AI grenade throw hints

sp/src/game/server/ai_hint.cpp

@@ -1325,7 +1325,7 @@ bool CAI_Hint::HintMatchesCriteria( CAI_BaseNPC *pNPC, const CHintCriteria &hint
 
 		if ( distance > nRadius * nRadius )
 		{
-			REPORTFAILURE( "NPC is not within the node's radius." );
+			REPORTFAILURE( "Not within the node's radius." );
 			return false;
 		}
 	}
@@ -1794,6 +1794,11 @@ hinttypedescs_t g_pszHintDescriptions[] =
 	{	HINT_HL1_WORLD_ALIEN_BLOOD, "HL1: World: Alien Blood"	},
 
 	{	HINT_CSTRIKE_HOSTAGE_ESCAPE, "CS Port: Hostage Escape"	},
+
+#ifdef MAPBASE
+	{	HINT_TACTICAL_COVER_CUSTOM, "Mapbase: Custom Cover"	},
+	{	HINT_TACTICAL_GRENADE_THROW, "Mapbase: Grenade Throw Hint"	},
+#endif
 };
 
 //-----------------------------------------------------------------------------

sp/src/game/server/ai_hint.h

@@ -118,6 +118,7 @@ enum Hint_e
 	// (these start at a high number to avoid potential conflicts with mod hints)
 
 	HINT_TACTICAL_COVER_CUSTOM = 10000,	// Cover node with a custom hint activity (NPCs can take cover and reload here while playing said activity)
+	HINT_TACTICAL_GRENADE_THROW,		// Pre-determined position for NPCs to throw grenades at when their target in combat is near it
 #endif
 };
 const char *GetHintTypeDescription( Hint_e iHintType );

sp/src/game/server/mapbase/ai_grenade.h

@@ -138,6 +138,8 @@ public:
 
 	void			ClearAttackConditions( void );
 
+	bool			FValidateHintType( CAI_Hint *pHint );
+
 	Vector			GetAltFireTarget() { return m_vecAltFireTarget; }
 	virtual bool	CanAltFireEnemy( bool bUseFreeKnowledge );
 	void			DelayAltFireAttack( float flDelay );
@@ -558,6 +560,29 @@ bool CAI_GrenadeUser<BASE_NPC>::CanThrowGrenade( const Vector &vecTarget )
 		}
 	}
 
+	CHintCriteria hintCriteria;
+	hintCriteria.SetHintType( HINT_TACTICAL_GRENADE_THROW );
+	hintCriteria.SetFlag( bits_HINT_NPC_IN_NODE_FOV );
+	hintCriteria.SetGroup( this->GetHintGroup() );
+	hintCriteria.AddIncludePosition( this->GetAbsOrigin(), 1024 );
+
+	if (this->m_debugOverlays & OVERLAY_NPC_SELECTED_BIT)
+		hintCriteria.SetFlag( bits_HINT_NODE_REPORT_FAILURES );
+	
+	// If there's a grenade throw hint nearby, try using it
+	CAI_Hint *pHint = CAI_HintManager::FindHint( this, vecTarget, hintCriteria );
+	if ( pHint )
+	{
+		if ( CheckCanThrowGrenade( pHint->GetAbsOrigin() ) )
+		{
+			return true;
+		}
+		else
+		{
+			DevMsg( this, "Unable to throw grenade at hint %s\n", pHint->GetDebugName() );
+		}
+	}
+
 	return CheckCanThrowGrenade( vecTarget );
 }
 
@@ -636,6 +661,18 @@ void CAI_GrenadeUser<BASE_NPC>::ClearAttackConditions()
 	}
 }
 
+//-----------------------------------------------------------------------------
+// Purpose: 
+//-----------------------------------------------------------------------------
+template <class BASE_NPC>
+bool CAI_GrenadeUser<BASE_NPC>::FValidateHintType( CAI_Hint *pHint )
+{
+	if ( pHint->HintType() == HINT_TACTICAL_GRENADE_THROW )
+		return true;
+
+	return BaseClass::FValidateHintType( pHint );
+}
+
 //-----------------------------------------------------------------------------
 // Purpose: Drops grenades and alt-fire items on death. Based on code from npc_combines.cpp and npc_combine.cpp
 //-----------------------------------------------------------------------------