Game Theorists "Doom Wasn't 3D" video and my refutation

Kb1 what kind of hill are you trying to die on here? Is your goal only to be contrarian? You have your own port that I've seen and played with my own eyes, you know doom has the z-axis specifically denoted in its code. Wtf nonsense are you saying with these unrelated, halfassed points when the real knowledge you do know suffices and is actually correct?

9 hours ago, Graf Zahl said:

Sorry but that doesn't fly. Although you can play Doom from the automap it doesn't render a fully representative view of the game, you cannot see where stairs, doors, lifts or other interactive elements are, where dropoffs are which block progression and such. So you will inevitably run into obstacles because the 2D view cannot represent them.

 

 

What if there was a 2D view with enhanced depth, direction etc. visual aids? Many top-down shooters from the 80s and the 90s did feature elements such as jumps over platforms, jumping over enemy projectiles etc. and even going up/down stairs, and the only clue as to where you could go was the artwork itself, usually with a so-called "isometric" or other kinds of creative, pseudo-3D views.

 

With a purely top-down perspective, still you could somehow give the player visual aids as to where is "down" and where is "up", clearly mark doors etc. but that goes way beyond the scope of the automap, even textured ones. It probably would require giving the player quite a lot of "spoilers" regarding the layout of the level, as well.

em... since when isometric projection becomes "pseudo-3d"?

Depends on whether you're talking about aesthetics (in which case it is, as it resembles orthographic projection), versus literal dimensionality (in which case it definitely is not).

oh, sure, any 3d->2d projection is 2d, of course. maybe i read it wrong too -- this thread becomes harder and harder to decipher.

What I find most interesting is that Doom's 3D hackery wasn't unique. There are a ton of shooters from that period that all relied on making height maps out of 2D geometric data, the difference being that Doom was faster, bigger in scope and more stable than its contemporaries.

13 hours ago, Maes said:

What if there was a 2D view with enhanced depth, direction etc. visual aids? Many top-down shooters from the 80s and the 90s did feature elements such as jumps over platforms, jumping over enemy projectiles etc. and even going up/down stairs, and the only clue as to where you could go was the artwork itself, usually with a so-called "isometric" or other kinds of creative, pseudo-3D views.

 

If you want to be technical, a lot of polygonal 3D games could be represented in top-down 2D without too much of an issue, even using a layered system for things like different floors like games like Zelda Link to the Past did. It would still be very much in a compromised state, especially since projectiles also use 3D collision, the only thing to not use infinite height actors in vanilla presumably because giving everything a third axis in collision detection would've been too much for CPU's at the time.

On 7/12/2019 at 2:32 AM, Graf Zahl said:

Nobody was ever disputing that Wolf3D and Doom were rendering their game view in 3D, denying that is utterly preposterous.

I claim that that is all you need for a game to be called a 3D game. *Especially* in 1993, when having a beautiful, full-screen, fully-colored and shaded, texture-mapped 3D first-person view was flat-out amazing.

 

To me, it's like saying "It's not a real song without a guitar solo..." Well, ok, bad example :) You're not a bass player if you're not using a 6-string bass? It's not dinner unless it's a 4-course meal with wine and dessert?

 

I don't need to see a dog smile to know he's happy, and I don't need to study any game mechanics to tell if it's a 3D game... I can literally see so.

 

 

On 7/12/2019 at 2:32 AM, Graf Zahl said:

The question has always been whether the game mechanics are 3D and that's an entirely different story I won't repeat.

Eh, I gotta call BS on that. Sure, maybe today. But, in '93, the renderer was the main event that left everyone's jaw on the floor. The game mechanics? I was in love before I realized that I couldn't look down. Hell, I don't know how long it took to realize that I was being scratched from 50 feet below. I was too busy wishing I had figured out how to draw such seamless, gorgeous 320x200x8 glory. You were too, don't be ashamed - everyone was :p

 

 

The question is implied the thread title: Doomkid is refuting The Game Theorist's "Doom Wasn't 3D!" video, and I am supporting Doomkid's position.

 

Actually, I feel that the video (the original, not Doomkid's) was a bit disingenuous, and lacked respect for the game that made it all happen. They're shit-talking our precious - hee hee. Who do they think they are?

 

Yes, of course the game mechanics are completely important. But id Software didn't rule the gaming world by typing:

 

// not literal code, folks
if (fireball_floor > monster_floor + monster_height &&
   fireball_floor + fireball_height < ceiling)

They took the world by storm because the game visually immersed everyone who looked at it into a compelling, simulated reality with width, depth, and height.

 

On 7/12/2019 at 2:32 AM, Graf Zahl said:

Sorry but that doesn't fly.

Of course it doesn't fly - I was being facetious. Playing with the automap view is soon boring, because it the 3D view that makes it awesome, not the height calculations. And that's true for Wolf3D too.

 

<joke> Of course it doesn't fly - that would require proper 3D mechanics. ;}  I had to. </joke>

 

On 7/12/2019 at 2:32 AM, Graf Zahl said:

Good try evading the issue 

Evading? I wasn't really gelling with the analogy, so I made a lame joke.

 

All in all, I'm not big on this "2.5-D" silliness. Hey, I never thought Pac-Man really looked like a guy eating cookies either... But, it looked great.

 

These armchair "game theorists" need to leave Doom alone!

 

 

17 hours ago, Fonze said:

Kb1 what kind of hill are you trying to die on here? Is your goal only to be contrarian? You have your own port that I've seen and played with my own eyes, you know doom has the z-axis specifically denoted in its code. Wtf nonsense are you saying with these unrelated, halfassed points when the real knowledge you do know suffices and is actually correct?

 

Yeah, I'm a twisted bastard, I guess... No hill required, nothing that fancy. Not even a fall...I think a slow slump over a dead log will suffice (maple or so, none of this pine shit...a little respect...)  I mean, I'm a man - I'll let out an "Ugh, good bye, I guess" before flopping over, half-raspberry, wondering how I was so misunderstood :(

 

Heh! You know what? I can't tell if I got dissed, acknowledged, praised, kicked? I think kicked is easier to accept...

 

 

 

So we have the holographic principle applied to Doom. That is, the description of the Doom-space can be thought of as encoded on a two-dimensional boundary to the region. This boundary in fact being the surface of a torus.

 

In that case, Doom would have three dimensions in much the same way that the universe has four space-time dimensions.

A good way to think of Doom's levels is the intersection/extrusion of two surface plots. If you think about it, a single surface plot defines a 3D surface (let's call it "floor"), and another one (enveloping the first) could be called "ceiling". Very few people would argue that surface plots aren't truly 3D, even though they aren't as flexible as e.g. a bunch of 3D points with totally free XYZ coords.

 

Well, on top of that, Doom's actors actually do have XYZ movement freedom. However, they are constrained in how and when they can change their Z-axis. Much like an airplane and a helicopter can both fly, but in a plane you cannot really control your Z-position independently of the other other two, or of your speed, for that matter (unless you're falling out of the sky...)

18 hours ago, Maes said:

Well, on top of that, Doom's actors actually do have XYZ movement freedom. However, they are constrained in how and when they can change their Z-axis. Much like an airplane and a helicopter can both fly, but in a plane you cannot really control your Z-position independently of the other other two, or of your speed, for that matter (unless you're falling out of the sky...)

Exactly! We, as humans, don't naturally fly, yet we still describe our surroundings as 3-dimensional. Likewise, Doom portrays a subset of 3-dimensional possibilities, and yet is a 3D game. It's not complicated.

 

@Grazza (holographic principle)

A fascinating read! (And way above my head) I fear we are learning things nowadays faster than we mature as a species. We live in amazing times!

Edited July 16, 2019 by kb1

On 7/13/2019 at 12:45 PM, kb1 said:

I claim that that is all you need for a game to be called a 3D game. *Especially* in 1993, when having a beautiful, full-screen, fully-colored and shaded, texture-mapped 3D first-person view was flat-out amazing.

 

It entirely depends on what you want to discuss. And since the originally linked video went to great lengths to disprove Doom's 3D-ness by (incorrectly) pointing to a 2D playsim, we should at least be able to name a game that actually does fit this description (i.e. something that's working entirely with 2D mechanics, but i rendered in a 3D view.) and explain why it fits the description. Aside from visual presentation, Wolf3D had zero concept of height, and even in the visual presentation, height was merely a constant.

 

I also tend to disagree with you here. Even back in 1993 it was painfully obvious to me that the game was utterly flat - the 'only' innovation was to render a run-of-the-mill maze game from the player's POV. (You may gather from this description that it also was a game that never caught my interest.)

 

 

 

 

 

 

15 minutes ago, Graf Zahl said:

the 'only' innovation was to render a run-of-the-mill maze game from the player's POV.

which wasn't something new too -- several RPGs already did it (EOB, Uukrul, and others). what was mind-blowing is real-time 3d rendering of a maze, with arbitrary yaw angle.

On 7/16/2019 at 3:11 AM, Graf Zahl said:

 

It entirely depends on what you want to discuss. And since the originally linked video went to great lengths to disprove Doom's 3D-ness by (incorrectly) pointing to a 2D playsim, we should at least be able to name a game that actually does fit this description (i.e. something that's working entirely with 2D mechanics, but i rendered in a 3D view.) and explain why it fits the description. Aside from visual presentation, Wolf3D had zero concept of height, and even in the visual presentation, height was merely a constant.

 

I also tend to disagree with you here. Even back in 1993 it was painfully obvious to me that the game was utterly flat - the 'only' innovation was to render a run-of-the-mill maze game from the player's POV. (You may gather from this description that it also was a game that never caught my interest.)

Yeah, I'll admit that I kinda forgot about Wolf when I saw Doom, which is sad, cause Wolf is kinda neat. I was a necessary step before Doom, and, it a lot of ways, more difficult to code. Wolf used 32-bit memory, but was written in 16-bit segmented mode (ugh!), meaning that it was a monster achievement. And, it threw out tons of frames per second...on a 386, no easy feat.

 

But, most of all, it drew clipped sprites over textured wall strips, scaled by distance - that's the definition of a 3D renderer. When describing older games, the following terms come to mind:

 

side-scroller, parallax scroller, platform scroller, top-down scroller, 2D space shooter, etc. These definitions are all about the rendering going on. You can see the game for 10 seconds and know what to call it. Same goes for Wolf, and Doom: 3D shooters. When you have war vets calling you up saying that your game helped them with their PTSD, you have a 3D shooter on your hands.

 

Many games have that one special thing - that gimmick that makes it what it is. Of course, for Wolf, it's the renderer - that *is* the mechanic of the game.

 

I guess we'll have to disagree, it just seems so obvious to me.

People who call Doom 2D or 2.5D don't understand what spatial dimensions are.

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Edited June 7, 2023 by QuotePilgrim

the imp projectile calculates a speed in the x/y plane and then adds enough z velocity to make it reach the correct Z height once it reaches the correct XY position. It has a full 3D position and velocity vector. You can literally do this in any 3D game engine. I could go do it in UE4 right now, and no one questions that UE4 is a 3D engine?

 

Likewise, steps are also a bit of a bad example. In games like Quake, where we're not questioning their 3D engine status, stairs also instantly change your Z height. Ramps don't, since the physics are more involved, but stairs have absolutely no effect on your XY plane velocity and you traverse them instantly. I'm less familiar with what more modern game engines tend to do here.

Edited December 2, 2020 by SaladBadger

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Edited June 7, 2023 by QuotePilgrim

That sure is a lot of words. Either something is 3D or it isn't. Stop trying to overthink it. 

my way of looking at it is, any game is going to have approximations. In a game where motion is typically constrained to the XY plane, with much less control over the Z axis, approximations favoring the XY plane are going to be more common. We have things like Quake's reality bending steps, in a game with otherwise very rigorous 3D physics. I am fully aware you mentioned that this doesn't make the game not a 3D engine, but I also don't really understand the intention here, at least why it's important enough to bump a 2 year old thread over it ^{I mean it's important to understand from a gameplay perspective at least}

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Edited June 7, 2023 by QuotePilgrim

Okay, sure, at a conceptual level, we can argue that the projectile has no Z velocity. it's not relevant for gameplay purposes how it's implemented, but that it exists somehow. (even then, though, an implementation not considering Z velocity would require a lot more work to simulate) But at an implementation level, this simply isn't true. The same code that makes an imp fireball soar through the air is the same code that makes the player (or dead monster) fall off a cliff, or a player or monster blasted by an archvile soar into the air. All of these interactions involve proper Z velocity, and the projectile indeed has Z velocity, just calculated differently than how, say, Quake would calculate it.

2 minutes ago, SaladBadger said:

Okay, sure, at a conceptual level, we can argue that the projectile has no Z velocity

Sure, on a conceptual level, however for Doom it's irrelevant as Z does have an explicit velocity: https://github.com/chocolate-doom/chocolate-doom/blob/master/src/doom/p_mobj.h#L238

Which projectiles do use for Z targeting: https://github.com/chocolate-doom/chocolate-doom/blob/b9416dc6f9e569adcd067c9acd0b18e5d3240dd8/src/doom/p_mobj.c#L1004

I mean, I did point that out in my post, but having the actual code links is helpful.

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Edited June 7, 2023 by QuotePilgrim

17 minutes ago, SaladBadger said:

I mean, I did point that out in my post, but having the actual code links is helpful.

Ah, so you did. That's what I get for being distracted. :V

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Edited June 7, 2023 by QuotePilgrim

Why does any of this matter again? Even if Doom isn't "troo 3D", it still gives the illusion of being 3D to the point where you don't question it while playing the game. What's so fun about arguing semantics? Why debate something if the answer doesn't make a difference in the end? If we find out that all this time Doom is a 2D game, what difference would that make? Is it going to lead to some major modding revolution or something? Is there any real enlightenment to be found in this debate? It's obvious after over 230 replies nobody is going to concede their point of view anyway.

Edited December 2, 2020 by TheMagicMushroomMan

At the end of the day dimension is just a term we drooling simians invented to be able to talk about space, coordinates, distances, and stuff like that with measurability. You will never be able to observe a 2D in nature or even a 3D in nature because it's not a thing. This is why it's wholly inappropriate to say somebody is stupid if they doubt Doom is 3D. "I doubt Doom is 3D" is not a claim about what Doom is, it's a claim about what 3D is. This should, in fact, be more than obvious.

48 minutes ago, QuotePilgrim said:

https://github.com/chocolate-doom/chocolate-doom/blob/b9416dc6f9e569adcd067c9acd0b18e5d3240dd8/src/doom/p_mobj.c#L998

Correct me if I'm wrong, but that line indicates the engine only takes the x and y axes into consideration when calculating distances, right?

Only if you read exactly one line in a vacuum. Read 6 lines down: https://github.com/chocolate-doom/chocolate-doom/blob/b9416dc6f9e569adcd067c9acd0b18e5d3240dd8/src/doom/p_mobj.c#L1004

th->momz = (dest->z - source->z) / dist;