) )
 	{
 		m_vGoalPos = m_vCombatSoundSpot;
 		m_bGoingToTargetEntity = false;
@@ -128,6 +127,15 @@ bool CNEOBotSeekAndDestroy::TryPathToCombatSound( CNEOBot *me )
 }
 
 
+//---------------------------------------------------------------------------------------------
+// Roam goals are picked at random, so skip one that no route reaches instead of walking at it. A refused
+// attempt stays in m_path: the wander loop's last resort keeps it.
+bool CNEOBotSeekAndDestroy::TryPathToRoamGoal( CNEOBot *me, const Vector &vGoal )
+{
+	return CNEOBotPathCompute( me, m_path, vGoal, DEFAULT_ROUTE ) && CNEOBotPathReachesGoal( m_path );
+}
+
+
 //---------------------------------------------------------------------------------------------
 CNEOBotSeekAndDestroy::CNEOBotSeekAndDestroy( float duration )
 {
@@ -592,7 +600,7 @@ void CNEOBotSeekAndDestroy::RecomputeSeekPath( CNEOBot *me )
 				m_hTargetEntity = pSpawns[RandomInt( 0, pSpawns.Size() - 1 )];
 				m_bGoingToTargetEntity = true;
 				m_vGoalPos = m_hTargetEntity->WorldSpaceCenter();
-				if ( CNEOBotPathCompute( me, m_path, m_vGoalPos, DEFAULT_ROUTE ) && m_path.IsValid() && m_path.GetResult() == Path::COMPLETE_PATH )
+				if ( TryPathToRoamGoal( me, m_vGoalPos ) )
 					return;
 			}
 		}
@@ -604,11 +612,12 @@ void CNEOBotSeekAndDestroy::RecomputeSeekPath( CNEOBot *me )
 
 		Vector vWanderPoint = TheNavAreas[RandomInt( 0, TheNavAreas.Size() - 1 )]->GetCenter();
 		m_vGoalPos = vWanderPoint;
-		if ( CNEOBotPathCompute( me, m_path, vWanderPoint, DEFAULT_ROUTE ) )
+		if ( TryPathToRoamGoal( me, vWanderPoint ) )
 			return;
 	}
 
-	m_path.Invalidate();
+	// No wander point has a route either (a pocket, or hazards all round): keep the last one's partial or
+	// straight-line path rather than stand still
 }
 
 

src/game/server/neo/bot/behavior/neo_bot_seek_and_destroy.h

@@ -36,6 +36,7 @@ class CNEOBotSeekAndDestroy : public Action< CNEOBot >
 	virtual void RecomputeSeekPath( CNEOBot *me );
 
 	bool TryPathToCombatSound( CNEOBot *me );
+	bool TryPathToRoamGoal( CNEOBot *me, const Vector &vGoal );
 	virtual bool IsSeekGoalAnObjective() const	{ return false; }
 
 	PathFollower m_path;

src/game/server/neo/bot/neo_bot_path_compute.cpp

@@ -69,6 +69,24 @@ bool CNEOBotPathCompute(CNEOBot* bot, PathFollower& path, const Vector& goal, Ro
 	return false;
 }
 
+// When no route reaches the goal and the search got no nearer to it than the bot's own area,
+// Path::Compute falls back to a straight line labeled COMPLETE_PATH: two segments in two areas
+bool CNEOBotPathReachesGoal(const PathFollower& path)
+{
+	if (!path.IsValid() || path.GetResult() != Path::COMPLETE_PATH)
+	{
+		return false;
+	}
+
+	const Path::Segment* pFirst = path.FirstSegment();
+	const Path::Segment* pLast = path.LastSegment();
+
+	// A goal inside the bot's own area also gives a two-segment path,
+	// so where the areas nearest the bot and the goal differ (stacked or overlapping areas) it reads as the fallback
+	const bool bStraightLineFallback = (path.NextSegment(pFirst) == pLast) && (pFirst->area != pLast->area);
+	return !bStraightLineFallback;
+}
+
 bool CNEOBotPathUpdateChase(CNEOBot* bot, ChasePath& path, CBaseEntity* subject, RouteType route, Vector* pPredictedSubjectPos)
 {
 	CNEOBotPathCost cost_with_reservations(bot, route);

src/game/server/neo/bot/neo_bot_path_compute.h

@@ -18,6 +18,10 @@ bool CNEOBotPathCompute
 	bool requireGoalArea = false
 );
 
+// True if the path reaches its goal: complete, and not the straight-line fallback
+// Path::Compute builds when no route reaches the goal
+bool CNEOBotPathReachesGoal(const PathFollower& path);
+
 bool CNEOBotPathUpdateChase
 (
 	CNEOBot *bot,