Oh the memories of doing Eternal DOOM (not to be confused with DOOM Eternal) co-op run in 90s LAN parties. The amount of times the sentence 'oh, it was you? sorry' was uttered...
Important to note for GZDoom types: You may notice enemies do NOT spot you by default. However, in vanilla, enemies will still spot you through the power-up. Heretic's Shadowsphere DOES have the GZDoom style mechanic in its vanilla game though!
Honestly always liked the enemies not spotting you with partial invisibility. I began playing on Gzdoom and was disappointed when i moved to other sourceports that didn't have that
Funnily enough, one of the recent GZDoom versions (4.12, but seems to be fixed now) somehow broke angle randomization completely. So you would have enemies attacking you as if you didn't have it.
Also important to note pretty much the whole ZDoom family of ports has this, including ports like Zandronum. The change in behaviour came when ZDoom got Heretic support, because the code for that behaviour from the Shadowsphere was intentionally added to Doom's Blursphere. The early days of advanced Doom ports was a wild west of changing the game's behaviour, keeping the vanilla game as is in more advanced ports largely started with PrBoom and its descendants, with their features like complevels.
If you play around with it in GZDoom you'll notice that sometimes the enemies notice you anyway. They have a random chance of spotting you if you get too close or move too fast, so keep your distance and move slowly (slower than walking speed) and you'll remain hidden for as long as the powerup lasts. This is also taken from Heretic's Shadowsphere.
I love that Doom has this surprisingly in depth implementation for its fuzziness effect, then its RNG table is just 255 random values with no real logic or weighting to it. What a fascinating game
Shaders weren't a thing back then (because graphics cards weren't a thing). I played Doom on a 386 (under 40 MHz) for example. That CPU had to do EVERYTHING -- not just collision, player input, and enemy AI but rendering. They simply couldn't do complicated algorithms to mimic shaders outside of table lookups. It is impressive that they accomplished what they did.
There IS a weighting to the RNG table! It's a rough bell curve with a slight bias towards the high end. Decino has shown plots of it in previous videos.
Fun lore fact Spectres are pinkies with a cacodemon eye put inside of them giving them psionic abilities in doom 2016, if we apply this logic to the classics then the invisibility sphere is a cacodemon eye.
Processing... Initializing... New headcanon accepted. Error... Cursed thoughts detected. Are we just chomping down on that powerup, or do we just crush it in our hands to achieve power?
As a kid, I couldn't understand English very much, but I knew what "Invisibility" meant, so when I picked it up and the monsters still saw me, I thought the demons use thermal vision like a Predator or something. Didn't even notice how it works, because I was a stupid child and strafing was something I didn't do at all, so it should have been obvious. Yes, I struggled with the Cyberdemon, how could you tell?
Can Maulataur in Heretic be beaten on lowest difficulty skill by using arrow keys only? With Ring of Invulnerability, yes. Maybe this is why my mom liked Heretic more. You should try Heretic, it's easier than Doom I guess.
@@CsubAzUrmedve Szia Csúb! I also started with Heretic, I was like 3 years old when I played it on a Windows xp that didn't had any audio card and I played using the arrows and for slower movement I used the mouse. I love Doom and I'm also planning to make a total conversion Doom mod similar to Ashes and Hedon!
I never really cared about the partial invisibility powerup until that one map in Plutonia where you pick it up and this huge window opens and you're surrounded by monsters, a lot of them hitscanners. I thought I was done for until the chaingunners opened fire and they missed almost all of their shots. I took the initiative and started cleaning house. That was a pretty memorable fight, and it goes to show that good item placement can really elevate a map, just as much as where a mapmaker places his enemies.
The irony is, in most shooters a blursphere or similar item would be unambiguously good, because you had no chance of dodging all the bullets anyway. You're basically hoping the enemy misses you, so a higher chance of that is never bad. In classic doom (especially nowadays) that's only true for hitscan, or in rare cases where there's just a comical amount of enemies shooting you. It's an item that makes sense in every fps except the one it's in.
“The Revenant’s homing missile doesn’t care for your partial invisibility” has the same energy as “The missile knows where it is because it knows where it isn’t”
I'm pretty certain I've seen maps that force you to get a partial invisibility and have to run past a room full of Cybies lobbing rockets at you. Talk about evil.
I HATED the Invisibility power up. I was already good at dodging rockets 🚀 and fireballs 🔥 but with the Invisibility power up I start to zig and I get hit because I should have zaged. I end up running into projectiles. Would piss me off with a passion.
yeah I just avoid it most of the time cause its easier to just dodge predictble firing pattern. could be good in areas woth not enough room to move around, but thats it. For hitscans, its always good though.
It's a pixel shader before shaders were a thing! Might be a fun little exercise to implement it in GLSL. Maybe I'll give it a shot when I get back to my computer.
Imagine how much data should operate PC while running this game. Never before thought about it, till watched this video. And it's huge work was made on dawn or game industry by people, without any ai helps and tricks.
Magenta does have a significance in the works of H.P. Lovecraft that inspired Id Software (at least John Romero and Sandy Petersen), but I'm not sure if the people behind Eternal Doom were familiar with it, at least none of their map names reference any of Lovecraft's works.
The Revenant missile knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the Revenant missile from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is.
An interesting exercise would be to combine hitscanner attack accuracy data with their rate of fire and get DPS numbers (given the player doesn’t break line of sight the whole time). Could be valuable for mappers who wish to provide tight and precise challenge.
It's hilarious how the level Dead Simple has several partial invisibility spheres but pits you against enemies whom the effects wont benefit you from. It's like even the guys at id didn't even know how they worked
the idea of a power up that scales in power based on how *gaudy the background is* is deeply, deeply hilarious to me. like imagine if a new weapon were to get released in smth like Fortnite or Splatoon or Third Example Of Contemporary Shooter Game With Any Emphasis On PVP, where it has an ability directly correlated with how much *plaid* is in your surroundings. gotta love a weird engine quirk like that. ;P
Curiously enough, this still is an issue in modern games. As an example, some fighting games have banned some characters' alternative costumes because they would remove or hide certain visual cues.
Tournament bans also extend to stages due to visual noise or other issues - IIRC there's a Street Fighter 5 stage (a flying plane) that's banned in organized play because the swaying background can give you motion sickness.
Yeah, because PSX Doom didn't have a specific entity for invisible Pinkies, so technically there's no specters in PSX Doom, just Pinkies with the translucent flag on applied to the map thing directly. There was also a flag to make any entity subtractive and double their HP, that's how they made the Nightmare Specter, but you can apply that flag to any enemy. There were Nightmare Imps during development but were discarded, there's a magazine scan with a screenshot of one in E2M6, but you can easily make any Imp a Nightmare Imp by enabling the flag on one of them. Barons look pretty neat with that flag too!
Just the other day I saw in a Corridor Crew video that they use yellow text in their thumbnails because it's an eye catching color. But Decino is miles ahead of them
That's definitely the most annoying thing when you pick up partial invisibility when you've been playing Classic DOOM for so long. You're so used to dodging projectiles and your muscle memory kicks in and you dodge right into their projectile. Also thanks for showing us the mechanics behind partial invisibility.
On the Super Nintendo version of Doom, the partial invisibility power actually makes you invisible to monsters. You can walk right in front of them and as long as you’re not inches away they won’t see you. On the SNES the Partial Invisibility sphere is one of the best power-ups in the game. The SNES version had to cut some serious corners but this is one instance they actually improved on the original game.
Yeah, the SNES version was the first one I owned, then playing other formats made me wonder what was broken about the invisibility. The SNES version did have a couple of interesting aspects with the weapons - I believe the shotgun was just a single shot with a heavy damage multiplier over bullets, making it more like a long rifle, and the BFG worked differently, with a big splash like a souped up rocket launcher. Plus there was a fun bug where the backpack gave you ammo for weapons you didn't have yet and you could trick the game into giving you a single shot with "ghost" weapons by switching and pausing weapons.
The partial invisibility probably works that way on the SNES to compensate for monsters' lack of sprites that aren't front-facing. Which means it's outright impossible to ambush them.
@@NerfPlayeR135 yeah, for sure - it was a very cut down version, but given that it was on a system a lot less powerful than the other ports, it was a bit of an amazing feat to have so much available in the first place
@@BPCRevere SNES Doom was what happened when a miracle-worker has a passion project. That cartridge was so overstuffed with hard work and mad talent that it's a wonder it didn't explode.
I remember reading a post in the Doomworld forums about someone "fixing" the fuzz effect so it didn't overdark already drawn pixels and it looked extremely cool.
It was quite a strange experience when I made my friend play Doom for the first time, since when he picked up a partial invisibility he said "This is quite useful for dodging!" I was so taken back I almost jumped out of my proverbial socks.
The thing is that it messes with muscle memory of seasoned players who already know the patterns and dodge instinctively, often preemptively. A new player, on the other hand, tries to avoid incoming fireballs on the fly, reacting as they appear to the new changed angle and it is easier for them since the projectile doesn't fly directly at player.
Genuinely didn’t know about the top:bottom row pixel quirk, and I try to collect obscure facts about the renderer like that. It makes me wonder if the fuzz effect could make use of the transparency maps in Boom, or define what row of the palette to use. It’d be pretty cool to have something like a red spectre that’s slightly easier to see but still has that classic slightly janky fuzz going on.
@@simonsoupshark8009 everyone knows that in 2024. But in 2001, a 8 year old me who didn't even know how to read properly had the right to be frustrated
The more you get into decino's yellow thumbnail videos the more you realize what an absolute technical marvel this game was for something in the early 1990s.
Finally, after all these years, I now understand what this really does. Back in the day it always felt like the powerup is broken because enemies still spot and attack you like normal. Never really noticed the weird angle changes and different projectile flight patterns.
Amazing what the DooM founding fathers did back in the day with the technology they had all cooped up in a house. No Scrum or Agile methods needed. Just a handful of talented computer nerds who believed in their project. Thanks so much for breaking it down for us, decino. These videos make me appreciate DooM and whole lurch forward that videogames did in the 90s even more.
I really like the chill music as it sets a very good learning environment. It's interesting how much RNG is in this game and how it adds up to the complexity we're still looking at today. It's simple but very complicated once when multiple actors are involved. I guess you could say it's like Chess... but the pieces move around in real time and have to check a 10 page table of values for everything... and one of them has a super shotgun.
I always found it funny once you're good at doom the shadowsphere actually hurts you because you constantly get shots leading your strafe. I really like how Brutal Doom upgraded it, so you aren't noticed from a distance until you attack.
Wowowow, it never ceases to amaze me how many details I didn't know, despite thousands of hours playing and hundreds of hours in the code. Love this series. ❤ I especially liked your explanation of the color map, and the funky exploits you can use for evil level design, as if randomized offsets wasn't interesting enough. Very well done.
The blursphere is one of those nuanced powerups that mappers don't seem to know how to use to its fullest extent. There are more uses than anti-hitscan protection or extra challenge in a projectile-based arena. For example, a combat puzzle where your movement is restricted so dodging projectiles is harder could benefit much from a blursphere secret before it - not as broken as an invuln but still a big help, similar to the radsuit secret in Stardate 20x6's Vehelits, that makes the last ambush a lot more manageable. Oh, there's also yet another name for this powerup: Quantum Stone. Credit to Zeppelin Armada for this one.
One of my favourite uses is translucency in the BUILD engine. The games include a 64KB lookup table of all possible pairings of colours in the palette and which entry is the closest match for a 2:1 mix. The nice thing about using a 2:1 mix is that it lets you do two levels of translucency with the one table (four if you count invisible and fully opaque). Look it up one way and get the more-opaque version, and swap the colours being looked up for the less-opaque one. It's not an insignificant amount of memory when the game has to run in 8MB, but it makes enough of a difference visually to be worthwhile. You could extend the concept with additional tables for more levels of translucency, too. For 8 total levels (including invisible and completely opaque), you'd need tables for 6:1, 5:2, and 4:3. If you wanted to go to 16, then you'd need 14:1, 13:2, 12:3, 11:4, 10:5, 9:6, and 8:7. Beyond that, you'd probably be writing for a system fast enough that you'd no longer be bothering with palettes and working directly in RGB, or using hardware acceleration.
"Okay invisibility, great for first time players, a fucking curse for veterans, because what it does is makes monsters more inaccurate and they have a harder time hitting you, so muscle memory kicks in and you dodge right into their projectiles" Civvie 11's video on The Ultimate Doom
@@decino Well, at least we got one member of the family still there, the possiblity for a family reunion is still possible! Also I do got a question. I know you're very unlikely to do anything regarding DOOM 3 because, well it's doom 3 (though I did get it recently, still looking forward to playing it!) But I am curious if you're ever going to tackle the modern doom games a bit more in-depth. More specifically, if you're ever going to tackle DOOM 4. Since more leaks and stuff were found regarding it and it's made me realize just how much of DOOM 4 survived into 2016. Was just curious if that's something you plan on talking about on the channel down the road. Also loving these videos still! Seeing these quirky things like the effects the magenta room has at the end of the video, and the effect at 12:11 has been inspiring my map designs in other games! Sorry for the long comment, just a big nerd is all, lol.
@@decino Fair enough! I am admittedly more interested the horror side of doom and honestly, the art direction of DOOM 4 and 2016. Gameplay wise, I'll be equally as blunt, they're awful. But man, I do love the horror ideas they were trying to go for. Kinda wish eternal went in that direction in all honesty with it's art. To me it's a side of DOOM that's getting more lost as time goes on, which is ashame. Because now we really have the tech to do that kind of art direction justice.
I just thought. I have yet to see a map created where you face a cyberdemon, and you are forced to pick up the partial invisibility. For example, you get teleported on top of one and forced to face the cyberdemon. Would be an interesting fight.
The engine internally runs at 35 fps, but not all of them may be drawn on screen. 15-20 fps were typically what you get from the hardware of that time.
Command & Conquer has a similar but more elaborate effect on its Stealth Tanks, but, notably, they did _not_ include proper range checking, meaning it will read outside its buffer on the bottom of the screen. But given the lax memory management in DOS, this rarely gave any real issues in the game; it just showed some messy glitchy pixels and that was all. That is, until the Win95 port got re-released on Windows XP, and suddenly _everyone_ was getting these crashes, and community hackers had to figure out how to fix it in the game's bytes.
4:30 - Except in some very old versions of the vanilla engine, in which the pinkies' attack worked like hitscan, and could therefore cause infighting under the right circumstances ;)
at first I thought the video was a joke since the audio played but the video didn't load so I just thought that was the whole joke that the video was "invisible" then I realized that no, youtube is just messing up once more
"The Revenant’s homing missile doesn’t care for your partial invisibility" Makes sense as your are partially invisible in the visible light spectrum while the homing missile would use infra-red radiation to track you.
Fun facts: 1) The easiest way to see the fuzz effect "freezing" is to have partial invisibility, pull out the shotgun, and then decrease the screen size by 1 (so the green border is surrounding the screen). This only applies to the original 320x200 resolution. 2) Heretic's translucency effect incorrectly cuts itself off at the top/bottom of the screen despite not needing to because those lines were erroneously left in as a leftover from the fuzz effect.
I'm always amazed by how Doom was programmed with all the little details that went on with monster behavior and many more things, just next-level for its time.
This is fascinating. Doom truly was inovative for its time, and still manages to amaze even more than 20 years later. That's why it is my favorite game franchise ever.
The first time I played No Rest For the Living, I had issues with the chaingunners in Map 4 being rather effective snipers. That is until I found the secret partial invisibility, and suddenly they weren't such a challenge at all. I can only imagine the evil laughs that were had when placing them everywhere in Dead Simple, though.
I wondered about some stuff about partial invisibility. Like why Demons face different directions from where they shoot. But this also does make me wonder something else. If you were to set the angle offsets of the demons face target angle to be the ones used for projectiles, instead of another random angle offset for the projectiles, if that'd have made the Partial Invisibility much more useful against projectile based monsters, as it would mean you get a slightly clearer idea of where the demons about to shoot. And it doesn't fuck with muscle memory as much. I personally like that idea more then just making partial invisibility prevent demons from seeing you until you do something to alert them.
I had an idea to make a map where dummies pick up partial invis every so often to ensure the player is partially invisible throughout the map rendering circle strafing and other typical gameplay skills much less useful.
Great video! Editing and visuals were on point, love the work you do with getting the in-game footage at various angles and with useful examples. Top quality stuff
I did like in the Brutal Doom version that the invisibility sphere does make it so (most) enemies can't see you if you're quiet but that demons/spectres will still find you regardless as if they were hunting you by smell alone. It was a nice touch
Linguica analyzed the fuzz effect some years ago, concluding that the "stacked darkening" is a bug, and gave us a look at a "fixed" version. (DW post ID: 1335769) A while before that, he also theorized that id were trying to replicate the "warping effect" seen in 80's The Predator, and gave us a look at it too by removing the darkening from the fuzz effect altogether. (DW post ID: 1335541) I tried commenting this a few hours ago, but I guess YT keeps banishing comments with URLs, so I resorted to providing the Doomworld post IDs instead.
Meanwhile in a private boxing ring. BMD: you got to understand you fight great but I’m a great fighter. Decino: you want to ring the bell Apollo? BMD: all right ding ding. Both throw their first punch. It’s the eye of the tiger it’s the thrill of the fight rising up to the challenge of our rival Dwars: so who won the fight? Decino: he did.
The magenta part was interesting, and if it weren't for ports being able to replace the fuzzification with a different transparency method, I'd smell a WAD that _abuses_ this to be as painful as you demonstrated...
TES: Arena; Daggerfall: "It's called *_Chameleon;_* it works best when stationary." Yep, just dropped that reference; *_Illusion sorcery_* is a strange wonder indeed.
I've been on a massive classic DOOM kick, and these mechanic explanation videos are so fascinating to me. Always wondered how that fuzz effect was done :0 Hoping for a video on the DOOM alphas someday. I remember you and Dwars asked Sandy about the dark room with a skybox in E2M7 having a ceiling, and it actually did in the alphas! A lot of skyboxes in Hall-Petersen maps were originally ceilings, actually...
Back in the 1992-1993 when the game was developed, no one played still maturing FPS games by zooming through the maps, strafe running in circles around enemies and spamming rockets all in the same time. Most players used arrows and keyboard only for playing, turning in place and standing during shooting. Then Partial Invisibility had much more sense, as it was crafted for mostly static or not much mobile targets.
Perfect timing, Decino! I was genuinely just playing a level where a blur-sphere was particularly detrimental in a Cyberdemon fight. (Arrival, Map04: Free Press) Maybe this video will help me git gud 🙏🏻
Thanks for another analysis video, we all love them. I know you have covered most of the interesting stuff already, but we would watch you analyse a blade of grass for 20 minutes at this point, they are so well made. Keep up the good work.
I absolutely love this one and generally how you make the process of coding these things really easy to digest, you're really helping preserve the craft
Memories of hopelessly trying to convince your trigger-happy allies that you are not an SSG welding Spectre Demon.
🫂
SSG welding? Would that produce a quad-barrel?
Jokes aside a Pinky with an SSG horrifies me
Oh the memories of doing Eternal DOOM (not to be confused with DOOM Eternal) co-op run in 90s LAN parties. The amount of times the sentence 'oh, it was you? sorry' was uttered...
@@lambda-m1676 The Quad Barrel exists: ua-cam.com/video/UkIgo4AnRdU/v-deo.html
A Specter with an SSG sounds even scarier than a Cyberdemon or the Icon of Sin.
"let's have a look, shall we??"
Uhh, you're partial invisible. I can't look
👀
You can look, but there's a random offset that might make you look away from the screen by 22 degrees.
foiled again!!
You can partially look because they're partially invisible
"Let's partially look a it, shall we?"
I can't believe agonizing rectal pain is gone bros...
pour one out for our man, he finally visited the gastroenterologist
It's a terrible day for rain...
He will live forever in our hearts
Decino is a real one for agreeing to read that one out as many times as he has.
How can we bring Agonizing Rectal Pain back?
Important to note for GZDoom types: You may notice enemies do NOT spot you by default. However, in vanilla, enemies will still spot you through the power-up.
Heretic's Shadowsphere DOES have the GZDoom style mechanic in its vanilla game though!
Also you can turn on the og behavior using the compatibility settings
Honestly always liked the enemies not spotting you with partial invisibility. I began playing on Gzdoom and was disappointed when i moved to other sourceports that didn't have that
Funnily enough, one of the recent GZDoom versions (4.12, but seems to be fixed now) somehow broke angle randomization completely. So you would have enemies attacking you as if you didn't have it.
Also important to note pretty much the whole ZDoom family of ports has this, including ports like Zandronum. The change in behaviour came when ZDoom got Heretic support, because the code for that behaviour from the Shadowsphere was intentionally added to Doom's Blursphere. The early days of advanced Doom ports was a wild west of changing the game's behaviour, keeping the vanilla game as is in more advanced ports largely started with PrBoom and its descendants, with their features like complevels.
If you play around with it in GZDoom you'll notice that sometimes the enemies notice you anyway. They have a random chance of spotting you if you get too close or move too fast, so keep your distance and move slowly (slower than walking speed) and you'll remain hidden for as long as the powerup lasts. This is also taken from Heretic's Shadowsphere.
"why else would you click on the yellow thumbnail?" I don't know man, Sometimes I just wanna listen to the pumpkin man talk
this is true
I love that Doom has this surprisingly in depth implementation for its fuzziness effect, then its RNG table is just 255 random values with no real logic or weighting to it. What a fascinating game
Both groundbreaking and lazy.
Shaders weren't a thing back then (because graphics cards weren't a thing). I played Doom on a 386 (under 40 MHz) for example. That CPU had to do EVERYTHING -- not just collision, player input, and enemy AI but rendering. They simply couldn't do complicated algorithms to mimic shaders outside of table lookups. It is impressive that they accomplished what they did.
@@musaran2 Yep, they were truly lazy back then... Nowadays you need to add a LIGHTING to a SCENE to make shadows appear!
@@eiyukabe Graphics cards of course were a thing. What you meant is that HW/3D acceleration was not a thing
There IS a weighting to the RNG table! It's a rough bell curve with a slight bias towards the high end. Decino has shown plots of it in previous videos.
Fun lore fact Spectres are pinkies with a cacodemon eye put inside of them giving them psionic abilities in doom 2016, if we apply this logic to the classics then the invisibility sphere is a cacodemon eye.
Or a pain elemental eye!
Processing...
Initializing...
New headcanon accepted.
Error...
Cursed thoughts detected.
Are we just chomping down on that powerup, or do we just crush it in our hands to achieve power?
Doom guy eats all of the power ups
Even the armor?
@@BlazingShadowSword Fixing error...
Removing thought...
loading new reason...
he probably just absorbs it
Cannot detect if Error was fixed...
As a kid, I couldn't understand English very much, but I knew what "Invisibility" meant, so when I picked it up and the monsters still saw me, I thought the demons use thermal vision like a Predator or something. Didn't even notice how it works, because I was a stupid child and strafing was something I didn't do at all, so it should have been obvious. Yes, I struggled with the Cyberdemon, how could you tell?
I was precisely the same mate 😅 a very confused kid
Can Maulataur in Heretic be beaten on lowest difficulty skill by using arrow keys only?
With Ring of Invulnerability, yes.
Maybe this is why my mom liked Heretic more.
You should try Heretic, it's easier than Doom I guess.
@@karpai5427
I played Heretic as a kid. It was great.
@@CsubAzUrmedve Szia Csúb! I also started with Heretic, I was like 3 years old when I played it on a Windows xp that didn't had any audio card and I played using the arrows and for slower movement I used the mouse. I love Doom and I'm also planning to make a total conversion Doom mod similar to Ashes and Hedon!
I can relate, but boy what an interesting handicap that could be!
No-strafe runs of certain levels would be super interesting to watch.
i like how the meme sound effects you add in are very subtle unlike the earrape that most other people use
**Baron Fart Ahead**
Vine Boom is one of my most hated sound effects because of this phenomenon.
I never really cared about the partial invisibility powerup until that one map in Plutonia where you pick it up and this huge window opens and you're surrounded by monsters, a lot of them hitscanners. I thought I was done for until the chaingunners opened fire and they missed almost all of their shots. I took the initiative and started cleaning house. That was a pretty memorable fight, and it goes to show that good item placement can really elevate a map, just as much as where a mapmaker places his enemies.
The irony is, in most shooters a blursphere or similar item would be unambiguously good, because you had no chance of dodging all the bullets anyway. You're basically hoping the enemy misses you, so a higher chance of that is never bad. In classic doom (especially nowadays) that's only true for hitscan, or in rare cases where there's just a comical amount of enemies shooting you.
It's an item that makes sense in every fps except the one it's in.
Shrodinger's Power-Up. Works well anywhere but where it is
“The Revenant’s homing missile doesn’t care for your partial invisibility” has the same energy as “The missile knows where it is because it knows where it isn’t”
Makes me think of Star Trek The Undiscovered Country. Specifically the final battle.
"By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), "
The Revenant's homing missile knows where you are at all times. It knows this because it knows where you aren't.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Arthur Conan Doyle
@@garcello3398 "it obtains a difference, or deviation"
I KNEW IT! I KNEW ENEMIES FIRED BACKWARDS!!!! I THOUGHT I WAS LOSING MY MIND!
Baron fart!
baron of smells @@wallyhackenslacker
@@wallyhackenslacker "Translate to English" - I'm dying [laughing] here
@@wallyhackenslacker wtf lmao
@@TheRetarp Baron fart? More like Baron speed! Haha
I dont get jt either.
It's all fun and games until it messes up with your muscle memory and you end up catching a rocket because of it
I'm pretty certain I've seen maps that force you to get a partial invisibility and have to run past a room full of Cybies lobbing rockets at you. Talk about evil.
@@MrDoom8000😂
I HATED the Invisibility power up.
I was already good at dodging rockets 🚀 and fireballs 🔥 but with the Invisibility power up I start to zig and I get hit because I should have zaged.
I end up running into projectiles. Would piss me off with a passion.
i swear at this point i feel like the demons put the blur spheres there on purpose
yeah I just avoid it most of the time cause its easier to just dodge predictble firing pattern. could be good in areas woth not enough room to move around, but thats it. For hitscans, its always good though.
the fuzz effect mechanic has blown my tiny mind
It's a pixel shader before shaders were a thing! Might be a fun little exercise to implement it in GLSL. Maybe I'll give it a shot when I get back to my computer.
its such an underrated example of how genius id is
Imagine how much data should operate PC while running this game. Never before thought about it, till watched this video. And it's huge work was made on dawn or game industry by people, without any ai helps and tricks.
The magenta colour in OG Doom that can be exploited to create frustration must have inspired the purple goo in Eternal, which also causes frustration.
Magenta does have a significance in the works of H.P. Lovecraft that inspired Id Software (at least John Romero and Sandy Petersen), but I'm not sure if the people behind Eternal Doom were familiar with it, at least none of their map names reference any of Lovecraft's works.
@@fisk0 a mysterious color unlike any seen on earth
@@novameowwwone of Lovecraft’s biggest fears, besides the WELSH!
@@mrziiz6893the man’s list of fears would be longer than a CVS receipt
What about the magenta goo in Eviternity, that causes just as much frustration or confusion?
The Revenant missile knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the Revenant missile from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is.
"where it wasn't, it now is."
Which is usually on the back of my head.
@@hutprancer You chose not to pay attention during Pumpkin Man's lessons on sound propagation! You make the noise, you pay the price!
The "eyeball" powerup animation always fascinated me.
Ah, finally, confirmation that enemies can fire backward.
Pretty much reminds me of "Backward Compatible" corruption card
An interesting exercise would be to combine hitscanner attack accuracy data with their rate of fire and get DPS numbers (given the player doesn’t break line of sight the whole time). Could be valuable for mappers who wish to provide tight and precise challenge.
It's hilarious how the level Dead Simple has several partial invisibility spheres but pits you against enemies whom the effects wont benefit you from. It's like even the guys at id didn't even know how they worked
Au contraire! I've always seen them as obstacles you need to avoid.
I need Partial invisibility to leave work
Cautious, your boss has a 37% chance to see you using his own "back to your cubicle" hitscan weapon.
Nah just up your sprint speed by strafing diagonally and get outta there!
SR50--faster than an automobile!
@@Lyne_TaperzCareful - you won't be able to look both ways before crossing the street while doing that.
@@ultralowspekken Also, chances become 55% if the distance between you and your boss are 250 map units, and 74% on 125 map units!
the idea of a power up that scales in power based on how *gaudy the background is* is deeply, deeply hilarious to me. like imagine if a new weapon were to get released in smth like Fortnite or Splatoon or Third Example Of Contemporary Shooter Game With Any Emphasis On PVP, where it has an ability directly correlated with how much *plaid* is in your surroundings. gotta love a weird engine quirk like that. ;P
Curiously enough, this still is an issue in modern games. As an example, some fighting games have banned some characters' alternative costumes because they would remove or hide certain visual cues.
Tournament bans also extend to stages due to visual noise or other issues - IIRC there's a Street Fighter 5 stage (a flying plane) that's banned in organized play because the swaying background can give you motion sickness.
PSX Doom has an interesting quirk where a single Cacodemon has the translucency effect applied to it. Always found that pretty cool.
Yes it replaces the archvile in the turning stairs in map 17 tenements
Yeah, because PSX Doom didn't have a specific entity for invisible Pinkies, so technically there's no specters in PSX Doom, just Pinkies with the translucent flag on applied to the map thing directly. There was also a flag to make any entity subtractive and double their HP, that's how they made the Nightmare Specter, but you can apply that flag to any enemy. There were Nightmare Imps during development but were discarded, there's a magazine scan with a screenshot of one in E2M6, but you can easily make any Imp a Nightmare Imp by enabling the flag on one of them. Barons look pretty neat with that flag too!
That Cacodemon is nicknamed the Cacospectre
even this seemingly "uninteresting" thing has mechanics that are really cool
It's not seemingly "uninteresting" tho?
It's not "seemingly uninteresting" tho?
Hearing tío decino say all those patrons silly names always makes me smile
It's not the same without agonizing rectal pain.
I'm always amazed at the number of tricks that were possible to pull off with Doom's color palette.
Just the other day I saw in a Corridor Crew video that they use yellow text in their thumbnails because it's an eye catching color. But Decino is miles ahead of them
Those are rookie yellow pixel numbers!
Bright primary colors tend to be very hard not to notice. I've even heard that painting your house yellow improves its value.
That's definitely the most annoying thing when you pick up partial invisibility when you've been playing Classic DOOM for so long. You're so used to dodging projectiles and your muscle memory kicks in and you dodge right into their projectile.
Also thanks for showing us the mechanics behind partial invisibility.
"Simple, just don't draw the pixel lmao"
Decino saying lmao has gotta be one of my favorite things in life.
On the Super Nintendo version of Doom, the partial invisibility power actually makes you invisible to monsters. You can walk right in front of them and as long as you’re not inches away they won’t see you. On the SNES the Partial Invisibility sphere is one of the best power-ups in the game. The SNES version had to cut some serious corners but this is one instance they actually improved on the original game.
Yeah, the SNES version was the first one I owned, then playing other formats made me wonder what was broken about the invisibility.
The SNES version did have a couple of interesting aspects with the weapons - I believe the shotgun was just a single shot with a heavy damage multiplier over bullets, making it more like a long rifle, and the BFG worked differently, with a big splash like a souped up rocket launcher. Plus there was a fun bug where the backpack gave you ammo for weapons you didn't have yet and you could trick the game into giving you a single shot with "ghost" weapons by switching and pausing weapons.
The partial invisibility probably works that way on the SNES to compensate for monsters' lack of sprites that aren't front-facing. Which means it's outright impossible to ambush them.
@@NerfPlayeR135 yeah, for sure - it was a very cut down version, but given that it was on a system a lot less powerful than the other ports, it was a bit of an amazing feat to have so much available in the first place
@@BPCRevere SNES Doom was what happened when a miracle-worker has a passion project. That cartridge was so overstuffed with hard work and mad talent that it's a wonder it didn't explode.
Limited Run Games recently announced an improved version of Doom on the SNES!
When you've been playing Doom for 30 years and you think you know everything, decino makes a movie and you learn something new again.
I remember reading a post in the Doomworld forums about someone "fixing" the fuzz effect so it didn't overdark already drawn pixels and it looked extremely cool.
10:09 I'd love to see an analysis video all about the color palette, how it's used, and how some megawads incorporate and use their own color palettes
It was quite a strange experience when I made my friend play Doom for the first time, since when he picked up a partial invisibility he said "This is quite useful for dodging!" I was so taken back I almost jumped out of my proverbial socks.
The thing is that it messes with muscle memory of seasoned players who already know the patterns and dodge instinctively, often preemptively. A new player, on the other hand, tries to avoid incoming fireballs on the fly, reacting as they appear to the new changed angle and it is easier for them since the projectile doesn't fly directly at player.
@@demogorgonzola yeah, i forget that the many many years back i too used to think it was quite useful for dodging projectiles as well
As someone who first played Doom and Doom 2 keyboard only like it was a tank controls survival horror game, I'm sure it helped me quite a bit!
@@mrjerrio1 Ah yes, a keyboard only player, the tales that you all have to tell are harrowing!
Genuinely didn’t know about the top:bottom row pixel quirk, and I try to collect obscure facts about the renderer like that.
It makes me wonder if the fuzz effect could make use of the transparency maps in Boom, or define what row of the palette to use. It’d be pretty cool to have something like a red spectre that’s slightly easier to see but still has that classic slightly janky fuzz going on.
I was so frustrated as a kid because I thought it was supposed to be for a stealth apporach
yeah no, doomguy doesn't do "stealth"
@@simonsoupshark8009 everyone knows that in 2024. But in 2001, a 8 year old me who didn't even know how to read properly had the right to be frustrated
The more you get into decino's yellow thumbnail videos the more you realize what an absolute technical marvel this game was for something in the early 1990s.
Finally, after all these years, I now understand what this really does. Back in the day it always felt like the powerup is broken because enemies still spot and attack you like normal. Never really noticed the weird angle changes and different projectile flight patterns.
Revenant missile are heat seeking. Partial invisibility reduces you visual signature, not your thermal one.
🤓
YELLOW BACKGROUND DETECTED!!!
Thank you for the description, pumpkin man, it cleared up any confusion I had over what “partial invisibility” meant.
Amazing what the DooM founding fathers did back in the day with the technology they had all cooped up in a house. No Scrum or Agile methods needed. Just a handful of talented computer nerds who believed in their project.
Thanks so much for breaking it down for us, decino. These videos make me appreciate DooM and whole lurch forward that videogames did in the 90s even more.
I really like the chill music as it sets a very good learning environment. It's interesting how much RNG is in this game and how it adds up to the complexity we're still looking at today.
It's simple but very complicated once when multiple actors are involved. I guess you could say it's like Chess... but the pieces move around in real time and have to check a 10 page table of values for everything... and one of them has a super shotgun.
I always found it funny once you're good at doom the shadowsphere actually hurts you because you constantly get shots leading your strafe.
I really like how Brutal Doom upgraded it, so you aren't noticed from a distance until you attack.
Wowowow, it never ceases to amaze me how many details I didn't know, despite thousands of hours playing and hundreds of hours in the code. Love this series. ❤ I especially liked your explanation of the color map, and the funky exploits you can use for evil level design, as if randomized offsets wasn't interesting enough. Very well done.
The blursphere is one of those nuanced powerups that mappers don't seem to know how to use to its fullest extent. There are more uses than anti-hitscan protection or extra challenge in a projectile-based arena. For example, a combat puzzle where your movement is restricted so dodging projectiles is harder could benefit much from a blursphere secret before it - not as broken as an invuln but still a big help, similar to the radsuit secret in Stardate 20x6's Vehelits, that makes the last ambush a lot more manageable.
Oh, there's also yet another name for this powerup: Quantum Stone. Credit to Zeppelin Armada for this one.
modern programmers really underestimate indexing into static tables. You can accomplish so much with so little
One of my favourite uses is translucency in the BUILD engine. The games include a 64KB lookup table of all possible pairings of colours in the palette and which entry is the closest match for a 2:1 mix. The nice thing about using a 2:1 mix is that it lets you do two levels of translucency with the one table (four if you count invisible and fully opaque). Look it up one way and get the more-opaque version, and swap the colours being looked up for the less-opaque one. It's not an insignificant amount of memory when the game has to run in 8MB, but it makes enough of a difference visually to be worthwhile.
You could extend the concept with additional tables for more levels of translucency, too. For 8 total levels (including invisible and completely opaque), you'd need tables for 6:1, 5:2, and 4:3. If you wanted to go to 16, then you'd need 14:1, 13:2, 12:3, 11:4, 10:5, 9:6, and 8:7. Beyond that, you'd probably be writing for a system fast enough that you'd no longer be bothering with palettes and working directly in RGB, or using hardware acceleration.
I suffer from Agonizing Corporal Pain whenever a Decino Analysis video ends.
really innovative for a decino video thumbnail to be all yellow with just the item in the top corner.
7:33 Vertical part of projectile collision box starts in the middle of the projectile.
Yes, bottom half of the projectile has no collision.
"Okay invisibility, great for first time players, a fucking curse for veterans, because what it does is makes monsters more inaccurate and they have a harder time hitting you, so muscle memory kicks in and you dodge right into their projectiles"
Civvie 11's video on The Ultimate Doom
0:20 well maybe it's because I missed your analysis commentary so much!
WAIT ANGONIZING RECTAL PAIN IS GONE!
o7
He finally went to the doctor for a colonoscopy
@@decino Well, at least we got one member of the family still there, the possiblity for a family reunion is still possible!
Also I do got a question.
I know you're very unlikely to do anything regarding DOOM 3 because, well it's doom 3 (though I did get it recently, still looking forward to playing it!) But I am curious if you're ever going to tackle the modern doom games a bit more in-depth. More specifically, if you're ever going to tackle DOOM 4. Since more leaks and stuff were found regarding it and it's made me realize just how much of DOOM 4 survived into 2016. Was just curious if that's something you plan on talking about on the channel down the road.
Also loving these videos still! Seeing these quirky things like the effects the magenta room has at the end of the video, and the effect at 12:11 has been inspiring my map designs in other games!
Sorry for the long comment, just a big nerd is all, lol.
I'll be blunt: I have zero interest in Doom 4 and its cut/reused content.
@@decino Fair enough! I am admittedly more interested the horror side of doom and honestly, the art direction of DOOM 4 and 2016. Gameplay wise, I'll be equally as blunt, they're awful. But man, I do love the horror ideas they were trying to go for. Kinda wish eternal went in that direction in all honesty with it's art. To me it's a side of DOOM that's getting more lost as time goes on, which is ashame. Because now we really have the tech to do that kind of art direction justice.
the cyberdemon with the fuzz effect at 9:08 looks awesome
Ah yeah, the thing I get only when I don't need it
I just thought.
I have yet to see a map created where you face a cyberdemon, and you are forced to pick up the partial invisibility.
For example, you get teleported on top of one and forced to face the cyberdemon.
Would be an interesting fight.
Scythe does that.
it's crazy the amount of calculations for different things this game did 30 years ago and it still ran so smoothly (at 35 fps but still)
The engine internally runs at 35 fps, but not all of them may be drawn on screen. 15-20 fps were typically what you get from the hardware of that time.
@@АаронЗильберштейн And I'd bet that 35fps rate is down to it being half the 70Hz refresh rate of VGA.
Command & Conquer has a similar but more elaborate effect on its Stealth Tanks, but, notably, they did _not_ include proper range checking, meaning it will read outside its buffer on the bottom of the screen. But given the lax memory management in DOS, this rarely gave any real issues in the game; it just showed some messy glitchy pixels and that was all. That is, until the Win95 port got re-released on Windows XP, and suddenly _everyone_ was getting these crashes, and community hackers had to figure out how to fix it in the game's bytes.
4:30 - Except in some very old versions of the vanilla engine, in which the pinkies' attack worked like hitscan, and could therefore cause infighting under the right circumstances ;)
Ah, how old the versions?
@@michaelandreipalon359 Think late 1993/early 1994 (i.e. versions 1.0 - 1.2).
at first I thought the video was a joke since the audio played but the video didn't load so I just thought that was the whole joke that the video was "invisible"
then I realized that no, youtube is just messing up once more
"The Revenant’s homing missile doesn’t care for your partial invisibility"
Makes sense as your are partially invisible in the visible light spectrum while the homing missile would use infra-red radiation to track you.
Fun facts:
1) The easiest way to see the fuzz effect "freezing" is to have partial invisibility, pull out the shotgun, and then decrease the screen size by 1 (so the green border is surrounding the screen). This only applies to the original 320x200 resolution.
2) Heretic's translucency effect incorrectly cuts itself off at the top/bottom of the screen despite not needing to because those lines were erroneously left in as a leftover from the fuzz effect.
I have such a strong affectation for downgrades that make you look cooler. Easily a favorite power-up.
rkinkels
0:26 is there an MF_DOOM flag somewhere in the games code ?
I'm always amazed by how Doom was programmed with all the little details that went on with monster behavior and many more things, just next-level for its time.
Amazing, specially the FUZZ part. Never noticed that and really never wondered how it works, thank you for another yellowed video!
This is fascinating. Doom truly was inovative for its time, and still manages to amaze even more than 20 years later. That's why it is my favorite game franchise ever.
The first time I played No Rest For the Living, I had issues with the chaingunners in Map 4 being rather effective snipers. That is until I found the secret partial invisibility, and suddenly they weren't such a challenge at all.
I can only imagine the evil laughs that were had when placing them everywhere in Dead Simple, though.
He’s alive!
I mean, he found some time to make a new video even though he has a kid, thank you!
14:25 Local Florida man found in Decino's credits! More at 11...
I wondered about some stuff about partial invisibility. Like why Demons face different directions from where they shoot.
But this also does make me wonder something else. If you were to set the angle offsets of the demons face target angle to be the ones used for projectiles, instead of another random angle offset for the projectiles, if that'd have made the Partial Invisibility much more useful against projectile based monsters, as it would mean you get a slightly clearer idea of where the demons about to shoot. And it doesn't fuck with muscle memory as much.
I personally like that idea more then just making partial invisibility prevent demons from seeing you until you do something to alert them.
Makes you wonder why the shadow flag wasn't made toggleable like the ambush or difficulty flags on monsters
I'd love to see a full video going in depth about the colourmap and things like diminished lighting
I had an idea to make a map where dummies pick up partial invis every so often to ensure the player is partially invisible throughout the map rendering circle strafing and other typical gameplay skills much less useful.
Might as well just code drunk monsters in mbf21
@@violentbeetle2441 Yes. Let's collaborate on that.
sounds cool, but also extremely frustrating if you aren't very careful with level design lol
Fantastic visualizations as always. Presentation is on point and getting better.
0:25 Completely unrelated, but "MF Shadow" would be the name of an MF Doom / DJ Shadow collab we will sadly never have.
I never thought about how the fuzz effect is rendered. Very interesting indeed.
Honey wake up, new analysis just dropped
12:58 why did you told me about that
Great video! Editing and visuals were on point, love the work you do with getting the in-game footage at various angles and with useful examples. Top quality stuff
Where did bro go? Its like he's *_Partially Invisible!_*
I did like in the Brutal Doom version that the invisibility sphere does make it so (most) enemies can't see you if you're quiet but that demons/spectres will still find you regardless as if they were hunting you by smell alone. It was a nice touch
Linguica analyzed the fuzz effect some years ago, concluding that the "stacked darkening" is a bug, and gave us a look at a "fixed" version. (DW post ID: 1335769)
A while before that, he also theorized that id were trying to replicate the "warping effect" seen in 80's The Predator, and gave us a look at it too by removing the darkening from the fuzz effect altogether. (DW post ID: 1335541)
I tried commenting this a few hours ago, but I guess YT keeps banishing comments with URLs, so I resorted to providing the Doomworld post IDs instead.
Nice workaround, interesting links.
Thanks for the references. It might be fun to port these to DSDA-Doom's OpenGL fuzz shader.
This video was only partially visible to me once i started watching it while i was turned at an angle. Thanks DeCappuccino!
Meanwhile in a private boxing ring.
BMD: you got to understand you fight great but I’m a great fighter.
Decino: you want to ring the bell Apollo?
BMD: all right ding ding.
Both throw their first punch.
It’s the eye of the tiger it’s the thrill of the fight rising up to the challenge of our rival
Dwars: so who won the fight?
Decino: he did.
4:53 this is (probably) a very simple edit, but i found it incredibly satisfying
The magenta part was interesting, and if it weren't for ports being able to replace the fuzzification with a different transparency method, I'd smell a WAD that _abuses_ this to be as painful as you demonstrated...
finally, the king of doom returns to make a video
TES: Arena; Daggerfall: "It's called *_Chameleon;_* it works best when stationary."
Yep, just dropped that reference; *_Illusion sorcery_* is a strange wonder indeed.
I really loved how you covered the real practical ranges because the numbers aren't actually random but pulled from a known table
Y E L L O W
B A C K G R O U N D
It's an amazing brand. You know IMMEDIATELY by the thumbnail when you've got a decino video to click on. 🟨
I've been on a massive classic DOOM kick, and these mechanic explanation videos are so fascinating to me. Always wondered how that fuzz effect was done :0
Hoping for a video on the DOOM alphas someday. I remember you and Dwars asked Sandy about the dark room with a skybox in E2M7 having a ceiling, and it actually did in the alphas! A lot of skyboxes in Hall-Petersen maps were originally ceilings, actually...
Huh, I never knew Spectres' partial invisibility actually effected enemies. Spectres hard counter the Spider Mastermind confirmed.
Back in the 1992-1993 when the game was developed, no one played still maturing FPS games by zooming through the maps, strafe running in circles around enemies and spamming rockets all in the same time. Most players used arrows and keyboard only for playing, turning in place and standing during shooting. Then Partial Invisibility had much more sense, as it was crafted for mostly static or not much mobile targets.
Perfect timing, Decino! I was genuinely just playing a level where a blur-sphere was particularly detrimental in a Cyberdemon fight.
(Arrival, Map04: Free Press)
Maybe this video will help me git gud 🙏🏻
Thanks for another analysis video, we all love them. I know you have covered most of the interesting stuff already, but we would watch you analyse a blade of grass for 20 minutes at this point, they are so well made. Keep up the good work.
New video with yellow thumbnail on feed:
"Aye, Pumpkin Man is back"
I absolutely love this one and generally how you make the process of coding these things really easy to digest, you're really helping preserve the craft
Everyone's favorite "powerup"
Specifically the pumpkin man’s favourite 😏.
Happy 200k, decino! You're absolute unit, big love