Is it possible to stack sectors?

[Hoshasei]

I know that question might sound kind of vague but what i'm looking for is a method to make levels in a vertical fashion. but it doesn't seems like doom wants to let you have multiple floors. Looking through the cannon level maps it doesn't seem like any of them do it.

[Vermil]

Correct. In the original Doom you can only have one floor and ceiling in an area. Doom is not true 3D.

Some source ports have added 3d floors and/or portals however, that allow one to have room above room even though they still aren't proper 3D in the real sense.

[printz]

Yes, 3d floors or linked (not any kind of) portals are the way to go.

[bgraybr]

Heh. Before I discovered Doom forums I saw floating structures in a few GZdoom maps and some old hacky megawads. I almost exploded my 'lil brain trying to figure out how to stack sectors in Doom Builder. :D

[Alphawolf]

False floor markers.
Teleport destinations and extra sectors for the sector that is apparently 'above' the next sector

For instance a staircase at a certain height you get teleported to a new sector with still being able to see the other sector below, the same for above, you can simply add the eyes above fake floor markers for the teleport sector destination.

[Thamuzzz]

LOL im the master at this, i could show u a pic of somthing i made, but doomworld wont let me post pics for some reason??? :O

[Thamuzzz]

i can do real solid 3d floors, like bridges and stuff and have made some impressive interior designs that i want to show u. I can do all that, but i dont know how to post pictures on this :L how do i post a picture?

[Death Egg]

Upload the picture to a site like Imageshack, then put it in a post with [img] tags in front and behind. (The second must have a / before the i)

[Thamuzzz]

Do i just post a link of the picture shown on imageshack after?

[Thamuzzz]

http://imageshack.us/photo/my-images/402/3dfloorpic2.png/

http://imageshack.us/photo/my-images/706/3dfloorspic1.png/

umm i think thats it :S try those 2 links, let me know if it works

[Death Egg]

Yeah, the pics show up fine.

[cyberknight]

The engine wasn`t built to be able to make tower-like levels, or room-over-room architecture for that matter. It`s not that the tech used to make the Doom engine is incapable of loading multiple stories. It`s for the sake of the automap. But I`m sure there`s a patch that CAN do ROR architecture.

[Gez]

cyberknight said:

It`s not that the tech used to make the Doom engine is incapable of loading multiple stories. It`s for the sake of the automap.

Yes it is because the engine is incapable of handling them. No, the automap isn't an excuse.

The Doom engine is in 2D with elevation, often referred to by "2.5D" instead of 3D. Example: a cacodemon is flying 1024 units above you. Can you pass right under it? Answer: no, you're blocked. You collide with it if you try. Other example: a bunch of imps is crowding at the bottom of a deep chasm. Can you jump down? Answer: no, you're blocked. You collide with the imps if you try.

Everything in the engine works on X and Y coordinates only; with Z coordinates tacked on as an afterthought. Did you know that projectiles shot upwards or downwards go faster than if they're thrown straight ahead? The horizontal speed is always the same; autoaiming up or down is done by adding a vertical component to the velocity in addition.

Now that's for the world simulation part, which is hopelessly 2D but which can be modified. Boom, ZDoom and many other ports feature enhanced 3D-ness, generally as options. But there's the renderer to figure in too!

It turns out that the engine is only able to handle one floor and one ceiling. Drawing several floors and/or several ceilings is not possible. Boom added some tricks to allow changing which floor and which ceiling are rendered, permitting to give some illusion of multiple floors (i.e., deepwater effect); but it's still only one floor and one ceiling, no more, and it's easy to glitch up.

Until recently, Legacy was the only port with software rendering of 3D floors. This was coded by SoM, who could tell you about the problems he met when implementing that and the reason why Eternity, on which he works now, uses portals instead of Legacy-like 3D floors.

ZDoom now features software rendering of 3D floors (though it's more limited than in GZDoom's OpenGL renderer) but it has necessitated an important code overhaul.

By the way, the automap handles 3D floors fine if you are smart about it. Download an SVN build of GZDoom and load some 3D-floor-heavy map in it (Enjay's BGPA mod, or Eriance's DE, or Paranoid all have good examples). Look at the automap. Turn automap textures on for a more obvious effect. Now move up and down; say in a staircase joining two or more different floors; and notice what happens. :)

[hex11]

Descent had a nice 3D automap. :)

Anyway, with Doom you can get nice results without even any special ports or even vanilla engine tricks. For example, the Dark Covenant author did a great job on MAP03 and MAP07 in conveying a sense of verticality when playing those levels, even though it's just regular old Doom sectors.

[zZaRDoZz]

While it probably wouldn't be terribly useful, I'd love to read a comprehensive write up on the different methods doom and other 2.5D games use to emulate multiple floors. One can't help but notice the many different terms used for what appear to be similar map features:

Floor over Floor, Room over Room, Inverted planes, and 3D Floors all deal with vertical geometry of some form or another. I'm aware that a few of these are probably different terms for the same techniques, it's still hard to be sure for us non level designers though.