public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof PiePlot3D)) {
            return false;
        }
        PiePlot3D that = (PiePlot3D) obj;
        if (this.depthFactor != that.depthFactor) {
            return false;
        }
        if (this.darkerSides != that.darkerSides) {
            return false;
        }
        return super.equals(obj);