Merge pull request #699 from tidalcycles/midi-in

Midi in

packages/core/controls.mjs

@@ -1066,7 +1066,6 @@ const generic_params = [
    */
   ['waveloss'],
   // TODO: midi effects?
-  ['midicmd'],
   ['dur'],
   // ['modwheel'],
   ['expression'],

packages/core/pattern.mjs

@@ -2343,3 +2343,9 @@ export const fit = register('fit', (pat) =>
 export const { loopAtCps, loopatcps } = register(['loopAtCps', 'loopatcps'], function (factor, cps, pat) {
   return _loopAt(factor, pat, cps);
 });
+
+/** exposes a custom value at query time. basically allows mutating state without evaluation */
+export const ref = (accessor) =>
+  pure(1)
+    .withValue(() => reify(accessor()))
+    .innerJoin();

packages/midi/midi.mjs

@@ -5,7 +5,7 @@ This program is free software: you can redistribute it and/or modify it under th
 */
 
 import * as _WebMidi from 'webmidi';
-import { Pattern, isPattern, logger } from '@strudel.cycles/core';
+import { Pattern, isPattern, logger, ref } from '@strudel.cycles/core';
 import { noteToMidi } from '@strudel.cycles/core';
 import { Note } from 'webmidi';
 // if you use WebMidi from outside of this package, make sure to import that instance:
@@ -15,8 +15,8 @@ function supportsMidi() {
   return typeof navigator.requestMIDIAccess === 'function';
 }
 
-function getMidiDeviceNamesString(outputs) {
-  return outputs.map((o) => `'${o.name}'`).join(' | ');
+function getMidiDeviceNamesString(devices) {
+  return devices.map((o) => `'${o.name}'`).join(' | ');
 }
 
 export function enableWebMidi(options = {}) {
@@ -52,30 +52,28 @@ export function enableWebMidi(options = {}) {
     });
   });
 }
-// const outputByName = (name: string) => WebMidi.getOutputByName(name);
-const outputByName = (name) => WebMidi.getOutputByName(name);
 
-// output?: string | number, outputs: typeof WebMidi.outputs
-function getDevice(output, outputs) {
-  if (!outputs.length) {
+function getDevice(indexOrName, devices) {
+  if (!devices.length) {
     throw new Error(`🔌 No MIDI devices found. Connect a device or enable IAC Driver.`);
   }
-  if (typeof output === 'number') {
-    return outputs[output];
+  if (typeof indexOrName === 'number') {
+    return devices[indexOrName];
   }
-  if (typeof output === 'string') {
-    return outputByName(output);
+  const byName = (name) => devices.find((output) => output.name.includes(name));
+  if (typeof indexOrName === 'string') {
+    return byName(indexOrName);
   }
   // attempt to default to first IAC device if none is specified
-  const IACOutput = outputs.find((output) => output.name.includes('IAC'));
-  const device = IACOutput ?? outputs[0];
+  const IACOutput = byName('IAC');
+  const device = IACOutput ?? devices[0];
   if (!device) {
     throw new Error(
-      `🔌 MIDI device '${output ? output : ''}' not found. Use one of ${getMidiDeviceNamesString(WebMidi.outputs)}`,
+      `🔌 MIDI device '${device ? device : ''}' not found. Use one of ${getMidiDeviceNamesString(devices)}`,
     );
   }
 
-  return IACOutput ?? outputs[0];
+  return IACOutput ?? devices[0];
 }
 
 // send start/stop messages to outputs when repl starts/stops
@@ -164,3 +162,31 @@ Pattern.prototype.midi = function (output) {
     }
   });
 };
+
+let listeners = {};
+const refs = {};
+
+export async function midin(input) {
+  const initial = await enableWebMidi(); // only returns on first init
+  const device = getDevice(input, WebMidi.inputs);
+
+  if (initial) {
+    const otherInputs = WebMidi.inputs.filter((o) => o.name !== device.name);
+    logger(
+      `Midi enabled! Using "${device.name}". ${
+        otherInputs?.length ? `Also available: ${getMidiDeviceNamesString(otherInputs)}` : ''
+      }`,
+    );
+    refs[input] = {};
+  }
+  const cc = (cc) => ref(() => refs[input][cc] || 0);
+
+  listeners[input] && device.removeListener('midimessage', listeners[input]);
+  listeners[input] = (e) => {
+    const cc = e.dataBytes[0];
+    const v = e.dataBytes[1];
+    refs[input] && (refs[input][cc] = v / 127);
+  };
+  device.addListener('midimessage', listeners[input]);
+  return cc;
+}