Module player 

Player: the rules of playing a frame’s audio, shared by every backend (game ADR-0026, ADR-0063), behind the small Backend trait a backend writes: the sound and voice requests and the music commands App hands the sound device (AudioFrame).

The player keeps the cues’ volumes, picks a variant, plays at most two tracks in a crossfade, their gains moving opposite ways (ADR-0054), and plays the voice clips (game ADR-0046). PlayerDevice is the whole of a backend’s Audio over it.

A sound started with a handle (SoundRequest::Start) is one playback the player keeps by its id, so that one copy stops alone and its volume follows the requests and the player’s sound volume.

Holding a sound (ADR-0056). A sound paused under a menu (SoundRequest::PauseSounds), and everything sounding while the system suspends the game (Player::suspend: the sounds started with a handle, the voice and the music), is held with Backend::pause. A backend that can’t pause says Unsupported, and the player mutes instead: the sound runs on silently, so a track’s clock runs too, and comes back at the volume it would have had. A paused track’s clock holds.

It also knows when each track really started (Player::music_playing, game ADR-0037): a track asked for only sounds once its file has loaded, and screens that keep time with the music need the real moment.

Structs

Player

The audio player: owns the decoded sounds and the music tracks.

PlayerDevice

The Audio of a backend that writes only Backend: its backend and, once the game has loaded, the Player over it. Before that there is nothing to play.

Unsupported

What a Backend’s provided method says on a backend without the feature: the player then carries on with the feature’s fallback.

Constants

RATE_ONE

A playback rate of 1.0, as Backend::set_rate takes it: 16.16 fixed point, so a sound plays as recorded.

Traits

Backend

What playing audio needs from the platform: all a backend writes for the sound of a game (ADR-0063).