So, is Doom a raycaster?

Dear Maes,

Perhaps you could admit you are wrong for once instead of calling someone "butthurt" and pushing a thread in an insane direction with some nonsense question.

Or perhaps not?

Maes said:

Congratulations for the "sometimes ad-hominems are appropriate" comeback though. It's like saying "sometimes insulting is justified". And for someone who's just a few days on this forum, you sure were quick to make that judgement call. And with what aplomb! What resolution! What class! Like a boss! We certainly need more like you here.

Well, sorry for upsetting the status quo around here. I actually lurked on this board for many years before I signed up a few days ago to make these posts, and within that time I had actually grown to think of you as a very knowledgeable person when it comes to this stuff, so you can imagine my disappointment when I found out that that wasn't necessarily the case.

Anyway, it seems like your feelings are hurt quite a bit more than mine right now.

Maes said:

Well, since you seem to be an OK (?) fellow who's obviously been there and knows his shit, answer me this question which has been bugging me for a long time: what do you reply to a woman asking you if a certain item of clothing makes her look fat?

I usually just resort to being honest and saying I can't tell the difference. Not that it helps me to get out of shit better than anyone else of course.

EDIT: I also want to point out I'm not some kind of genius myself with this stuff, after I mentioned the Marathon engine was a raycaster yesterday I did a google search to confirm it and found that that may not actually be the case after all. Turns out that that discussion is at least as filled with hearsay as this one, only even fewer people know how that engine works so there are more people bopping around on development boards spreading all their misinformation like wildfire. So shame on me for taking their word for it. And it's very surprising to me that Catacomb 3D wasn't a raycaster like Wolf3D, too.

Point is, you can't always look at how something looks and guess which one of two algorithms put it on the screen. It's far more complicated than that.

TBQH, I don't care who's "right" and who's "wrong" here, and for all I know, we could both be a bit of both.

For me it's enough to know:

• Doom is definitively NOT a raycaster.
  
• Wolf3D is definitively a raycaster.
  
• Duke3D...could be, could not be, depending on who you ask, but it certainly was shit-slow compared to Doom, no doubt about that. That's why I made the "Am I fat?" woman question problem analogy: it's a question which has no correct answer, because each side has different assumptions.
  
• I guess we could debate other games like Ultima Underworld etc. but in the end, this debate makes as sense as "Is Metallica Metal?". It all boils down to semantics.
  

Only that I wouldn't go as far as insulting the other party for not agreeing with me on such a trivial matter, not even on an internet forum. But maybe that's just me.

FWIW, seems like the Build engine is not a raycaster, but some sort of brute-force wall sorter (this old thread got me confused...). But that simply would put it in the broad "doesn't use a pre-sorted world geometry structure" category I mentioned before, and that's good enough for me.

Well all things aside, I'm glad you have your question sorted out the way you like. Now the rest of us can get back to the topic at hand.

Marathon was indeed a portal based engine. Or "5D space" as the Mac-using hipsters at Bungie liked to call it. Though the walls never moved, they did take advantage of it by having overlapping rooms, sometimes simulating 3D space by not allowing their heights to intersect, or directly spitting on Euclid's grave by allowing their heights to intersect.


Other Doom-like terminology they arbitrarily redefined include:

Sector = Polygon
Demo = Film
Speedrunner = Vidmaster
Tic = Tick
Grid unit = World unit
Lift = Platform
Campaign = Scenario
Multiplayer = Netgame

There's more but I can't think of it right now.

Sodaholic said:

Though the walls never moved, they did take advantage of it by having overlapping rooms, sometimes simulating 3D space by not allowing their heights to intersect, or directly spitting on Euclid's grave by allowing their heights to intersect.

Ah yeah, that makes sense. I remember some kind of multiplayer (excuse me, "netgame") map from one of the Marathon games that used lots of tricks like that. It might have even been called 5D Space itself, but it's been long enough that I can't really recall for sure anymore.

sheridan said:

Ah yeah, that makes sense. I remember some kind of multiplayer (excuse me, "netgame") map from one of the Marathon games that used lots of tricks like that. It might have even been called 5D Space itself, but it's been long enough that I can't really recall for sure anymore.

It was indeed called '5D Space'. I've never played Marathon multiplayer, but I've looked through the maps. It was basically a grid/maze superimposed on top of another grid/maze, both exactly the same height and in the same position, but you could walk from one to the other.