feat: add mini performance overlay and GPU composition toggle for Android TV

[PacificSilent]

Force GPU Composition for Android TV + Mini Performance Overlay

Summary

This PR adds two features to improve the Android TV experience:

1. Force GPU Composition: Option to force GPU composition and fix stuttering/frame drop issues
2. Mini Performance Overlay: Ultra-compact performance metrics display mode

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Force GPU Composition

Problem it solves

On Android TV, some devices experience frame synchronization issues that cause:

• Stuttering during streaming
• Frame drops
• Inconsistent video playback

Solution

Adds an invisible TextView that forces Android to use GPU composition instead of hardware overlays, improving frame synchronization.

Implementation:

• Invisible TextView (1sp) in activity_game.xml
• Controlled by user preference
• Completely transparent, doesn't affect gameplay

When to enable:

• ✅ If experiencing stuttering or frame drops on Android TV
• ✅ If video doesn't play smoothly
• ❌ If streaming already works well

Modified files

• app/src/main/res/layout/activity_game.xml - Invisible TextView
• app/src/main/java/com/limelight/Game.java - Visibility control
• app/src/main/java/com/limelight/preferences/PreferenceConfiguration.java - Config
• app/src/main/res/xml/preferences.xml - UI settings
• app/src/main/res/values/strings.xml - Strings

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Mini Performance Overlay

Features

• Ultra-compact overlay (8sp) with essential metrics
• Format: BW: 109M/s PL: 0% Net: 7ms | Dec: 109ms XX.XX FPS
• Mutual exclusion with "Lite" mode (only one can be active)

Displayed metrics

• BW: Bandwidth
• PL: Packet Loss
• Net: Network latency
• Dec: Decode time
• FPS: Frames per second

Modified files

• app/src/main/res/layout/activity_game.xml - Overlay TextView
• app/src/main/java/com/limelight/Game.java - Metrics update
• app/src/main/java/com/limelight/binding/video/MediaCodecDecoderRenderer.java - FPS tracking
• app/src/main/java/com/limelight/preferences/StreamSettings.java - Mutual exclusion
• app/src/main/res/xml/preferences.xml - UI settings
• app/src/main/res/values/strings.xml - Strings

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Technical Changes

MediaCodecDecoderRenderer.java

• FPS tracking with updates every second
• Performance metrics for mini overlay

Game.java

• GPU composition TextView visibility management
• Real-time mini overlay updates

StreamSettings.java

• Mutual exclusion logic between Lite and Mini overlays

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Testing

Force GPU Composition:

• Test on Android TV with/without option enabled
• Verify stuttering improvement
• Confirm no performance impact

Mini Overlay:

• Verify correct metrics updates
• Confirm mutual exclusion with Lite mode
• Validate readability

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Compatibility

✅ Android TV (main beneficiary)
✅ Standard Android devices
✅ Backward compatible

[ClassicOldSong]

Thank you for the contribution, but this might not be needed when a bug in frame timing is fixed.

I'll leave this PR open for now in case it doesn't fix the problem.

[farnsworth3010]

I am still seeing unplayable stutters on mi TV Stick 4k gen 2 on the latest release and the latest beta. Toggling the overlay makes it butter smooth

[farnsworth3010]

Tried building your branch, now it works very well (2k 60fps with no stutters). Thank you! This little fix should definitely be merged.