half working claviature

packages/codemirror/widget.mjs

@@ -126,3 +126,8 @@ registerWidget('_scope', (id, options = {}, pat) => {
   const ctx = getCanvasWidget(id, options).getContext('2d');
   return pat.tag(id).scope({ ...options, ctx, id });
 });
+
+registerWidget('_claviature', (id, options = {}, pat) => {
+  const ctx = getCanvasWidget(id, options).getContext('2d');
+  return pat.tag(id).claviature({ ...options, ctx, id });
+});

packages/draw/claviature.mjs

@@ -0,0 +1,115 @@
+import { Pattern, noteToMidi } from '@strudel/core';
+
+const blackPattern = [0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0];
+
+export const tokenizeNote = (note) => {
+  if (typeof note !== 'string') {
+    return [];
+  }
+  const [pc, acc = '', oct] = note.match(/^([a-gA-G])([#bs]*)([0-9])?$/)?.slice(1) || [];
+  if (!pc) {
+    return [];
+  }
+  return [pc, acc, oct ? Number(oct) : undefined];
+};
+const accs = { '#': 1, b: -1, s: 1 };
+const toMidi = (note) => {
+  if (typeof note === 'number') {
+    return note;
+  }
+  const [pc, acc, oct] = tokenizeNote(note);
+  if (!pc) {
+    throw new Error('not a note: "' + note + '"');
+  }
+  const chroma = { c: 0, d: 2, e: 4, f: 5, g: 7, a: 9, b: 11 }[pc.toLowerCase()];
+  const offset = acc?.split('').reduce((o, char) => o + accs[char], 0) || 0;
+  return (Number(oct) + 1) * 12 + chroma + offset;
+};
+
+const getMidiKeys = (range, offset) => {
+  const white /* : number[] */ = [];
+  const black /* : number[] */ = [];
+  const to = noteToMidi(range[1]);
+  for (let i = offset; i <= to; i++) {
+    //
+    (blackPattern[i % 12] ? black : white).push(i);
+  }
+  return [white, black];
+};
+
+const whiteWidth = (midi, topWidth) => (midi % 12 > 4 ? 7 / 4 : 5 / 3) * topWidth;
+
+const whiteX = (midi, offset, topWidth) =>
+  Array.from({ length: midi - offset }, (_, i) => i + offset).reduce(
+    (sum, m) => (!blackPattern[m % 12] ? sum + whiteWidth(m, topWidth) : sum),
+    0,
+  ); // TODO: calculate mathematically
+
+/* const blackX = (index, offset, topWidth) => {
+  const cDiff = 12 - (offset % 12);
+  console.log('cDiff', cDiff);
+  const cOffset = whiteX(cDiff + offset);
+  const blackOffset = cOffset + cDiff * topWidth;
+  return (index - offset) * topWidth + blackOffset;
+}; */
+
+const parseNote = (note) => (typeof note === 'number' ? note : toMidi(note));
+
+export function claviature(haps, options) {
+  const {
+    ctx = getDrawContext(),
+    range = ['A1', 'C6'],
+    scaleX = 1,
+    scaleY = 1,
+    palette = [getTheme().foreground, getTheme().background],
+    strokeWidth = 0,
+    stroke = getTheme().foreground,
+    upperWidth = 14,
+    upperHeight = 100,
+    lowerHeight = 45,
+  } = options || {};
+  const offset = parseNote(range[0]);
+  const colorize = haps.map((hap) => ({ keys: [hap.value.note], color: hap.value.color || getTheme().selection }));
+  /* const to = parseNote(range[1]);
+  const totalKeys = to - offset + 1; */
+  /* const width = totalKeys * topWidth + topWidth + strokeWidth * 2;
+    const height = whiteHeight; */
+
+  const topWidth = upperWidth * scaleX;
+  const [white, black] = getMidiKeys(range, offset);
+
+  const whiteHeight = (upperHeight + lowerHeight) * scaleY;
+  const blackHeight = upperHeight * scaleY;
+
+  const cDiff = 12 - (offset % 12);
+  const cOffset = whiteX(cDiff + offset);
+  const blackOffset = cOffset - cDiff * topWidth;
+
+  const blackX = (index) => (index - offset) * topWidth + blackOffset;
+
+  const colorizedMidi = colorize.map((c) => ({
+    ...c,
+    keys: c.keys.map((key) => parseNote(key)),
+  }));
+  const getColor = (midi) => colorizedMidi.find(({ keys }) => keys.includes(midi))?.color;
+  ctx.clearRect(0, 0, ctx.canvas.width * 2, ctx.canvas.height * 2);
+  ctx.strokeStyle = stroke;
+  ctx.strokeWidth = strokeWidth;
+  white.forEach((midi) => {
+    ctx.fillStyle = getColor(midi) ?? palette[1];
+    const x = whiteX(midi, offset, topWidth);
+    const width = whiteWidth(midi, topWidth);
+    ctx.fillRect(x, 0, width, whiteHeight);
+    ctx.strokeRect(x, 0, width, whiteHeight);
+  });
+  black.forEach((midi) => {
+    ctx.fillStyle = getColor(midi) ?? palette[0];
+    const x = blackX(midi, offset, topWidth);
+    //ctx.strokeRect(x, 0, topWidth, blackHeight);
+    ctx.fillRect(x, 0, topWidth, blackHeight);
+  });
+}
+
+Pattern.prototype.claviature = function (options) {
+  return this.draw((haps) => claviature(haps, options), { id: options.id });
+};

packages/draw/index.mjs

@@ -3,3 +3,4 @@ export * from './color.mjs';
 export * from './draw.mjs';
 export * from './pianoroll.mjs';
 export * from './spiral.mjs';
+export * from './claviature.mjs';