Core/Spells: Fixed resist calculations for spells with multiple schools. Thx to Shauren for tips

Closes #3875

4 files changed, 17 insertions, 5 deletions

diff --git a/src/server/game/Entities/Unit/Unit.cpp b/src/server/game/Entities/Unit/Unit.cpp
index f9d049a51b8..f6798d08708 100755
--- a/src/server/game/Entities/Unit/Unit.cpp
+++ b/src/server/game/Entities/Unit/Unit.cpp
@@ -1584,7 +1584,7 @@ void Unit::CalcAbsorbResist(Unit* victim, SpellSchoolMask schoolMask, DamageEffe
     // Magic damage, check for resists
     if ((schoolMask & SPELL_SCHOOL_MASK_NORMAL) == 0)
     {
-        float victimResistance = float(victim->GetResistance(GetFirstSchoolInMask(schoolMask)));
+        float victimResistance = float(victim->GetResistance(schoolMask));
         victimResistance += float(GetTotalAuraModifierByMiscMask(SPELL_AURA_MOD_TARGET_RESISTANCE, schoolMask));
 
         if (Player* player = ToPlayer())
@@ -17386,7 +17386,7 @@ uint32 Unit::GetRemainingPeriodicAmount(uint64 caster, uint32 spellId, AuraType
     AuraEffectList const& periodicAuras = GetAuraEffectsByType(auraType);
     for (AuraEffectList::const_iterator i = periodicAuras.begin(); i != periodicAuras.end(); ++i)
     {
-        if ((*i)->GetCasterGUID() != caster || (*i)->GetId() != spellId || (*i)->GetEffIndex() != effectIndex || (*i)->GetTotalTicks() == 0)
+        if ((*i)->GetCasterGUID() != caster || (*i)->GetId() != spellId || (*i)->GetEffIndex() != effectIndex || !(*i)->GetTotalTicks())
             continue;
         amount += uint32(((*i)->GetAmount() * std::max<int32>((*i)->GetTotalTicks() - int32((*i)->GetTickNumber()), 0)) / (*i)->GetTotalTicks());
         break;
@@ -17402,6 +17402,17 @@ void Unit::SendClearTarget()
     SendMessageToSet(&data, false);
 }
 
+uint32 Unit::GetResistance(SpellSchoolMask mask) const
+{
+    int32 resist = -1;
+    for (int i = SPELL_SCHOOL_NORMAL; i < MAX_SPELL_SCHOOL; ++i)
+        if (mask & (1 << i) && (resist < 0 || resist > int32(GetResistance(SpellSchools(i)))))
+            resist = int32(GetResistance(SpellSchools(i)));
+
+    // resist value will never be negative here
+    return uint32(resist);
+}
+
 void CharmInfo::SetIsCommandAttack(bool val)
 {
     m_isCommandAttack = val;
diff --git a/src/server/game/Entities/Unit/Unit.h b/src/server/game/Entities/Unit/Unit.h
index 36844d97b67..02e78276782 100755
--- a/src/server/game/Entities/Unit/Unit.h
+++ b/src/server/game/Entities/Unit/Unit.h
@@ -1346,6 +1346,7 @@ class Unit : public WorldObject
         void SetArmor(int32 val) { SetResistance(SPELL_SCHOOL_NORMAL, val); }
 
         uint32 GetResistance(SpellSchools school) const { return GetUInt32Value(UNIT_FIELD_RESISTANCES+school); }
+        uint32 GetResistance(SpellSchoolMask mask) const;
         void SetResistance(SpellSchools school, int32 val) { SetStatInt32Value(UNIT_FIELD_RESISTANCES+school, val); }
 
         uint32 GetHealth()    const { return GetUInt32Value(UNIT_FIELD_HEALTH); }
@@ -1517,7 +1518,7 @@ class Unit : public WorldObject
             {
                 value = soft_cap + ((value - soft_cap) / 2);
             }
-        
+
             return value;
         }
         uint32 GetUnitMeleeSkill(Unit const* target = NULL) const { return (target ? getLevelForTarget(target) : getLevel()) * 5; }
diff --git a/src/server/game/Entities/Vehicle/Vehicle.cpp b/src/server/game/Entities/Vehicle/Vehicle.cpp
index edd8745d246..fe018ec78ce 100755
--- a/src/server/game/Entities/Vehicle/Vehicle.cpp
+++ b/src/server/game/Entities/Vehicle/Vehicle.cpp
@@ -177,7 +177,7 @@ void Vehicle::ApplyAllImmunities()
         case 244: // Wintergrasp
         case 510: // Isle of Conquest
             _me->SetControlled(true, UNIT_STAT_ROOT);
-            // why we need to apply this? we can simple add immunities to slow mechamic in DB
+            // why we need to apply this? we can simple add immunities to slow mechanic in DB
             _me->ApplySpellImmune(0, IMMUNITY_STATE, SPELL_AURA_MOD_DECREASE_SPEED, true);
             break;
         default:
diff --git a/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp b/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp
index 5b612942435..7ef2e887a1d 100644
--- a/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp
+++ b/src/server/scripts/Northrend/IcecrownCitadel/boss_sindragosa.cpp
@@ -971,7 +971,7 @@ class spell_sindragosa_s_fury : public SpellScriptLoader
                 if (!GetHitUnit()->isAlive() || !_targetCount)
                     return;
 
-                float resistance = float(GetHitUnit()->GetResistance(GetFirstSchoolInMask(SpellSchoolMask(GetSpellInfo()->SchoolMask))));
+                float resistance = float(GetHitUnit()->GetResistance(SpellSchoolMask(GetSpellInfo()->SchoolMask)));
                 uint32 minResistFactor = uint32((resistance / (resistance + 510.0f))* 10.0f) * 2;
                 uint32 randomResist = urand(0, (9 - minResistFactor) * 100)/100 + minResistFactor;