public void touch(ArduinoSensor whichSensor) {
   if (interfacePiece.isPad) {
     interfacePiece.touch(((ArduinoPad) arduinoPiece).locationOnPad(whichSensor));
   } else if (interfacePiece.isSlider) {
     interfacePiece.touch(((ArduinoSlider) arduinoPiece).whichInSlider(whichSensor));
   } else {
     interfacePiece.touch();
   }
   repainter.repaint();
 }
 public void release(ArduinoSensor whichSensor) {
   interfacePiece.release();
   repainter.repaint();
 }