///////////////////////// Constructors //////////////////////

    /**
     *  This constructor, which takes no arguments,
     *  allows for future extension.
     */
    public Raster()
    {
    }

    /**
     *  This constructor creates an uninitialized
     *  Raster Object of a given size (w x h).
     */
    public Raster(int w, int h)
    {
        width = w;
        height = h;
        pixel = new int[w*h];
    }