Does everything in the game have infinite height? I thought I've seen missiles and projectiles go under/over me?

[Kute]

I'm a bit embarrassed because I've never really paid attention to this stuff in my many hours of playing, outside of using rockets to blow up stuff below a lift and not trying to run off a ledge I know there's monsters lined up along. Outside of those situations, you just never really think about height. I don't use freelook.

 

But I thought I've seen like arachnotron beans go overhead on me plenty of times, and rockets too? If I'm not imagining that in the heat of battle, how come they can't distinguish "height" in other stuff just for the sake of feeling a bit more 3dimensional?

 

Thanks in advance.

[m8f]

https://doomwiki.org/wiki/Z-clipping
 

Quote

In the original implementation as utilized in Doom itself, solid objects may not overlap on the x-y plane even if they would not visibly or tangibly overlap given their stated heights and positions on the z axis. Doom features a limited z-clipping that is only designed for projectiles and hitscan attacks, and for allowing moving solid objects, like monsters, to be able to enter a sector depending on its floor and ceiling heights. Aside from that, a given thing's height or z-coordinates are largely ignored by the engine, causing actors to have apparently infinite height.

 

Edited January 25, 2022 by m8f

[Edward850]

I feel it's weird that you would question the existence of gameplay behavior you've directly observed yourself and can test.

I think you've been watching too many Game Theorists videos. :P

Edited January 25, 2022 by Edward850

[Kute]

41 minutes ago, m8f said:

https://doomwiki.org/wiki/Z-clipping
 

 

I see, so I wasn't imagining that projectiles can go under/over. I wonder if it was impossible to utilize a z-axis for things other than projectiles then? Or if it would have just been a ton of work? Or maybe they didn't see the issue with it as it doesn't pop up all that much?

[Gez]

Basically, movement in the Doom engine is a pile of ad-hoc code glued together. Projectiles, players, and monsters use different methods to move. Vertical collision detection with things is performed for when projectiles move, but not when players or monsters move. For the latter, only horizontal collision detection with things is performed.

 

BTW projectiles only collide on their turn. You cannot collide with a projectile; you can only put yourself in a position where a projectile will collide with you.

[Ludi]

54 minutes ago, Edward850 said:

I feel it's weird that you would question the existence of gameplay behavior you've directly observed yourself and can test.

 

You can see how something happens, and still be able to ask why it happens.

[Shepardus]

 I recommend this video if you haven't already seen it:

 

[Bauul]

1 hour ago, Kute said:

I wonder if it was impossible to utilize a z-axis for things other than projectiles then?

 

Not at all. Enabling the full z-axis collisions for all Things was one of the first changes source code modders did.

 

Carmack likely left it the way it is because it was quicker for the engine to process in real-time (a huge concern at the time) and infrequently impacts gameplay, when you think about the level design for Doom 1.

[Edward850]

5 hours ago, Sr_Ludicolo said:

 

You can see how something happens, and still be able to ask why it happens.

Certainly, but why wasn't what was being initially asked here.

Edited January 25, 2022 by Edward850

[SiFi270]

In Vanilla Raven/Strife and very early versions of ZDoom, it's fairly common to see a flying monster "land" on another actor and get stuck. I love it when I get to cheese Maulotaurs like that. Not so much when gargoyles or Strife stalkers use it to cheese me.

[Kute]

21 hours ago, Sr_Ludicolo said:

 

You can see how something happens, and still be able to ask why it happens.

 

Yea, this. I don't think it was that bad of a question. Some stuff seems to respect a z-axis, some stuff doesn't. I just wanted to know what the deal was with that. I would have thought a prominent Doom forum was the place to ask.

 

And while I was fairly sure I had seen projectiles go over/under me, I wasn't 100%. You start second guessing yourself, like maybe you realize early on you have infinite height and you instinctively make sure you're nowhere near the projectiles, or you just frankly aren't noticing what exactly hits you or doesn't, or fuck, maybe it really doesn't even happen much - as let's face it, the old games don't make a lot of vertical demands.

 

Also, I haven't played legitimate Doom since the mid 90's. I use GZDoom. Frankly, I don't know if it's a perfect emulation, or a good one, or a poor one. I don't know if it's accurate. It was just what showed up on google half a decade ago when I decided I wanted to blow up some imps like I was 10 again

 

IDK when I'm playing games, I'm just going, not really thinking too much about what specifically is happening. 

Like in the last month I went from struggling horrifically on NM Doom Eternal to plowing the fucc outta master lvls, and my "indepth" knowledge of the specifics of the game hasn't really changed. I don't really know anything more about the monsters than I learned on my first HMP half play-through. That's why it's fun getting better at these games, you don't even really know why, but suddenly fights that were so difficult 30 hours ago are not considerations anymore. It's neat. It's satisfying.