Hey. I'm Colin, author of the "Shooting Through Things" article. This is a great video, I like your step by step explanation of the bug. And I like your examples; I was not familiar with the E2M6 corridor, and remember wishing I had a clear example in the original levels at the time. I am pleased and amused that you tracked down the spot in Barrel where I first saw the bug :-) And I did a little update to my article to link to your videos.
Thank you so much Colin. This video would not exist if it wasn't for your original study of the bug, and all it's ramifications and consequences. It's an honor to have my videos linked in such a timeless article! Cheers!
This is incredibly well done and deserves a thousand times more views: amazing visuals, easy to understand, and I learned a lot of new things. Blockmaps always seemed a bit alien to me, but not anymore!
Haha I wasn't even sure what I was watching, I just saw you uploaded natural instinct click here first yeah I'm a simple person who likes life uncomplicated with a few really great things to keep me going through this unholy shitshow called life and your channel is one such thing kiitos.
Despacino, you could mention the block map bug in one of your videos, suggesting the viewers to watch coincident's explanation video, so more people could get to know his work ;) (edit: now I saw Decino posted it on his community tab)
I love that photo of ID software. @9:36 For those that don't know, that was John Romero's door. He had gotten locked in his office, so Carmack took his $5000 battle axe, and chopped the door down while the office cheered him on. The photo is the aftermath of the door.
The phrase “Oh, come on, man! He was right in front of your shotgun!” has always been associated with XCOM but I always thought it might fit in a game like Doom. Now is the time.
In Fallout you can raise accuracy percentage by investing skill points up to 300% but after all the modifiers whatever it turns to be it's hard-capped at 95% making sure that 1 in 20 shot misses. Also if you have good enough armor/perks it is very possible for a player to be shot by enemy with a minigun burst and have it either miss or hit ...for 0 damage. It's even funnier if you have jinxed trait - don't shot back at enemies and all unused action points go into armor class lowering their success chance even more to the point they'll eventually suffer a critical failure and destroy the weapon and/or hurt themselves. :)
I remember finding a quote from John Carmack about his regrets over the blockmap, apparently there was a much faster, simpler, easier, more accurate method of collision detection right in front of him...The BSP! He didn't go into details on how he'd specifically would have used it, but it would have 100% eliminated the blockmap and its associated issues
@@TheExFatal the technique that Doom uses to partition its maps to speed up rendering (can very quickly find where the camera is if you're discarding 50% of the data every step) That speed would have been perfect for quickly finding exactly which wall a collision occurred against (if any).
@Lassi Kinnunen 81 Well, the Pentium 66 had cooling issues. To my understanding, the rejects were downclocked 6mhz and sold way cheaper. Intel wasn't a bunch of crackheads until the 2000's.
It's weird, that what goes on in a game can become treated so seriously, like the results might be published in something like a scientific journal, when it's all built on bugs in a physics engine.
@@expendableround6186 Me neither. And if it breaks demo compatibility, as a non-speedrunner I say "oh well". Blockmap bug is the #1 reason why I don't use the Eternity engine, and haven't completed Heartland to this day.
Thanks for this! Every time I was in chat and ppl said that something was a blockmap issue, I just cluelessly nodded along, but now I know :D Feels good.
I don't understand half of this shit with Doom and I am literally supposed to have the iq of a genius due to aspergers syndrome but fuck me I can be stoopid at times 😂😂😂
This video is waaaaay too good, production quality is high and it's so easy to understand, you are waaay too underrated mister I'm sure you're channel will do great!!
The grid system is funny to me cause it's what Terraria and Minecraft implemented to reduce performance issues due to being large worlds. edit: Your videos makes Doom feel like the game version of The Art Of War. Old ideas but still used and useful still today.
This reminds me of my own solution to 3D collision. I'm using GameMaker Studio, which has built-in 2D collision checks. For collision with enemies/objects, rather than dividing the map into blocks, I use the built-in 2D collision, with extra large 2D colliders to determine what close enough to *possibly* collide (including a buffer zone to avoid fast-moving objects "passing through" other, smaller ones), and once I have that list I perform my own 3D collision checks between those objects manually. As for terrain, it actually is broken up into similar 2D chunks or "blocks". My terrain collision is handled with heightmaps, and I only load the chunks that the player is in, nearby (within a radius of the player), or could teleport to. Moving objects that are active outside the player radius also have their own radius added to this load list. This was all influenced by info I've learned about DOOM, Super Mario 64, and the early Crash Bandicoot and Spyro games. Thanks, RUclipsrs.
OMFG, my mind is blown! It makes absolute sense why it can take more then 3 shots to kill a Cyberdemon with a BFG sometimes. Even when shooting Barons with a SSG, I never understood why sometimes it wouldn't die in 6 shots. I assumed it was RNG with the pellets... I was not aware of this way of collision detection at all. Thanks so much for explaining this in detail!
Even the cross sections are flawed. Large enough enemies will become melee resistant if attacked head on. Sure, with the fist you can just aim diagonally, but with the chainsaw (which locks you onto the enemies center) your only hope is to circle strafe an hope your lucky enough to cross one of the lines. Anything with a radius of over 33 units (66 x 66 bounding box) becomes essentially chainsaw proof. Basically arachnotrons, mancubi, masterminds, and cyber demons can't be chainsawed and can only be punched diagonally. My advice is this: if it's too big to fit through an exist door , it's too big to easily Melee.
Nah.. coincident is really his own unique content creator. He does some really cool classic doom speed run with commentary if you haven’t checked that out. But anyway, both are great in their own way.
Source port quirks are much more benign and easier to put up with than a bug that makes shots phase through the enemy.The latter is akin to _tripping_ in that it renders your inputs useless.
Whoa...this was absolutely fascinating! You my friend have a brand new subscriber and an upvote! I remember when Doom came out in 1993 and to be honest...we didn't care that it had bugs. It was a true game changer and what first introduced me into the world of PC gaming. In late 1994 my parents decided they had enough of me trying to find a way to play Doom on a console and be happy with it. My dad helped me build a 486DX2@66Mhz and it ran Doom quite well.
I've gotta say, the visuals and editing on this video are great and really help to keep it interesting and clear to understand, great job. I'm surprised you don't have more subs
This video is masterclass with all of the illustrations. I have a feeling this was a very complex issue to understand and figure out how to present clearly, but the result is so good that I never once felt confused. The whole time I kept thinking I could never make something like this and wondering how people put together videos like this. Then at the end, you said it took you six months, and I thought, "Oh, that's how: tons of time and effort."
So glad you got into the potential of a player using it to their advantage and potential applications in deathmatch - two things I was wondering about during the first half. Seems pretty unlikely to be practical as a DM strat. Fantastic vid!
What a well-put video coincident, I never understood 100% the blockmap bug, now I do. I hope you can do this kind of video eventually, tho I know it is a heck of work...
Wow that explains why sometimes my punches or chainsaws miss even tho I'm point blank and dead center on the monster. Also explains why sometimes it takes 2 bfg blasts to kill a cyberdemon and sometimes 6+. Almost 30 years after release and we're still learning new things in Doom.
Six months for one video, that takes serious chops. Thank you for your dedication. The extra time you took getting all the visualizations and examples right definitely made such an esoteric concept easier to understand. If you'd just tried to brute force the explanation, I think this video would have been boring and frustrating instead of entertaining and informative.
I've written a lot of blockmap generation code in ZokumBSP. The blockmap bug also affects monsters. One of my tests were a Doom 2 nm run by Henning Skogstø. The player would actually die on map02 due to taking more damage from shotgunners than intended IF the origin of the blockmap was moved. So if the goal is to avoid monsters and just get to the exit, the blockmap bug and moving alongside the block edges can reduce incoming damage from hitscan enemies. These tend to be the real killers in most speed runs as projectiles are dodgable. Nightmare is substantially harder with perfect collission detection due to the added damage in some areas. I did manage to create "perfect" id compability blockmaps in the end. Some bugs led to desyncs on one map where the player would still exit, and then died on the next map. This took me a while to figure out since it was also a bit into the run :). If you're a mapper and you're annoyed with a key section having buggy blockmap behaviour, ZokumBSP can have a custom origin point, allowing the mapper to decide where the grid lines up. This could of course make other areas problematic, so one might have to compromise a bit no matter what for some layouts. If you're interested in blockmap hackery, check out Block Rocking Bytes: doomwiki.org/wiki/Block_Rocking_Bytes There are also several other blockmap related bugs. The 0000 header problem being one of them, faulty collission detection at low speed is another.
Thank you for the comment. That was very insightful. For any mappers looking at this and wanting to move the blockmap around, make sure to check ZokumBSP (if you haven't already): doom2.net/zokum/zokumbsp/
Bro, since Decino there has not been any other guy to present Doom's technical details and stuff in a comprehensible, entertaining and fun way!!! Keep it up :3
Judging by the other stuff on this channel, it was hard to imagine the same person narrating an analysis video, but your narration was actually great. Very good use of visuals to illustrate concepts too.
This explains why the chainsaw and punch points you to the target center on hit: To increase the chance of hitscan being on the right blockmap and reduce corner cases
Funny thing, the first time I heard of the blockmap wasn't this video. It was in a book titled "Game Engine Black Book: DOOM", where proceeding it was an anecdote about how after DOOM's release John Carmack found out from Bruce Naylor, basically the foremost authority on BSP trees, that the BSP tree used to render Doom's geometry could also have been used for collision detection, eliminating the need for the blockmap entirely. If this had been found out earlier, when Carmack was coding the engine, this bug wouldn't even exist.
What a coincidence. Yesterday I ressurected old Pentium PC with original Doom 1 on it and experienced this bug. And today I recieved perfect explanation on it. Great video! Thanks!
And one more thing related to Doom.Since there is no recoil of in any weapon in doom the sprites for any weapon that has hit scan spread,so basicly the closer you shoot with the shotgun the bigger concentration of sprites and further targets get hit with the less concentrated sprites of a shotgun.Also chaingun has sprites and it has the same rule goes for the pistol so further you shoot with those weapons the less concentration of sprites there is but still there is a chanece to hit an enemy further away from you with even with using the pistol.
I had no idea this was a thing until Decino mentioned it and your channel in a video. It explains a lot though, I often wondered why obvious hits didn't count sometimes.
Great video! Ironically, as pointed out in Fabien Sanglard's " Game Engine Black Book DOOM," Carmack could have just used the same BSP tree already in place for quick rendering instead of blockmap for collision detection, but it didn't occur to him at the time.
Yes! Finally! I waited for this video for quite a lot of time. I'm so happy to see that it gave you a huge boost of viewers and subscribers, I think you bring the best DOOM content to RUclips these days, and I really hope that it will give you motivation to increase your activity and bring us some more cyan videos and awesome speedruns :)
Source port quirks are much more benign and easier to put up with than a bug that makes shots phase through the enemy. The latter is akin to _tripping_ in that it renders your inputs useless.
just the fact that the blockmaps are communicated to the player on the map was something I never really knew. But I pretty much only used ZDoom (and by extension GZdoom, Skulltag, and Zandronum) so I was rarely if ever affected by it.
I had to face the problem of slow collision detection more than once. When the double-barreled shotgun makes the game pause for half a second, that algorithm is too slow. Of all the fixes I contemplated (including the one I eventually implemented), none were as... interesting at this one, let's say. Fascinating to see how this works though, and here I thought John Carmack was the smartest person to ever live excepting that wheelchair bloke with the robot voice.
Decino pretty much said what I wanted to say. This is a well crafted video that explains the inner workings of a game. I'm a sucker for these kinds of videos whether it's breath of the wild, pacman or doom
Fascinating video - I love learning about odd technical stuff like this in games, and you explained it really well here; the animations really help with illustrating the bug. This deserves way more views, keep up the great work!
This is some really good explanation. I really like how you took the time to explain in deep what it's this bug, specially the benefits about dividing the map entirely by squares. Great job! I'll be looking forward to see more content.
When I started playing Doom in 1994 I eventually upgraded my machine to a 486DX2-50 (DX2-66 was too expensive for my budget) a Pentium CPU was positioned and priced for server computing so as a university student it was totally out of my mind. I used to sell machines to friends and family so I got my hands on a DX2-66 CPU and was elated, so when I had to finally swap in my own DX2-50 I forgot to set the myriad of jumpers in the motherboard to put it back in DX2-50 mode so even though at first I didn’t notice it my DX2-50 was overclocked into a DX2-66. Eventually I got to play and noticed the speed bump, at first I thought I could burn the CPU but after much testing I eventually left it at DX2-66 and was SOOO HAPPY! I also used to play with a friend over 2400 modem with reasonable performance and it was a blast! Much better was when we had the chance to get together at another’s student house with another friend and after studying was over we could play Doom over a 10 base 2 lan we setup for the weekend. It was totally awesome thought the studying suffered a bit LOL! I eventually sold my machine as a DX-66 and never got a complaint from the buyer :)
I read the article in question in early 2020 or so, but still it was a nice explanation! Killing one of the two pinkies in that way sounds like a great way to use the bug.
Hey. I'm Colin, author of the "Shooting Through Things" article. This is a great video, I like your step by step explanation of the bug. And I like your examples; I was not familiar with the E2M6 corridor, and remember wishing I had a clear example in the original levels at the time. I am pleased and amused that you tracked down the spot in Barrel where I first saw the bug :-)
And I did a little update to my article to link to your videos.
Thank you so much Colin. This video would not exist if it wasn't for your original study of the bug, and all it's ramifications and consequences. It's an honor to have my videos linked in such a timeless article! Cheers!
I'm extremely racist
This is incredibly well done and deserves a thousand times more views: amazing visuals, easy to understand, and I learned a lot of new things. Blockmaps always seemed a bit alien to me, but not anymore!
Haha I wasn't even sure what I was watching, I just saw you uploaded natural instinct click here first yeah I'm a simple person who likes life uncomplicated with a few really great things to keep me going through this unholy shitshow called life and your channel is one such thing kiitos.
Thanks again decino! I'm glad I can spread some knowledge.
Despacino, you could mention the block map bug in one of your videos, suggesting the viewers to watch coincident's explanation video, so more people could get to know his work ;)
(edit: now I saw Decino posted it on his community tab)
I didn't get here through your YT community post, YT recommended it to me in the feed, but ty.
Despacino! 😂
I love that photo of ID software. @9:36
For those that don't know, that was John Romero's door. He had gotten locked in his office, so Carmack took his $5000 battle axe, and chopped the door down while the office cheered him on. The photo is the aftermath of the door.
Ahahah that's awesome. I didn't know that. 🙂
Id software is so goddamn dank
That is amazing!
Whats even better is that its because John Romero locked himself in his office to play DooM. God i love 1993 Id software
man your channel is incredibly underrated
Both of your channels are underrated! You both are awesome in your own ways
can we have doom 2021 experience
Nope. Undiscovered, not underrated.
Man
Criminally underrated
If ahoy and decino had a love-child...
Well compared.
That is so true.
Lmao
This comment is so underrated lmao
I mean, the best of two worlds
The phrase “Oh, come on, man! He was right in front of your shotgun!” has always been associated with XCOM but I always thought it might fit in a game like Doom. Now is the time.
In Fallout you can raise accuracy percentage by investing skill points up to 300% but after all the modifiers whatever it turns to be it's hard-capped at 95% making sure that 1 in 20 shot misses.
Also if you have good enough armor/perks it is very possible for a player to be shot by enemy with a minigun burst and have it either miss or hit ...for 0 damage. It's even funnier if you have jinxed trait - don't shot back at enemies and all unused action points go into armor class lowering their success chance even more to the point they'll eventually suffer a critical failure and destroy the weapon and/or hurt themselves. :)
@@demogorgonzola no joke, I got a critical failure with the starting 10mm pistol while shooting the first couple of rats in the cave
Psychotherapist: "Three-armed Doom Guy isn't real. He can't hurt you."
Three-armed Doom Guy: 10:35
I remember finding a quote from John Carmack about his regrets over the blockmap, apparently there was a much faster, simpler, easier, more accurate method of collision detection right in front of him...The BSP! He didn't go into details on how he'd specifically would have used it, but it would have 100% eliminated the blockmap and its associated issues
What's the BSP?
@@TheExFatal the technique that Doom uses to partition its maps to speed up rendering (can very quickly find where the camera is if you're discarding 50% of the data every step)
That speed would have been perfect for quickly finding exactly which wall a collision occurred against (if any).
Binary Space Partitioning. Basically, your environment can be dumbed down to a binary tree. It’s an easy way to store information about real spaces
I think this may have been about the reject table, not the blockmap. Carmack realized later that BSP would've handled reject table's job.
So this is why decino missed many pistol shots on a Shotgunner in his Plutonia outtakes video.
And this is why John Carmack is one of the most brilliant minds we have in gaming. At least in coding aspects. Pulling this off in 1993 is astounding
He was absolutely awful with Running Id, but he was young
The first pentium was actually 66mhz, the 60mhz Pentium was created later on and was released on the same day as the 66mhz.
Whether 60 or 66, the Pentium really dished out some megahurts to the math calculations for Doom....
....
😆
@Lassi Kinnunen 81 Well, the Pentium 66 had cooling issues. To my understanding, the rejects were downclocked 6mhz and sold way cheaper. Intel wasn't a bunch of crackheads until the 2000's.
@Lassi Kinnunen 81 Well. they had to. Otherwise it was just a waste of money, materials and time.
what
@@allcapsdown lemme guess. You’re from Gen Z?
WHY THE HELL DIDN'T ANYONE TELL ME THIS BACK IN 1994?!
Because you had to ask Carmack himself ;-)
I feel like I'm watching a National Geography documentary about Doom, the videos are getting better and better :) also rip many uv max runs.
It's weird, that what goes on in a game can become treated so seriously, like the results might be published in something like a scientific journal, when it's all built on bugs in a physics engine.
I’m not enough of a DOOM purist to say that fixing bugs like this is a bad thing, _because it’s not._
@@expendableround6186
Me neither. And if it breaks demo compatibility, as a non-speedrunner I say "oh well".
Blockmap bug is the #1 reason why I don't use the Eternity engine, and haven't completed Heartland to this day.
Thanks for this! Every time I was in chat and ppl said that something was a blockmap issue, I just cluelessly nodded along, but now I know :D Feels good.
Glad I could help 🙂
I don't understand half of this shit with Doom and I am literally supposed to have the iq of a genius due to aspergers syndrome but fuck me I can be stoopid at times 😂😂😂
God the amount of times I’ve tried to chainsaw a pinky and I somehow didn’t kill it. Thank you for this explanation!
This video is waaaaay too good, production quality is high and it's so easy to understand, you are waaay too underrated mister I'm sure you're channel will do great!!
Thanks for the compliment! Glad you enjoyed it.
Decino sent me here.
This is like the smol d man's analysis vid but the wall is light blue
Doom Analysis with a solid color background, name a more iconic duo.
For real tho, solid content, keep it up!
The grid system is funny to me cause it's what Terraria and Minecraft implemented to reduce performance issues due to being large worlds.
edit: Your videos makes Doom feel like the game version of The Art Of War. Old ideas but still used and useful still today.
Very underrated detail, but I love how you use the cyan color for background - in Doom, it's the color id used for transparency
This is some top tier analysis video, very similar to decnio’s stuff, I love it ! this deserves thousands of views!
This reminds me of my own solution to 3D collision. I'm using GameMaker Studio, which has built-in 2D collision checks. For collision with enemies/objects, rather than dividing the map into blocks, I use the built-in 2D collision, with extra large 2D colliders to determine what close enough to *possibly* collide (including a buffer zone to avoid fast-moving objects "passing through" other, smaller ones), and once I have that list I perform my own 3D collision checks between those objects manually.
As for terrain, it actually is broken up into similar 2D chunks or "blocks". My terrain collision is handled with heightmaps, and I only load the chunks that the player is in, nearby (within a radius of the player), or could teleport to. Moving objects that are active outside the player radius also have their own radius added to this load list.
This was all influenced by info I've learned about DOOM, Super Mario 64, and the early Crash Bandicoot and Spyro games. Thanks, RUclipsrs.
OMFG, my mind is blown! It makes absolute sense why it can take more then 3 shots to kill a Cyberdemon with a BFG sometimes. Even when shooting Barons with a SSG, I never understood why sometimes it wouldn't die in 6 shots. I assumed it was RNG with the pellets...
I was not aware of this way of collision detection at all. Thanks so much for explaining this in detail!
So when are we getting Doom explanation videos with bright magenta thumbnails? We already have yellow and cyan
Even the cross sections are flawed. Large enough enemies will become melee resistant if attacked head on. Sure, with the fist you can just aim diagonally, but with the chainsaw (which locks you onto the enemies center) your only hope is to circle strafe an hope your lucky enough to cross one of the lines. Anything with a radius of over 33 units (66 x 66 bounding box) becomes essentially chainsaw proof. Basically arachnotrons, mancubi, masterminds, and cyber demons can't be chainsawed and can only be punched diagonally. My advice is this: if it's too big to fit through an exist door , it's too big to easily Melee.
I'm honestly not sure if this isn't just decino doing a funny voice, awesome work man. Subscribed.
This mans is literally Decino 2
Decino 2: Hell on Earth
@@HOWLWOLF Heck*
Rerere hi hahaha
@@HOWLWOLF Don't watch his 21st upload, I hear it really sucks. 😋
Nah.. coincident is really his own unique content creator. He does some really cool classic doom speed run with commentary if you haven’t checked that out. But anyway, both are great in their own way.
This video is near perfection to me, the only info that I missed from it is how some of the sourceports fixed this bug.
Awesome video.
Source port quirks are much more benign and easier to put up with than a bug that makes shots phase through the enemy.The latter is akin to _tripping_ in that it renders your inputs useless.
@@expendableround6186 I'm aware. I just wanted to see him show how the programmers who made the sourceports fixed the issue.
Whoa...this was absolutely fascinating! You my friend have a brand new subscriber and an upvote! I remember when Doom came out in 1993 and to be honest...we didn't care that it had bugs. It was a true game changer and what first introduced me into the world of PC gaming. In late 1994 my parents decided they had enough of me trying to find a way to play Doom on a console and be happy with it. My dad helped me build a 486DX2@66Mhz and it ran Doom quite well.
I love your video style! It reminds me of the channel named Ahoy, and I can tell you’re going to be one of my favorite channels down the line
Same here. I love it already.
I've gotta say, the visuals and editing on this video are great and really help to keep it interesting and clear to understand, great job. I'm surprised you don't have more subs
Much appreciated!
Thanks for the effort of making this one. It demonstrated the whole thing very clearly from a very basic way that everybody could understand.
The application of this glitch that you used in that Zone 300 map was brilliant. A month and a half late, but fantastic video.
Thank you!
This video is masterclass with all of the illustrations. I have a feeling this was a very complex issue to understand and figure out how to present clearly, but the result is so good that I never once felt confused.
The whole time I kept thinking I could never make something like this and wondering how people put together videos like this. Then at the end, you said it took you six months, and I thought, "Oh, that's how: tons of time and effort."
Loved the video, and i can tell you put a lot of work into it :)
Thanks a lot Starduster! Yep, this video was a lot of work. I'm wishing I could create more analysis videos quicker, but it's not easy.
The moment the grid was mentioned, I already had an idea on what the bug was going to be. That’s large grid-blocks in old games for ya.
So glad you got into the potential of a player using it to their advantage and potential applications in deathmatch - two things I was wondering about during the first half. Seems pretty unlikely to be practical as a DM strat. Fantastic vid!
What a well-put video coincident, I never understood 100% the blockmap bug, now I do. I hope you can do this kind of video eventually, tho I know it is a heck of work...
You managed to combine both decino and Ahoy in the way you made this video! That's impressive!
This has burned me more times then I care to remember. Very informative video Coincident!
Thank you!
Wow that explains why sometimes my punches or chainsaws miss even tho I'm point blank and dead center on the monster. Also explains why sometimes it takes 2 bfg blasts to kill a cyberdemon and sometimes 6+. Almost 30 years after release and we're still learning new things in Doom.
Six months for one video, that takes serious chops. Thank you for your dedication. The extra time you took getting all the visualizations and examples right definitely made such an esoteric concept easier to understand. If you'd just tried to brute force the explanation, I think this video would have been boring and frustrating instead of entertaining and informative.
That's great to know! Thank you 🙂
I gotta thank decino for recommending this channel.
Instant sub .
It's cool to see this explained in such a clear and easily digestible way; thanks for making this helpful video!
I've written a lot of blockmap generation code in ZokumBSP. The blockmap bug also affects monsters. One of my tests were a Doom 2 nm run by Henning Skogstø. The player would actually die on map02 due to taking more damage from shotgunners than intended IF the origin of the blockmap was moved.
So if the goal is to avoid monsters and just get to the exit, the blockmap bug and moving alongside the block edges can reduce incoming damage from hitscan enemies. These tend to be the real killers in most speed runs as projectiles are dodgable. Nightmare is substantially harder with perfect collission detection due to the added damage in some areas.
I did manage to create "perfect" id compability blockmaps in the end. Some bugs led to desyncs on one map where the player would still exit, and then died on the next map. This took me a while to figure out since it was also a bit into the run :).
If you're a mapper and you're annoyed with a key section having buggy blockmap behaviour, ZokumBSP can have a custom origin point, allowing the mapper to decide where the grid lines up. This could of course make other areas problematic, so one might have to compromise a bit no matter what for some layouts.
If you're interested in blockmap hackery, check out Block Rocking Bytes: doomwiki.org/wiki/Block_Rocking_Bytes
There are also several other blockmap related bugs. The 0000 header problem being one of them, faulty collission detection at low speed is another.
Thank you for the comment. That was very insightful. For any mappers looking at this and wanting to move the blockmap around, make sure to check ZokumBSP (if you haven't already): doom2.net/zokum/zokumbsp/
Bro, since Decino there has not been any other guy to present Doom's technical details and stuff in a comprehensible, entertaining and fun way!!! Keep it up :3
Judging by the other stuff on this channel, it was hard to imagine the same person narrating an analysis video, but your narration was actually great. Very good use of visuals to illustrate concepts too.
Thanks!
This explains why the chainsaw and punch points you to the target center on hit: To increase the chance of hitscan being on the right blockmap and reduce corner cases
I came because of decino, and damn i love it. You explain very well and i really like your voice
Was waiting for some specific timer for few minutes on other game, come to YT to kill a bit of time, let's just say I've missed it :). Great video
I love in-depth and niche Doom videos. Great work, the illustrations were worth the wait. Looking forward to more!
Thank you; glad you enjoyed this. These can take a while to get done, but there are plans for more in the future.
Fascinating - and considering decino is also praising you then you've got a 'subscribed' from me!
This was a wonderfully made presentation of the blockmap bug.
Funny thing, the first time I heard of the blockmap wasn't this video.
It was in a book titled "Game Engine Black Book: DOOM", where proceeding it was an anecdote about how after DOOM's release John Carmack found out from Bruce Naylor, basically the foremost authority on BSP trees, that the BSP tree used to render Doom's geometry could also have been used for collision detection, eliminating the need for the blockmap entirely.
If this had been found out earlier, when Carmack was coding the engine, this bug wouldn't even exist.
What a coincidence. Yesterday I ressurected old Pentium PC with original Doom 1 on it and experienced this bug. And today I recieved perfect explanation on it. Great video! Thanks!
Less than two thousand subscribers for videos like this is absolutely criminal. Glad to be aboard!
I have played a lot of doom and I had no idea this bug even was a thing. Very interesting video.
Another narrating doom player and analyst. Beautiful!
Nice video! I've always wondered about this phenomenon, now it makes much more sense.
One time in e4m1, I ran out of ammo completely, there’s no chainsaw in that level. I had to kill a baron with the fists. It sucked
And one more thing related to Doom.Since there is no recoil of in any weapon in doom the sprites for any weapon that has hit scan spread,so basicly the closer you shoot with the shotgun the bigger concentration of sprites and further targets get hit with the less concentrated sprites of a shotgun.Also chaingun has sprites and it has the same rule goes for the pistol so further you shoot with those weapons the less concentration of sprites there is but still there is a chanece to hit an enemy further away from you with even with using the pistol.
I play a fair bit of Morrowind so I'm used to missing attacks
Bloody Cliff Racers!
@@sugaryhull9688 flashbacks...
I had no idea this was a thing until Decino mentioned it and your channel in a video. It explains a lot though, I often wondered why obvious hits didn't count sometimes.
It's impossible for programmers of the ID soft calibre to not realize this edge case 2 minutes after they design the collision detection system.
Edge and rare case, solution would make game slower, maybe?
All the effort into making this video really payed off! Amazing content.
Great video! Ironically, as pointed out in Fabien Sanglard's "
Game Engine Black Book DOOM," Carmack could have just used the same BSP tree already in place for quick rendering instead of blockmap for collision detection, but it didn't occur to him at the time.
Hey, I like your vids. I know I'm late to the party on this one but I found your shorts through decino's channel and stuck around to see more. Cheers!
You're not late; the party is still going 😎 Welcome!
You triggered my PTSD ,for I had to calculate time complexities for algorithms this year for my uni.
This was awesome, dude. Glad to have caught it, I always love seeing technical breakdowns of Doom.
Yes! Finally! I waited for this video for quite a lot of time. I'm so happy to see that it gave you a huge boost of viewers and subscribers, I think you bring the best DOOM content to RUclips these days, and I really hope that it will give you motivation to increase your activity and bring us some more cyan videos and awesome speedruns :)
Thank you Yo Ya! These take a while to be made. But rest assured, there are more plans for more cyan videos in the future.
I’ve been blessed by the RUclips reccomended feed! This was a very interesting and informative video!
Nice. The animated examples were helpful and they looked good. Clearly a lot of work went into this video.
Source port quirks are much more benign and easier to put up with than a bug that makes shots phase through the enemy. The latter is akin to _tripping_ in that it renders your inputs useless.
Came from a Decino post.
This is awesome dude. Liked this video and subscribed for more videos like this.
This is of great quality ! And I think it also answers why I was having some issues with some actors while modding for Doom in a specific map
amazing video, looking at this seems like this was quite common bug. I wonder why they didn't took level designer into account knowing its bug
Thanks for the video. I needed a refresher on the theory. Well made.
just the fact that the blockmaps are communicated to the player on the map was something I never really knew. But I pretty much only used ZDoom (and by extension GZdoom, Skulltag, and Zandronum) so I was rarely if ever affected by it.
Came courtesy of decino. Staying for great and well presented content.
I had to face the problem of slow collision detection more than once. When the double-barreled shotgun makes the game pause for half a second, that algorithm is too slow.
Of all the fixes I contemplated (including the one I eventually implemented), none were as... interesting at this one, let's say. Fascinating to see how this works though, and here I thought John Carmack was the smartest person to ever live excepting that wheelchair bloke with the robot voice.
Decino pretty much said what I wanted to say. This is a well crafted video that explains the inner workings of a game. I'm a sucker for these kinds of videos whether it's breath of the wild, pacman or doom
Incredible video sir! Well animated, structured, interesting, and well explained.
Thank you kindly!
Fascinating video - I love learning about odd technical stuff like this in games, and you explained it really well here; the animations really help with illustrating the bug.
This deserves way more views, keep up the great work!
Thank you. Glad to know the animations help; the work was not in vain!
Excellent video; thanks for making this. Liked and subbed. Cheers!
That's awesome, welcome aboard 👍
I dont understand how such a video can have dislikes 😔
Cool video i came from Dwars Channel community post xD! And btw you got a new subscriber
Nice! Welcome aboard :)
A good RUclips recommend today. I watch decino for analysis stuff, so this is right up my alley.
Great video and really informative !
I really liked your detailed informations and graphics, they helped simplify everything a bit
Animations and all the visuals helps undersrtand a lot. Subscribed.
Really glad I found this channel.
I always just thought I was too close or something stupid this makes so much sense
This video is very good. You deserve more recognition! good content
Very informative video. We’re always learning new things about these old games!
Extremely well done and expertly narrated. Subscribing now before this channel blows up.
Thank you and welcome aboard!
JetBrains CLion looks nice ;-)
This video is outstanding!
This is some really good explanation. I really like how you took the time to explain in deep what it's this bug, specially the benefits about dividing the map entirely by squares.
Great job! I'll be looking forward to see more content.
When I started playing Doom in 1994 I eventually upgraded my machine to a 486DX2-50 (DX2-66 was too expensive for my budget) a Pentium CPU was positioned and priced for server computing so as a university student it was totally out of my mind. I used to sell machines to friends and family so I got my hands on a DX2-66 CPU and was elated, so when I had to finally swap in my own DX2-50 I forgot to set the myriad of jumpers in the motherboard to put it back in DX2-50 mode so even though at first I didn’t notice it my DX2-50 was overclocked into a DX2-66. Eventually I got to play and noticed the speed bump, at first I thought I could burn the CPU but after much testing I eventually left it at DX2-66 and was SOOO HAPPY! I also used to play with a friend over 2400 modem with reasonable performance and it was a blast! Much better was when we had the chance to get together at another’s student house with another friend and after studying was over we could play Doom over a 10 base 2 lan we setup for the weekend. It was totally awesome thought the studying suffered a bit LOL! I eventually sold my machine as a DX-66 and never got a complaint from the buyer :)
Glad decino mentioned you hope to see good content come from you soon!
I read the article in question in early 2020 or so, but still it was a nice explanation! Killing one of the two pinkies in that way sounds like a great way to use the bug.