Feature [TFS 1.3] Monster Levels

Klank said:

Monster Damage Bug

Greetings. I would like to point out a very impactful bug with this system and the fix for it:

onCombatChangeHealth is a recursive function and calls itself in case it has a onChangeHealth lua callback. In that case the damage is increases not only the first time but also the second time it goes into the function. Because the callback is only executed once, it is not infinitive. This is because they check "damage.origin != ORIGIN_NONE" to avoid that.
So this also must be checked for the monster bonus damage to not double it twice.

Example: (You use a onHealthChange creatureevent to reduce the damage by 10% )
1. you take damage and onCombatHealth activates, calculates monster damage
2. .. Reaches down to "target->getCreatureEvents(CREATURE_EVENT_HEALTHCHANGE)", check any change of damage on the onChangeHealth lua callback.
3. Returns modified damage ( 10% reduced damage) to onCombatHealth and sets damage.origin = ORIGIN_NONE
4. onCombatHealth activate, calculating monster damage again (increasing it again).
5. Ignores events this time due to ORIGIN_NONE.
6. deal damage to player.

This means that the intention of reducing damage, will actually increase it instead (of course based on your bonus damage)


Solution
Replace this:

C++:

Monster* monster = attacker ? attacker->getMonster() : nullptr;
    if (monster && monster->getLevel() > 0) {
        float bonusDmg = g_config.getFloat(ConfigManager::MLVL_BONUSDMG) * monster->getLevel();
        if (bonusDmg != 0.0) {
            if (damage.primary.value < 0) {
                damage.primary.value += std::round(damage.primary.value * bonusDmg);
            }
            if (damage.secondary.value < 0) {
                damage.secondary.value += std::round(damage.secondary.value * bonusDmg);
            }
        }
    }

with this, (do this for CombatChangeHealth and CombatChangeMana):

Code:

    Monster* monster = attacker ? attacker->getMonster() : nullptr;
    if (monster && monster->getLevel() > 0 && damage.origin != ORIGIN_NONE) {
        float bonusDmg = g_config.getFloat(ConfigManager::MLVL_BONUSDMG) * monster->getLevel();
        if (bonusDmg != 0.0) {
            if (damage.primary.value < 0) {
                damage.primary.value += std::round(damage.primary.value * bonusDmg);
            }
            if (damage.secondary.value < 0) {
                damage.secondary.value += std::round(damage.secondary.value * bonusDmg);
            }
        }
    }

in combatChangeHealth, add "damage.origin = ORIGIN_NONE;" below "manaDamage = std::min<int32_t>(targetPlayer->getMana(), healthChange);"
This is to not activate onHealthChange events again if you took damage that broke your manashield.

C++:

SpectatorVec spectators;
if (targetPlayer && target->hasCondition(CONDITION_MANASHIELD) && damage.primary.type != COMBAT_UNDEFINEDDAMAGE) {
    int32_t manaDamage = std::min<int32_t>(targetPlayer->getMana(), healthChange);
    if (manaDamage != 0) {
        if (damage.origin != ORIGIN_NONE) {
            const auto& events = target->getCreatureEvents(CREATURE_EVENT_MANACHANGE);
            if (!events.empty()) {
                for (CreatureEvent* creatureEvent : events) {
                    creatureEvent->executeManaChange(target, attacker, damage);
                }
                healthChange = damage.primary.value + damage.secondary.value;
                if (healthChange == 0) {
                    return true;
                }
                manaDamage = std::min<int32_t>(targetPlayer->getMana(), healthChange);
                damage.origin = ORIGIN_NONE;
            }
        }

Click to expand...

bool Game::combatChangeHealth(Creature* attacker, Creature* target, CombatDamage& damage)

bool Game::combatChangeMana(Creature* attacker, Creature* target, CombatDamage& damage)

Player* casterPlayer = caster ? caster->getPlayer() : nullptr;
--BELOW HERE
Monster* monster = caster ? caster->getMonster() : nullptr;

if (monster) {
    float bonusDmg = g_config.getFloat(ConfigManager::MLVL_BONUSDMG) * monster->getLevel();
    if (bonusDmg != 0.0) {
        damage.primary.value += std::round(damage.primary.value * bonusDmg);
        damage.secondary.value += std::round(damage.secondary.value * bonusDmg);
    }
}