Music Player

The Music Player provides audio playback with playlist management, shuffle, repeat, and volume control. Music persists across window closes because playback lives in the USoundSubsystem.

Core Features

• Playlist Scanning: Automatically discovers .mp3, .wav, .ogg, and .flac files in the VFS.
• Transport Controls: Play, pause, skip forward/backward, and seek.
• Shuffle & Repeat: Toggle shuffle mode and repeat (loop) mode.
• Volume Control: Adjustable music volume via the USoundSubsystem.
• Persistent Playback: Music continues playing even after the Music Player window is closed.
• Now Playing Display: Shows current track name and playback progress.

Technical Details

• Controller Class: UMusicPlayerApp (Inherits from UAppBase)
• Widget Class: UMusicPlayerWidget (Hybrid — UMG BindWidgetOptional + embedded SMusicPlayer Slate)
• Window Specs:
  • Initial Size: 300x500
  • Resizable: true
  • Maximizable: true
• Category: "Media"

Key Controller Methods

• ScanPlaylist() — Discovers audio tracks from the VFS.
• PlayTrack(Index) / PlayNext() / PlayPrevious()
• ToggleShuffle() / ToggleRepeat()
• GetCurrentTrackIndex() / GetPlaylist()

Delegates

• OnPlaylistChanged() (dynamic/BP)
• OnCurrentTrackChanged(int32 Index, FOSSIMMusicTrack Track) (BP event)

Sound Integration

The Music Player is a user-facing controller for the USoundSubsystem, which handles the actual audio playback:

• USoundSubsystem::PlayTrack(Track) — Loads audio via StaticLoadObject and polls for 0.25s completion.
• USoundSubsystem::GetPlaybackProgress() — Returns normalized playback position (0.0–1.0).
• USoundSubsystem::SeekToNormalized(Position) — Scrubs to a specific position.

Audio Track Data

FOSSIMMusicTrack: TrackName, VFSPath, AssetPath, DurationSeconds.

Default volumes: MasterVolume=0.75, MusicVolume=0.75, bIsLooping=false.