Can I change a PolyObject floor texture?

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Heisanevilgenius
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Can I change a PolyObject floor texture?

Post by Heisanevilgenius »

I'm trying out PolyObjects and having trouble. I used map22 from Doom2 as a base for this, trying to make the little compass arrow spin around. I finally got it to work except the floor texture isn't changing. Can I have a little guidance please?
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Enjay
 
 
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Re: Can I change a PolyObject floor texture?

Post by Enjay »

Unfortunately, polybojects are only made of lines (in fact, usually, they are just made from single-sided lines with void space behind them). So, unless there is some trickery that I don't know about, they don't have any way to give them a flat on their floor - because they don't really have a floor. However, I have only ever used reasonably traditional polyobjects, so there might be a cunning trick that someone knows about that I don't.

Image


My suggestion would be to make a model, attach it to a no-collision actor and just have it spinning on the ground (models can be set to rotate via their modeldef definition for a nice smooth rotation). If you use doom textures for the model skin at a 1:1 scale, it will be almost indistinguishable from traditional Doom geometry.
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inkoalawetrust
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Re: Can I change a PolyObject floor texture?

Post by inkoalawetrust »

Enjay wrote: Wed Jun 18, 2025 9:42 am However, I have only ever used reasonably traditional polyobjects, so there might be a cunning trick that someone knows about that I don't.
There isn't. You can make a polyobject that appears to have a finite height by making it out of a raised floor (A lowered ceiling would probably work too but I haven't tried that before), and that also allows it to have decals sprayed on it, unlike doing it out of a 3D middle texture polyobject. But it will still not visually have a top or bottom plane, and all of them will still have infinite collision height, even though years ago the raised floor method DID actually limit the hitbox height of the polyobject, but I guess that got "fixed" around like 2022.
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Enjay
 
 
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Re: Can I change a PolyObject floor texture?

Post by Enjay »

Thanks for confirming. I thought that was probably the case but wasn't 100% sure.
Heisanevilgenius
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Re: Can I change a PolyObject floor texture?

Post by Heisanevilgenius »

I found an example WAD that uses a trick where the lines of the PolyObject create a line portal to a second dummy sector and it makes the floor appear properly. It works pretty well as long as the PolyObject doesn't move much, but there's a bunch of graphical glitches that happen at certain angles, especially if it's in constant motion.
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