[little fix] SPELLMOD_SPELL_BONUS_DAMAGE calculation

[Auntie Mangos]

What bug does the patch fix? What features does the patch add?

Fixes the "SPELLMOD_SPELL_BONUS_DAMAGE", which should rather be added to the default coefficient, than multiply it.

For example talent Empowered Corruption Rank 3 (Increases the damage of your Corruption spell by an amount equal to 36% of your spell power.) has value 6, meaning that every tick should take an additional 6% of spell power.

The default coefficient od Corruption is 0,2 per tick, after this modifier it should be 0,26.

According to the current formula, it is 0,2 * 1,06 = 0,212. This goes for all spells, using this modifier...

To confirm that, you may take a look at wowwiki, which says:

Corruption 20% (per tick) (26% with Empowered Corruption) (31% with Empowered Corruption & Everlasting Affliction)

For which repository revision was the patch created?

Rev. 9020

Is there a thread in the bug report section or at lighthouse? If yes, please add a link to the thread.

Found this:

http://getmangos.eu/community/viewtopic.php?id=2004

Who has been writing this patch? Please include either forum user names or email addresses.

Me, reeshack

diff --git a/src/game/Unit.cpp b/src/game/Unit.cpp
index 3d17605..d59a2d4 100644
--- a/src/game/Unit.cpp
+++ b/src/game/Unit.cpp
@@ -8754,7 +8754,7 @@ uint32 Unit::SpellDamageBonus(Unit *pVictim, SpellEntry const *spellProto, uint3

    float LvlPenalty = CalculateLevelPenalty(spellProto);
    // Spellmod SpellDamage
-    float SpellModSpellDamage = 100.0f;
+    float SpellModSpellDamage = 0.0f;
    if(Player* modOwner = GetSpellModOwner())
        modOwner->ApplySpellMod(spellProto->Id,SPELLMOD_SPELL_BONUS_DAMAGE,SpellModSpellDamage);
    SpellModSpellDamage /= 100.0f;
@@ -8771,7 +8771,7 @@ uint32 Unit::SpellDamageBonus(Unit *pVictim, SpellEntry const *spellProto, uint3
        if (bonus->ap_bonus)
            DoneTotal += int32(bonus->ap_bonus * GetTotalAttackPowerValue(BASE_ATTACK) * stack);

-        DoneTotal  += int32(DoneAdvertisedBenefit * coeff * SpellModSpellDamage);
+        DoneTotal  += int32(DoneAdvertisedBenefit * (coeff + SpellModSpellDamage));
        TakenTotal += int32(TakenAdvertisedBenefit * coeff);
    }
    // Default calculation

Alternative (and better) patch by darkstalker:

http://getmangos.eu/community/viewtopic.php?id=10609

[Auntie Mangos]

That apply spell mod includes both multiplicative and additive part, so if you apply it to 0 you lose the multiplicative part. Besides that you forgot SpellHealingBonus.

I already had a tested patch for this:

http://getmangos.eu/community/viewtopic.php?id=10609

[reeshack]

I see...well your patch works correctly and does exactly what i wanted to fix so I won't update mine with reference to yours...