The spikes trick in Sonic 1 and the water drop hitboxes were the craziest facts for me. and about how much of a life I have, well, I'd just say I wish I have more time to make my own stuff like you with your research. 😅
I bet the developers _wish_ they had tools to look at the hit boxes like this. A load of these issues look like they exist because the devs had to look at them in a bunch of text boxes with numbers rather than visual images.
These videos have godly editing, this deserve the 100 thousand subscribers at the very least. They take long to arrive, but with this quality is well deserved the wait, keep it up!
I think the reason the hitbox of Robotnik's chemical blobs is off-center is so that they are positioned correctly when they first start falling. If you look closely, you'll notice that the position of the projectile is the same as the position of the box when it drops.
So how would one create a physics system like this? It's awesome you can visualize it, but I think it would be even more awesome if you could create a tutorial to recreate this movement/collision c: Yeah there's a Physics Guide but that is only in semi-code and doesn't apply to modern game engines in some cases, and the tutorials that are there on the internet never tackle slopes, only straight movement, and even then it's rarely correct to the Physics of Sonic. I have created movement on straight surfaces like Sonic just fine but slopes are just so difficult to handle with very little explanation as to the how.
The guide is designed to apply to any game engine (I know because I have been adding to it for years!) if there's anything about the guide that confuses you or you feel needs better explaining, please DM the Twitter account @SonicPhysics (me) and I can explain things or make changes. But when it comes to slopes, in particular sonic slopes, the main advice I give is make the collision yourself using your own system, don't rely on the built in collision functions or default systems in these modern IDEs, otherwise it's likely to be even harder to do the advanced stuff (and in worst cases, affect your physics in ways you can't control). It'll mean less/faster code, more control, and better results.
It would have to then check many many 1px squares rather than just 1 big one, saves a ton on processing. These days computers can do it easy, but it is still simpler to code, design, and process with simple boxes.
@@Foaklore Plus, when done right, the player's not actually going to notice if the hitbox doesn't line up 1:1 with the model. And sometimes, if something's hitbox perfectly matches an object's size, the player will say the game's cheap and that they're getting hit when they "clearly" avoided something, or that they should've picked something up but didn't. So, devs usually rig the game slightly in the player's favor so the player thinks the game is fair and not rigged against them.
for context, hitboxes are really simple as all they require is comparing the sums of the objects' coordinates and dimensions, i.e. you can tell if two objects are overlapping horizontally by checking a.x + a.width > b.x - b.width and a.x - a.width < b.x + b.width. or, in other words, by checking if a's rightmost edge is to the right of b's leftmost edge, while its leftmost edge is to the left of b's rightmost edge then you just a similar check for the other dimensions and bam, you can now tell if a and b are overlapping with only a handful of checks and instructions. checking for overlapping pixels has nothing so elegant, unfortunately
Making hitboxes being the same as the sprites would make the game coding much difficult than they need to be, and also putting too much pixelated hitboxes would cause it to lag a lot. That's why it's recommended to make collisions as close as possible without using too much hitboxes.
Ngl, collisions are EXTREMELY frustrating to work with when creating a Sonic/Sonic-Esc game! 🙄But this video is so eye opening, and here I thought Sonic's slope physics were perfect!
This was quite honestly very fascinating to see. I'm under the impression that you really studied this stuff. I tried studying python years ago and I made some progress but then unfortunately my medication for my ADHD had just gotten so expensive I couldn't afford to keep spending as much as I had to every month to get it so it was hard to focus and a class I should have completed years ago I am nowhere close to done. But the fact is I find this kind of stuff to be fascinating. Maybe I could find a way to set some time aside to really learn this stuff too. Growing up I've actually wanted to design video games but I just hadn't really had the confidence in ability to code or design them. The closest thing I can say I am done is make entire campaigns on the starcraft campaign editor and used the tools within that campaign Editor to make there be dialogue between characters and cause conditions to trigger actions to happen not just victory in the feet but various other actions that would allow you to progress on the starcraft mission. Well anyways, this was really awesome to watch so I'm the subscribing and curious about a whole lot more
this was actually really useful, right now im developing a sonic framework in GMS2 and i was struggling to understand some sections of the physics guide!
And me complaining that the little game I'm making while learning Python have messy hitboxes, but then you remind me of the evil robot crab of Metropolis.
An even easier strategy: When he first appears just jump at him 8 times before he gets to do his attack and go to the left/middle before you fall into the water.
I'm guessing the Big ring hitbox in Sonic 1 is long vertically while centered to make it appear that you are jumping through the ring, and not collecting it.
I like useing the term "Hurtbox" when dealing with boxes that hit you instead of hitting the foe to differenciate the term hitbox ive seen this consept in fighting games all time time its nice to finally see it in platformers especialy in Sonic games
Damn, sometimes the youtube algorithm doesn’t miss. I’ve fallen in love with your editing style and I’m pumped for the sonic 3 video! You’ve got a new sub pal
Bro, that's a lot of crazy stuff I didn't know about the hitboxes. I wonder if the hitbox oddities still are present in the mobile remake of the game (like the Metropolis' crab or Chemical Plant's boss).
commenting at 0:35 into the video. I've played these games from the day they were first released; I'm not a speed-runner, I don't actually have personal or intrinsic knowledge of the code and physics engine at a programming level, but my navigation of the games is almost entirely intuitive muscle-memory all these years later... I'm looking forward to see what you have to share with this, and I already know that I'm gonna be screwing with this collision overlay tonight when I'm done with household chores :D
Very good and informative video. I’ve played these games for almost two decades, and I never knew the reason why Sonic avoided damage from the chemicals but Tails didn’t.
For some Reason, Perhaps due to my Greater-than-Standard interest in Technology, Video Games, and Game Design, I easily find this one of my Favourite Videos on your Channel
Glad to see I wasn't the only one who found that jump through spikes bug as a kid. I very carefully jumped through the section of spikes to the left of the tvs on Green Hill Act 2 thinking there must be some secret, but nope.
This is really neat. the box hitbox is disappearing makes sense, particularly becasue bosses where the boss disappears and reappears and you can embed Sonic in the middle of their hitbox, and you don't hit the boss every frame when you do so.
@@LapperDev It is interesting that it happens for Sonic 1, a game that I don't recall having any "teleport" bosses, as well as not having Spin dash, as a way to maybe attack and pass through a boss hit box. Sonic 2 had Sliver Sonic, who I would basically beat by spin dashing through when he dashes without spinning. and Sonic 3 had the act 2 boss of Angel Island as a "teleporter", so it's not like they didn't have use for the concept in the sequels.
I have the feeling the blob hitbox is off center, is because it's actually a larger sprite then it looks. Like the blob is the upper/right corner of a 2x2 sprite block. The other blocks simply have no graphics in them. Or something...
About the Metropolis zone it is really annoyed by asteron ,the crab with a long hand and also the grasshoppers but then that one day I literally speedrunning without getting any damages
@@LapperDev well, I have seen this happening before and for sure that's not a good sign. But your content is quite good so I don't mind even if SS ends up getting cancelled 👍
I am willing to bet the reason the hitbox for the chemical plant boss is like that is so you get hit if you are jumping at robotnik as he is doing his attack animation, that offset hitbox comes out right at the corner of the container.
I thought that Sonic surviving that Chemical Plant Boss attack was because he deflected it with his spines... Like a hedgehog Also Tails doesn't have spines to protect himself so he cannot deflect the attack
some instances of that slope in emerald hill also exhibit the same no-slope-physics traits in their top half that you highlighted in the marble zone slope object, i've noticed. it's very silly rolling on them only to come to a dead stop a couple inches down.
Because of the way it works, the flagging of that EHZ tile means you will be able to walk on it as if it is a flat wall (angle = 90), hence the flying straight up when leaving) when you are already rotated, but ALSO as if it was a flat floor (angle = 0) when you are already right side up. I noticed its oddness way before I looked into Sonic games and I always did wonder why.
here's my theory about the Sonic 2 Chemical Plant boss: Sonic doesn't get hit because he's curling up into a ball, his quills are protecting him. Tails doesn't do that, he just crouches, so he's still vulnerable. Is this actually why they did this? Probably not, but I like to imagine it is.
Jumping between individual spikes like: ♪ Oh, I have all my fingers ♫ ♪ The knife goes chop chop chop ♫ ♪ If I miss the spaces in-between my fingers will come off ♫ ♪ And if I hit my fingers ♫ ♪ The blood will soon come out ♫ ♪ But all the same I play this game cause that's what it's all about ♫ ♪ Oh, chop chop chop chop chop chop ♫ ♪ I'm picking up the speed ♫ ♪ And if I hit my fingers then my hand will start to bleed ♫
WHY DOESNT THIS HAVE 1000 MORBILLION VIEWS UR SO TALENTED U DESERVE WAY MORE U CAN EDIT BETTER THAN MOST BIG CHANNELS U CAN MAKE GORGEUOUS PIXEL ART BETTER THAN LOTS OF PIXEL ART IN BIG GAMES UR AMAZING U CAN CODE TOO
I think I know why the chemical blob hitbox is like that. If you watch the way it's used in the attacks the egg mobile will frequently move toward the falling blob and the hitbox could have been moved so that it doesn't hit the egg mobile while it's falling. Essentially, the hitbox may have been moved there to prevent It from destroying the egg mobile when it's dropped and when it's falling.
I hate that I know most of these quirks and abuse them on a daily basis in ROM hacks. Speaking of, the script doesn't seem to work on ROM hacks at all, even after changing the header to the original games, despite the fact that for most of them the hitbox system stays the same, it's a shame cause this would've been a great script to use for debugging.
Yep, unfortunately to provide the information (the real information as it happens, rather than guessing based on specific object ram data) the script has to run functions during execution of specific lines of the game code that are present in the rom. All the EX_* values are positions in the code for the Sonic 1 REV01 in this case. Not saying it's very practical, but if you could manage to correctly reposition all the EX_ values in the script for the code in a hack build, it would then work for that too (only if it's still Sonic 1 and the stuff being read still works the same).
@@LapperDev Yeah at that point you may as well make a collision view system in the ROM hack instead cause things will inevitably shift around (not to mention completely break on new systems, such as the one in "I made you a Salad", where the collision sizes are in their own dedicated bytes instead of part of a look up table)
