Core/Units: Updated armor damage reduction calculation

Merge #17069

8 files changed, 27 insertions, 20 deletions

diff --git a/src/server/game/DataStores/DBCStores.cpp b/src/server/game/DataStores/DBCStores.cpp
index 921db480853..0f16acb3df3 100644
--- a/src/server/game/DataStores/DBCStores.cpp
+++ b/src/server/game/DataStores/DBCStores.cpp
@@ -158,6 +158,7 @@ DBCStorage<WorldMapAreaEntry>               sWorldMapAreaStore(WorldMapAreafmt);
 DBCStorage<WorldMapTransformsEntry>         sWorldMapTransformsStore(WorldMapTransformsfmt);
 DBCStorage<WorldSafeLocsEntry>              sWorldSafeLocsStore(WorldSafeLocsfmt);
 
+GameTable<GtArmorMitigationByLvlEntry>      sGtArmorMitigationByLvlStore(GtArmorMitigationByLvlfmt);
 GameTable<GtBarberShopCostBaseEntry>        sGtBarberShopCostBaseStore(GtBarberShopCostBasefmt);
 GameTable<GtChanceToMeleeCritBaseEntry>     sGtChanceToMeleeCritBaseStore(GtChanceToMeleeCritBasefmt);
 GameTable<GtChanceToMeleeCritEntry>         sGtChanceToMeleeCritStore(GtChanceToMeleeCritfmt);
@@ -507,6 +508,7 @@ void LoadGameTables(const std::string& dataPath, uint32 defaultLocale)
 
 #define LOAD_GT(tableName, store, file) LoadGameTable(bad_dbc_files, tableName, store, dbcPath, file)
 
+    LOAD_GT("ArmorMitigationByLvl", sGtArmorMitigationByLvlStore, "gtArmorMitigationByLvl.dbc");                // 21463
     LOAD_GT("BarberShopCostBase", sGtBarberShopCostBaseStore, "gtBarberShopCostBase.dbc");                      // 20444
     LOAD_GT("CombatRatings", sGtCombatRatingsStore, "gtCombatRatings.dbc");                                     // 20444
     LOAD_GT("ChanceToMeleeCritBase", sGtChanceToMeleeCritBaseStore, "gtChanceToMeleeCritBase.dbc");             // 20444
diff --git a/src/server/game/DataStores/DBCStores.h b/src/server/game/DataStores/DBCStores.h
index 7c7647dd4d9..0d162cec961 100644
--- a/src/server/game/DataStores/DBCStores.h
+++ b/src/server/game/DataStores/DBCStores.h
@@ -207,6 +207,7 @@ TC_GAME_API extern DBCStorage<VehicleSeatEntry>                 sVehicleSeatStor
 TC_GAME_API extern DBCStorage<WMOAreaTableEntry>                sWMOAreaTableStore;
 TC_GAME_API extern DBCStorage<WorldSafeLocsEntry>               sWorldSafeLocsStore;
 
+TC_GAME_API extern GameTable<GtArmorMitigationByLvlEntry>       sGtArmorMitigationByLvlStore;
 TC_GAME_API extern GameTable<GtBarberShopCostBaseEntry>         sGtBarberShopCostBaseStore;
 TC_GAME_API extern GameTable<GtChanceToMeleeCritBaseEntry>      sGtChanceToMeleeCritBaseStore;
 TC_GAME_API extern GameTable<GtChanceToMeleeCritEntry>          sGtChanceToMeleeCritStore;
diff --git a/src/server/game/DataStores/DBCStructure.h b/src/server/game/DataStores/DBCStructure.h
index 4f5f162b33e..5eed5ca0b6d 100644
--- a/src/server/game/DataStores/DBCStructure.h
+++ b/src/server/game/DataStores/DBCStructure.h
@@ -515,6 +515,12 @@ struct GlyphPropertiesEntry
     //uint32    GlyphExclusiveCategoryID;                   // 4
 };
 
+struct GtArmorMitigationByLvlEntry
+{
+    //uint32 level;
+    float   KFactor;
+};
+
 struct GtBarberShopCostBaseEntry
 {
     //uint32 level;
diff --git a/src/server/game/DataStores/DBCfmt.h b/src/server/game/DataStores/DBCfmt.h
index 16f5383c343..171eec94266 100644
--- a/src/server/game/DataStores/DBCfmt.h
+++ b/src/server/game/DataStores/DBCfmt.h
@@ -49,6 +49,7 @@ char const FactionTemplatefmt[] = "niiiiiiiiiiiii";
 char const GameObjectDisplayInfofmt[] = "nixxxxxxxxxxffffffxxx";
 char const GemPropertiesfmt[] = "nixxii";
 char const GlyphPropertiesfmt[] = "niiix";
+char const GtArmorMitigationByLvlfmt[] = "xf";
 char const GtBarberShopCostBasefmt[] = "xf";
 char const GtCombatRatingsfmt[] = "xf";
 char const GtOCTHpPerStaminafmt[] = "df";
diff --git a/src/server/game/Entities/Unit/Unit.cpp b/src/server/game/Entities/Unit/Unit.cpp
index 46fce40bc0d..c77e3785924 100644
--- a/src/server/game/Entities/Unit/Unit.cpp
+++ b/src/server/game/Entities/Unit/Unit.cpp
@@ -1001,7 +1001,7 @@ void Unit::CalculateSpellDamageTaken(SpellNonMeleeDamage* damageInfo, int32 dama
     if (!spellInfo->HasAttribute(SPELL_ATTR4_FIXED_DAMAGE))
     {
         if (IsDamageReducedByArmor(damageSchoolMask, spellInfo))
-            damage = CalcArmorReducedDamage(victim, damage, spellInfo, attackType);
+            damage = CalcArmorReducedDamage(damageInfo->attacker, victim, damage, spellInfo, attackType);
 
         bool blocked = false;
         // Per-school calc
@@ -1182,7 +1182,7 @@ void Unit::CalculateMeleeDamage(Unit* victim, uint32 damage, CalcDamageInfo* dam
     // Calculate armor reduction
     if (IsDamageReducedByArmor((SpellSchoolMask)(damageInfo->damageSchoolMask)))
     {
-        damageInfo->damage = CalcArmorReducedDamage(damageInfo->target, damage, NULL, damageInfo->attackType);
+        damageInfo->damage = CalcArmorReducedDamage(damageInfo->attacker, damageInfo->target, damage, NULL, damageInfo->attackType);
         damageInfo->cleanDamage += damage - damageInfo->damage;
     }
     else
@@ -1473,7 +1473,7 @@ bool Unit::IsDamageReducedByArmor(SpellSchoolMask schoolMask, SpellInfo const* s
     return true;
 }
 
-uint32 Unit::CalcArmorReducedDamage(Unit* victim, const uint32 damage, SpellInfo const* spellInfo, WeaponAttackType /*attackType*/)
+uint32 Unit::CalcArmorReducedDamage(Unit* attacker, Unit* victim, const uint32 damage, SpellInfo const* spellInfo, WeaponAttackType /*attackType*/)
 {
     float armor = float(victim->GetArmor());
 
@@ -1516,22 +1516,19 @@ uint32 Unit::CalcArmorReducedDamage(Unit* victim, const uint32 damage, SpellInfo
         armor -= std::min(armorPen, maxArmorPen);
     }
 
-    if (armor < 0.0f)
-        armor = 0.0f;
+    if (G3D::fuzzyLe(armor, 0.0f))
+        return damage;
 
-    float levelModifier = getLevel();
-    if (levelModifier > 59)
-        levelModifier = levelModifier + 4.5f * (levelModifier - 59);
+    uint8 attackerLevel = attacker->getLevel();
+    if (attackerLevel > sGtArmorMitigationByLvlStore.GetTableRowCount())
+        attackerLevel = sGtArmorMitigationByLvlStore.GetTableRowCount();
 
-    float tmpvalue = 0.1f * armor / (8.5f * levelModifier + 40);
-    tmpvalue = tmpvalue / (1.0f + tmpvalue);
+    GtArmorMitigationByLvlEntry const* ambl = sGtArmorMitigationByLvlStore.EvaluateTable(attackerLevel - 1, 0);
+    if (!ambl)
+        return damage;
 
-    if (tmpvalue < 0.0f)
-        tmpvalue = 0.0f;
-    if (tmpvalue > 0.75f)
-        tmpvalue = 0.75f;
-
-    return std::max<uint32>(uint32(damage * (1.0f - tmpvalue)), 1);
+    float mitigation = std::min(armor / (armor + ambl->KFactor), 0.85f);
+    return std::max<uint32>(damage * (1.0f - mitigation), 1);
 }
 
 uint32 Unit::CalcSpellResistance(Unit* victim, SpellSchoolMask schoolMask, SpellInfo const* spellInfo) const
diff --git a/src/server/game/Entities/Unit/Unit.h b/src/server/game/Entities/Unit/Unit.h
index 5eddf7cc6b5..76df842862e 100644
--- a/src/server/game/Entities/Unit/Unit.h
+++ b/src/server/game/Entities/Unit/Unit.h
@@ -2079,7 +2079,7 @@ class TC_GAME_API Unit : public WorldObject
         virtual bool IsImmunedToSpellEffect(SpellInfo const* spellInfo, uint32 index) const; // redefined in Creature
 
         bool IsDamageReducedByArmor(SpellSchoolMask damageSchoolMask, SpellInfo const* spellInfo = NULL, uint8 effIndex = MAX_SPELL_EFFECTS);
-        uint32 CalcArmorReducedDamage(Unit* victim, const uint32 damage, SpellInfo const* spellInfo, WeaponAttackType attackType = MAX_ATTACK);
+        uint32 CalcArmorReducedDamage(Unit* attacker, Unit* victim, const uint32 damage, SpellInfo const* spellInfo, WeaponAttackType attackType = MAX_ATTACK);
         uint32 CalcSpellResistance(Unit* victim, SpellSchoolMask schoolMask, SpellInfo const* spellInfo) const;
         void CalcAbsorbResist(Unit* victim, SpellSchoolMask schoolMask, DamageEffectType damagetype, uint32 const damage, uint32* absorb, uint32* resist, SpellInfo const* spellInfo = NULL);
         void CalcHealAbsorb(Unit* victim, SpellInfo const* spellInfo, uint32& healAmount, uint32& absorb);
diff --git a/src/server/game/Spells/Auras/SpellAuraEffects.cpp b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
index 78caf1ca816..87e3cc1bfc1 100644
--- a/src/server/game/Spells/Auras/SpellAuraEffects.cpp
+++ b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
@@ -5975,7 +5975,7 @@ void AuraEffect::HandlePeriodicDamageAurasTick(Unit* target, Unit* caster) const
         // Calculate armor mitigation
         if (caster->IsDamageReducedByArmor(GetSpellInfo()->GetSchoolMask(), GetSpellInfo(), GetEffIndex()))
         {
-            uint32 damageReductedArmor = caster->CalcArmorReducedDamage(target, damage, GetSpellInfo());
+            uint32 damageReductedArmor = caster->CalcArmorReducedDamage(caster, target, damage, GetSpellInfo());
             cleanDamage.mitigated_damage += damage - damageReductedArmor;
             damage = damageReductedArmor;
         }
@@ -6110,7 +6110,7 @@ void AuraEffect::HandlePeriodicHealthLeechAuraTick(Unit* target, Unit* caster) c
     // Calculate armor mitigation
     if (caster->IsDamageReducedByArmor(GetSpellInfo()->GetSchoolMask(), GetSpellInfo(), GetEffIndex()))
     {
-        uint32 damageReductedArmor = caster->CalcArmorReducedDamage(target, damage, GetSpellInfo());
+        uint32 damageReductedArmor = caster->CalcArmorReducedDamage(caster, target, damage, GetSpellInfo());
         cleanDamage.mitigated_damage += damage - damageReductedArmor;
         damage = damageReductedArmor;
     }
diff --git a/src/server/scripts/Commands/cs_misc.cpp b/src/server/scripts/Commands/cs_misc.cpp
index 874c6b9ff51..7ad80352995 100644
--- a/src/server/scripts/Commands/cs_misc.cpp
+++ b/src/server/scripts/Commands/cs_misc.cpp
@@ -2321,7 +2321,7 @@ public:
         SpellSchoolMask schoolmask = SpellSchoolMask(1 << school);
 
         if (handler->GetSession()->GetPlayer()->IsDamageReducedByArmor(schoolmask))
-            damage = handler->GetSession()->GetPlayer()->CalcArmorReducedDamage(target, damage, NULL, BASE_ATTACK);
+            damage = handler->GetSession()->GetPlayer()->CalcArmorReducedDamage(handler->GetSession()->GetPlayer(), target, damage, NULL, BASE_ATTACK);
 
         char* spellStr = strtok((char*)NULL, " ");