Investigating ways to Crash Half-Life 2
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- Опубликовано: 20 июн 2024
- 0:00 Vortigaunt zapping an explosive barrel
1:28 Metrocop standing on an airboat
2:04 Throwing a weapon after it was picked up
3:41 Hallway that deletes you
5:11 Rapidly approaching helicopter 
Игры
At 1:26 there used to be an explanation of why null pointers cause crashes, but it was greatly oversimplified. Cutting that out means the joke at the end no longer makes sense lol.
FAQ
Q: Where code?
A: github.com/ValveSoftware/source-sdk-2013/
Q: UH ACTUALLY you can check if a pointer is null before dereferencing it!
A: I know.
Corrections
1:23 It's not the game that no longer has the data, just the vortigaunt that no longer has it. This is clarified later but perhaps I should've done it right then and there instead.
ok
@@user-zt3hc5qj2u I agree
try getting that to compile using todays visual studio
@@NoahGooder pretty sure it's been done
@@Pinsplash well I guess i need todo better research I just remember needing to play what amounted to visual studio musical chairs where I had to uninstall all versions of visual studio and install them oldest first at the time.
you basicly had to install 2013 then 2014 then 2016 etc
"It removes you"
that is the most intimidating crash report I have ever heard.
you can look in the corner and see his health drop to 0
"Hey, thank you for submitting a report! That should not be happening."
Sounds like some Scp shit
I really enjoy this more technical style of video that includes debugging. Not enough channels that cover glitches and trivia are able or willing to dive in to code.
TheZZAZZGlitch does some super interesting technical content like this about pokemon (mainly gen 1 and 2), would recommend, they make some of the best content on youtube imo
Retro Game Mechanics Explained is another good channel along those lines
You sneaky bastard!
You commented about not being able to find technical breakdowns of glitches so that you could get recommendations for channels where they do technical breakdowns of glitches!
Speaking of, shounic is a good channel for this kind of content.
He makes videos on TF2, the other, other source spaghetti game made by valve. Given the nature of the game, he tends to put a little bit of humor into his videos, even if the joke is relegated to the thumbnail.
Apparently the game also crashes if a barnacle tries to pick up a poison zombie.
the game also crashes when niko wants to go bowling
bruh my youtube crashed when i clicked your pfp
or a rollermine
@@Blurns one of the reasons taking dog's ball to the end of the game is hard
And that one is intentional, I believe.
1:40 I have looked into this, and it turns out what happens is when the metrocop fires his bullet, for some reason the end position of the bullet becomes infinity on all 3 axes, causing the tracing code to be stuck in an infinite loop due to how it internally uses voxels to find objects along a ray. I am not too familiar with how the trace system works internally with the voxels, but I think it tries to find a voxel using a hash of a 3D position (in this case infinity) and fails every time.
Stormtrooper aim
imagine getting shot by a person 17 galaxies away
god i could seriously watch a whole hour of this kind of technical breakdown to why any bug or crash happens.
Glitch Pokémon would be best watch.
@@TheQuestionInAnswer This would be a good suggestion but I've already watched all of that, too 😭
4:10 Haha! I realized the player got removed as soon as I saw the camera do that. I'm sure you know of the command impulse 203, which removes the object you're looking at, well, in TF2, another player can remove you without a crash with the command, which causes you to be put in a limbo state of being in the server and not, brings me back to when I used to hang out on empty private TF2 servers with my friends years back. Sorry for the slightly off topic anecdote, it was just fascinating seeing the same visual occur, fantastic and educational video.
oh, that explains this one time when a server admin was pissed at me because my voice was high pitched because I was still a kid and the same thing happened.
I have good memories of using Ent_delete on people in portal 2 multiplayer which WOULD crash the game iirc
@@painting4850 lmao
Man got sent to the backrooms@@Axodus
that last null pointer crash with the fixme comment legitimately feels like something i'd see in the TF2 source code leak's comments
I mean, they are both Valve games, so very similar pasta dishes being made in the code department.
I am pretty sure that shounic made a video about comments just like the "fixme" comment in the tf2 source code
Valve don't clean up their code very well, HL2 included. The Sniper has an unfinished and unused penetration mechanic lying around and the Strider is still waiting on a proper right leg stomp animation with commented out bits for stomping with the right foot sometimes. (The Strider model does have a right stomp anim, but it's more of a placeholder. It does not mesh with their inverse kinematics and does not return into the idle position, ending immediately on hit.)
@@beingsactual Oh yea Strider stomp was looking so nice in the e3 demo !!
@@MolkoKillStyle The whole Strider stomp mechanic is executed on an impressive level. It uses a smooth animation in conjunction with continuosly running inverse kinematics, temporarily takes over the left foot IK to manually designate it a new target so the Strider aims directly at the victim and then uses ragdoll trickery with an attacment point on the model to do the impaled corpse. The only caveat is that the Strider can only do this with the left foot, despite being originally intended to be able to use either front foot for it. I guess Valve just decided it wasn't worth the hassle, making a right stomp anim and revisiting the code to fully implement the choice of attack, seeing how Striders rarely engage multiple humanoids up close at once in HL2.
The Strider as a whole is a technological marvel of Source capabilities and ingenuous spaghetti code. I mean, they aren't even a ground unit - they're technically a flying NPC using a lot of physics and animation trickery to convincingly sell the illusion of being a hulking stomper.
That last one was so hilarious. "//TODO: Fix Me" on an assert made to correct something that crashes the game. Golden.
There are so many useless unnecessary assert(0)'s in the code. I saw one issue on github related to vehicles code and removing assert would prevent crash with no bad side effects.
I'm sure the deletion of the physics object in the case of the gun is to prevent a memory leak, albeit an extremely minor one.
4:09 regarding the hallway that deletes you, there is a similar phenomenon in HL1. In the map c2a5b (Surface Tension, right after the cliffside walk), if you climb on top of the smaller tank without destroying it beforehand you will get teleported to the previous area, half-stuck inside the concrete floor, and not even the "noclip" command can get you out of there. I wonder if climbing on top of the smaller tank deletes you just like in this case because if you use "impulse 101" in this state the game will type "Got a NaN origin on [weapon/ammo name]" in the console for each weapon/ammo unit, but you still get the weapons. Interestingly enough, shooting the Hivehand types the same console message but with "hornet" as the entity name.
P.S: as a Team Fortress 2 veteran, seeing you survive for so long in that situation was honestly jaw-dropping even for a jaded player like myself...
Hmm, I can't seem to replicate what you're saying, but I think what you describe is actually a result of a level transition happening without the player being "visible" to a certain entity related to level transitions. As a result, the player entity is not "saved" through the transition, which locks your view to some default position (likely 0,0,0).
Damn! The glitch with the tank has always bugged me, since no one knows what I mean or why it happens! Glad someone else has noticed it.
I need to press my interact key when on top of the Bradley for it to happen to me though.
On my first playthrough I thought it was just some not implemented system for taking control of the turret or something, but that seems unlikely, especially since we later just find a tank with an open hatch you can control.
When scout mains reach 10000 hours in the game, they gain the ability to become impervious to death just so long as they are within über stuffing distance of a medic with more than 70% über.
Left 4 Dead 2 has a similar bug on the Dark Carnival finale.
When the finale is triggered, it shuts a door behind you
and deletes any players and NPCs stuck behind it rather than using a kill plane.
Speedrunners use this to kick bots from the server forever by incapacitating them at the start then triggering the finale.
And on the (peer to peer network) Xbox 360 version, you can crash the entire server if the host gets deleted.
I'm pretty sure that the issue there is some iffy physics calculation resulting in the player's position being set to NaN.
In "floating point numbers" (the way computers usually handle numbers that can have a fraction) you have three main kinds of values: real values (+7.0, -11.5, +2678.027891), the infinities (+infinity and -infinity), and NaN (standing for "not a number"). Any invalid math operation (like 0.0 / 0.0 or infinity - infinity) will return NaN, and any math operation involving NaN will also return NaN. You can think of it as "poisoning" any expression it appears in, to signal that the whole thing is invalid.
So if your position ever gets set to NaN, there is almost no movement option (short of a straight-up teleport) that can move you away from that "position". When forcibly converting NaN to an integer or some other system that doesn't support weird float values, it will usually be treated as zero, so that's probably why your viewpoint appears to be 0,0,0 (the map origin).
I'm loving the more frequent uploads! definitely the most interesting HL2 channel around right now!
The fact that HL2, a game that will soon be two decades old, is its own entire genre on youtube, is funny. But I'm glad it is.
I like how - in the very moment of the crash - you have blackwhited the frame. it's a nice touch. the explanations are gold as you have attached the source code parts with the scenarios as well... great job and good video! very educational and entertaining in the same time
Okay am I crazy if I said that I would love to hear this guy break down crashes in a bunch of other video games. I just love how he gets so technical with it.
Ur weird
Furry detected
This video was super good. I really enjoy the obscure and technical side of half life 2 and other source games.
i would have died 30 times already if i was you in that tf2 clip...
The greatest Source anomaly of all is how the hell he managed to avoid those kritz rockets and kill the soldier- medic combo with a sun-on-a-stick
ok so what you can do to a crash your game, which is prob my favorite way. You can take a prop, rub it against the edge of a combine car tire to make it fly (yes it will just fly lol), and if you crouch jump into it, you will magically acquire its property, then if you just save and load, then load again, you will crash. Also doing stuff with props in the weird state after loading once will also crash at times.
Bill's Big Thrill is a powerful drug.
@@T3sl4 very
this channel makes me feel like I'm taking a college course on half life 2
1:42 Unity engines alternative is to just report the issue as a NullReferenceException and continue running as if nothing happened. it wont get any incorrect data or crash, it just "stops" the code where the error comes and doesnt run anything after it. if you had a custom console attached to the game instance and you built the game you would see a mile long list of NullReferenceException errors or just a single one, depending on where the error comes from and how often that section of code was called
This can be both good and bad. It's convenient for the player and seems like a good idea initially to let the game continue, but if the code stopping there results in other code malfunctioning as well, it can lead to even more instability.
As I was working on UI code in my Unity game, one of the null reference exceptions caused some initialization code to be skipped, which then resulted in an infinite loop somewhere else in the code, which then propagated to the C++ side of Unity and caused Windows to first (seemingly) run out of GDI handles, making the taskbar and other parts of the system flicker, then all windows' flags to reset, making otherwise hidden internal windows appear (much like how you can make them visible using tools like Process Hacker). It was very funny to realize this after looking at the logs.
On this note I want to mention that theres C++ native code and C# scripts. Any native exception will crash unity, but C# one, as you mentioned, wont.
I cannot believe you won that with a damn sun-on-a-stick lmao
I enjoy videos like these that show the code of these game crashes.
3:58 Halo also has triggers that delete the player, when they clip out of the map into certain spots, get too far away from the map, or part of the level spawns on top of their location. On the Halo 3 level The Covenant, if you jump into the path of the light bridge after fighting two Scarabs, and the bridge activates with you right in the way, you will despawn, the camera will lock up, the HUD will disappear, and a moment later you will respawn
Sun on the Stick confirmed greatest weapon of all time
This reminds me of how in GTA San Andreas (on the PC version) if you have something like a rocket launcher before doing the mission for Zero where you shoot down planes on the roof with the minigun, you'll lose that weapon at the end of the mission. It'll still be in your inventory, but it'll be missing an icon and won't fire. Trying to aim with it crashes the game. I'm guessing it was another null pointer situation?
Probably
Its likely, the minigun and rocket launcher occupy the same slot I think, so maybe the game tries to restore your weapon inventory after the mission is over, but it wasn't implemented properly.
3:14 this kind of optimization may not be for speed, but for memory usage instead. it may even be a memory _leak_ which could eventually lead the game to a crash. its possible it may be a memory leak because _maybe_ what happens is whenever the gun ends up as a phys object again, such as when the rebel drops it to pick up another gun, it creates a new phys object for it, and replaces all the pointers of the old one. if the old one was never deleted, then, well, it's leaked.
But, in that case, wouldn't you just be able to reuse the physobj instead of creating new one?
@@user-lj9dy2he4i potentially yes, but you have to remember this is the source spaghetti monster we're dealing with here
if reusing the same physobj was a possibility, why would they need to delete them at all? even if they wanted to stop using that particular physobj for that particular object, and just recycle that physobj instead of remaking a new one later, surely they still wouldnt even need to delete it then either?
@@Templarfreak you could be right though. However, I also figured it might be a measure to reduce overall memory used, as destroying physobj most likely deallocates it
@@user-lj9dy2he4i right, that's what i was suggesting in OP. i was also just pointing out a potential reason why it _has_ to be done for stability reasons and not just memory usage reasons, tho
@@Templarfreak I mean, if they were to reuse it, you don't have to recreate it. Why would that produce a leak?
I feel like you could become the Decino of Half Life games if you continue making analysis videos like this. This in-depth breakdown of what is causing the crashes is really interesting.
A guess at the helicopter/speed crash cause - designer wants to run a script "on-spawn" for the helicopter, but can't do it the same frame it spawns because initialization hasn't happened. So they delayed it "at least one frame" at 0.06s. If the player gets targeted by the uninitialized helicopter, it's game over.
My thought was that it was supposed to move to an initial waypoint somewhere around the trigger (via the input mentioned at 6:05), but if you move too fast, that waypoint gets unloaded. Since the helicopter cannot access that unloaded waypoint, it doesn't know where to go, and it crashes.
This seems like a very far-fetched explanation, though, and I don't think that's what's actually happening here. Seems more like something that would happen in Mario 64 than in Source.
I think if you go into that part of the Citadel where you get the physics gun but you already have a physics gun (via the command "physcannon_mega_enable 1") it will crash.
OMG BLUE WHAT A GMOD REFERENCE
that tf2 clip is the best showcase of skill i’ve ever seen
Please Please Please do more of these. Your dead-pan delivery and the subject matter itself work so well together. Plus there are so many videos about glitches in games that you rarely see videos just about crashing the game. It's fascinating to be reminded of the fragility of game code.
In portal 1, it is possible to fizzle yourself. All you have to do is spawn an airboat (ch_createairboat) and drive into a fizzler. And unlike the trigger that removes you at 4:00, the game actually does crash. I didn't check if it crashes on steam pipe, i know for sure it crashes on the 3420 build.
It does. I tried to do an Airboat% run and that was the major problem in my "runs".
What an oversight! How could they not think of the airboat problems in portal!
Next way is using my 20 years old computer, so nostalgic
These videos are literally my favorite types of videos. Monotone analysis of the game's innerworkings. For some reason I just can't get enough of them.
1:30 POV: You talked about Tianenmen Square in China.
This is surprisingly in-depth and well put together. Congrats
Super interesting, I love seeing this kind of stuff!
Almost 20 years old game and still alive, thats awesome. Gonna play again HL2 when i buy PC.
I love these types of videos because you get an insight into the code of the game and interesting oversights/bugs the developers had missed and why they actually happen.
Please do another video like this soon! For whatever reason this was really entertaining! I don’t understand code but I love listening to people explain it!
Thank you, Pinsplash for uploading this interesting video about interesting ways that the interesting game Half-Life 2 can interestingly crash.
This video has just made me realise that, in all my years of playing half Life, I've never experienced a bug or crash of any kind.
I refuse to believe modern developers and games studios are unable to replicate this
Right as the vortigaunt shocked the barrel, my power went out.
Great video! As a C++ devleoper, I can relate. Disappointed by the amount of unsafe coding in the source engine. I guess it was done for speed - remember, HL2 came out in 2004 (or 2003?), and it ran very well on old hardware.
Do you know how he managed to run HL2 through VSCode? I'd like to debug Civilization IV in the same manner so I can mod it. I have the source code, too.
@@nooneinparticular3370 Its visual studio not vscode
You’re like desinc but a billion times smarter.
good vid, grew up playing this engine im sure a lot of ppl have too; it's interesting to see this kinda stuff
Interesting
would love to see more stuff like this
damn, this is a pretty cool video man. I subbed from just 1 video which doesn't happen often lol. keep it up friend this was awesome
That TF2 clips was fucking nasty, WTH? How did you get away with that?
Also, really cool content, of course. I don't really understand how you got access to the source code (and especially comments) without getting the leaked build, but I love getting a look at the code and seeing why things work the way they do.
btw, I didn't think that the object being removed being the cause of the crash is surprising at all. I think the reason for the physics object being removed is probably to save RAM, unless I'm misunderstanding something about the nature of the physics object. But I do agree that it is unnecessary. The amount of RAM saved should be negligible, and shouldn't be able to result in a memory leak. Or maybe it's just kind-of muscle memory to delete an object when it should no longer be possible to access it.
I also want to know, where is the code from? If not from the leak?
Bravo, I require more! I MUST know these obscure yet interesting facts. The hidden dev comments are also extremely interesting and, IMO, worthy of their own video if there’s enough of them.
I want more of these videos tbh, after watching another youtubers videos on his analysis of different aspects of the og doom engine, I was searching for the same thing for the source engine as well and now I have it
You sounded like Decino channel explaining all the technical bugs/exploits/design flaws in the original Doom
I really like this
Amazing video I would love to see more crash video explanations
Very unique video. I have never seen one like this detail why a game crashed. Very good stuff.
I love the way you visualized the crash with a black and white screenshot
I remember finding a crash with the can cop where if you put the can in the trash then throw it at the cop it will just exit to desktop. Very interesting video though, nice to finally have somewhat of an idea as to why the helicopter crashes. I'm not exactly a speedrunner but I am still very annoyed by it.
This crash on d1_trainstation_02 map does indeed happen. The timing on this is very tight, though as metrocop has to be hit after the trigger in the trashcan is triggered by the held can, but before the cop says "Alright, you can go."
Would using the notarget command to stop the npc from shooting you help the debugger not throw you into bullet functions?
And today we see even more how valve games and the source engine are held together with duct tape and string
This was really interesting as always!! Do you have a programming background?
I've only done some serious programming lately. before starting this channel, i spent about 3 years basically rewriting source engine documentation which involved a lot of in-game testing and looking at code. before that i took two programming classes in high school and knew the bare basics of html css python and java.
That assert instacrash with todo fixme thing is so real and relatable it hurts
Mastermind.
Love you broski!
Getting smacked to death by the sun on a stick would cause me to disconnect out of shame.
Thanks for explaining and providing the exact code too
I realized that valve really are trying to hide the number three you got gold source, source, and then source two technically, it would be called source one from half-life one source two as half-life two then source three as half-life Alex. I really think they don’t know how to count to three.
i still love HL2 and more of your videos
Neato, thanks for the detailed explanations :D
Very interesting! I like the tf2 clips as well
Great video!!
Code: **tries to dereference a null pointer**
Game: And I took that personally.
03:53 chilly line after so much ARGs i saw
Interesting... What about the crash at citadel_03 when you grab your weapons back? I assume that also has some null stuff, but then I wonder why it sometimes doens't crash.
Wow... knowing this now, this might help me when bug testing my game.
Premium sun-on-a-stick gameplay here
I remember in gmod I was messing with func_physboxes, those entities have a specific flag called Break on Touch, which does exactly as it said, so if u have said physbox at hp 10 or 1000 - it will always break. But if u set its hp to 0 ( which even says that it wont break ) and attempt to break it - the game still operates, but is in a weird softlock state
Code archeology is always fun. Best thing is when you're tracing a particularly nasty bug for hours and hours, only to find a comment on a function that you think is causing it: "this doesn't work"
my man literally dismantled an entire kritz using the sun on a stick and he just shoved it into the end to get the time up?
That was a good TF2 clip. Thank you.
i dunno what magic you use, but i've learned a ton of things about game engines and games stuffs like entities just by watching your video, without even noticing i was learning stuffs :D
It's amazing that after almost 20 years, Half Life 2 has some things we still don't understand
new pinsplash video, today day is a good day
I would love to see more vids that explain code and its relation to what the player sees
My favorite kinda bug video
epic video subscribed
I love stuff like this, nice
I misread the title as “ways to crash in half life 2” like you can crash the airboat in different ways lol
I actually have a good theory for the Helicopter crash; since the event tells the Heli to move to a specific pathing node, it's possible that when the Helicopter's initialized, it's pointer to 'what node are we located at' is set to NULL by default, and the event's there to give it somewhere to go at the start of the fight (set on a delay so the helicopter has time to set up first).
Hence why if you get the heli to run the "saw the player approaching" code before that path variable's been initialized through the I/O event, when it tries to figure out where it should move to engage the player, the failsafe check passes since the helicopter doesn't have any node set, thusly setting off the false assert crash. I imagine a crude fix to not make it apparent to the player that it doesn't know what it's supposed to be doing would be to run a basic distance-check to find the nearest node to the heli's position, then assume 'that's where we're supposed to be' and return it while setting the variable to that same node...
These are some incredibly easy null pointer fixes. The second one for throw, just have a check for the phys object to only do what it does when "Phys object not null" have it take the object and throw. If "Phys Object null" then just cancel throw and revert to regular play like it would normally. The only reason a lot of these are not fixed is they were missed for long enough and effect the game very rarely so the discovery and then priority were later and lower.
Love half life 2.
I need to hear this man say "rise and shine, mr. freeman-rise and shine."
Came for the TF2 clip and it was worth the 8 minutes of waiting.
This was a good video but that TF2 clip at the end was nothing short of a miracle bahahahaha
Awesome video
The first one is similar to if you delete the actors from the opening scenes (alyx, barney, kleiner, however, lamar is probably the only actor ive deleted through console commands and the game went through the opening scenes no problem, just lamar wasnt there. I think this is because lamar's script events occur regardless, while barney, alyx, and kleiner need to walk over and press buttons n whatnot to keep the scene going)
Found this right before I was going to bed. 8 more minutes is fine
"The process is not entirely hygienic."
"I have been wearing this suit for 23 years straight."
You added unrelated footage to hit the 8 minute mark, but still didn't. Pretty wholesome, if you ask me
You are becoming the same thing to Half Life series that Decino is for Doom
I don't fully understand all the code shenanigans but its still incredibly interesting
And that second bug is almost certainly being handled by the engine. Happens in lots of source games such as when waiting for asynchronous task to complete. Just keeps playing the buffered audio
I mean, the Airboat 'crash' could be any number of things, knowing the Source engine's usual code hijinks. It getting stuck in a bullet-tracing function's pretty odd though, since the other suspects I might have for an infinite-loop error (kinematics code for keeping the feet on whatever the cop's standing on accidentally gets a NaN position, entity pathing having zero clue where to move from that position, etc.) aren't really included... considering that 'enginetrace' function call, one might presume that the cause is in that function, by the name it might be something that could get stuck infinitely iterating over the entity list; but it's likely to be in the raw engine source code, not the HL2 source, hence why tracing it would be difficult...