[11510] Implement SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT (288) and related spell 19263.

Original patchs provided by KAPATEJIb and Roshnak.

src/game/Spell.cpp

@@ -3037,8 +3037,11 @@ void Spell::cast(bool skipCheck)
             break;
         case SPELLFAMILY_HUNTER:
         {
+            // Deterrence
+            if (m_spellInfo->Id == 19263)
+                AddPrecastSpell(67801);
             // Kill Command
-            if (m_spellInfo->Id == 34026)
+            else if (m_spellInfo->Id == 34026)
             {
                 if (m_caster->HasAura(37483))               // Improved Kill Command - Item set bonus
                     m_caster->CastSpell(m_caster, 37482, true);// Exploited Weakness

src/game/SpellAuraDefines.h

@@ -323,7 +323,7 @@ enum AuraType
     SPELL_AURA_MOD_ATTACK_POWER_OF_ARMOR = 285,
     SPELL_AURA_ABILITY_PERIODIC_CRIT = 286,
     SPELL_AURA_DEFLECT_SPELLS = 287,
-    SPELL_AURA_288 = 288,
+    SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT = 288,
     SPELL_AURA_289 = 289,
     SPELL_AURA_MOD_ALL_CRIT_CHANCE = 290,
     SPELL_AURA_MOD_QUEST_XP_PCT = 291,

src/game/SpellAuras.cpp

@@ -338,7 +338,7 @@ pAuraHandler AuraHandler[TOTAL_AURAS]=
     &Aura::HandleAuraModAttackPowerOfArmor,                 //285 SPELL_AURA_MOD_ATTACK_POWER_OF_ARMOR  implemented in Player::UpdateAttackPowerAndDamage
     &Aura::HandleNoImmediateEffect,                         //286 SPELL_AURA_ABILITY_PERIODIC_CRIT      implemented in Aura::IsCritFromAbilityAura called from Aura::PeriodicTick
     &Aura::HandleNoImmediateEffect,                         //287 SPELL_AURA_DEFLECT_SPELLS             implemented in Unit::MagicSpellHitResult and Unit::MeleeSpellHitResult
-    &Aura::HandleNULL,                                      //288 increase parry/deflect, prevent attack (single spell used 67801)
+    &Aura::HandleNoImmediateEffect,                         //288 SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT percent from normal parry/deflect applied to from behind attack case (single spell used 67801, also look 4.1.0 spell 97574)
     &Aura::HandleUnused,                                    //289 unused (3.2.2a)
     &Aura::HandleAuraModAllCritChance,                      //290 SPELL_AURA_MOD_ALL_CRIT_CHANCE
     &Aura::HandleNoImmediateEffect,                         //291 SPELL_AURA_MOD_QUEST_XP_PCT           implemented in Player::GiveXP

src/game/SpellMgr.cpp

@@ -2210,6 +2210,10 @@ bool SpellMgr::IsNoStackSpellDueToSpell(uint32 spellId_1, uint32 spellId_2) cons
                     ((spellInfo_2->SpellFamilyFlags & UI64LIT(0x4)) && (spellInfo_1->SpellFamilyFlags & UI64LIT(0x00000004000))))
                     return false;
 
+                // Deterrence
+                if (spellInfo_1->SpellIconID == 83 && spellInfo_2->SpellIconID == 83)
+                    return false;
+
                 // Bestial Wrath
                 if (spellInfo_1->SpellIconID == 1680 && spellInfo_2->SpellIconID == 1680)
                     return false;

src/game/Unit.cpp

@@ -2678,23 +2678,26 @@ MeleeHitOutcome Unit::RollMeleeOutcomeAgainst (const Unit *pVictim, WeaponAttack
     }
 
     // parry chances
-    // check if attack comes from behind, nobody can parry or block if attacker is behind
+    // check if attack comes from behind, nobody can parry or block if attacker is behind if not have
-    if (!from_behind)
+    if (!from_behind || pVictim->HasAuraType(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT))
     {
         // Reduce parry chance by attacker expertise rating
         if (GetTypeId() == TYPEID_PLAYER)
-            parry_chance-= int32(((Player*)this)->GetExpertiseDodgeOrParryReduction(attType)*100);
+            parry_chance -= int32(((Player*)this)->GetExpertiseDodgeOrParryReduction(attType)*100);
         else
             parry_chance -= GetTotalAuraModifier(SPELL_AURA_MOD_EXPERTISE)*25;
 
-        if(pVictim->GetTypeId()==TYPEID_PLAYER || !(((Creature*)pVictim)->GetCreatureInfo()->flags_extra & CREATURE_FLAG_EXTRA_NO_PARRY) )
+        if (parry_chance > 0 && (pVictim->GetTypeId()==TYPEID_PLAYER || !(((Creature*)pVictim)->GetCreatureInfo()->flags_extra & CREATURE_FLAG_EXTRA_NO_PARRY)))
         {
-            int32 tmp2 = int32(parry_chance);
+            parry_chance -= skillBonus;
-            if (   (tmp2 > 0)                                   // check if unit _can_ parry
+
-                && ((tmp2 -= skillBonus) > 0)
+            //if (from_behind) -- only 100% currently and not 100% sure way value apply
-                && (roll < (sum += tmp2)))
+            //    parry_chance = int32(parry_chance * (pVictim->GetTotalAuraMultiplier(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT) - 1);
+
+            if (parry_chance > 0 &&                         // check if unit _can_ parry
+                (roll < (sum += parry_chance)))
             {
-                DEBUG_FILTER_LOG(LOG_FILTER_COMBAT, "RollMeleeOutcomeAgainst: PARRY <%d, %d)", sum-tmp2, sum);
+                DEBUG_FILTER_LOG(LOG_FILTER_COMBAT, "RollMeleeOutcomeAgainst: PARRY <%d, %d)", sum - parry_chance, sum);
                 return MELEE_HIT_PARRY;
             }
         }
@@ -2987,14 +2990,20 @@ SpellMissInfo Unit::MeleeSpellHitResult(Unit *pVictim, SpellEntry const *spell)
     if (spell->Attributes & SPELL_ATTR_IMPOSSIBLE_DODGE_PARRY_BLOCK)
         return SPELL_MISS_NONE;
 
+    bool from_behind = !pVictim->HasInArc(M_PI_F,this);
+
     // Ranged attack cannot be parry/dodge only deflect
     if (attType == RANGED_ATTACK)
     {
-        // only if in front
+        // only if in front or special ability
-        if (pVictim->HasInArc(M_PI_F,this))
+        if (!from_behind || pVictim->HasAuraType(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT))
         {
             int32 deflect_chance = pVictim->GetTotalAuraModifier(SPELL_AURA_DEFLECT_SPELLS)*100;
-            tmp+=deflect_chance;
+
+            //if (from_behind) -- only 100% currently and not 100% sure way value apply
+            //    deflect_chance = int32(deflect_chance * (pVictim->GetTotalAuraMultiplier(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT) - 1);
+
+            tmp += deflect_chance;
             if (roll < tmp)
                 return SPELL_MISS_DEFLECT;
         }
@@ -3002,12 +3011,13 @@ SpellMissInfo Unit::MeleeSpellHitResult(Unit *pVictim, SpellEntry const *spell)
     }
 
     // Check for attack from behind
-    if (!pVictim->HasInArc(M_PI_F,this))
+    if (from_behind)
     {
         // Can`t dodge from behind in PvP (but its possible in PvE)
         if (GetTypeId() == TYPEID_PLAYER && pVictim->GetTypeId() == TYPEID_PLAYER)
             canDodge = false;
-        // Can`t parry
+        // Can`t parry without special ability
+        if (!pVictim->HasAuraType(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT))
             canParry = false;
     }
     // Check creatures flags_extra for disable parry
@@ -3065,6 +3075,9 @@ SpellMissInfo Unit::MeleeSpellHitResult(Unit *pVictim, SpellEntry const *spell)
         if (parryChance < 0)
             parryChance = 0;
 
+        //if (from_behind) -- only 100% currently and not 100% sure way value apply
+        //    parryChance = int32(parryChance * (pVictim->GetTotalAuraMultiplier(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT) - 1));
+
         tmp += parryChance;
         if (roll < tmp)
             return SPELL_MISS_PARRY;
@@ -3142,11 +3155,17 @@ SpellMissInfo Unit::MagicSpellHitResult(Unit *pVictim, SpellEntry const *spell)
     if (rand < tmp)
         return SPELL_MISS_MISS;
 
-    // cast by caster in front of victim
+    bool from_behind = !pVictim->HasInArc(M_PI_F,this);
-    if (pVictim->HasInArc(M_PI_F,this))
+
+    // cast by caster in front of victim or behind with special ability
+    if (!from_behind || pVictim->HasAuraType(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT))
     {
         int32 deflect_chance = pVictim->GetTotalAuraModifier(SPELL_AURA_DEFLECT_SPELLS)*100;
-        tmp+=deflect_chance;
+
+        //if (from_behind) -- only 100% currently and not 100% sure way value apply
+        //    deflect_chance = int32(deflect_chance * (pVictim->GetTotalAuraMultiplier(SPELL_AURA_MOD_PARRY_FROM_BEHIND_PERCENT)) - 1);
+
+        tmp += deflect_chance;
         if (rand < tmp)
             return SPELL_MISS_DEFLECT;
     }

src/shared/revision_nr.h

@@ -1,4 +1,4 @@
 #ifndef __REVISION_NR_H__
 #define __REVISION_NR_H__
- #define REVISION_NR "11509"
+ #define REVISION_NR "11510"
 #endif // __REVISION_NR_H__