How I re-created the rhythm game osu! from scratch in C++! 

so true willy

hello paralysis monster

Hehe, thanks!

i dont know if there was a reference to what you said in the video, but im pretty sure osu! stable is probably lighter than this edit : nvm got it

the funniest thing that just drawing a window with a button in it is usually the hardest part ;)

jjk brainrot in osu comments!!!

Heheh, thanks! I am still pretty "new" at this video creation thing and I constantly trying new techniques :D

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@@ohasanov keep it up!

> use the bottom screen just for controlling the cursor or tapping So the whole game? lol Following with a stylus that doesn't register when you touch down on the screen would not feel good. Not sure the official osu client even has that option on touch devices. That seems like smelly UX, but I haven't played on a touch osu client It seems like that would only work for a taiko or mania or catch, but not the classic osu...

Thanks! About those features... The first one is actually already implemented! Partly at least... There is the option to chose the top screen but I haven't added full touch controls yet, the menu kinda relies on "two hand input" right now, so yeah fixing that would be nice. The second one is a bit hard, since it would tank the fps... I don't really have much RAM left as far as I can understand. I maybe can enable that mode on new3ds consoles, but yeah, not too sure about that. The "not so great" looking textures is because the filtering mode somehow doesn't work, I am working on that hehe...

Yeah hahah, aspire maps are a great way to stress test the engine though! The fact that I can create the sliders in microseconds on my PC just makes me happy. The thing with osu!stable is because it precalculates all of the objects I think, since yeah the ram usage is a lot higher compared to lazer :)

@@ohasanov aspire slider distortions could easily be implemented without any precalculations, it's a simple x/y scaling/skewing based on the curve bounding box and coordinate system limits (32768).

@@McKay1901 I meant like the sliders on 'XNOR XNOR XNOR', there are some stuff there that currently needs precalc on my slider calculator... I am pre calculating each curve's length beforehand so that I don't calculate more points than needed in runtime. There are some bezier sliders for example consisting from hundreds of 1 length sub curves for example. Can't really guess each curve's length sadly :') At least I haven't done that till now... Also, I have never heard about skew/distortions... maybe I need to research that a bit more

Thank you very much!

Thanks!

Haven't seen them sadly, though my curve algorithm works just fine right now :)

Thanks hahah! Not really to be honest, it is never too late!

Yeah, it is called osus-revented! Although, after somr messing around with the 3DS, I see now that the memory management is not, will rewrite some stuff in the following weeks. About the optimizations, some algorithms (like getting the points themselves) I borrowed, but the way of using those algorithms to create evenly spaced points I found out myself :)

Heh, thanks! I need to make the code more readable first though. It is really visible how the code was written for my eyes only lol, its not that unreadable but its not great either. :)

@@ohasanov lmao I get it. I do the same thing too with my codes xD

Yeah so there should be a folder named "beatmaps", I just noticed that it isn't there on github, sorry. You can create the "beatmaps" folder in the same place as the "resources" folder

Yeah! Look for the keywords: devkitPro, libctru, citro2d and citro3d! These are the basic stuff you want to research for 3DS homebrew

I am still working on the 3ds port. The audio side of the whole thing kinda sucks on the 3ds... Will figure it all out though! When I have a stable enough build, I will post an update!

@@ohasanov okay 👍,take your time

Ah, I liked watching his videos, and his style of fun videos is what I want to achieve, sure. But gotta say, I was trying to create stuff like this even before seeing Dani's videos, I just didn't have the time to finish and publish those projects...

@@ohasanov ah its okay! i wasn't saying you're trying to copy his style. It just reminds me of him whenever i see a gamedev video since his videos are so enjoyable.

@@prismatic-bl8qf Hahah. Yeah they really are...

Honestly, in my opinion he is just too inexperienced in programming, bezier curves are super simple, even quadratic, etc. ones. Looking at the code on github, his style is somewhat messy and not very readable at times.

@spaghettiking653 Bezier curves just by themselves aren't a challenge, yes. It's just the way osu needs those result points. The bezier algorithms are pricey (computation), and they generally do not give equally distanced points. First time I implemented the curves, the creation of a slider took about 10ms and tanked the framerate in half while rendering it. Currently, on my rig I can generate all the sliders in a 10 minute map in under 20ms. Less stutter, more performance, less memory usage, that was the hard part (at least for me)

​​@@raremc1620Sure, as a self taught solo developer, the way I write my code isn't optimal, I am not saying that I am the best at this, or that the way I write my code is the best way. No, it surely isn't, seeing how the mistakes I made 2 years ago are biting me in the back now. I just tried to show my determination, how I try to learn by creating new things, and completing all the projects. It's mostly fun anyway :) Also maybe I need to note this but the bezier curves in osu! are Nth order, mappers generally don't adhere to a limit so it becomes a bit weird when you have to calculate 2000 points for a 40th order bezier.

@@ohasanov Honestly, you are doing great, nothing wrong with being imperfect, everyone has stuff to learn even if you are experienced :) Just mentioning a potential reason of why it could've been harder to get done.

@@ohasanov Oh dear, okay, that makes sense. I just now think I realized why you need equally-spaced points: because the slider ticks occur at regular time intervals, right?

Hope my explanation will be at least understandable, here we go. So first I create a circle texture with a gradient. Pure red in the center, less Alpha the more distance you have from the center. Then, when creating the sliders I create a texture that will fit all of the points of the slider. Draw the red circle I first created on the slider texture each render point. While doing that, use a blend mode so that the Alpha channels aren't added and this way, you basically have a curve thats "Glowing", (Pure red curve created by the red center of the circle texture, the glow created by the gradient). Then, while rendering the slider texture, I just check the Alpha channel and recolor the fragment based on the distance from the center. It is definitely not the best way of doing this, but this method works on OpenGL1.1 too! Sadly the 3DS doesn't support fragment shaders so I just use a blend mode (or a blend function) that only draws the color with the lower color values (First draw a white circle, then the black inner one. While rendering the second white circle, the blend mode makes it so that the white circle doesn't override the black circle and stuff)

​@@ohasanov I kind of get the idea, I've tried drawing the texture but I can't figure out how to not add the alpha channels, I've tried using different blend modes but none of them worked. Anyway I've build your application and I saw that you put your own game directory in "globals.hpp" ("C:/Users/renot/AppData/Local/osu!/Songs"). I think there must be a way to configure that using the %LOCALAPPDATA% environment variable

@@RugiSerl Yeah, I forgot to change it back to the default hahah... I will push a big fix in the following weeks, apparently the code is leaking a loooot of memory (Some of it thanks to raylib too...)

Eh to be honest it is. Code made for one single purpose...

Yeah! Was a great helper while I was trying to figure out slider lengths and stuff :)

Thanks, I am in no position to really say that a route is the best way though... For me, I think that creating new projects always helps, since different games need different things... Other than that, geeksforgeeks and stackoverflow! They are your friends!

@@ohasanov Thank u for your recommendations. Furthermore, may I also ask did you take any particular course for c++ before? I kinda tend to find online courses much memorable rather than sticking with the book solely. Any suggestion surely can be beneficial. Thanks in advance, sincerely.

@@_.-.-_.-.--.-_.- Hmm, I just learned C++ from random RU-vid Videos, no particular course or anything. Like I said, I liked finding my own way by asking my own questions to solve my own problems in my own projects :) I feel like courses just limit you, by teaching things set in stone. So yeah, sorry can't really recommend anything...

In some maps, it does actually use less ram!

Yes, however it has the ability to run at 268MHz just like the original. The two extra cores you can't really use anyway. You need to enable the 804MHz mode in the homebrew app for that speed. I currently do not do that, and it still runs at a decent speed. Additionally, the new2ds does have more ram, but I do not use that as well, you can configure that while building a .cia file.

Well yeah, it is another osu! client. The focus here is pure performance more than anything else though.

Yeah so apparently, it is not just slightly faster. The new 3ds can get a steady 60fps on debug builds, the old 3ds gets a lot of frame drops on even -O2 builds (this optimization flag changes a lot in my project). Thats what a cpu running 3 times faster does apparently

@@ohasanov doesn’t it also have more memory?

@@unyu-cyberstorm64 Yeah, but realistically, if you want your game to run on an old3ds, you really can't use the extra ram on the new models. More ram isn't always faster. But it does allow for bigger files to be loaded to memory, which speeds some things up especially when the 3ds has a really slow filesystem.

@@ohasanov ah yes, and a better GPU on the new models too and better 3D effect, right?

@@unyu-cyberstorm64 Uhm, afaik the gpu is the same, Pica 200 @133MHz in both consoles. The 3D is better cause they implemented eye tracking, probably made more possible with the addition of 2 more cpu cores (4 vs 2). Most games dont really use more than a single core though, the extra 2 cores are mostly reserved. (You can take advantage of them in homebrew though)

I mean, yeah technically, but with the same logic, using any kind of API would also be "not creating something from zero". I mean sure but heh, the meaning is not that. (Also technically speaking I rewrote raylib once or twice anyway so heh)

@@ohasanov I think we are on the same page. Keep working hard and you will get better. Optimised programming is a great way to become a better programmer and you are on a good track when it comes to the learning process. I personally wish I had the tools and knowledge available to me now since I started. Which is why I’m so excited for the future. Can’t wait to see what the next great step is gonna be in terms of an individual’s programming prowess. I’m referring to the next Terry Davis / Michael Abrash, John Carmack, Chris Sawyer, Alan Turing etc

Technically speaking, implementing it wouldn't be that hard as far as I can see, but I am no mania player and honestly know very little about how it works. I will definitely try to add the other game modes too though (taiko most probably, catch, idk...)

Thanks! About the lazer thing. Even lazer can't render most of the weirder sliders properly. On my hardware, on some maps osu lazer just dies for some reason. That was one part. The second being that I can't really read the C# code of lazer... That is 100% my problem though hahah!

He did also mention in the video that he wanted to implement everything cleanly (without taking/looking from other codebases). Copying lazer’s handling would contradict those value :p Very commendable work, makes sense why you decided on the principles you choosed since the primary objective is to make a performant version of osu, not to replicate in yet another language. (ps: Looking forward to this project, please make a pinned comment with the public repository if you ever do decide to crate one. Would like to try and port this to mobile :D )

​@@conturnplayscounturn6911Ah the repo is on my github (link in desc). Its called osus-revented (another word play. Vent. Reinvent) I dont recommend touching the repo now though, apparently I am leaking a lot of memory, and some stuff only work on my pc. I need to fix those. Once I do that, I will also be finished with the 3DS port, at which point I will post another video!

Mike wazowski

He is using stuff from C++ such as classes 3:28 you can see that there is a slider class

I thought by using C++ I can be a lot easier on myself by not having to manage the memory that much, but after some recent developments, it seems like I need to rewrite the memory management myself, vectors crash randomly on the 3DS :')

Sorry, I just am used to using Windows, and WSL is actually great for C++ dev environment I feel like...

I mean, yeah? If you know it thats no problem?

I mean, technically does now, its just that I didn't know much about the API (GPU and Sound) on the 3DS. I currently do have an unstable build that has audio but I need to rewrite the memory management, random crashes are not fun...

@@ohasanov that's honestly extremely impressive. I do recommend watching out for RAM consumption because on your vid it appears that it's using 110mb which is still a lot despite being technically below the limit imo

​@@himalayoyeah so 70mb of that is just Windows being Windows. I managed to actually make it play a map fully, max memory consumption was about 14MB or so (excluding textures and sound files), although the memory management is leaking some stuff, I definitely need to rewrite that...