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5916a0b477
This reworks the auto-quit feature by introducing a new AudioBuffer class which keeps track of which channels are currently silent as audio flows through the effects chain. When track channels going into an effect's input are not marked as quiet, it is assumed a signal is present and the plugin needs to wake up if it is asleep due to auto-quit. After a plugin processes a buffer, the silence status is updated. When the auto-quit setting is disabled (that is, when effects are always kept running), effects are always assumed to have input noise (a non-quiet signal present at the plugin inputs), which should result in the same behavior as before. Benefits: - The auto-quit system now closely follows how it is supposed to function by only waking plugins which have non-zero input rather than waking all plugins at once whenever an instrument plays a note or a sample track plays. This granularity better fits multi-channel plugins and pin connector routing where not all plugin inputs are connected to the same track channels. This means a sleeping plugin whose inputs are connected to channels 3/4 would not need to wake up if a signal is only present on channels 1/2. - Silencing channels that are already known to be silent is a no-op - Calculating the absolute peak sample value for a channel already known to be silent is a no-op - The silence flags also could be useful for other purposes, such as adding visual indicators to represent how audio signals flow in and out of each plugin - With a little more work, auto-quit could be enabled/disabled for plugins on an individual basis - With a little more work, auto-quit could be implemented for instrument plugins - AudioBuffer can be used with SharedMemory - AudioBuffer could be used in plugins for their buffers This new system works so long as the silence flags for each channel remain valid at each point along the effect chain. Modifying the buffers without an accompanying update of the silence flags could violate assumptions. Through unit tests, the correct functioning of AudioBuffer itself can be validated, but its usage in AudioBusHandle, Mixer, and a few other places where track channels are handled will need to be done with care. --------- Co-authored-by: Sotonye Atemie <sakertooth@gmail.com>
