public void init( ) {
        // initialize the off-screen rendering buffer
        width = size().width;
        height = size().height;
        screen = createImage(width, height);
        gc = screen.getGraphics();
        gc.setColor(getBackground());
        gc.fillRect(0, 0, width, height);

        fov = 30;                         // default horizonal field of view
        // Initialize various lists
        objectList = new Vector(CHUNKSIZE, CHUNKSIZE);
        lightList = new Vector(CHUNKSIZE, CHUNKSIZE);
        currentSurface = new Surface(0.8f, 0.2f, 0.9f, 0.2f,
                                     0.4f, 0.4f, 10.0f, 0f, 0f, 1f);
        // Parse the scene file
        String filename = getParameter("datafile");
        showStatus("Parsing " + filename);
        InputStream is = null;

        try {
            is = new URL(getDocumentBase(), filename).openStream();
            ReadInput(is);
            is.close();
        } catch (IOException e) {
            showStatus("Error reading "+filename);
        }