[FEATURE] Dual video source (Home/Lock separation)

[LaAutista]

Specs:
Pixel 8 running lineage OS (latest and on android 16). Rooted. All permissions given including battery. Unchecked manage app when not in use.

Selecting any of the three options always results in both home and lock screen using 1 .mp4 file instead of 2 separately. I am unable to have different .mp4 files for home and lock. It'll change the other to the same file regardless of which I choose first.

Also, sometimes the video playback just stops alltogether and becomes still. Regardless of looped option being chosen.

Lastly, sometimes the video is completely misaligned. Seems to be reproducible when constantly opening multiple windows and going through multiple apps. Undead Wallpaper is usually closed as I wish to just let it run in the background.

[maocide]

Hi @LaAutista, thanks for the report.

1. Separate Videos for Home & Lock Screen (Feature Request)

This is currently intended behavior due to the app's architecture, not a bug.

• How it works: The app stores a single "Current Video" preference. When the Wallpaper Engine starts (whether for Home or Lock), it reads this single source.
• The technical hurdle: Android's WallpaperService does not provide a reliable, native way for the Engine instance to know "I am currently running on the Lock Screen" during initialization. Implementing this requires complex logic to detect the context and a custom UI to specify a second video slot, which is a significant architectural change.
• I will mark this as a Feature Request for a future version, but it is not currently supported.

2. Misalignment & Playback Stopping

I am actually also running Android 16 (Pixel 10 Pro), and I am unable to reproduce the misalignment or the stopping issues. The app runs stable for days without shifting. Still thanks for pointing the problem out, if it will happen to me I will try to check logs and see if it's due to the OS aggressively killing the service for resources.

Since you are on LineageOS, this suggests the issue might be specific to how that ROM handles:

1. Window Resizing: The "misalignment" usually happens if the OS sends a resize event (e.g., hiding/showing navigation bars) but doesn't trigger the standard onSurfaceChanged callback correctly for the wallpaper service.
2. Memory Management: If the video stops, the OS is likely killing the MediaCodec decoder aggressively to save resources, which is common in custom ROMs even with battery optimizations off.

Because I cannot reproduce this on the official Android 16 Beta, I suspect this is a compatibility conflict with LineageOS's specific implementation of the Window Manager. I will keep an eye out for similar reports in case it's a wider issue. Also if it will occur on my Android 16, now, being aware of it, I will check the logs for information and look for a solution.

[LaAutista]

This might be useful to you.

https://github.com/cyunrei/Video-Live-Wallpaper

I have no issues using this older application that does the same thing your app does with less features. It does not have the bugs your app does at least for my install, as the wallpaper runs 24/7 non stop and no misalignment issues. Perhaps looking at their source code might give some useful insight?

[maocide]

Thanks for sharing the link!

I am actually familiar with that project. It’s a solid implementation, but it runs on a completely different architecture than UndeadWallpaper.

The Technical Difference:

• That App: Uses the legacy Android MediaPlayer API directly. It relies on the OS to handle the video rendering and scaling. This is "safer" for compatibility because it lets the system decide how to stretch the video, but it lacks precise control over scaling (Fit/Fill/Stretch) and often struggles with seamless looping or transitions.
• UndeadWallpaper: Uses a custom OpenGL Rendering Engine (with ExoPlayer). This allows for the features you see (Matrix scaling, positioning, precise fit/crop modes, battery efficiency) as well as avoiding stuttering that MediaPlayer has often.

Why it works on your setup:
Because the legacy app just hands the video to the OS, if LineageOS sends a weird "resize" event (the misalignment issue), the standard system player just ignores it or stretches the content blindly.
My engine calculates the exact pixels based on the screen coordinates reported by the OS. If the Custom ROM reports those coordinates incorrectly during a window transition, my engine tries to respect that data, resulting in the misalignment you see.

Unfortunately, looking at their source code doesn't apply here because we are speaking two different languages (Standard MediaPlayer vs. OpenGL Matrices). I cannot port their logic without removing the advanced scaling and rendering features that UndeadWallpaper is built around.

I appreciate the reference, though! It confirms that the issue lies in how the OpenGL surface is receiving coordinate updates on that specific ROM configuration.