Subsongs from module music played through libopenmpt

Expected behavior of the wanted feature

libopenmpt has an ability to view, get and separately play subsongs. You can implement subsong switching on the same buttons that are used for switching between audio files if multiple were selected to be played by MPV.
This, however, wouldn't work if multiple audio files were selected to be played, so read the "Alternative behavior of the wanted feature" for the solution

Alternative behavior of the wanted feature

If multiple audio files were selected to be played, then we can add another bar above which lets you switch between subsongs instead. Or you can use chapters/markers instead (If i recall correctly, i saw that MPV has an ability to display them), however, i'm not sure if you can loop between them...

Log File

No response

Sample Files

One of the modules that has subsongs is this one at The Mod Archive: Beyond the Network. No need to download it, just use the "Play with Online Player" feature and it will show subsongs without playing it.

FFmpeg resources

FFmpeg's libopenmpt.c (line 47)

FFmpeg Formats PDF: libopenmpt

Start with FFmpeg's libopenmpt.c and the OpenMPTContext::subsong reference, then trace how mpv handles audio-file selection and chapters or markers. The feature needs an agreed interaction model before implementation. Done means subsongs can be viewed and selected reliably for a module, including when multiple audio files are queued.