Links in the api docs are nice. I noticed that there were several places
where structs / functions and other things were referenced in the docs,
but weren't linked. I added the links where possible / logical.
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Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
# Objective
Adds a new resource to control a global volume.
Fixes#7690
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## Solution
Added a new resource to control global volume, this is then multiplied
with an audio sources volume to get the output volume, individual audio
sources can opt out of this my enabling the `absolute_volume` field in
`PlaybackSettings`.
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## Changelog
### Added
- `GlobalVolume` a resource to control global volume (in prelude).
- `global_volume` field to `AudioPlugin` or setting the initial value of
`GlobalVolume`.
- `Volume` enum that can be `Relative` or `Absolute`.
- `VolumeLevel` struct for defining a volume level.
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Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- Fixes#6361
- Fixes#6362
- Fixes#6364
## Solution
- Added an example for creating a custom `Decodable` type
- Clarified the documentation on `Decodable`
- Added an `AddAudioSource` trait and implemented it for `App`
Co-authored-by: dis-da-moe <84386186+dis-da-moe@users.noreply.github.com>
