colorPadsList function

Uint8List colorPadsList(int padRow, int padColumn, List<PadColor> colors)

turn on and set pads with the colours in the list, starting at padRow, padColumn

Implementation

Uint8List colorPadsList(int padRow, int padColumn, List<PadColor> colors) {
  final colorsBytesLength = colors.length * 4;
  final lengthHighByte = colorsBytesLength >> 7;
  final lengthLowByte = colorsBytesLength & 0x7F;
  final sysexHeader = Uint8List.fromList([
    0xF0, // System Exclusive
    0x47, // Akai Manufacturer ID
    0x7F, // The All-Call address
    0x43, // “Fire” product
    0x65, // Write LED cmd
    lengthHighByte, // mesg length - high byte
    lengthLowByte, // mesg length - low byte
  ]);
  final sysexFooter = Uint8List.fromList([
    0xF7, // End of Exclusive
  ]);

  final startPadIndex = (padRow * 16 + padColumn);

  int i = startPadIndex;
  final dataList = colors.map((color) => Uint8List.fromList([
        i++,
        color.r,
        color.g,
        color.b,
      ]));

  final ledData = Uint8List.fromList(dataList.expand((x) => x).toList());

  final b = BytesBuilder();
  b.add(sysexHeader);
  b.add(ledData);
  b.add(sysexFooter);

  final midiData = b.toBytes();
  return Uint8List.fromList(midiData);
}