So hypothetically you could kill all the monsters in a level, and then get killed before the exit by a clipping projectile

“You hear a Mancubus talking smack about your mum” already love this

" We like fireballs, let's give them IDCLIP. " - ID Software, probably.

"Walls? From where we are shooting, we don't hit walls" (probably, one of the Dead Simple mancubi)

Good things in life: Chocolate Friendships Decino uploading a yellow-background video

Fun fact: this is actually how shaped charge projectiles penetrate tanks.

the overflow glitch is really fun - there's a map in NoYe called, well, Overflow, where you have to fire rockets down a corridor for two minutes and then hide in a small alcove while a couple hundred enemies spawn in front of you, eating your old rockets (and your new ones, you have to team up with your past self!)

That guy's Patreon was worth it just to make you read "Agonizing Rectal Pain." Also very informative video!

"You know, whenever I want to analyse a feature in Doom I always think: huh, that's not too complicated. Finally a short analysis video that won't take me a month to make - but then I discover stuff like..."

As an extra fun fact, this effect is also behind the BLJ in Mario 64. In fact, all video game movement is effectively teleportation if you don't code in some sort of interpolation. If I'm not mistaken, that's what the FASTPROJECTILE flag does in GZDoom.

If you're having trouble being hit by projectiles clipping through walls, then the solution is obvious: simply jump when the demon fires at you. That way, even if the projectiles do clip through the wall, they'll simply fly over your head harmlessly when they reach you!

Pro Tip: In order to prevent projectiles noclipping through walls, simply prevent the monsters from shooting at walls.

don't forget, the fact that mancubi always shoot multiple times even after their target is out of sight also makes their projectiles do this more often

Doomguy’s eye-bulging 😐 face will always be unsettling.

so interesting to finally have the nuts and bolts of this explained. In Map29 of Scythe the room at the top of the lift with shotgunners has mancubi outside, and that wall there is terrible at keeping their fireballs out.

That's horrifying... Imagine a stray projectile hitting you when you're low on health, and said projectile hits you either on your way to the exit switch or when you're about to press it. Also, someone should have a Petron named "Mother Demon's Womb." or another twisted Doom-related pun for Decino to say during the Credits.

Saw this happened in Doom 2 map 8 when Looper was speedrunning. Baron from the room to the right of the exit room shot through the wall into the pre-exit room, hit Looper, and dropped him into the death pit.

Good to know, never knew a wall would scam me in a game.

Awesome video as always. Just ironic that you increased the "shout-out Patreon limit", and now it seems we're just as many (if not more) than when you inforced the new limit. Crazy. Keep it up!

3:05 “Did I pull these numbers out of my a*s? Ehh, kind of.” - Decino 2021

"Agonizing Rectal Pain" Never thought those words would come out of your mouth in that order XD

4:07 he had a... BONE to pick with that Revenant aaahahahahaha gottem 🦴

Man I've been hearing random fireball explosions in my games forever, finally know what that's about. I've got a good video idea! When I'm in normal Doom 2, sometimes I'll noclip out and run in a straight line for as long as I can. Eventually, I'll start hearing aggressive monsters, even if all the monsters in the map are dead or most of em, but I'll hear a bunch of monsters, then eventually I'll end up back at the map borders because of position overflow, and the noises will stop.

Analysis videos like this really make you appreciate just how intricate and complex Doom’s programming is and how ahead of its’ time it was when it was released.

Doom: A game so merciless at times, that not even the walls will save you.

All of these years and I didn't know this was a bug in the game. Makes me wonder how many times I've died to this and raged because I couldn't see any monsters shooting projectiles at me.

It's amazing how many small details there are, I dread the day you genuinely run out of things to explain Do you see yourself doing these kinds of videos for other games in the future?

that footage from the hell revealed playthrough made me feel kinda nostalgic

Any chance the no clipped projectiles can harm the icon of sin? Also, going to guess gzdoom fixes this unless you play with strict compatibility set?

I love how Doom is nearly 30 years old and yet not only does this channel frequently find something from it to talk about but they always manage to make it extremely interesting.

4:50 the disappointment in his voice as he has to read that name

Doom is so fascinating even all these years later, what a game

Good stuff. I didn't know fast monsters also triggered this bug. FYI, you mixed up cardinal and ordinal. Cardinal is NESW; ordinal is diagonals.

I think the one way I can interpret the mancubus fireball passing through stuff lore wise is probably because the fireballs (even from other enemies) are so hot that they phase through walls thin enough but dissipate upon contact with flesh or thicker walls. Basically like throwing globs of hot gasoline at foes.

Another "yellow video" topic suggestion: I was always really amazed about Doom's lighting system, especially in terms of rendering its world in the original 8 bit video mode. The rendered colors of a texture or a sprite depends on the brightness of the sector and the distance from the player, except when using light amplification, when everything is rendered with their original colors (I guess). I would really love to learn about how this is achieved. What palette is used and how are the rendered colors mapped to achieve that shading? Is there a restriction for usable colors for the textures and sprites? Is the palette temporarily altered when using a rad suit, berserk or invincibility and when receiving damage? I suspect so but then how is it achieved in invincibility mode that the sky and the HUD remains unchanged? Do they use separate palette colors? It would mean that all textures are allowed to use just a strict subset of palette entries to work properly. Some specific textures (eg. lamp and candles) remain always bright even in the dark or from far away. Are they just left out from shading or do they use specific palette entries that are simply not transformed? Or isn't there any restriction for the textures and is everything just quantized to a generic static 8 bit palette (eg. RGB332)? Of course, all of these are not relevant when using modern Doom engines with 32 bit rendering. But achieving all this using just 256 colors... it must have been quite challenging.

That explains the random explosion sounds that scared me during all of those years playing Doom. Happens around maybe once or twice a year to me but it always gets me good. Luckily the Mancubus fireball thing hasn't happened to me but more than way too often I get blasted in the face by the Revenant missile clipping through the wall. I guess Im just unlucky when it comes to the spook-bois.

That answers that mystery from Hell Revealed! I just recently watched that video and remember how confused you were about it at the time. It’s very interesting to now learn how that happened and I can appreciate it even more for how truly rare that actually was! Thanks for this video!

For anyone wondering if this issue occurs in other games or looking for something to relate this to, this is essentially the same reason why Mario can sometimes clip through things in Super Mario 64 given good enough speed and angles. I don't recall the specifics unfortunately (though if you want that you can watch some UncommentedPannen), but the gist is that if the wall or floor is thin enough and Mario fast enough that Mario can be in front of it for one frame or so and then behind it the next, Mario will go through it even though its solid.

So that's what caused Hexa's first death in his Doom 2 revisited let's play.

The collision size of mancubi fireball is always so surprising even when you know it and how it always tends to catch you off guard and now this on top

04:15 Freakin' insane. That explains why so many times while playing in UV-Fast I'd ocassionally hear projectiles exploding

Mancubus is too strong when they're telling your mama jokes xD 0:42 decino is doing speedrun lol It's interesting that you can still get surprised by 20+ years old game. It'll never stop surprising us. Doom is *Eternal* xD

It's incredible how, 25 years later, we are still talking about this engine. It's a lesson in game design!

4:20 this is the first time I noticed the *Get to it* map has a scared face in the top.

This was one of the most annoying things I’ve ever put up with in doom.

Yay my first time getting to be a patreon! Awesome video as always 👌

Awesome. I did not know that the projectiles could wrap around the map and come back in from the void. I am more than sure now that I have heard the sounds of various fireballs hitting the boundaries of the map seconds after combat over the last 2 decades of playing.

Another excellent analysis video. I really like how you visualize everything as well.

Well the game doesn't say that nightmare isn't even remotely fair for nothing

Big Mac Davis never uses a wall against Mancubus, because it uses projectiles and why block when you can dodge, he's such a strafing pro like any Doom god.

That's first time I saw someone mix the funny game with science and programming Thanks very much bro for your nice work

the amount of info this guy dives into to keep up with content is insane. major props

That Doom lesson on a good Sunday morning, thanks decino, amazing work

4:26: When viewed overhead, this map looks exactly like a monkey covering its ears! :D

4:00 And on that day, satan said: *_"Fuck this revenant in particular"_*

Dude! DUDE! I *just* started your Hell Revealed playlist today, and when 3:45 happened, I thought to myself, "Surprised there's no yellowback video on clipping fireballs..."

Always interesting to learn about how they used to optimize things in the past, even when the methods may have had their own shortcomings. Wonder if they left this in on purpose like this though in those few instances, cause as you mentioned, they seemingly changed few of these in a way that should prevent collisions to fail. Almost seems like this may be the case for one thing or another... Makes you wonder x)

I didn’t actually know walls weren’t solid all the way through! I love these videos, this game has a lot to unpack behind the scenes.

Imagine if Hell Knight's fireball clips through the wall and hits the revenant on the other side of the map. It's kinda funny to see a revenant not giving a single crap about you and trying to get something nonexistent.

It's funny how projectiles just wrap around the map like they're going around the planet

decino, you've got me playing on PRBoom+ and I have to say, I like it. I played on GZDoom mainly before, but I've been using Boom and I can see why you like it. There is just something about it. It feels very vanilla, but also smooth and responsive, as well as fixing the blood colours. You've turned me into a purist. A couple of years back when i first started watching this channel I was playing with Smooth Doom, IDKFA.WAD and Bolognese mod. Now all i want is the spritefixes, widescreen hud and sweet midi.

It's great that you covered this bug, I remember a Hell Knight projectile clipped through a wall while I was playing DOOM 64 on the Nintendo 64, in Level 06: Alpha Quadrant. I swear I was able to re-create it, but not in the 2020 PC port, then again that was 2-3 years ago since I last played that game and I can't exactly remember. Also how long does it take to make these Analysis videos? Especially ones which are around 10-15 mins long, I've tried something similar and it took me around a month (then again it was a completely different game and it takes a while to set it up).

decino: answers the question precisely and quickly also decino: now allow me to explain how this can happen with every other projectile in the game and give more detail about their speed and size

The best part of Decino videos? Listening to him say all the naughty names during the credits... xD

Game's broken. Time to uninstall.

0:34 quickest video ever

@4:06 That wrapping fireball hit is amazing. Congrats on capturing it!

As I said before, your videos are a full Game Design course on a real project. 100/100 would enroll to such a course.

The day was meant to be this good. Thanks!!!!!

2:08 i have a strange feeling that when you said "its the same as the plasma bolt", that in terms of code it was made (mostly) the same. idk, just a hunch

This stuff is fascinating. Kudos to you for taking time to analyze all of these.

Amazing as always, great work, decino!

It'd be cool if one of the future mod compats like MBF22 would allow for tighter hit detection like in GzDoom, to solve little issues like these, and to make melee combat much more fun.

Why do people love this crappy vintage game, where not only player-wall collisions are screwed up (wall-running, elastic collisions, Zero-Master clipping out of bounds) but projectile-wall collisions too?

This was great, cheers dude! Always love the game mechanics videos.

I knew about this phenomenon but as usual your visual aides and thorough explanation made it perfectly clear. Well done as usual man.

This is a bug called tunneling and is quite common in game projectiles like this if not fixed. There are numerous solutions, but a common one is not to detect collision on the projectile, but actually on a ray that is calculated between the previous position and new position - that way it sees if anything between the two positions had any walls or the such between them.

Zap Rowsdower definitely plays Doom. He downs Molson beer, lives in the back of his truck, wears acid-washed jeans, trims his mullet, and plays Doom.

That solves my issue of seeing some projectiles passing through walls, thanks decino.

that rev missile width reveal, shit no wonder i get snagged by them even when i thought i barely slipped away

The shocked Doomguy faces are brilliant. Also this was a really nicely done short analysis video! Can't wait for future ones :D

Your meme thumbnails are the best, glad you put them on display at the end of the video

I often assume these videos are going to be boring or confusing, but I’m always wrong. Your visual aides are awesome and this shit is always interesting.

I can't tell you how many times this would happen to me when I would be playing doom. I needed this information. Thank You!

"Thanks for watching, this video was brought to you by Agonizing Rectal Pain" I think I'll pass on the sponsor k

Amazing content as always, and loved that intro lol! Learnt something new too.

Adore your tutorial videos, keep doing and have a lot of fun.

I am frequently astonished as to how much I've played Doom to the amount of seemingly obvious bugs that I have never, ever encountered

Thank you Uncle ducino for solving this age old mystery!

This is my first video I ever watched on your channel!

decino: explains the topic in under a minute decino: *-But Im not done yet*

AGONIZING RECTAL PAIN that's a beautiful name, respect

I really love your sarcasm and irony used in recent videos. This is what I'm trying to imply in my vids xd

Another great video. thanks decino.

another way to chill by watching analysis videos by decino :))

Cool fact: because doors/lifts are solid areas, and almost always thicker than the gap between tics, they are reliable armor against Mancubi, or anything else on -fast. (Most doors are 8 or 16 thick; you can make them all the way down to 1, or less than 1 I suppose if it's a triangle corner, but who would do that?)

love your analysis videos. Learned so much about doom from them

My favourite part about this bug is when I quicksave while at low health and get soft-locked by a sneaky wall-hacking chunkubus

It's funny when you show these bugs and I'm like, I've been playing doom *since* 1996 and if I *have* seen these bugs, they've been rare enough that I probably just don't remember them. But then you are like, "Here's it happening, multiple times in a row. It's common!" Truly, I art the most casual of Doomguys.

Thanks dude, love the analysis videos. Even more info with which to improve my chances. If only my reaction speed was as fast as my recollection.