This extensive PR rewrites the internal mixing logic of the driver to use symphonia for parsing and decoding audio data, and rubato to resample audio. Existing logic to decode DCA and Opus formats/data have been reworked as plugins for symphonia. The main benefit is that we no longer need to keep yt-dlp and ffmpeg processes alive, saving a lot of memory and CPU: all decoding can be done in Rust! In exchange, we now need to do a lot of the HTTP handling and resumption ourselves, but this is still a huge net positive.
`Input`s have been completely reworked such that all default (non-cached) sources are lazy by default, and are no longer covered by a special-case `Restartable`. These now span a gamut from a `Compose` (lazy), to a live source, to a fully `Parsed` source. As mixing is still sync, this includes adapters for `AsyncRead`/`AsyncSeek`, and HTTP streams.
`Track`s have been reworked so that they only contain initialisation state for each track. `TrackHandles` are only created once a `Track`/`Input` has been handed over to the driver, replacing `create_player` and related functions. `TrackHandle::action` now acts on a `View` of (im)mutable state, and can request seeks/readying via `Action`.
Per-track event handling has also been improved -- we can now determine and propagate the reason behind individual track errors due to the new backend. Some `TrackHandle` commands (seek etc.) benefit from this, and now use internal callbacks to signal completion.
Due to associated PRs on felixmcfelix/songbird from avid testers, this includes general clippy tweaks, API additions, and other repo-wide cleanup. Thanks go out to the below co-authors.
Co-authored-by: Gnome! <45660393+GnomedDev@users.noreply.github.com>
Co-authored-by: Alakh <36898190+alakhpc@users.noreply.github.com>
Adds support to the library for tokio 0.2 backward-compatibility. This should hopefully benefit, and prevent lavalink-rs from being blocked on this feature.
These can be reached using, e.g., `gateway-tokio-02`, `driver-tokio-02`, `serenity-rustls-tokio-02`, and `serenity-native-tokio-02` features.
Naturally, this requires some jiggering about with features and the underlying CI, which has been taken care of. Twilight can't be handled in this way, as their last tokio 0.2 version uses the deprecated Discord Gateway v6.
* Driver Benchmarks
Benchmarks driver use cases for single packet send,
multiple packet send, float vs opus, and the cost of
head-of-queue track removal.
Mix costs for large packet counts are also included.
This is a prelude to the optimisations discussed in
#21.
* Typo in benchmark
* Place Opus packet directly into packet buffer
Cleans up some other logic surrounding this, too. Gets a 16.9% perf improvement on opus packet passthrough (sub 5us here).
* Better track removal
In theory this should be faster, but it aint. Keeping in case
reducing struct sizes down the line magically makes this
faster.
* Reduce size of Input, TrackHandle
Metadata is now boxed away. Similarly, TrackHandles are neatly Arc'd to reduce their size to pointer length (and mitigate the impact of copies if we add in more fields).
