Realtime plugin application examples

[atsushieno]

Current aaphostsample is a static filter application example and not demonstrating realtime plugin application.

JUCE AudioPluginHost port is realtime, but it's only reacting on users key inputs (and audio input support is broken at JUCE level). It does not prove that AAP is useful for audio playback.

tracktion_engine is a candidate music playback engine, and we have augene project, but it fails to build at GitHub Actions stage, and there is no known .tracktioneditsong file that is valid and ready to play on Android, due to mismatches in state binary formats.

helio_workstation port can list up AAP plugins, but its plugin connection UI fails to show AAP output ports and therefore it is impossible to connect to the device audio outputs. It seems to generate some audio outputs with AAP plugins, but totally glitchy and not even sure if any plugin outcome is actually there. It's just some noisy oscillator output.

Solution ideas:

• extend current PluginPreview and its UI to support dynamic audio processing, accepting parameter changes.
• get augene to somehow working?
• get helio to somehow working?
• create a simpler MIDI sequencer that maps to AAP instruments?

[atsushieno]

AudioPluginMidiDeviceService opened up various opportunity to use instrument plugins as virtual MIDI devices. For example my kmmk can use any MIDI output device to play notes. aap-ayumi worked if we use MIDI 2.0 mode there.

[atsushieno]

I got aap-juce-helio working, which is another realtime plugin application example.

[atsushieno]

Now that we can use aap-juce-simple-host to play audio sample while applying effect plugin, as well as dynamically changing the parameter values, we can mark this task as completed.