Curious about engine bugs

[Phobos Anomaly]

So, one of my favorite things to read about and research are engine bugs and glitches in idTech 1, and I've spent many hours trying to recreate them just for fun. I noticed this one ("Phantom fireball explosions") on the "Engine bug" page at doomwiki.org a while back, but it was red, indicating it has no article. I figured it would eventually get a page, but still hasn't, so I figured I would reach out to the technically inclined here and see if anyone can explain exactly what this bug is, how it occurs (if known) and other technical information regarding it. That would be great! I figured people like @fraggle and @Quasar would be the best sources for this info. Thanks!

 

 

[Wagi]

My best guess is that this is referring to a potential occurrence where a fireball goes through a wall (fairly common with Mancubus fireballs) and hits some sort of a barrier in the void (typically a change in sector height) an extremely large distance away. The sound code overflows and you hear fireballs exploding at full volume as if they are right next to you.

 

If I remember correctly, a similar overflow can occur with monster melee attacks --- if you run far enough into the void you will suddenly be bitten and scratched by every monster in the level.

Edited March 31, 2020 by Wagi

[Phobos Anomaly]

7 minutes ago, Wagi said:

My best guess is that this is referring to a potential occurrence where a fireball goes through a wall (fairly common with Mancubus fireballs) and hits some sort of a barrier in the void (typically a change in sector height) an extremely large distance away. The sound code overflows and you hear fireballs exploding at full volume as if they are right next to you.

 

If I remember correctly, a similar overflow can occur with monster melee attacks --- if you run far enough into the void you will suddenly be bitten and scratched by every monster in the level.

 

Thank you! I knew of the fireball going through walls, but I hadn't considered that it was related!

[Maximum Matt]

11 hours ago, Wagi said:

if you run far enough into the void you will suddenly be bitten and scratched by every monster in the level.

Well, thanks for ruining noclip mode for me

[Xeriphas1994]

11 hours ago, Wagi said:

My best guess is that this is referring to a potential occurrence where a fireball goes through a wall (fairly common with Mancubus fireballs) and hits some sort of a barrier in the void (typically a change in sector height) an extremely large distance away. The sound code overflows and you hear fireballs exploding at full volume as if they are right next to you.

 

That was indeed the intended meaning. The discussion page links to a few LMPs.

[Phobos Anomaly]

1 hour ago, Maximum Matt said:

Well, thanks for ruining noclip mode for me

 

I just tried it, and yep, it happens. You also suddenly hear every sound in the level at full volume, which is due to the sound code overflowing, as @Wagi said.