io.pde.pi

int rotaryA = 0;
int rotaryB = 0;
int newState = 0;
int lastState = 0;

int pinA = 27;
int pinB = 17;


// watch pins

void updatePinA(int pin) {
  GPIO.noInterrupts();
  rotaryA = GPIO.digitalRead(pinA); 
  updatePosition();
  GPIO.interrupts();
}

void updatePinB(int pin) {
  GPIO.noInterrupts();
  rotaryB = GPIO.digitalRead(pinB); 
  updatePosition();
  GPIO.interrupts();
}

// update position based on pins

void updatePosition() {
  int xorVal = rotaryA ^ rotaryB;
  
  // Get the new rotary encoder state
  int newState = (rotaryA * 4) + (rotaryB * 2) + (xorVal * 1);
  
  // Get the delta (difference) between the previous state and the new state
  int delta = (newState - lastState) % 4;
  // Store the state for next time around
  lastState = newState;

  //delta:
  // 0 = no change
  // 1 = one step clockwise
  // 2 = two steps in either direction
  // 3 = one step counter clockwise
  switch(delta) {
    case 1:
      playheadManager.modifyPositionBy(-1);
      //console.log(count);
      break;
    case 3:
      playheadManager.modifyPositionBy(1);
      //console.log(count);
      break;
    case 2:
      //console.log('-');
      break;
  }
}