Pondering on the potential that Doom is 2D and 3D simultaneously

[Koko Ricky]

I know, I know. There have been numerous, mostly pointless arguments on how many dimensions Doom has, and so the subject has become very eyeroll.gif. Despite this, I had a thought the other day I'd like to share.

 

If Doom's maps are constructed from 2D lines, and the renderer adds a limit Z-axis for height, then you have 2D map data and limited 3D rendering. It's both, simultaneously. If Doom's entities are 2D sprites, but have 3D hitboxes, then you have 2D objects with 3D collision. It's both, simultaneously.

 

Yes, there are sprites with infinite height checks, the renderer omits three-point perspective in favor of two, and complexity of 3D structures is uniquely limited; this doesn't change the fact that 3D calculations are required for certain aspects of the game to work. Ultimately, if we want to be as objective as possible--and this requires an agnostic approach to the legitimacy of a given dimension's characteristics--we must admit the game is both, working together to create a hybrid experience.  

[Ludi]

According to the devs, Doom is 1.5D. Sorry, it's not up for debate ;)

 

 

[Koko Ricky]

Well I guess I'm wrong! Close the thread ;-)

[banjiepixel]

Doom is literally a mix of 2D and 3D elements. I never understood why it must be black and white. Just think about the many modern fighting games. The game might be rendered in full polygonal 3D but the gameplay is still pretty much just as much 2D as the older sprite based games in the sae series. If we were to remake Doom into full polygonal game using modern engine while keeping all the original mechanics intact, it still would be both 2D and 3D simultaneusly. I would call Doom to be a "Limited 3D" game.

 

Just look at the (original) aiming mechanics, you can't look up or down and most of the time combat is pretty "flat" but sometimes the height of things does matter alot and the autoaim systen is put on some hard use. 3D is always there but in limited form to serve the more 2D focused gameplay. So basically 2D is the Dom and 3D the Sub in this relationship.

[Guff dotD]

4 minutes ago, banjiepixel said:

So basically 2D is the Dom and 3D the Sub in this relationship.

Perfect Analogy.

I will now use this phrase whenever someone from outside the community asks/argues if/whether Doom is 2D or 3D.

 

On topic, however: Doom is 3D, but limited due to processing power of mid-range computers at the time. Some calculations were simplified by treating actors as infinitely tall; however, projectiles still pass over them (if auto-aim happens not to work).* I bring this up because the 'infinitely tall monsters' dominates the zeitgeist surrounding the Doom Engine, and I want to point out exceptions.

 

*You can see this when you fire a projectile weapon at a high elevation, where a cliff has some blocking props (like in MAP09). The projectiles will carry on unaffected by the objects below.

 

[IIRC] I think that the limiting of the player's view to horizontal aiming was that Carmack (or the id team) thought that y-shearing (like in Heretic) was ugly, but I can't seem to remember the source, so take this with a grain of salt.

[Klear]

Moreover even modern "true 3D" games are just smoke and mirrors. In the end it's rapidly changing lights tricking your brain into seeing something meaningful. Calling something true 3D or not is a pretty arbitrary choice. It might be a useful distinction in some contexts, of course, but there is no deep truth to be found underneath.

[Edward850]

Why do these threads keep coming up? This has been discussed to death.

 

1 hour ago, Koko Ricky said:

If Doom's maps are constructed from 2D lines, and the renderer adds a limit Z-axis for height, then you have 2D map data and limited 3D rendering.

The renderer doesn't pull this information out of fucking magic, the height information is stored in the map, and it is information the lines have access to as they reference the sector information. Hell, the original DoomEd defined the height on the lines directly.

Also it objectively isn't information only the renderer uses, because:

 

43 minutes ago, Guff dotD said:

Some calculations were simplified by treating actors as infinitely tall

No actor is treated as infinitely tall, all actors always have height defined which is tested against geometry and various actor collisions. What's going on is solid actors (that is, two solid actors colliding with each other) are explicitly forbidden from crossing over each other, because there isn't enough information to handle knock-on collisions. This was fixed in heretic and Hexen (and Strife removed the restriction, but didn't fix it).

 

"Infinitely tall actors" is a ZDoom misnomer which is drastically not what is happening at all.

[magicsofa]

1 hour ago, Koko Ricky said:

If Doom's maps are constructed from 2D lines, and the renderer adds a limit Z-axis for height, then you have 2D map data and limited 3D rendering.

 

Just gotta nip this in the bud... map data includes Z information for floors, ceilings, and textures. 

[TasAcri]

1 hour ago, Guff dotD said:

Doom is 3D, but limited due to processing power of mid-range computers at the time.

 

This is the correct answer.

 

IMO DOOM is a 3D game that takes some shortcuts so the computers at the time can run it fast enough. It's a 3D game that tricks the computer to run it like it would a 2D game (or at least that's how i interpret it). The result is still a 3D game experience that has some 2D elements, though most people don't really notice them (other than the flat enemy sprites that is). Which means these shortcuts don't really undermine the game's 3D-ness, IMO.

 

However, i can still agree with the OP's premise that DOOM is a hybrid of 2D and 3D. This age old argument is simply people who focus on one aspect (3D or 2D) and ignore the other, after all. But the game does both really.

 

What i can't accept though is DOOM being a strictly 2D game. That simply won't do.

[Fiber Wire]

Wolfenstein 3D is junkyard scrap 3D, Doom is Honda Civic 3D, and Quake is Rolls-Royce Boat Tail 3D. 

[banjiepixel]

3 minutes ago, TasAcri said:

What i can't accept though is DOOM being a strictly 2D game. That simply won't do.

 

Wolfenstein 3D could be fairly argued to be strictly 2D game but not Doom. Wolf3D does basically nothing that basic 2D overhead shooter couldn't do outside of the camera angle.

 

And Doom started as one of the most 3D games in the market back in the day. It is literally just that games have become more 3D so Doom has become more 2D by more modern standards. But it is basically impossible it to become strictly 2D.

[Shepardus]

 

[Graf Zahl]

1 hour ago, Edward850 said:

"Infinitely tall actors" is a ZDoom misnomer which is drastically not what is happening at all.

 

Please suggest something better that also is understandable to laymen.

There's other options with far more atrocious naming because nobody came up with something as catchy for them as as "infinitely tall"

 

[inkoalawetrust]

I'm seconding Graf. Sure, "mobjs do actually have height information, but vertical collision in the original id Tech 1 engine is only applied for projectiles and items, not solid mobjs" is more accurate. But it's not only not as catchy, but requires Joe Average to actually know enough about Doom to get what that means in the first place, at which point they'd probably not be getting confused by this idiosyncrasy in the engine to begin with.

[Edward850]

12 minutes ago, Graf Zahl said:

 

Please suggest something better that also is understandable to laymen.

There's other options with far more atrocious naming because nobody came up with something as catchy for them as as "infinitely tall"

 

"Allow Standing On/Under Monsters" would be more correct and is laymen proof as it describes exactly what it enables.

[indigotyrian]

1 hour ago, Klear said:

Moreover even modern "true 3D" games are just smoke and mirrors. In the end it's rapidly changing lights tricking your brain into seeing something meaningful. Calling something true 3D or not is a pretty arbitrary choice. It might be a useful distinction in some contexts, of course, but there is no deep truth to be found underneath.

 

The advent of VR games have led VR gamers to refer to traditional screen games as "pancake games." Quake confirmed for 2.5D

[Murdoch]

Can we please stop beating this dead horse for the love of all things holy, unholy and in between? Actually at this point it's less a dead horse and more the bleached and broken bones of it's skeleton.

 

Doom IS 3D. If it is aware of a Z axis, it is by definition 3D. Just because there are limitations (no room over room, sprites for objects) or bugs in the implementation (infinitely tall actors) doesn't make it not 3D. Given Heretic and Hexen fixed the infinitely tall actors bug without major rewrites and projectiles can pass over and under other things plainly demonstrates not only that this was a bug and not an engine limitation but also shows once again that the engine has concepts of 3D space.

 

Doom is fundamentally 3D at it's core. The fact that it, say, renders a 2D sprite to represent an object doesn't make it not 3D. It positions and tracks that sprite in all three axis. Wolfenstein 3D, by contrast is 2D rendered as 3D. It has no concept of the Z axis.

 

But more to the point, why does it matter so much to beat this talking point into the ground once again? Why does it matter so much to people to pigeon hole things so precisely? It's kind of like the metal nerds who lose their shit when someone has the audacity to call band x thrash metal when they're actually death metal. You have contributed nothing new or interesting to this discussion @Koko Ricky, everyone knows and understands the points you have raised. I am struggling to understand what you are trying to accomplish with this thread at all. The geometry is 3D. You need to be aware of what's going on as a player on all 3 axis, just like the engine. It is not remotely a hybrid experience. If you think in 2D in Doom, you're going to die.

Edited March 23, 2023 by Murdoch

[Fiber Wire]

I feel the whole 2.5D thing started back when editing books were common. It was likely they didn’t know how to explain engine limitations any better for people trying to learn mapping with the editors of the time. So it was easier to say Doom wasn’t fully 3D to help explain why you couldn’t have rooms over rooms and the other limitations that could hinder people trying to make levels. It was an attempt to lower the expectations of people with impossible visions for map designs I assume, and people spread this by word of mouth regardless of if it was completely true or not. Just a guess, anyways. 

[Klear]

52 minutes ago, segfault said:

 

The advent of VR games have led VR gamers to refer to traditional screen games as "pancake games." Quake confirmed for 2.5D

 

Quake 1-3 can already be played in VR, Q4 is coming soon, so the series is safely 3D.

[Fiber Wire]

 Surprising you took what they said there seriously. That was definitely sarcasm..

[WSADKO]

Doom is 2.5D, one guy on reddit said so

[Xaser]

The "is Doom 2D or 3D?" topic is only 1D.

[heliumlamb]

In other words non-Petersen maps strictly depict ground Petersen maps occupy.

[Dusty_Rhodes]

6 hours ago, Klear said:

Moreover even modern "true 3D" games are just smoke and mirrors. In the end it's rapidly changing lights tricking your brain into seeing something meaningful. Calling something true 3D or not is a pretty arbitrary choice. It might be a useful distinction in some contexts, of course, but there is no deep truth to be found underneath.

The Treachery of Images remains relevant. Ceci n'est pas une pipe!

 

On topic: as other said, the map data contains the z - axis. The only thing 2D in Doom are the sprites, and even then they have collision boxes. I wish people would stop talking about this. 

[Peter]

9 minutes ago, Dusty_Rhodes said:

The only thing 2D in Doom are the sprites...

Not when they have a full set of rotations 😉

[Murdoch]

23 minutes ago, Peter said:

Not when they have a full set of rotations 😉

 

The engine is essentially doing the equivalent of taking a cardboard tube and sticking a cut out of a monster on it. It's using 2D information to present what is actually a 3D object (albeit primitive).

[SleepyVelvet]

I'd compare it to a game like Descent, which had all of X, Y, Z, Pitch, Roll, and Yaw, therefore making it a 6D game.  Doom only has X, Y, Z, and Yaw, so therefore it is only a measly 4D game, sadly.

[StarTanned]

From a gameplay perspective, to me about the only thing that's "more 2d" about classic Doom compared to modern shooters is the infinitely tall monsters, and it's not like gzdoom and other ports don't let you remove that immersion-breaker if it really bugs you. I so rarely find myself having to take 3d spaces into account in any more meaningful way in modern shooters compared to Doom. And from a visual perspective... I can't care less anymore. It all hits the uncanny valley for me once I stop looking at screenshots and cutscenes and begin playing the game. They pretty much all boil down to "classic Doom with gimmicks" to me in the end (and I'm not complaining about that).

[Mr. Freeze]

Doomkid punching air rn at this thread

[Azuris]

2 hours ago, NoisyVelvet said:

, Roll, and Yaw, therefore making it a 6D game. 

 

This is not how the Term Dimensions works :P

 

Also, every X,5D Term is stupid.

Something is 3D or it isn't, only because it uses Sprites or you only move right and left, doesn't mean that it hasn't X,Y and Z.

 

Doom is 3D.

Engine Limitations and Sprites doesn't change it.