public function merge(Color $color1, Color $color2, $percentage = 50)
    {
        return new Color(array(
            'red' => $this->getMergedColorPart('red', $color1, $color2, $percentage),
            'green' => $this->getMergedColorPart('green', $color1, $color2, $percentage),
            'blue' => $this->getMergedColorPart('blue', $color1, $color2, $percentage)
        ));
    }