/** Move the person vertically by 'distance' pixels. */
public void moveVertical(int distance) {
erase();
yPosition += distance;
draw();
}
/** Make this person invisible. If it was already invisible, do nothing. */
public void makeInvisible() {
erase();
isVisible = false;
}
/** Move the person horizontally by 'distance' pixels. */
public void moveHorizontal(int distance) {
erase();
xPosition += distance;
draw();
}
/** Change the size to the new size (in pixels). Size must be >= 0. */
public void changeSize(int newHeight, int newWidth) {
erase();
height = newHeight;
width = newWidth;
draw();
}
