Bouncing projectile, poison damage, and SpecialMissileHit()

[D2JK]

Hi all,

Background: a long while ago, I created a projectile which uses the PoisonDamage property apply a damage-over-time effect. Since this was of "fire" type, I also wanted the initial applications of the "poison" to start a visual burning effect, using particle effects and a thinker for this purpose. This thinker would only be created if the monster had no existing PoisonDamageDuration on it when the projectile hit. Now, since poison damage seems to be already applied by the time the projectile's Death-state and its actions are reached, I needed to work around this problem by performing the relevant checks earlier in SpecialMissileHit function instead, and saving the result in a custom class variable which I could later compare against, in the Death state (see code below).

Code: Select all

override int SpecialMissileHit(actor victim) {
    lastVictim = victim;
    lastVictimHasPoisonDuration = victim.PoisonDurationReceived;

    return Super.SpecialMissileHit(victim);
}

So today I wanted to apply the same concept to a new, bouncing projectile. I was surprised to find out that for a bouncing projectile (namely, using BounceType "Hexen"), even my above workaround would not work; if the projectile can bounce and a monster is hit, then in the last call to SpecialMissileHit(), the poison damage seems to be already applied. It does not matter whether or not this was a direct hit (ie. no actual bouncing having happened after the projectile was shot). If I simply comment out the BounceType property, then the PoisonDamage will not yet be applied in the last call to SpecialMissileHit, so in that case, my previous workaround will work again.

I have to think about how I work around this problem for bouncing projectiles as well. Perhaps even more checks and new class variables to hold the results are required (of course, better ideas and suggestions are welcome).

But I'm also a bit curious if this change in timing of PoisonDamage application (relative to the last SpecialMissileHit call) is intended to happen for bouncing projectiles, and what exactly explains it?

[D2JK]

Actually, it crossed my mind to try reading the poison damage, duration and period properties of the projectile itself. Since this turned out to be possible in ZScript, I was able to simplify the code by instead checking if the monster's (blockingMObj) PoisonDurationReceived after the hit is equal to projectile's PoisonDuration value. This check works for my purposes since I'm using the ADDITIVEPOISONDURATION flag in these projectiles.

Problem solved, thanks all.