Two floors on same position in some map. How is it possible ?

[Tigrou]

Hi there,

I was playing City Assault map from Sergeant_Mark_IV lately (which is by the way an excellent map), and one thing amaze me.

This is at the end of the level. Here :






You have basically two floors at the same place (and no glitches). It does not seems to be sprites.

How is it possible ?

AFAIK, this is one of the biggest limitation of the DOOM engine. I know that gzdoom/zdoom (that i use) isn't actually the exact DOOM engine (like Chocolate), but rather an improvement.
Is it something like room over room feature like in Build engine ?

[Obsidian]

I see you've discovered the joy of 3D floors! ZDoom shows them to some extent, but GZDoom is definitely the port to use for 3D floors in all their glory. If you want to learn how to make them, here is a tutorial by ChubzDoomer.

[Springy]

I believe it is a room over room feature. Vanilla can do a similar thing though only for cosmetic purposes as far as I know. I think that actual room over room like what is shown in that example, can only be done in ZDoom I am not sure if Boom extended upon the original vanilla technique or not. Well, Obsidian hit the nail on the head better than I did but I can definitely second Chubz Doomer's tutorials as they cover a lot of things in depth.

[Tigrou]

Thanks both you guys. "3D floors", this is the name. It seems they even implemented slopes. I'm impressed to discover how far it things have been pushed.

[scifista42]

ZDoom engine specializes in coming up with new features. Slopes, 3D floors, ACS/DECORATE scripts (see the linked wiki) are just a couple of them. Other ports stay more loyal to the original Doom executable (Chocolate Doom port), or are somewhere in the middle of the way (Boom and Boom-compatibility ports). Those lower ports can't use 3D floors and other ZDoom specific features, though. In your case, the mod was designed specially for ZDoom-based engines. It really depends on what port and what mods you choose and how faithfully-original Doom you want to play. ;)

[Gez]

http://doomwiki.org/wiki/Room-over-room

[hawkwind]

Obsidian said:

I see you've discovered the joy of 3D floors! ZDoom shows them to some extent, but GZDoom is definitely the port to use for 3D floors in all their glory.

... and let's not forget Risen3D. It's use of 3D floors is also glorious.

[Maes]

There's also the infamous cDoom, a DOS port very close to Boom (and arguably, 100% vanilla compatible) which features its own flavour of Room-over-Room, though admittedly it's difficult to fully appreciate it in 320 x 200 VGA resolution. It also looks glitchy when combined with sprites or multiple overlaps.

[Zed]

According to the wiki, 3D floors are possible in CDoom, Legacy, EDGE, ReMooD, Skulltag & Vavoom, besides the ones already mentioned.

Just a quick question: 3D floors refers to Room-over-room? I mean, are they both exactly the same thing?

Also, I think GZDoom supports slopped 3D floors. Are there other ports that can do this?

[Gez]

Zed said:

Just a quick question: 3D floors refers to Room-over-room? I mean, are they both exactly the same thing?

No. As the wiki article I linked to says, 3D floors are one way to get room-over-room; but it's not the only way. Portals, for example, are another way that gives convincing visuals without trickery.

(Actually, the 3D floor in ZDoom is handled by the renderer as if it were a portal effect. That's why they have to be purely horizontal. GZDoom, on the other hand, renders them as actual polygonal 3D floors which is why they can be sloped.)