public void movePegsHorizontally(Peg a, Peg b, Peg c) {
        a.centerX = centerX - width/2 + Peg.width/2 + horMargin;
        b.centerX = centerX - width/2 + Peg.width + Peg.width/2 + horMargin*2;
        c.centerX = centerX - width/2 + Peg.width + Peg.width + Peg.width/2 + horMargin*3;
    }