YoYo Loader Externalising .OGGs Instructions: For reducing the size of game.droid and game memory usage

gistfile1.md

YoYo Loader Externalising .OGGs Instructions:

• For reducing the size of the game.droid file and game memory usage.
• Note: Doing this won't guarantee your game will start working in YoYo Loader.

You Will Need:

• UndertaleModTool: https://github.com/krzys-h/UndertaleModTool
• Archive extractor. Example: 7zip: https://www.7-zip.org/
• ffmpeg package/executable https://ffmpeg.org/download.html
• Game files of your GMS game.

Setup:

• Extract UndertaleModTool to a directory on your PC.
• Extract ffmpeg to a directory on your PC.
• Move your data.win/game.droid and any audiogroup.dat files to a new directory.
• Make a backup of the directory containing the data.win/game.droid and audiogroup.dat files.

Step 1: Externalise embedded audio files

• Open the game.droid file of your GMS game in UndertaleModTool.
• Navigate to the "Scripts>Run Community Scripts" tab and find "ExternalizeAllOGGs.csx" and click to run it.
• Click yes to both pop ups. (first confirms you made a backup of your files, second splits the exported files by audiogroup).
• A folder will be created in the same directory called "Exported_Sounds" containing all embedded audio files.
• Save your game.droid file. It should be smaller in size.

Step 2: Converting exported .WAV files to .OGG format

• Within the "Exported_Sounds" folder you will find one or more subfolders containing .WAVs and .OGGs audio files.
• Locate the "ffmpeg.exe" in your ffmpeg directory and copy and paste it into the "Exported_Sounds" folder.
• Open a Powershell Console window.
• In the script below, edit the $filepath varaible with the path to your "Exported_Sounds" folder.
• Now run the script in Powershell.

 $filepath = 'C:\[YourFilepathToTheSubFolder]\Exported_Sounds'

Get-ChildItem $filepath -recurse -include *.wav | 
Foreach-Object {
    $nameNoExt = $_.BaseName
    Set-Location -Path $_.Directory
    $ArgumentList = "-i `"$nameNoExt.wav`" `"$nameNoExt.ogg`""
    Start-Process -FilePath $filepath\ffmpeg.exe -ArgumentList $ArgumentList -Wait -NoNewWindow

    Remove-Item -Path $_
}

• This script will use "ffmpeg.exe" to convert all .WAVs to .OGGs in all the subfolder within "Exported_Sounds".
• The script will also delete all .WAV files.
• Once the conversion is complete, delete the "ffmpeg.exe".

Step 3: Correcting audiogroup references in game.droid

• If you only have one subfolder in "Exported_Sounds" (audiogroup_default), skip to Step 4.
• If you have 2 or more subfolders, you will need to correct the audiogroup references within game.droid.
• Warning: This can be a time consuming manual process, depending on how many audiogroups there are.
• Open the game.droid file of your GMS game in UndertaleModTool.
• Navigate to the "Audio groups" drop down in the project browser (left) and expand it.
• Navigate to the "Sounds" drop down in the project browser and expand it.
• Double click one of the "Sounds" entries to open it and observe the "Audio group" field.
• Drag one of the entries under the "Audio groups" drop down and drop it onto the Sound file "Audio group" field.
• Observe how the "Audio group” reference is repalced.
• Using this "Drag and Drop" method and cross-checking against the named subfolders of your externalised .OGGs.
• You must ensure all externalised sound files have the correct audiogroup reference.
• Once completed, save your game.droid file.

Step 4: Repacking the assets

• You can now drop the game.droid, audiogroup.dat files and "Exported_Sounds" folder back into your APK.
• Ensure to add the .OGG files to the APK as "store". This is explained in Step 4 of the Asset Swap tutorial.