## Does GZDoom move things out of 3D floors

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Enjay

Posts: 26403
Joined: Tue Jul 15, 2003 4:58 pm
Location: Scotland

### Does GZDoom move things out of 3D floors

and, if so, is there a limit to the move?

Reason I'm asking is I made an area in a map that has lots of details on the floor (lots of broken tiles etc) that sat 1 unit above the surrounding floor.

Problem was, the 1 unit high edge of these details was enough to "catch" bouncing grenades and bounce them back in an unpredictable way.

My solution was to fill the lower area of the floor with an invisible solid 3D floor that is 1 unit about the visible floor. I guessed that I might have to move any enemies and items placed on this area up by 1 unit (i.e. set their z value to 1).

I started doing this but, on testing the map, all the enemies (whether I had changed their heights or not) were free to move around and were, presumably, on top of the invisible 3D floor.

So, can I ask what GZDoom does when encountering an item placed with its feet inside a 3D floor? My tests as to how things behave (when trying different thicknesses of 3D floor) have been inconclusive. I *think* it might be that if the floor is less than or equal to the step height of an enemy, it can free itself. I'm less sure about static decorations and pickups. I *think* they might just get stuck in the floor and my initial 1 unit thick floor was so thin the effect wasn't really noticeable.
Kappes Buur

Posts: 4010
Joined: Thu Jul 17, 2003 12:19 am

### Re: Does GZDoom move things out of 3D floors

As far as I can tell, all things are correctly on top of a 3D floor when the thing Z height is equal to
the 3D floor top height.

When the thing Z height is more than the 3D floor top height, even by one height unit, then the things
will fall onto the 3D floor.

When an actor Z height is less than the 3D floor top height, even by one height unit, then the actor
will fall onto the real floor beneath.

With one exception, the short firesticks bounce up and down, which is really noticable on 3D floors.
Enjay

Posts: 26403
Joined: Tue Jul 15, 2003 4:58 pm
Location: Scotland

### Re: Does GZDoom move things out of 3D floors

Kappes Buur wrote:When an actor Z height is less than the 3D floor top height, even by one height unit, then the actor
will fall onto the real floor beneath.
Sorry, I wasn't entirely clear about my particular setup. In the case where I noticed that actors could move even if the spawned in a 3D floor, the real floor is at height 0 and the 3D floor is at heights top 1, bottom 0 (i.e. a very thin 3D floor just sitting on top of the real one).

So although enemies and items might drop to the floor below, it is only 1 unit below the top of the 3D floor and enemies, and maybe other things, seem to be able to step up onto the 3D floor and move around as if they had been placed on top of the 3D floor.

If I make the 3D floor top 32, bottom 0, then enemies are stuck in the floor. If I make it top 24, bottom 0 (24 being the default max step height) they can move.
boris
Posts: 699
Joined: Tue Jul 15, 2003 3:37 pm

### Re: Does GZDoom move things out of 3D floors

I don't have an answer for your question, but did you consider using models for the floor detail? It's really easy to export geometry as a model with UDB, since it'll also (optionally) generate DECORATE or ZScript code that makes it possible to use the model/actor immediately.

Enjay

Posts: 26403
Joined: Tue Jul 15, 2003 4:58 pm
Location: Scotland

### Re: Does GZDoom move things out of 3D floors

I knew that UDB could export models, but I didn't realise how much of the export process it could handle. I'm sure that video will be really useful to me at some point. Thanks for posting it.

I did consider using models for the map ion question (I considered a couple of different ways in which I might use them. However, after a bit of trial and error, in this particular case the solution that I came up with was easiest and most effective for what I was trying to achieve.

So the map is doing exactly what I wanted but it prompted my question so that, in future, I would have a better idea as to what the engine does in this kind of situation.
Deon
Posts: 207
Joined: Thu Oct 08, 2020 10:44 am

### Re: Does GZDoom move things out of 3D floors

You could also use non-solid 3dfloors for detailing if I understood your desire right.
Enjay

Posts: 26403
Joined: Tue Jul 15, 2003 4:58 pm
Location: Scotland

### Re: Does GZDoom move things out of 3D floors

Yup, you probably have understood.

Non-solid 3D floors would indeed do the job too. I went with what I did because I could get away with one (admittedly big-ish area-wise) 3D floor to fill in the gaps between the details rather than needing a 3D floor for each of the details.