Script using mididings to improve the functionality of behringer x-touch with Ardour DAW

mididings_xtouch_proxy.py

"""
Very simple mididings script to enhance the functionality of a behringer
x-touch mixing control surface when used with a DAW via the mackie control
protocol (MCP). Written for use with Ardour and an x-touch running firmware
v1.21. Might work with other DAWs and firmware versions, might steal your
wallet and drink your booze. Idea stolen from a similar effort done with MaxMSP
/ PureData for use with Cubase:

https://www.pgaudio.com.br/site/improve-mackie-controller-xtouch-integration-daw

Meant to be run as a proxy on the MCP input channel. MIDI out from the x-touch
should be routed into mididings input, and mididings output connected to the
DAW's MCP input.
"""

import time

from mididings import *
from mididings.engine import output_event
from mididings.event import NoteOnEvent, NoteOffEvent

config(
    backend='jack',
)

def note_events(ev, note):
    """
    Generate a note on/off pair for the provided event's port and channel.
    """
    noteOn = NoteOnEvent(ev.port, ev.channel, note, 127)
    noteOff = NoteOffEvent(ev.port, ev.channel, note, 64)
    return [noteOn, noteOff]

def delay(ev, note, ms=40):
    """
    Pause for specified number of milliseconds before emitting a note on/off
    pair.
    """
    time.sleep(ms/1000)
    noteOn, noteOff = note_events(ev, note)
    output_event(noteOn)
    output_event(noteOff)
    return

run(
    Filter(NOTEON) % KeySplit({
        # send: The `send` button allows setting output levels for the selected
        # track's sends, using the pan knobs by default. this auto-clicks the
        # `flip` button to switch to the fader controls. I thought I'd have to
        # awkwardly and wrongly track the `flip` button state to decide whether
        # it needed to be hit, but it seems like hitting `send` toggles the
        # `flip` button off so this always works as desired.
        41: +Call(delay, 50),

        # fader bank left: Auto-clicks `select` button on the leftmost track
        # after `fader bank left` is hit. This causes the DAW UI to show the
        # same tracks that are showing on the x-touch.
        46: +Call(delay, 24),

        # fader bank right: Same as above but the other direction. This gets
        # janky at the end of the track list; unless the track count is a
        # multiple of 8 the rightmost track on the x-touch won't correspond to
        # a track in the session, so the `select` button will have no
        # effect. It'd be great to know this and instead select the last
        # existing track, but no way to tell at the moment.
        47: +Call(delay, 31),

        # channel left / channel right: These next two are the same as the
        # previous two but for single channel left and right instead of fader
        # bank left and right.
        48: +Call(delay, 24),
        49: +Call(delay, 31),
        None: Pass(),
        })
    )