Core/Scripts: Expose calculated spell value variance to scripts

Port From (https://github.com/TrinityCore/TrinityCore/commit/701532f9f033547a5fc2d0b594d04f6349cb441b)

Source/Game/Scripting/SpellScript.cs

@@ -914,6 +914,28 @@ namespace Game.Scripting
             m_spell.damage = value;
         }
 
+        public float GetEffectVariance()
+        {
+            if (!IsInEffectHook())
+            {
+                Log.outError(LogFilter.Scripts, $"Script: `{m_scriptName}` Spell: `{m_scriptSpellId}`: function SpellScript::GetEffectVariance was called, but function has no effect in current hook!");
+                return 0.0f;
+            }
+
+            return m_spell.variance;
+        }
+
+        public void SetEffectVariance(float variance)
+        {
+            if (!IsInEffectHook())
+            {
+                Log.outError(LogFilter.Scripts, $"Script: `{m_scriptName}` Spell: `{m_scriptSpellId}`: function SpellScript::SetEffectVariance was called, but function has no effect in current hook!");
+                return;
+            }
+
+            m_spell.variance = variance;
+        }
+        
         // returns: cast item if present.
         public Item GetCastItem() { return m_spell.m_CastItem; }
 

Source/Game/Spells/Spell.cs

@@ -4587,7 +4587,7 @@ namespace Game.Spells
             destTarget = m_destTargets[spellEffectInfo.EffectIndex].Position;
             effectInfo = spellEffectInfo;
 
-            damage = CalculateDamage(spellEffectInfo, unitTarget, out _variance);
+            damage = CalculateDamage(spellEffectInfo, unitTarget, out variance);
 
             bool preventDefault = CallScriptEffectHandlers(spellEffectInfo.EffectIndex, mode);
 
@@ -8001,7 +8001,7 @@ namespace Game.Spells
         public WorldLocation destTarget;
         public int damage;
         public SpellMissInfo targetMissInfo;
-        float _variance;
+        public float variance;
         SpellEffectHandleMode effectHandleMode;
         public SpellEffectInfo effectInfo;
         // used in effects handlers

Source/Game/Spells/SpellEffects.cs

@@ -168,7 +168,7 @@ namespace Game.Spells
                 if (unitCaster != null && apply_direct_bonus)
                 {
                     uint bonus = unitCaster.SpellDamageBonusDone(unitTarget, m_spellInfo, (uint)damage, DamageEffectType.SpellDirect, effectInfo);
-                    damage = (int)(bonus + (bonus * _variance));
+                    damage = (int)(bonus + (bonus * variance));
                     damage = (int)unitTarget.SpellDamageBonusTaken(unitCaster, m_spellInfo, (uint)damage, DamageEffectType.SpellDirect);
                 }
 
@@ -688,7 +688,7 @@ namespace Game.Spells
             if (unitCaster != null)
             {
                 uint bonus = unitCaster.SpellDamageBonusDone(unitTarget, m_spellInfo, (uint)damage, DamageEffectType.SpellDirect, effectInfo);
-                damage = (int)(bonus + (bonus * _variance));
+                damage = (int)(bonus + (bonus * variance));
                 damage = (int)unitTarget.SpellDamageBonusTaken(unitCaster, m_spellInfo, (uint)damage, DamageEffectType.SpellDirect);
             }
 
@@ -810,7 +810,7 @@ namespace Game.Spells
             else
             {
                 uint bonus = unitCaster.SpellHealingBonusDone(unitTarget, m_spellInfo, (uint)addhealth, DamageEffectType.Heal, effectInfo);
-                addhealth = (int)(bonus + (uint)(bonus * _variance));
+                addhealth = (int)(bonus + (uint)(bonus * variance));
             }
 
             addhealth = (int)unitTarget.SpellHealingBonusTaken(unitCaster, m_spellInfo, (uint)addhealth, DamageEffectType.Heal);
@@ -856,7 +856,7 @@ namespace Game.Spells
             if (unitCaster)
                 heal = unitCaster.SpellHealingBonusDone(unitTarget, m_spellInfo, heal, DamageEffectType.Heal, effectInfo);
 
-            heal += (uint)(heal * _variance);
+            heal += (uint)(heal * variance);
             if (unitCaster)
                 heal = unitTarget.SpellHealingBonusTaken(unitCaster, m_spellInfo, heal, DamageEffectType.Heal);
 
@@ -877,7 +877,7 @@ namespace Game.Spells
             if (unitCaster != null)
                 unitCaster.SpellDamageBonusDone(unitTarget, m_spellInfo, (uint)damage, DamageEffectType.SpellDirect, effectInfo);
 
-            damage = (int)(bonus + (bonus * _variance));
+            damage = (int)(bonus + (bonus * variance));
 
             if (unitCaster != null)
                 damage = (int)unitTarget.SpellDamageBonusTaken(unitCaster, m_spellInfo, (uint)damage, DamageEffectType.SpellDirect);