Any time warping will cause wrong chart offset

Gennadiyev commented 3 months ago

Describe the bug When using Practice mode, despite the chart playback speed and song pitch being scaled by a user-defined factor, apparently there is a major desync between song and chart.

To Reproduce Steps to reproduce the behavior:

Start any chart.
Enter practice mode mid-game.
Set any start pos & end pos & playback rate < 1.
Playback by pressing the top-left button.

Expected behavior Synced playback of both song and chart.

Screenshots

https://github.com/user-attachments/assets/a67409ec-9666-4e40-914e-bef79d0761fd

Device specs

Device: iQOO Neo 8
OS: Android 14
Version 2.0.0 Beta 2 Patch 5

I strongly appreciate the efforts that the developers put into making this mode possible. It's an incredible feature that few rhythm games (and emulators for them) are able to implement and make it a breeze for the users to use. Great job! 👍🏻

2394425147 commented 3 months ago

Will look into this as soon as time allows, thanks!

Gennadiyev commented 3 months ago

Thank you so much for the timely reply. FYI, #122 might be related to this. Basically Time Warp is flawed:

For the chart playback, it seems to be an offset issue, not a BPM desync. The chart always lags (need verification), regardless of the time warp mod's speed param being set to >1x or <1x.
The video playback always syncs with audio!

Will keep testing to help identify this issue.

2394425147 / astrodx

Any time warping will cause wrong chart offset #127