Cacodemons and lost souls flying away

What exactly causes flying monsters to fly away when shot? Sometimes they fly away only a bit and then charge towards you again, other times it seems like they won't stop flying away until they hit something (very annoying in big open maps with a long distance to the horizon, like in that Mount Doom map by Foodles). Can I get rid of this by incresing their mass significantly or maybe doing some other changes?

Whatever it is, it's hilarious to see how fast you can 'push' a Cacodemon before it dies.

What source port are you playing with?

It happens when they have a momentum away from the direction they want to move in which is too great to overcome via the small thrusts they use to normally move toward you, as far as I know. I'm sure like with all things in the Doom engine, the full truth is more complicated than anybody would care to know.

So if your theory is right, just significantly increasing their mass should be enough to get rid of this behavior? (the momentum will be very low (weak? small? dunno what word to use here) even if you shoot at them a lot). Thanks, I'll experiment with this.

Jayextee: maybe it's funny to some people but at least for speedrunners it can be quite annoying (waiting forever for the cacodemon to get back to the position where you can hit him and get 100% kills). And it makes some gameplay situations difficult to orchestrate. I want to make an "islands in the sky" type map and it will have a caco swarm scene at some point. I don't want the player to be able to send all them flying to the moon. :)

joe: prboom-plus with vanilla compatibility settings

The obvious solution is to give them negative mass, so shooting them makes them come closer.

(Although that would probably introduce some nasty bugs somewhere down the line.)

Memfis said:

I want to make an "islands in the sky" type map and it will have a caco swarm scene at some point. I don't want the player to be able to send all them flying to the moon. :)

You can always put monster-blocking lines some distances away from the player-accessible zones so that cacos and lost souls don't get blown away too far.

Gez said:

You can always put monster-blocking lines some distances away from the player-accessible zones so that cacos and lost souls don't get blown away too far.

Heh. I did exactly that in High / Low 5 to overcome this issue.

If we're wanting to talk physics, I could see the fact they fly away being represented as a form of bullet blowback. Y'know, because bullets = fast, and fast = forced away and that = blowback.

Scripting-wise, it's just weird phrases I hope to understand. I'm going with my blowback idea.

If you don't want them to fly away that far , then add a "block monster" line around the arena.
That way you won't see a red dot floating in the air.

Block monster lines are a bit limiting, with the layout I have in my head the cacos will have problems reaching some areas. I'll try changing the mass first but thanks for the suggestions.

In ZDoom, giving a monster a ridiculously high mass does indeed stop it being knocked around (although with enough force it will still slowly get knocked), even if it takes something like a BFG blast. I'm assuming the mass/impulse stuff in ZDoom isn't much improved off of vanilla, TBH, so that should work.

The reason they get knocked about so helplessly is because they're not in contact with the ground, so there's no friction to help slow them when they get some momentum going. You'll notice when they're dead or against the ground they don't slide anywhere near as much.

You could also have a sky-bleeding low ceiling ring around the island, lower than your shooting height so they'll hit it but it will just look like sky, and also they can fly under it if they need to go outside the ring.

Instead of blocky lines, you could put teleporting lines in the distance.