/** Move the snake forward every update. */
public void advance() {
if (currentState == State.IDLE) {
currentState = State.MOVING;
}
SnakePart head = snakeParts.get(0);
int snakeLength = snakeParts.size() - 1;
for (int i = snakeLength; i > 0; i--) {
SnakePart previousPart = snakeParts.get(i - 1);
SnakePart snakePart = snakeParts.get(i);
// set the part's new position to the previous parts position.
snakePart.setX(previousPart.getX());
snakePart.setY(previousPart.getY());
}
switch (movementDirection) {
case UP:
head.setY(head.getY() - 1);
break;
case DOWN:
head.setY(head.getY() + 1);
break;
case LEFT:
head.setX(head.getX() - 1);
break;
case RIGHT:
head.setX(head.getX() + 1);
break;
}
}
