Ability to set a Global Volume

crates/bevy_audio/src/audio.rs

@@ -128,6 +128,8 @@ pub struct PlaybackSettings {
     pub repeat: bool,
     /// Volume to play at.
     pub volume: f32,
+    /// Ignore global volume
+    pub absolue_volume: bool,
     /// Speed to play at.
     pub speed: f32,
 }
@@ -143,13 +145,15 @@ impl PlaybackSettings {
     pub const ONCE: PlaybackSettings = PlaybackSettings {
         repeat: false,
         volume: 1.0,
+        absolue_volume: false,
         speed: 1.0,
     };
 
     /// Will play the associate audio source in a loop.
     pub const LOOP: PlaybackSettings = PlaybackSettings {
         repeat: true,
         volume: 1.0,
+        absolue_volume: false,
         speed: 1.0,
     };
 
@@ -164,6 +168,12 @@ impl PlaybackSettings {
         self.speed = speed;
         self
     }
+
+    /// Helper to set if the volume sould ignore the global volume.
+    pub const fn with_absolute_volume(mut self, absolue_volume: bool) -> Self {
+        self.absolue_volume = absolue_volume;
+        self
+    }
 }
 
 #[derive(Clone)]
@@ -188,3 +198,23 @@ where
             .finish()
     }
 }
+
+/// Use this [`Resource`] to control the global volume of all non-absolute audio.
+#[derive(Resource)]
+pub struct GlobalVolume {
+    /// The global volume of all audio.
+    pub volume: f32,
+}
+
+impl Default for GlobalVolume {
+    fn default() -> Self {
+        Self { volume: 1.0 }
+    }
+}
+
+impl GlobalVolume {
+    /// Create a new [`GlobalVolume`] with the given volume.
+    pub const fn new(volume: f32) -> Self {
+        Self { volume }
+    }
+}

crates/bevy_audio/src/audio_output.rs

@@ -1,4 +1,4 @@
-use crate::{Audio, AudioSource, Decodable};
+use crate::{Audio, AudioSource, Decodable, GlobalVolume};
 use bevy_asset::{Asset, Assets};
 use bevy_ecs::system::{Res, ResMut, Resource};
 use bevy_reflect::TypeUuid;
@@ -70,6 +70,7 @@ where
         audio_sources: &Assets<Source>,
         audio: &mut Audio<Source>,
         sinks: &mut Assets<AudioSink>,
+        global_volume: &GlobalVolume,
     ) {
         let mut queue = audio.queue.write();
         let len = queue.len();
@@ -79,7 +80,7 @@ where
             if let Some(audio_source) = audio_sources.get(&config.source_handle) {
                 if let Some(sink) = self.play_source(audio_source, config.settings.repeat) {
                     sink.set_speed(config.settings.speed);
-                    sink.set_volume(config.settings.volume);
+                    sink.set_volume(config.settings.volume * global_volume.volume);
 
                     // don't keep the strong handle. there is no way to return it to the user here as it is async
                     let _ = sinks.set(config.sink_handle, AudioSink { sink: Some(sink) });
@@ -97,11 +98,12 @@ where
 pub fn play_queued_audio_system<Source: Asset + Decodable>(
     audio_output: Res<AudioOutput<Source>>,
     audio_sources: Option<Res<Assets<Source>>>,
+    global_volume: Res<GlobalVolume>,
     mut audio: ResMut<Audio<Source>>,
     mut sinks: ResMut<Assets<AudioSink>>,
 ) {
     if let Some(audio_sources) = audio_sources {
-        audio_output.try_play_queued(&*audio_sources, &mut *audio, &mut sinks);
+        audio_output.try_play_queued(&*audio_sources, &mut *audio, &mut sinks, &global_volume);
     };
 }
 

crates/bevy_audio/src/lib.rs

@@ -29,7 +29,7 @@ mod audio_source;
 #[allow(missing_docs)]
 pub mod prelude {
     #[doc(hidden)]
-    pub use crate::{Audio, AudioOutput, AudioSource, Decodable, PlaybackSettings};
+    pub use crate::{Audio, AudioOutput, AudioSource, Decodable, GlobalVolume, PlaybackSettings};
 }
 
 pub use audio::*;
@@ -56,6 +56,7 @@ impl Plugin for AudioPlugin {
             .add_asset::<AudioSource>()
             .add_asset::<AudioSink>()
             .init_resource::<Audio<AudioSource>>()
+            .init_resource::<GlobalVolume>()
             .add_system(play_queued_audio_system::<AudioSource>.in_base_set(CoreSet::PostUpdate));
 
         #[cfg(any(feature = "mp3", feature = "flac", feature = "wav", feature = "vorbis"))]