private static final void drawSquareFootprint(Graphics graphics, int x,
            int y, int thickness) {
        /**
         * x and y are shifted by half of the thickness given. If the thickness
         * is odd, it's evenly spread top, bottom, left and right for the given
         * x,y. Otherwise, extra one line for both top and left sides are added.
         */
        x -= thickness / 2;
        y -= thickness / 2;

        // Draw the lines from left to right first to fill horizontal space
        // Then move from top to bottom to fill vertical space.
        for (int i = 0; i < thickness; i++) {
            for (int j = 0; j < thickness; j++) {
                graphics.drawLine(x + j, y + i, x + j, y + i);
            }
        }

    }