[Performance] Reworked how client to NPC aggro checks are made

- Before when reverse aggro checks were done (client to NPC), checks would happen every 750 millseconds where a client would
		check an entire entity list with distance calcs and other checks for aggro, with many clients in a zone and many NPC's this would
		add a lot of unecessary overhead. A temporary adjustment on 3/25 was made and upped the check to 6 seconds.
	- Now, there is a new methodology to scanning. The client will build a cache list of NPC's within close range as defined in new rule:
		RULE_INT(Range, ClientNPCScan, 300) and will also get any NPC that has an aggro range beyond that defined range to use in
		the frequent checks for aggro, the result is far less overhead
	- Client scanning changes when moving versus not moving, the client will scan aggro every 500 milliseconds while moving, and
		3000 millseconds aggro check when not moving, with a 6000ms re-fetch for close NPC's
	- A demo of these changes can be found here:
		https://youtu.be/aGroiwLSTVU

changelog.txt

@@ -1,8 +1,21 @@
 EQEMu Changelog (Started on Sept 24, 2003 15:50)
 -------------------------------------------------------
+== 03/27/2017 ==
+Akkadius: [Performance] Reworked how client to NPC aggro checks are made
+	- Before when reverse aggro checks were done (client to NPC), checks would happen every 750 millseconds where a client would
+		check an entire entity list with distance calcs and other checks for aggro, with many clients in a zone and many NPC's this would
+		add a lot of unecessary overhead. A temporary adjustment on 3/25 was made and upped the check to 6 seconds.
+	- Now, there is a new methodology to scanning. The client will build a cache list of NPC's within close range as defined in new rule:
+		RULE_INT(Range, ClientNPCScan, 300) and will also get any NPC that has an aggro range beyond that defined range to use in 
+		the frequent checks for aggro, the result is far less overhead
+	- Client scanning changes when moving versus not moving, the client will scan aggro every 500 milliseconds while moving, and
+		3000 millseconds aggro check when not moving, with a 6000ms re-fetch for close NPC's
+	- A demo of these changes can be found here:
+		https://youtu.be/aGroiwLSTVU
+
 == 03/25/2017 ==
-Akkadius: Reduced CPU footprint in non-combat zones doing constant checks for combat related activities
-Akkadius: Reduced CPU footprint in cases where a client is checking for aggro excessively every 750 millseconds. This has 
+Akkadius: [Performance] Reduced CPU footprint in non-combat zones doing constant checks for combat related activities
+Akkadius: [Performance] Reduced CPU footprint in cases where a client is checking for aggro excessively every 750 millseconds. This has 
 	been adjusted to 6 seconds per new rule RULE_INT(Aggro, ClientAggroCheckInterval)
 	- When zones have many players, with many NPC's, this adds up quickly
 

common/ruletypes.h

@@ -559,6 +559,7 @@ RULE_INT(Range, SpellMessages, 75)
 RULE_INT(Range, SongMessages, 75)
 RULE_INT(Range, MobPositionUpdates, 600)
 RULE_INT(Range, CriticalDamage, 80)
+RULE_INT(Range, ClientNPCScan, 300)
 RULE_CATEGORY_END()
 
 

zone/client.cpp

@@ -135,7 +135,7 @@ Client::Client(EQStreamInterface* ieqs)
 	forget_timer(0),
 	autosave_timer(RuleI(Character, AutosaveIntervalS) * 1000),
 #ifdef REVERSE_AGGRO
-	scanarea_timer(RuleI(Aggro, ClientAggroCheckInterval) * 1000),
+	client_scan_npc_aggro_timer(RuleI(Aggro, ClientAggroCheckInterval) * 1000),
 #endif
 	tribute_timer(Tribute_duration),
 	proximity_timer(ClientProximity_interval),
@@ -160,7 +160,8 @@ Client::Client(EQStreamInterface* ieqs)
 	m_AutoAttackPosition(0.0f, 0.0f, 0.0f, 0.0f),
 	m_AutoAttackTargetLocation(0.0f, 0.0f, 0.0f),
 	last_region_type(RegionTypeUnsupported),
-	m_dirtyautohaters(false)
+	m_dirtyautohaters(false),
+	npc_close_scan_timer(6000)
 {
 	for(int cf=0; cf < _FilterCount; cf++)
 		ClientFilters[cf] = FilterShow;
@@ -358,6 +359,8 @@ Client::~Client() {
 		m_tradeskill_object = nullptr;
 	}
 
+	close_npcs.clear();
+
 	if(IsDueling() && GetDuelTarget() != 0) {
 		Entity* entity = entity_list.GetID(GetDuelTarget());
 		if(entity != nullptr && entity->IsClient()) {

zone/client.h

@@ -221,6 +221,9 @@ public:
 	Client(EQStreamInterface * ieqs);
 	~Client();
 
+	std::unordered_map<NPC *, float> close_npcs;
+	bool is_client_moving;
+
 	//abstract virtual function implementations required by base abstract class
 	virtual bool Death(Mob* killerMob, int32 damage, uint16 spell_id, EQEmu::skills::SkillType attack_skill);
 	virtual void Damage(Mob* from, int32 damage, uint16 spell_id, EQEmu::skills::SkillType attack_skill, bool avoidable = true, int8 buffslot = -1, bool iBuffTic = false, eSpecialAttacks special = eSpecialAttacks::None);
@@ -1458,7 +1461,7 @@ private:
 	Timer forget_timer; // our 2 min everybody forgets you timer
 	Timer autosave_timer;
 #ifdef REVERSE_AGGRO
-	Timer scanarea_timer;
+	Timer client_scan_npc_aggro_timer;
 #endif
 	Timer tribute_timer;
 
@@ -1477,6 +1480,7 @@ private:
 	Timer helm_toggle_timer;
 	Timer light_update_timer;
 	Timer aggro_meter_timer;
+	Timer npc_close_scan_timer;
 
     glm::vec3 m_Proximity;
 

zone/client_packet.cpp

@@ -4580,6 +4580,34 @@ void Client::Handle_OP_ClientUpdate(const EQApplicationPacket *app)
 		rewind_timer.Start(30000, true);
 	}
 
+
+	/* Handle client aggro scanning timers NPCs */
+	is_client_moving = (ppu->y_pos == m_Position.y && ppu->x_pos == m_Position.x) ? false : true;
+
+	if (is_client_moving) {
+		Log.Out(Logs::Detail, Logs::Normal, "ClientUpdate: Client is moving - scan timer is: %u", client_scan_npc_aggro_timer.GetDuration());
+		if (client_scan_npc_aggro_timer.GetDuration() > 1000) {
+
+			npc_close_scan_timer.Disable();
+			npc_close_scan_timer.Start(500);
+
+			client_scan_npc_aggro_timer.Disable();
+			client_scan_npc_aggro_timer.Start(500);
+
+		}
+	}
+	else {
+		Log.Out(Logs::Detail, Logs::Normal, "ClientUpdate: Client is NOT moving - scan timer is: %u", client_scan_npc_aggro_timer.GetDuration());
+		if (client_scan_npc_aggro_timer.GetDuration() < 1000) {
+
+			npc_close_scan_timer.Disable();
+			npc_close_scan_timer.Start(6000);
+
+			client_scan_npc_aggro_timer.Disable();
+			client_scan_npc_aggro_timer.Start(3000);
+		}
+	}
+
 	// Outgoing client packet
 	float tmpheading = EQ19toFloat(ppu->heading);
 	/* The clients send an update at best every 1.3 seconds

zone/client_process.cpp

@@ -161,34 +161,29 @@ bool Client::Process() {
 			return(false);
 		}
 
-		if(charm_update_timer.Check())
-		{
+		if (charm_update_timer.Check()) {
 			CalcItemScale();
 		}
 
 		if (TaskPeriodic_Timer.Check() && taskstate)
 			taskstate->TaskPeriodicChecks(this);
 
-		if(linkdead_timer.Check())
-		{
+		if (linkdead_timer.Check()) {
 			LeaveGroup();
 			Save();
-			if (GetMerc())
-			{
+			if (GetMerc()) {
 				GetMerc()->Save();
 				GetMerc()->Depop();
 			}
 
 			Raid *myraid = entity_list.GetRaidByClient(this);
-			if (myraid)
-			{
+			if (myraid) {
 				myraid->MemberZoned(this);
 			}
 			return false; //delete client
 		}
 
-		if (camp_timer.Check())
-		{
+		if (camp_timer.Check()) {
 			LeaveGroup();
 			Save();
 			if (GetMerc())
@@ -202,8 +197,7 @@ bool Client::Process() {
 		if (IsStunned() && stunned_timer.Check())
 			Mob::UnStun();
 
-		if(!m_CheatDetectMoved)
-		{
+		if (!m_CheatDetectMoved) {
 			m_TimeSinceLastPositionCheck = Timer::GetCurrentTime();
 		}
 
@@ -213,26 +207,26 @@ bool Client::Process() {
 			Mob *song_target = nullptr;
 			if (bardsong_target_id == GetID()) {
 				song_target = this;
-			} else {
+			}
+			else {
 				song_target = entity_list.GetMob(bardsong_target_id);
 			}
 
 			if (song_target == nullptr) {
 				InterruptSpell(SONG_ENDS_ABRUPTLY, 0x121, bardsong);
-			} else {
+			}
+			else {
 				if (!ApplyNextBardPulse(bardsong, song_target, bardsong_slot))
 					InterruptSpell(SONG_ENDS_ABRUPTLY, 0x121, bardsong);
 				//SpellFinished(bardsong, bardsong_target, bardsong_slot, spells[bardsong].mana);
 			}
 		}
 
-		if(GetMerc())
-		{
+		if (GetMerc()) {
 			UpdateMercTimer();
 		}
 
-		if(GetMercInfo().MercTemplateID != 0 && GetMercInfo().IsSuspended)
-		{
+		if (GetMercInfo().MercTemplateID != 0 && GetMercInfo().IsSuspended) {
 			CheckMercSuspendTimer();
 		}
 
@@ -244,19 +238,15 @@ bool Client::Process() {
 			BindWound(bindwound_target, false);
 		}
 
-		if(KarmaUpdateTimer)
-		{
-			if(KarmaUpdateTimer->Check(false))
-			{
+		if (KarmaUpdateTimer) {
+			if (KarmaUpdateTimer->Check(false)) {
 				KarmaUpdateTimer->Start(RuleI(Chat, KarmaUpdateIntervalMS));
 				database.UpdateKarma(AccountID(), ++TotalKarma);
 			}
 		}
 
-		if(qGlobals)
-		{
-			if(qglobal_purge_timer.Check())
-			{
+		if (qGlobals) {
+			if (qglobal_purge_timer.Check()) {
 				qGlobals->PurgeExpiredGlobals();
 			}
 		}
@@ -269,6 +259,28 @@ bool Client::Process() {
 			}
 		}
 
+
+		/* Build a close range list of NPC's  */
+		if (npc_close_scan_timer.Check()) {
+
+			close_npcs.clear();
+
+			std::list<NPC*> npc_list;
+			entity_list.GetNPCList(npc_list);
+
+			float scan_range = RuleI(Range, ClientNPCScan);
+			for (auto itr = npc_list.begin(); itr != npc_list.end(); ++itr) {
+				NPC* npc = *itr;
+				float distance = DistanceNoZ(m_Position, npc->GetPosition());
+				if(distance <= scan_range) {
+					close_npcs.insert(std::pair<NPC *, float>(npc, distance));
+				}
+				else if (npc->GetAggroRange() > scan_range) {
+					close_npcs.insert(std::pair<NPC *, float>(npc, distance));
+				}
+			}
+		}
+
 		bool may_use_attacks = false;
 		/*
 			Things which prevent us from attacking:
@@ -616,8 +628,17 @@ bool Client::Process() {
 	//At this point, we are still connected, everything important has taken
 	//place, now check to see if anybody wants to aggro us.
 	// only if client is not feigned
-	if(zone->CanDoCombat() && ret && !GetFeigned() && scanarea_timer.Check()) {
-		entity_list.CheckClientAggro(this);
+	if (zone->CanDoCombat() && ret && !GetFeigned() && client_scan_npc_aggro_timer.Check()) {
+		int npc_scan_count = 0;
+		for (auto it = close_npcs.begin(); it != close_npcs.end(); ++it) {
+			NPC *npc = it->first;
+
+			if (npc->CheckWillAggro(this) && !npc->CheckAggro(this)) {
+				npc->AddToHateList(this, 25);
+			}
+			npc_scan_count++;
+		}
+		Log.Out(Logs::General, Logs::Aggro, "Checking Reverse Aggro (client->npc) scanned_npcs (%i)", npc_scan_count);
 	}
 #endif
 

zone/entity.cpp

@@ -2288,10 +2288,15 @@ bool EntityList::RemoveNPC(uint16 delete_id)
 {
 	auto it = npc_list.find(delete_id);
 	if (it != npc_list.end()) {
+		NPC *npc = it->second;
 		// make sure its proximity is removed
 		RemoveProximity(delete_id);
+		// remove from client close lists
+		RemoveNPCFromClientCloseLists(npc);
 		// remove from the list
 		npc_list.erase(it);
+		
+
 		// remove from limit list if needed
 		if (npc_limit_list.count(delete_id))
 			npc_limit_list.erase(delete_id);
@@ -2300,6 +2305,16 @@ bool EntityList::RemoveNPC(uint16 delete_id)
 	return false;
 }
 
+bool EntityList::RemoveNPCFromClientCloseLists(NPC *npc)
+{
+	auto it = client_list.begin();
+	while (it != client_list.end()) {
+		it->second->close_npcs.erase(npc);
+		++it;
+	}
+	return false;
+}
+
 bool EntityList::RemoveMerc(uint16 delete_id)
 {
 	auto it = merc_list.find(delete_id);

zone/entity.h

@@ -279,6 +279,7 @@ public:
 	bool	RemoveTrap(uint16 delete_id);
 	bool	RemoveObject(uint16 delete_id);
 	bool	RemoveProximity(uint16 delete_npc_id);
+	bool	RemoveNPCFromClientCloseLists(NPC *npc);
 	void	RemoveAllMobs();
 	void	RemoveAllClients();
 	void	RemoveAllNPCs();