This is my research on how to play videos in openfl haxeflixel (webm only supported)

BEFORE SETUP apologies to benlonghair the war has ended ok so
(btw this is for Friday Night Funkin)
ALSO IF YOU ARE IN LINUX OR MAC AND THE COMMAND lime DOES NOT WORK BUT YOU INSTALLED IT THEN DO haxelib run lime INSTEAD!

1. Download the Friday Night Funkin source code in https://github.com/ninjamuffin99/Funkin and follow EVERYTHING (including the git part which is very important) (make sure its the new file system otherwise you need to put extra code which i have the solution for lol)
2. Install actuate by doing haxelib install actuate
3. Install the extension-webm fork by doing haxelib git extension-webm https://github.com/GrowtopiaFli/extension-webm

If You Are On Mac Please Download XCode In The App Store Before Proceeding
If You Are On Linux Please Run This Command With The Packages Or Similar

sudo apt-get install libgl1-mesa-dev libglu1-mesa-dev g++ g++-multilib gcc-multilib libasound2-dev libx11-dev libxext-dev libxi-dev libxrandr-dev libxinerama-dev
    
4. It won't work lol so type the command lime rebuild extension-webm [windows/mac/linux/android] (depends on your device)
   
   EXTRA STEP FOR ANDROID!
   
   Run These Commands:
   
   lime config HXCPP_ARM64 true
lime config HXCPP_x86 true
   
   STILL PRETTY UNSTABLE THO!
   
   ALSO IF YOU ARE IN ANDROID FOLLOW THE ANDROID STUDIO INSTRUCTIONS IN https://github.com/luckydog7/Funkin-android
    
5. Download the zip of this repository and copy paste the files inside the source folder to your fnf source code's source folder
6. Edit the Main.hx file in the fnf source code
   Then add after the code

addChild(new FlxGame(gameWidth, gameHeight, initialState, zoom, updateframerate, drawframerate, skipSplash, startFullscreen));

And before code

#if !mobile
addChild(new FPS(10, 3, 0xFFFFFF));
#end

The code

var ourSource:String = "assets/videos/DO NOT DELETE OR GAME WILL CRASH/dontDelete.webm";

#if web
var str1:String = "HTML CRAP";
var vHandler = new VideoHandler();
vHandler.init1();
vHandler.video.name = str1;
addChild(vHandler.video);
vHandler.init2();
GlobalVideo.setVid(vHandler);
vHandler.source(ourSource);
#elseif desktop
var str1:String = "WEBM SHIT"; 
var webmHandle = new WebmHandler();
webmHandle.source(ourSource);
webmHandle.makePlayer();
webmHandle.webm.name = str1;
addChild(webmHandle.webm);
GlobalVideo.setWebm(webmHandle);
#end

So it would look something like

addChild(new FlxGame(gameWidth, gameHeight, initialState, zoom, updateframerate, drawframerate, skipSplash, startFullscreen));
		
var ourSource:String = "assets/videos/DO NOT DELETE OR GAME WILL CRASH/dontDelete.webm";
		
#if web
var str1:String = "HTML CRAP";
var vHandler = new VideoHandler();
vHandler.init1();
vHandler.video.name = str1;
addChild(vHandler.video);
vHandler.init2();
GlobalVideo.setVid(vHandler);
vHandler.source(ourSource);
#elseif desktop
var str1:String = "WEBM SHIT"; 
var webmHandle = new WebmHandler();
webmHandle.source(ourSource);
webmHandle.makePlayer();
webmHandle.webm.name = str1;
addChild(webmHandle.webm);
GlobalVideo.setWebm(webmHandle);
#end

#if !mobile
addChild(new FPS(10, 3, 0xFFFFFF));
#end

1. Edit Project.xml in the fnf source code
2. Find the section with <haxelib name="etc" />
3. Add these two extra lines

<haxelib name="actuate" />
<haxelib name="extension-webm" if="desktop" />

4. FOLLOW THIS 4TH STEP ONLY IF YOUR USING THE OLD FILE SYSTEM In the section with <assets path="bla">
   Add these two lines

<assets path="assets/videos" include="*.mp3" if="web"/>
<assets path="assets/videos" include="*.ogg" unless="web"/>

5. If your in the new file system
   Create a new folder named videos inside assets/preload
   If your in the old file system
   Create a new folder named videos inside assets
6. Paste the DO NOT DELETE OR GAME WILL CRASH folder inside the videos folder (either assets/preload/videos or assets/videos SOURCE CODE SPECIFIC) if you don't you know what happens, game crashes.

For all you windows users out there You need to do an extra step You must know how to use cmd or Command Prompt or Terminal for mac or something idk i don't have a mac
(sorry but this is only for 64 bit architectures)

1. Download ffmpeg https://github.com/BtbN/FFmpeg-Builds/releases (please download the gpl shared version there is also download for mac please download ffprobe: https://evermeet.cx/ffmpeg)
2. Extract the zip file to your choice
3. Go inside the bin folder inside the extracted zip file
4. Open Command Prompt or Terminal
5. Change directory inside the bin folder
6. More on this later

As you know, this only supports webm video files not mp4 or any other file type
The reasoning of this is because of the different types of codecs not embedded inside openfl
Let me give an explanation
Video Files require a codec
a codec is an encoder or a decoder for video files
You CANNOT compress video files to a smaller size in modern times because they are already COMPRESSED and that is why we have codecs so you can't push the limit
OpenFL has no codec embedded into it that's why someone who made openfl-webm coded the webm codec from scratch using c++ for haxe/openfl
But if you will ask Why does it work for html?
It's because when it comes to html the BROWSER has the codec
If you were to do it Natively Native means an application that uses the system's commands instead of depending on other software like browsers which is for html5, there are no codecs built into it.
Now if you were to ask Why is it named extension-webm if it was openfl-webm then? It's because openfl-webm is ancient and broken so someone made extension-webm to fix it: https://github.com/HaxeExtension/extension-webm
Now if you were to ask Then why did i install https://github.com/GrowtopiaFli/extension-webm instead of https://github.com/HaxeExtension/extension-webm then? It's because i added some extra code in WebmPlayer.hx to fix memory leaks.
Now if you were to ask What are memory leaks? well a memory leak is a thing wherein the memory is stuffed and not freed, in basic terms, your RAM processes more data.
Why you ask? it's because the video isn't being replaced but keep being added each time.
How did i fix this issue you asked? i added extra code to WebmPlayer.hx which allows you to change the SOURCE VIDEO of the webm player anytime.

Now how will we setup the video on desktop?
Well in webm player there is NO audio support because it's broken lol so now we are in trouble but do not worry because ffmpeg is here to save us.
My solution is to Audio Sync a way of Synchronizing the audio version of the video to the video You must have an ogg file either just the video's audio or just empty audio that lasts as long as the video's time (i made a solution so if you don't have audio on your video then just don't make an ogg file).
So back to that ffmpeg change directory folder is a ffprobe command template i have

./ffprobe -v error -count_frames -select_streams v:0 -show_entries stream=nb_read_frames -of default=nokey=1:noprint_wrappers=1 "yourvideo.mp4"

Ok so my recommendation is to Convert your video to webm then convert that webm to an mp4 because sometimes there are frame losses to webm files which fails the Audio Sync.
This command logs the number of frames your video has and now you may ask.
If i have to convert webm to an mp4 because of frame loss for ffprobe why the hell can't i just input the webm file? Well it's because ffprobe cannot detect the frame numbers in your webm files so you have to use a different format.
Now you may ask What am i suppose to do with the frame numbers? You have to make your video name first.
Let me give a video name sample of video.
Now inside the videos folder in either assets/preload/videos or assets/videos (SOURCE CODE SPECIFIC) if the video name is video then make a file called video.txt and put the frame numbers there as easy as that.
2. put your webm file in so it will be video.webm
3. put the ogg converted file in so it will be video.ogg
IMPORTANT NOTE THAT THERE ARE DIFFERENT CODECS FOR WEBM FILES THE SPECIFIC ONE IS VP8 WHILE VP9 AND OTHERS AREN'T SUPPORTED

You can edit VideoState.hx all you want but the usage of the VideoState class is pretty simple.
The return must be a new class but i made a separate VideoState.hx file inside the function folder in this repository to change the callback to a function.

FlxG.switchState(new VideoState('assets/videos/yoursourcevideo.webm', new YourClass(), your frameskip limit which you can leave blank or put a frameskip limit you can fill this parameter voluntarily and it must be an integer not a decimal, [true/false] (if it is true, the music playing will automatically be paused, this is good for midway videos while playing or idk for pausing the game and showing the video cutscene)));

YourClass is your callback class which is called once the video ends so you put your own logic idk
Frameskip limit should be an integer not a decimal
enter true or false for music auto pause and resume
WARNING WARNING! function is very unstable and won't work do not copy the contents of the function folder please and also you make your own class with code or something idk i won't be your coding teacher ask kadedev or something idk

Thank you for taking your time to read the entire repository ReadMe file.
This is the end of the document i hope you understood everything i wrote for you to play videos in Friday Night Funkin.
Support the kickstarter here: https://www.kickstarter.com/projects/funkin/friday-night-funkin-the-full-ass-game