PrBoom+'s Compatibility Levels Explained

[@Dwars]

Some fun facts: In addition to all the other named complevels, you can use -complevel vanilla which will automatically detect which IWAD you've loaded. Another source port, Woof!, can use a lot of these parameters as well, especially for all the important complevels (including -complevel vanilla) as well as full support for the new MBF21 complevel.

[@ikagura]

Nice to know

[@AlexeiVoronin]

Wow, what a nerd :P

[@sunfl0wer_988]

Woof, what a nerd AND a furry.

[@majamystic256]

i think Woof and DSDA Doom are the only 2 ports that support MBF21 right now

[@plazmasyt]

@@majamystic256 There are a couple more that I know of, FDWL and Pooch.

[@Baryshnikov4804]

16:48 "and special thanks to agonizing rectal pain" gets me every time

[@iguana9173]

That makes me laugh too.

[@evilotis01]

also: "hnnnnnnggggghhh!!!"

[@matt.604]

@@evilotis01 That's what agonizing rectal pain sounded like.

[@MateDrinker33]

@@iguana9173 I think he might be the same person as "Vladimir Jerkov" (appears in virtually all patron credit rolls to analysis videos published prior to "Why Can Mancubus Fireballs Go Through Walls?").

[@AB0BA_69]

@@evilotis01 CappaBitch is my favorite. I'm just glad Decino is a good sport about these joke/troll/meme names and says them out loud. Cheers, bud!

[@dinitroacetylen]

A Team TNT engine that breaks a Team TNT classic map. Well, that makes lots of sense.

[@MrTomas7777]

"Bug is a feature" situation

[@dinitroacetylen]

@@MrTomas7777 the other way around, though.

[@MrTomas7777]

​@@dinitroacetylen It's both, I suppose. The stairs bug was like a feature. "Fixing" it introduces a bug.

[@hus80sam]

"Use GZDoom like a normal human being " - Decino =-2021

[@nekrovulpes]

Doomworld is probably having a meltdown about this.

[@vatsalmamgain5069]

*angry Purist noises*

[@emekoo1027]

I always heard "cheesydoom" instead GZdoom! 😂

[@blarno]

Is right. GZDoom 4 life.

[@CaveyMoth]

I really prefer regular ZDoom, for some reason. XP

[@Lemon_Inspector]

I like the idea that the existence of demos essentially forces the Doom community to keep bugs forever. It would be interesting to take the source code of the PrBoom engine and color-code it according to the compatibility level it handles, to see all the clutter.

[@KopperNeoman]

It's just like Worms Armageddon (and Halo games with replays) - older versions are supported. Best seen in Halo 4; old replays won't have the X when your teammates are dead.

[@JoeyJoJoJoestarJuniorShabadoo]

I remember lost souls spawning out of bounds was a fairly common thing way back when playing on my old 486. I was wondering why it never seems to happen in doomtuber videos, now I know it's been fixed in source ports.

[@horst_gott]

I am still hearing those monster growls through the walls after all those years. And I still occasionally avoid killing pain elementals near walls

[@kinetic03]

used to always happen to me on playstation doom. Kinda spooky with playstation doom's atmospheric and haunting music

[@expendableround6186]

@@kinetic03 Didn't it also cause PSX DOOM to shit itself if the lost soul wandered around outside the level long enough?

[@ayjanu]

@@expendableround6186 Yep, it did. kzbin.info/www/bejne/Z3y6aoagiqeKhc0

[@mr.pavone9719]

It's odd that they don't just re-enter the map given that the textured side is facing the "inside". I'm guessing the one-sided tag is keeping them out.

[@realprion]

10:38 I enjoyed this bug quite a bit because I could use it to give the impression of a jammed door. In a megawad I made the player blows up a facility, so rather than just putting a plain old texture there I made it feel like the door was actually stuck and unable to open.

[@clonefighter1996]

-So Boom breaks that. Sorry to hear it...-

[@LabyrinthDoomer]

What was the name of your megawad, I'd be interested in playing it

[@realprion]

@@LabyrinthDoomer I had named it "The Pointless and Harrowing Journey of Marvin". It was a comedic piece that filled with inside jokes for my friends. (A slaughter map named "Element of Pain" being a great one). My laptop eventually shit itself and died and the problem is that my only backup was a hard drive that's been lost for a couple years now. Though I could ask to see if the lass I still have contact with has it. Not sure though, even if she doesn't I plan on working on my next project anyhow. Already have plans for another BTSX style chapter going through levels 1-8 but I'm not sure where I'll go from there. Probably going to some Wolfenstein type nonsense and finally make the Meat Cathedral a thing.

[@SuperShadow]

I have played a few maps that use jammed door but I cannot remember the name.

[@T3sl4]

@@SuperShadow The same effect is made by putting a low ceiling sector behind the door. In fact, make it a crusher and you can confuse and frustrate the player with erratically openable doors!

[@PeterLawrenceYT]

I so wish compatibility mode was defined in the pwad's filename as a true standard for limit removing map packs to make it glaringly obvious which one is recommended. So like the filename to always be "NAME_doom2.wad", "NAME_boom.wad", "NAME_mbf.wad" etc. Also I wish the game set the right compat mode for me, taking it from the filename as I explained above. Conflictions shouldn't apply as I don't think anyone every loads two map packs at once, especially ones using different compat modes. My main point being, why this gotta be so complicated!!!

[@Calinou]

I wish source ports could also detect which IWAD to use automatically, so I don't have to try out both doom.wad and doom2.wad when I don't remember :( I understand this is difficult to do without any metadata within the PWAD though. Probably not impossible, but it will require a lot of thinking to not break anything (even more so if you want non-Doom game PWADs to be recognized automatically).

[@TheGuyWhoIsSitting]

I can’t say I remember everything about wads, but maybe there could be an extra line or two in one of the files that contains text.

[@chrism1518]

@@Calinou Usually it’s safe to assume a WAD is for Doom 2. But I do agree it would be a nice feature to have.

[@KopperNeoman]

Even if they do conflict, can't you automatically switch compats based on what PWAD the current map is in? Excellent for mixed compat multiplayer on maintenance-free dedicated servers.

[@Shepardus]

dsda-doom has support for a "COMPLVL" lump in the wad to identify the complevel to use, but I haven't seen wads using it yet.

[@NerfPlayeR135]

I was _not_ expecting to hear "HNNNNNNNNNGGGGGGGGGGHHHHHHH" come out of decino's mouth at 17:04, but now that it has, I can't stop laughing about it.

[@CaveyMoth]

Agonizing Rectal Pain, as well

[@egorence2149]

beaks make me coom, even.

[@dunndunn3850]

The broken stairs in MAP30 puzzled me for a long time. Glad to learn about all this! It'll greatly help for future maps, and paying more attention to exploits.

[@sakucelty]

5:38 “Door Stuck!” said the first imp.

[@rolandkatsuragi]

Finally a worthy competitor to the Street Fighter II sub-series for all the inane and version specific differences between updates.

[@Moleoflands]

"It will only attack you against protects of less than 1000 damage"

[@sanketower]

Decino was sick of playing broken viewers' submissions, so he decided to do a comprehensive compatibility levels video. Moral of the story, don't just test it on GZDoom and call it a day. Nice video, I may switch to PrBoom+ some day, depending of if my Scythe 2 playthrough ends up being a power point on GZDoom.

[@expendableround6186]

Last time I played Scythe 2, I had a gore mod, and it ran just fine.

[@ravagerslb]

You need to use prboom if you want to tackle sunlust with pistol start. GZDoom will make the last level unbeatable in UV, because the beginning uses a trick that won't work and will make things wayyyy too hard

[@sanketower]

@@ravagerslb What trick? I've already beaten God Machine on GZDoom

[@DinnerForkTongue]

@@ravagerslb What trick? Be more specific please.

[@vatsalmamgain5069]

@@DinnerForkTongue I think he is talking about the thing that revived the dead enemies. That Archie-DeHacked thing. Edit: Or that candle telefragging Cyberdemon on that Secret. I can be wrong though ¯\_(ツ)_/¯

[@TheMrrandomxbox]

This will never be relevant to me as a casual Doom player, but I love watching your videos on oddities of Doom’s code and how small changes can have massive effects. Good stuff!

[@Over9000BPM]

This explains all of the deeply weird things I encountered trying to make a door that one time I attempted to make a map.

[@autumn_of_thought]

WOW Thanks Mr. decino. Tweaking comp levels has always been confusing to me. This is a much anticipated video.

[@koolandblue]

Everytime one of these analysis videos comes out, I’m always amazed at how intricately programmed Doom was and how dedicated the commnuity is to improving the game and keeping it alive.

[@privatedino3239]

Yellow videos the best

[@T-West]

So great to see this explained! I've never been a fan of demons falling off of ledges in complevel 9. But then again everything that's different from the version 1.666 I played from floppy disks in the 90's still feels off to me.

[@EMDakka]

Where's the rest of the pacifist campaigns? There are Empires waging war for ages wiating on your teachings!

[@sdwvit]

yo t-west watches decino, why am i not surprized

[@Cucuska2]

Is this a crossover episode or what?

[@Dinjoralo.]

I do appreciate mentioning using GZDoom like a normal human being. Genuinely.

[@inverse_of_zero]

18 minutes of decino DooM analysis = 18 minutes of bliss 😍

[@n00f]

9:52 was hoping the floor motion behavior would be touched upon. A recent viewer map had me confuzzled. Thanks, magic man

[@Maldito011316]

The only complevel setting I used to change were Monsters are infinitely tall, and Explosions have vertical push, both mostly for Cacodemons

[@chrismingay6005]

Not once had I ever considered that the "blazing doors" double sound effect was a bug!

[@rafaelemerencio1000]

Oh boy, I recently started making levels, and I have so much to learn. This video will help me a lot, and I will probably rewatch it several times in the future lol. Thanks decino, you're amazing :D

[@travalisarcane9112]

5:28 "Please!! I beg you! We're dead! You're a genuine dick-sucker!" Doors stuck is a classic that will have a place in my brain till I die.

[@clownpiece5992]

You should make a video about all the various Doom engine bugs and limitations, such as tooti-frooti and visplane overflow.

[@iguana9173]

Yes he should definitely.

[@DinnerForkTongue]

Tooti-frooti, VPO, VSO, blockmap (by referencing Coincident), infinite height (maybe mentioning Borogk), hall of mirrors... bugs exist aplenty after we've pushed the engine so far beyond what it was made for!

[@cakeman7555]

@BrutalGoober Zedek

[@jacderida]

Great video! Another little interesting fact btw: complevel 11 forces the use of -shorttics when recording demos.

[@decino]

Isn't shorttics the default for all demos?

[@jacderida]

@@decino Yeah, but you can override it with -longtics, but doing that has no effect if you're using complevel 11.

[@decino]

Understood!

[@Shepardus]

Same with complevel 9. -longtics is a thing thanks to a version of the Doom II executable hacked to record with longtics, which never existed for Boom and MBF. Worth noting that MFB21 _does_ support -longtics, thankfully.

[@juanchol21]

@@decino i think is forced in boom Mode but not in MBF 🤔

[@RiiViiMedia2424]

6:54 Those souls are forever lost.

[@ezgoodnight]

My RetroRGB article on Source Ports was released today, and I cited this video in it. I'd post the link but KZbin would probably assume I'm doing a spam. Love your channel, you're the reason I'm like this now, decino.

[@decino]

Just checked it out, very nicely written! Thanks for the mention.

[@SentyPurr]

Doom will always have so much quirks and tiny jank that you still discover things to this day. Also, nice choice of music. This one's from Akeldama, I believe.

[@decino]

Yep, brilliant MIDIs: ad-79.bandcamp.com/album/akeldama

[@UnkleKlumsy1353]

The fact that there's still interesting stuff about classic Doom for you to make videos about speaks to just what a great game Doom/2 is

[@ardag1439]

Thanks, decino! I was actually emotionally hurt a few times due to this whole -complevel business.

[@iguana9173]

Yup and me too.

[@Jobby_James]

It is nice that you are analysing source ports like PrBoom+ is great detail, I think this will help those get a better understanding of the significance of -complevel parameters and the differences between source ports and versions. I am curious to know what font you use for these videos, as I like it due to its legibility and typeface. I am referring to the text that is usually white with a black border and isn't text in DOOM.

[@decino]

Font is Consolas Bold.

[@doomerrasa8475]

@@decino yellow background video on doom fonts confirmed?

[@conzmoleman]

i’ve always been confused/surprised as to why the boom ledge fall off physics were generally used as standard by most erstwhile purists, since it seems like a pretty significant difference from the original id engine behavior.

[@Leahi84]

Thank you so much for explaining this. I had been really confused as to what the (-complevel 9) in your videos had meant. This was great to learn about.

[@not_creative_with_username3834]

This is awesome, well written and very clear and undestandable even for a casual player like myself.. thanks!

[@WSADKO]

This video needs to be seen by any aspiring doom player

[@zatozatoichi7920]

Most of the aspiring ones already know about this tho.

[@TVdinnermasterchef]

Another great analysis vid mate. When I eventually get a PC, I will consult these vids on mapping tips whilst making my own maps. I'll call my WAD Sunlost, since I'll be aiming for Sunlust but, sadly, ending up miles away from my intended destination.

[@Rozay403]

I was so perplexed by the stairs thing when I was doing my TNT pistol start run! This explained it though, holy heck. Blessed af that I got my decino fix. Love always!

[@AjStormheart]

I had no idea that doom had this many levels to how it ran, also I agree with the double door close sound, having just play once did not sit right with me and felt off considering I grew up with the game, its just a little charm.

[@peterhawes9680]

Thanks for more great eDoomcation, Decino. I recently had problems recording a demo for Map 14 of Valiant because I had tinkered with the compatibility settings a long time ago but it didn't cause problems until doing an MBF map.

[@cherubswrath8820]

So basically, PRBoom+ is the linux of doom engines

[@TheHardGameQuestion]

so what is windows?

[@omegasaturn3598]

​@@TheHardGameQuestionGZDoom

[@DoomKid]

Someone has probably told you this by now, but if you have 2 shells left in the SSG, vanilla doom and doom 2 will not play the reload animation (which makes sense) but -complevel 9 will. Great vid as usual man.

[@decino]

I briefly mentioned it in the weapons overview video.

[@greenguykanoe2912]

Love me some ducino's educational videos. The editing is top notch

[@LeeAndergen]

Not only informational, also *really* useful! Thank you for making this video

[@markh.876]

"PrBoom+'s Compatibility Levels Explained"? That's the worst misspelling of "Going Down Level 09" I've ever seen in my life! :)

[@emmecuh]

Or maybe "Stardate 20X7 Map 3"

[@Erik-bt3om]

I think GD map09 is going to be the end of Decino's blind run victory streak.

[@lhfirex]

Maybe it's "going down compatibility level 9" instead!

[@CounterGoose53]

I just swapped over from the 2024 steam port to PrBoom+ and this video is a life saver. Thank you Pumpkin Man

[@thestabbybrit4798]

The most intimidating thing about classic Doom is figuring out how to launch it.

[@mrscruffles801]

Through Doom Eternal

[@zatozatoichi7920]

In the age of Google, it really shouldn't be.

[@evenfallabeksylt9271]

Possibly the first video I've seen where the author thanks some AGONIZING RECTAL PAIN. Also, good for another analysis video, it'll help drive the subscribers count up and ultimately draw near the next Sunder adventure!

[@MateDrinker33]

My memory isn't good, but I think he MIGHT have appeared in "Why Can Mancubus Fireballs Go Through Walls?".

[@evenfallabeksylt9271]

I really don't know. Everything is possible at this point.

[@СергейМисюк-ж1к]

At the beginning of all things... Decino mutated. This gave him a superpower of explaination. Which is cool. Because I always like to know more about doom, and compatibility is one of that things that concerns me the most. P.S. All these fragments of gameplay footages gives me what we russians call "Vietnamese flashbacks". Even though I didn't played most of these wads yet.

[@GameplayandTalk]

Great video, I've always found the complevels confusing. This cleared up a lot of questions I had.

[@Spectere]

I literally hit the thumbs up button the instant I saw the title. Thanks for tackling this!

[@theineffableword1072]

These videos always bring me a cozy comfortable feeling. Thanks Decino :)

[@ihatetrollingGaming]

this video convinced me to give prboom a try, and while I've kinda been spoiled by gzdoom's general smoothness, prboom is honestly a pretty good engine, speaking as a non-purist player doesn't change the fact that the chainsaw is a fucking hideous stuttering eyesore in prboom

[@csikocska]

I didn't know about compatibility levels inside source ports. It's good to know that the known issues are fixed in PrBoom + and GzDoom in default settings. Thanks for this informative video content. :)

[@plazmasyt]

I counted the Souls in the thumbnail. Only 19, there's still room for three more before the limit is broken, so maybe that Meatball shouldn't be looking so smug. How can he be sure the limit is removed? c:

[@fus132]

11:04 "Collapsing E1M1 isn't real, it can't hurt you" Collapsing E1M1:

[@QuotePilgrim]

"you can just use GZDoom like a normal human being" cracked me up 😆 I don't like using GZDoom for anything that doesn't require it, but I also am not super concerned about 100% accuracy. If a wad runs in PrBoom+ then I'll just use PrBoom+ without specifying a complevel, if it requires GZDoom, I'll use GZDoom. I can only see myself using a specific complevel if the map I'm playing really only works with that complevel and breaks otherwise.

[@Dollar_Store_Cacodemon]

Been reading and watching a lot of tutorials/guides on PB+ lately as have only been using it for about 4 months. This was useful and interesting too, thanks dc 👍

[@Carnage7162]

These settings were always confusing for me and it was one of the reasons I uninstalled all versions of Doom and stopped trying to speedrun it. My career ended before it begun :(

[@technoman9000]

Awesome thanks for going through all those settings, my eyes glazed over when I opened the PrBoom+ options...

[@dromendus]

hey decino am I allowed to piss in the comments or do I have to go somewhere else

[@decino]

Whatever helps the algorithm.

[@patmurphy7603]

Damn I actually really needed this video lol. Recently got a new laptop and I've been wanting to play some wads but really have no idea what to use for various ones. I know some stuff but definitely not NEARLY as much as I'd like to. So any future videos on this stuff like u mentioned will be most welcome lol

[@adammclaughlin845]

Using Gzdoom is like playing games on console: as simple and streamlined as possible. Using PrBoom is like gaming on PC: extra layers of complication that people insist are needed, when they aren't.

[@mrscruffles801]

Yeah, simple and streamlined until you look at the options menu.

[@Cataflexia]

your videos makes me teleport to my childhood when i've my 486 dx2. and of course, great information! it clarify me many question that i have. thanks a lot!

[@biggiestos2361]

DOOR STUCK

[@lukepardini2307]

Really enjoy these in depth videos where you explain the inner working of Doom and the source ports. Keep them coming 👍🏻

[@DasPanoptikum]

This video made me realize, that I will just stay with GZDoom. Looks like I'm just a normal human being

[@expendableround6186]

I know sone will get irritated with me due to my remarks, but akin to a pair of a _wired_ headphones, one can plug in GZDoom to nearly anything and it will work almost all the time. Do yourself a favor and get an extensive set of source ports, though. You're only twisting your own legs if you only use one.

[@Orochi97Jr]

6:53 7:00 The Lost Souls are living to the their name.

[@SomeDudeOfficial]

5:26 *get out of my way man! dOOr stUck! dOOR STUCk!*

[@JiggyA]

Thanks for this. Your Doom content is the best and I always get pumped up and more motivated to play after watching your videos.

[@THEpaulyBOY44]

I have always had the bell on for your channel bro and I don’t know why but I haven’t had a notification for months from you I just came across this vid and realised not just I have missed so many vids I have to catch up on but damn my guy you have gained some subs I’m glad you so deserve it this channel is so underrated for old skool DooM 👍🏻👍🏻👍🏻👍🏻🇬🇧🇬🇧🇬🇧🇬🇧

[@humanbeing_]

NICE! Great idea for this video to explain all of these things. As always, GREAT VIDEO! 👍

[@osmo_9577]

Awesome in-depth -guide again! This will help me muchos with my amateur mapping project. And that Spoopy Boi in ~8:30 is doing some... Very spoopy stuff😂

[@FioFiorello]

I work really long hours and have to take the train home for about an hour and a half at 3am. I get home a few hours before i have to be at work again. It sucks every time, but when Decino uploads an analysis? Well, on those nights, I feel alright!

[@Filip.777]

13:44 that blue key is very aesthetically pleasing, love it

[@decino]

Obscure little feature where keys reset the yellow bonus screen blend.

[@Filip.777]

@@decino very interesting, I tought it was just good timing haha glad that I noticed it though

[@Chozo_Ghost]

ZDL (ZDoom Launcher) is also a really handy way of loading in WADs and Complevel parameters! Also yay, more Tooshie :D Also LOL at the "Just use GZDoom like a normal human being" joke. That's the source port that I've mained for years now, and have just recently started doing more tinkering with PrBoom+ and DSDA-Doom. It's honestly hard to pull away from one that I've used for so long so I usually just say screw it and stick with what I know.

[@expendableround6186]

I honestly gave up trying to figure out PRBoom+ because I'm much too dim and impatient. I'm not trying to be an ultra-competitive player, I'm just trying to play a game. Oh, and ZDL is a lifesaver.

[@JunayedMahin]

ahh peace of mind about a week ago i commented about making a video like this and its here already . thanks mr .Decino

[@wilburthemango]

awesome video as always decino!

[@erickbirkin3622]

Maybe the most useful video so far, at least for me. I always have a mess in my compatibilities settings. Thanks bro.

[@JouMxyzptlk]

I was one of the boom beta testers, right after the source was released. Boom back then was the only engine which not "increased" the limitations (visplane oveflow, HOM when complexity gets to high etc), it REMOVED those limitations. Caused quite some funny bugs, and making them reproducible was the challenge.

[@cubesolver2564]

0:22 I love the homage to ITG/Simply Love with those arrow graphics.

[@Roy-hn4ek]

decino being the greatest DooM buddy ever. Thank you for this video, made a lot of things clearer for me. :)

[@thewaver8]

Fantastic as always! Waiting for a port comparison video one of these months... :D

[@Gleanerizer]

I figured this video was coming sooner or later. A great overview of the topic, thanks for this! 👍

[@the_fatshark]

Thanks and great analysis video once again. So much more clear now all those comp level terms.

[@rayft1422]

Awesome Video Thanks.. Sorted out out a slight non-infighting problem by using the correct Comp Level.. Who would have thought 😅

[@alexbaxthedarkside]

Thanks for this vid Decino it is Super useful, only bug I can recall which didn't occur to me as a bug was being telefragged by a monster spawn even with iddqd invulnerability enabled on icon of sin on vanilla Doom 2, so yeah this is super useful, was not aware of alot of these, very interesting and informative!!! :)

[@batsuuri.gantulga]

I never knew there were this many compatibility options for wad files. I have learned something today. Thanks, decino!

[@maxonreese]

5:26 "OUTTA MY WAY SON!"

[@RetroGamingWithEdgarRivera]

That's quite fascinating in fact I was testing some Boom Wads maps on crispy Doom only find it out that sure enough it requiers PrBoom to play correctly as I start to play more Boom wads the more I understand the compatibility on each Wads.

[@bauul.]

FYI Crispy can never properly play Boom maps: it's a purely limit-removing source port, so aside from removing some basic limits has no support for anything other than the features available in the vanilla game.

[@VGamingJunkieVT]

7:55 The funny thing is the invulnerability powerup isn't affected by the death floors, possibly an oversight. You can just type idbeholdv and you're safe in all versions.

[@ruinsleepless9098]

Bahaha, good to know I'm not the only one who makes that sound when they screw up a VO recording, can't count the number of times I've done that now. Handy info though, thanks for compiling it and making it easily understood

[@carl.wunsche]

I've been waiting for this one! Thank you decino

[@TimeofDying00]

Oh wow, I never knew that double door sound was a bug, I just always assumed THAT was the sound. See, this is why I come to these videos, I can still learn something about a game I've been playing for almost 30 years.

[@viti95]

Thanks for this video, I've been able to understand much better complevels and add correct support to FastDoom thanks to it!!

[@xX_Lol6_Xx]

Little fun fact: In chocolate Doom and crispy doom you can also use "complevels" by using the -gameversion command to emulate the desired exe, normally it's not used since they emulate the behaviour of the game based on the Iwad loaded. Obviously you can't use boom or mbf wads, but it's still cool nonetheless

[@VaterOrlaag]

2:35 I actually tried running Eviternity in plain old MBF under DOS (well, Dosbox) for giggles. It crashed on loading map 2.

[@INFERNOPL999]

Thank you, this is great! Exactly what I needed, you're the best!