code: function draw (ctx, score) {
    console.log(score)
    drawStripes(box, ctx)
    forEachTime(function (time, note) {
      var midi = toMidi(note.pitch)
      console.log(time, note, midi)
      ctx.fillRect(box.x(time), box.y(midi), box.nw(note.duration), box.nh())
    }, null, score)
  }
docs: Draw a piano roll