High bridges & higher ceilings

The level I'm currently making will have a large, bridge-like walkway connecting the main buildings. The sector around it (which uses F_SKY1 for both flats) has 256 for the ceiling and -640 (for now) for the floor.

My biggest question is this: I've seen it done where you can walk on a platform that seems to have no floor, and side textures of STEPTOP or something similar, which don't repeat. This is one of those tricks that uses a self-refrencing sector inside the platform. Basically, I'd like to use that texture effect (so the same texture isn't displayed for 640+ units down), without making an "invisible" floor. Is that possible at all?

Other, less important question: WadAuthor keeps telling me that some of the sectors I made will crash older game engines because their ceiling/floor differences are too high. What engines, what versions specifically will crash upon seeing or being in such a sector? I heard that only the really old ones have this problem, but I figure it'd be a good idea to know which ones, so I can put that in the text file under bugs (for the .000001% of people who DO use such an engine).

To make the STEPTOP texture not repeat, you have to use it as a "main" texture, not a "below" texture. You can place it where you want by y-offset.

Making a sector self-referencing is a key in its not requiring a floor flat, or not displaying the flat if it has one assigned, and also in its not requiring any below or lower sidedef texture. I guess the only drawback to this method is that you can't ordinarily walk "under" such a bridge, although a few clever people around here know a way to use instantly-moving sectors to fake the effect of walking under a bridge in a vanilla doom wad.

I just use zdoom's invisible bridge objects. :)

There are two problems with that method.. first of all, I already have a main texture on those lines (since is is a walkway, I needed railing textures there). Also, that wouldn't do anything to the lower texture, would it? I'd still need one...

If you make a sector self-referencing, you don't need lower sidedef textures. However, I guess you do lose display of the floor flat at that point and now I realize you want to see the floor. I've made such things (bridges with visible floors which you can walk under) using the zdoom sector transfer heights feature, but it's somewhat limited in the types of architecture where it'll work OK.

Anyway, about the extra textures you need, you can always place extra lines in a sector which can have main textures assigned and located by y offset. If you already have railings, just paste extra lines down right next to them, very close, and use the middle texture only on those new lines.

Basically I have no inner, self-refrencing sector, and don't intend to make one for that very reason (you'd be walking on air, it would seem). And this is a vanilla doom level... so I won't be using any zdoom features.

All may not be lost. To recreate the floor, sorta, you can place parallel lines close enough together, give them a texture something like steptop, and it'll pretty much appear as a floor. Look at one of Cyb's bridges in the Helm's Keep wad he did recently as an example. He used bridge objects, but I think you can also do this in a vanilla wad. To the best of my knowledge, you'll need the self-referencing sector so that you can eliminate lower sidedef textures and get no HOM.

If you don't want to do something like that, then the answer to your biggest question is "no".

To the less-important question, the problem may exist with doom or doom2.exe. Just not worth worrying about nowadays.

netnomad312 said:
What engines, what versions specifically will crash upon seeing or being in such a sector? I heard that only the really old ones have this problem, but I figure it'd be a good idea to know which ones, so I can put that in the text file under bugs (for the .000001% of people who DO use such an engine).

You should always test it... or ask someone to test it with whatever engines you might think it could crash. Note that if you're not already testing with Doom2 your map might already not be usable with it due to VPOs and whatnot. What you probably want to know about this WadAuthor message is if it's talking about Doom or about Doom and source mods. I mean, it could just be saying that Doom v1.2 could crash, or something.

What I heard one time is that only the earliest versions, like 1.2, would ever crash. Is that correct?

I've been playtesting in ZDoom ever since I added sprites to the wad a while back (in SP; I use Legacy for multiplayer). The only other engine I have is Doom95 (which I'm pretty damn sure is 1.9).

BTW, does anyone know how many lines you can see in such an area without getting a VPO in vanilla doom? I can't test this myself, because I have new sprites and running it in vanilla doom would crash it (and I'm not about to merge this wad with the IWAD). Would it matter if some of the lines had both main and below textures that you can see? (In other words, is it the number of lines or the number of sidedef textures displayed that causes a VPO?)

netnomad312 said:

I can't test this myself, because I have new sprites and running it in vanilla doom would crash it (and I'm not about to merge this wad with the IWAD).

Try:

deusf -app yourpwad.wad

That doesn't change your iwad, but just adds the necessary stuff from the iwad to the pwad. You shouldn't release the pwad with those sprites appended, of course.

netnomad312 said:

BTW, does anyone know how many lines you can see in such an area without getting a VPO in vanilla doom?

actually the vpo in doom/2.exe was not based on line (though it does have a visible sidedef limit of 512 I think) but with visible planes. The limit is 256 (I think), but this has nothing to do with sectors as is my understanding, in fact you can cause a vpo with two sectors if you really wanted.

Essentially doom merges floors and ceilings that have the same properties, so if you have any adjacent floors or ceilings with different heights, light levels or textures those count as individual planes. Furthermore, depending on where you view it from, the heights don't always matter, so if you have something like this (this is a side view):

   1      2      3
________      ______
        |____|

where 1 and 3 are diff sectors with the same properties and 2 is entirely different then if you view them for an angle where you can't see two at all (or any lower textures), doom will count 1 and 3 as the same visplane. so yeah, it's a fair bit of craziness, but I'm pretty sure the limit is 256 vps (if it's not that then it's 128).

netnomad312 said:
What I heard one time is that only the earliest versions, like 1.2, would ever crash. Is that correct?

That could be what WadAuthor means, as I doubt it'd be talking about anything else without specifying.

I've been playtesting in ZDoom ever since I added sprites to the wad a while back (in SP; I use Legacy for multiplayer). The only other engine I have is Doom95 (which I'm pretty damn sure is 1.9).

Doom95 is pretty much like the DOS engine but with a somewhat higher visplane threshold, and on rare circumstances it can fail or crash where the DOS version runs fine. What I think is that mappers should specify with what engines the maps were tested; it's a good guideline for users as they'll be able to decide what the maps might work with properly. A mapper may not be aware of a quirk here or there that might make the map incompatible with certain engine, and this applies even between limitless engines (even though some are very stong in covering the features of other engines.)

Oh, if you want Doom2 v1.9 for testing purposes and whatnot, get it from here (Doomworld) at the DOS section of the Source Ports page. The v1.9 engines are also at the site linked on my sig.

Dude, I think I might have the answer to your problem. What you might need is a fake 3D bridge. (Look under the tutorials section.) The problem is I'm not sure if it'll give you a HOM. Definately worth checkin' out, though.

(and I'm not about to merge this wad with the IWAD).

It really ain't a big deal. I've been merging into the IWAD for a while now so my new stuff will show up in DETH. Wintex makes it real easy.

EDIT: Whoops, you can't walk under 'em either, but it seems like you won't need to.

netnomad312 said:

Other, less important question: WadAuthor keeps telling me that some of the sectors I made will crash older game engines because their ceiling/floor differences are too high. What engines, what versions specifically will crash upon seeing or being in such a sector? I heard that only the really old ones have this problem, but I figure it'd be a good idea to know which ones, so I can put that in the text file under bugs (for the .000001% of people who DO use such an engine).

It's just v1.1 and v1.2 I think. Given that virtually no-one uses that version anymore (except perhaps those who don't have Ultimate DooM and don't know about the upgrade patches), you don't need to include it as a bug. (as there are tons of wads with huge pits etc. without mentioning it as a bug) The line limits are also lower in those versions, which is another reason why no-one uses them.

Personally, I think that the next release of WA should have that bug taken off the checker.

Cyb said:

actually the vpo in doom/2.exe was not based on line (though it does have a visible sidedef limit of 512 I think) but with visible planes. The limit is 256 (I think), but this has nothing to do with sectors as is my understanding, in fact you can cause a vpo with two sectors if you really wanted.

Essentially doom merges floors and ceilings that have the same properties, so if you have any adjacent floors or ceilings with different heights, light levels or textures those count as individual planes. Furthermore, depending on where you view it from, the heights don't always matter, so if you have something like this (this is a side view):

   1      2      3
________      ______
        |____|

where 1 and 3 are diff sectors with the same properties and 2 is entirely different then if you view them for an angle where you can't see two at all (or any lower textures), doom will count 1 and 3 as the same visplane. so yeah, it's a fair bit of craziness, but I'm pretty sure the limit is 256 vps (if it's not that then it's 128).

Actually, for such a large outdoor area the sector count is rather low... I have two major platform sectors (at different heights; and stair sectors connecting them) and one surrounding sector with sky flats. There is also a red-brick building that you can see into from the platforms (and will eventually get into at one point), and a few platforms that pop up with enemies.
This is a picture of the stairs connecting the two major platforms.
This is the red building.
This is a view from a certain high platform you'll reach at one point.

EDIT: Meh, damn Tripod linking policy! I'll put them all on a page or something later.

myk said:

That could be what WadAuthor means, as I doubt it'd be talking about anything else without specifying.

It specifically said "older wadgame engines."

myk said:

Doom95 is pretty much like the DOS engine but with a somewhat higher visplane threshold, and on rare circumstances it can fail or crash where the DOS version runs fine. What I think is that mappers should specify with what engines the maps were tested; it's a good guideline for users as they'll be able to decide what the maps might work with properly. A mapper may not be aware of a quirk here or there that might make the map incompatible with certain engine, and this applies even between limitless engines (even though some are very stong in covering the features of other engines.)

Oh, if you want Doom2 v1.9 for testing purposes and whatnot, get it from here (Doomworld) at the DOS section of the Source Ports page.
The v1.9 engines are also at the site linked on my sig.

I have the 1.9 exe... I have to at least have it to use DeHackEd. I never use it, though.