Core: Combat/threat system rewrite (PR #19930)

- PvE combat is now always mutual. UNIT_FLAG_IN_COMBAT is backed by actual references to the units we're in combat with.
- PvP combat is now also tracked, and almost always mutual; spells like Vanish and Feign Death can break this rule. That means we can easily determine a list of players we're fighting.
- By extension, IsInCombatWith now has sensible behavior when invoked on nonplayers.
- Threat and combat systems are no longer the same.
  - They still have an enforced relationship (threat implies combat - clearing combat clears threat)...
  - ...but we can have combat without threat. A creature (with threat list) isn't considered to be engaged until it has an entry on its threat list...
  - ...which means we can now faithfully replicate retail engage behavior. Combat on projectile launch - engagement start on projectile impact. Yay for progress!
- AI method refactor, as already ported in 6113b9d - `JustEngagedWith`, `JustEnteredCombat` and `JustExitedCombat`.
- Vehicle threat is now properly pooled on the main vehicle body (fixes #16542).
- Various edge case bug fixes for threat redirects (Misdirection "cancelling" Vigilance and similar).
- Target re-selection is now significantly faster.
- Fixed a ton of other smaller edge case bugs, probably.

Closes #7951 and #19998.

1 files changed, 5 insertions, 16 deletions

diff --git a/src/server/game/Maps/Map.cpp b/src/server/game/Maps/Map.cpp
index 1d759054745..8c1cf06a4f5 100644
--- a/src/server/game/Maps/Map.cpp
+++ b/src/server/game/Maps/Map.cpp
@@ -792,21 +792,10 @@ void Map::Update(uint32 t_diff)
         // Handle updates for creatures in combat with player and are more than 60 yards away
         if (player->IsInCombat())
         {
-            std::vector<Creature*> updateList;
-            HostileReference* ref = player->getHostileRefManager().getFirst();
-
-            while (ref)
-            {
-                if (Unit* unit = ref->GetSource()->GetOwner())
-                    if (unit->ToCreature() && unit->GetMapId() == player->GetMapId() && !unit->IsWithinDistInMap(player, GetVisibilityRange(), false))
-                        updateList.push_back(unit->ToCreature());
-
-                ref = ref->next();
-            }
-
-            // Process deferred update list for player
-            for (Creature* c : updateList)
-                VisitNearbyCellsOf(c, grid_object_update, world_object_update);
+            for (auto const& pair : player->GetCombatManager().GetPvECombatRefs())
+                if (Creature* unit = pair.second->GetOther(player)->ToCreature())
+                    if (unit->GetMapId() == player->GetMapId() && !unit->IsWithinDistInMap(player, GetVisibilityRange(), false))
+                        VisitNearbyCellsOf(unit, grid_object_update, world_object_update);
         }
     }
 
@@ -947,7 +936,7 @@ void Map::RemovePlayerFromMap(Player* player, bool remove)
     player->UpdateZone(MAP_INVALID_ZONE, 0);
     sScriptMgr->OnPlayerLeaveMap(this, player);
 
-    player->getHostileRefManager().deleteReferences(); // multithreading crashfix
+    player->CombatStop();
 
     bool const inWorld = player->IsInWorld();
     player->RemoveFromWorld();