
The Doom Movement Bible - rinesh
https://www.doomworld.com/vb/post/1586811
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nailer
As a DOOM modder a couple of notable things:

1\. DOOM had wall running (by accident):

> So in other words, when the player is moving northwards or eastwards with a
> XTAP / YTAP greater than 15, and has the initial movement check blocked by
> something, the engine has the potential to perform _two full movements_ in a
> single tic! Note that this doesn’t actually change the TAP or anything -
> it’s just as if the player moves two tics’ worth of movement in a single
> tic.

2\. DOOM also had deliberate rocket falls - like a rocket jump except you'd do
it against a cliff and fall further away from the cliff as a result. This was
used to clear a wall needed to get to the Episode 3 secret mission.

I hope, somewhere in DOOM 2016 single player, I turn a corner and see an up to
date but recognisable E1M1.

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haddr
This is just amazing. And what is more suprising is that Doom 1 and 2 are
still thriving after >20 years. If you download zandronum you will learn that
there are still people playing it online. of course those are some mods, but
still very much resembling the original atmosphere and graphics of doom 1 and
2.

Edit: of course this probably would be different if the doom source code
wasn't released at some point of time...

~~~
zanny
Yet for some reason _extremely_ few games have followed id's example. Besides
Duke 3d, what other games ever saw source release?

~~~
newobj
NOLF: [https://github.com/osgcc/no-one-lives-
forever](https://github.com/osgcc/no-one-lives-forever)

~~~
justinlardinois
That's really cool. Kotaku ran an article <a year ago about the licensing
issues around No One Lives Forever and how it would probably never make it to
Steam; I'm surprised they never mentioned that the source code has been
available for 4 years, buildable by anyone.

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kodisha
If you are interested what was pinnacle and end result of this, take a look at
CPMA/PQL movement in quake

Thats basically strafe jumping with air control:

[https://www.youtube.com/watch?v=p_DwN4z5UMo](https://www.youtube.com/watch?v=p_DwN4z5UMo)

[https://www.youtube.com/watch?v=lANjZ0NO8XI](https://www.youtube.com/watch?v=lANjZ0NO8XI)

and some examples with fights:
[https://www.youtube.com/watch?v=mHo4l-qmGHI](https://www.youtube.com/watch?v=mHo4l-qmGHI)

This was by far the most hard to master, and most rewarding skill, once you
can do laps around the maps you lost track of time, and find your self doing
this for hours.

[https://www.youtube.com/watch?v=-T6IAHWMd2I](https://www.youtube.com/watch?v=-T6IAHWMd2I)

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pimlottc
Wow, really fascinating and excellently explained! I can't help but wonder,
how many of these were found solely through play and how many were found as a
result of code diving? The conditions to trigger some of the, such as void
skip, seem so intricate as to be unlikely to be found by chance.

~~~
linguica
Doom has been played for probably thousands of man-centuries at this point so
all of them had been found through normal play. However, a lot of them had no
real documentation explaining why they happened, since speedrunners tend to
view bugs from a "how can this help me?" mindset rather than "why does this
occur?" The elastic collisions bug in particular was considered a mystery
before I researched it, but the rest were more or less understood.

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axx
More or less off topic, but what is the best way to play DOOM on a modern Mac
or PC? I have the CD of The Ultimate DOOM.

The same could be asked for Quake 1 & 2 :)

~~~
40281889
I'd say look into two different source ports: namely, ZDoom and GZDoom.

ZDoom is one of the most popular source ports capable of running all WADs and
it's still being maintained. GZDoom is the OpenGL supported version of ZDoom
with new scripting capabilities and GL lights.

For Quake 1 there's the DarkPlaces source port, and for Quake 2 there's Yamagi
or Q2PRO.

~~~
moonfern
(G)Zdoom can play all wads made for other ports but it's not backwards
compatible with wads made for older version of zdoom. And that's a pity
besides you have to change many default options to play "doom" like it was. In
original doom monsters have infinite height, so you can't walk on
monsters,pass under flying monsters. Looking up/down, jumping and making the
bfg more powerfull are other changes. Great mods, wads and even indie games
have been made with g/zdoom but the topic is the original doom movement. In
that context people use mostly prboom + or chocolate doom.

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deathanatos
I tried the item-grab-through-a-solid-linedef trick in Zandronum on E4M1 (the
same one as in the video on the post), but couldn't get it to work. Tried
fudging around with the compatibility options (including "Doom" and "Doom
(strict)") but still no dice.

Strafe-running definitely works though, and it's a trick I've used for some
time, even in multiplayer.

(Also, if you're curious that Doom is still around, I highly recommend
Zandronum[1]. An excellent port. And there are still mods coming out that are
incredibly playable, which blows my mind.)

[1]: [https://zandronum.com/](https://zandronum.com/)

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orliesaurus
this hit me right in the feels, shame that doom4 feels like a console port

~~~
oxide
I found the multiplayer of the new DOOM to be full of strange design
decisions.

It clearly wants to be an arena shooter, but it couldn't let go of loadouts
from Call of Duty, nor the "modern" Halo roots the team had previously worked
on. (see: Call of Duty)

The result is an amalgamation of everything wrong with modern multiplayer
shooters, distilled through a DOOM filter and collected in a toilet. It wants
rocket launchers, but it kills in two shots instead of one because you can
just spawn with one.

It's a damn shame. Instead, I decided to go play the Unreal Tournament alpha.

~~~
orliesaurus
Doom4 loadout system is really sad. The powerup mechanic is cool but minimally
useful, the Revenant is just extremely unbalanced: He can fly, kill instantly
and has 3x more HP than a normal player. If you get to play Doom4 multiplayer
s with friends, all you need to do is camp the spawn (which is easy because
its spawn is announced way ahead of time)

Unreal Tournament alpha is not much better, the netcode is weird, the new
movements are extremely buggy and the weapons are unbalanced. The only good
thing about UTalpha is that they stick to the original vision: Fast paced,
aim-skill game, with very little novelty (other than movements and like one
weapon's behaviour has changed)

I am looking forward to overwatch, although its not a real FPS, at least I
feel like Blizzard cares about the game they push out and are not blindly
following trends.

I been playing UT since early 2000s when i was just a kid and I feel sad that
so little importance has been given to this title. I wasn't expecting Doom to
be another QuakeLive, but at the same time not another "CoD12: Future Ops from
Hell - Mom get the camera edition"

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jheriko
> This sort of discrete movement is probably universal in games

if only... :P

i've certainly lost a lot of time to resolving collisions by considering the
inbetween steps, using lines, fat lines and all sorts...

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busterarm
I haven't been a regular around Doomworld in a long time, but it amazes me how
this site just keeps on going.

Seriously one of the best online communities ever.

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Kenji
I am so happy to see that even the creations of the genius Carmack are full to
the brim with 'ugly' hacks, workarounds and tweaks.

~~~
AceJohnny2
Carmack wasn't the only one working on the code. But yeah, once the bugs are
highlighted here, they're pretty glaring. Hindsight and all that... ;)

