void web_demo::load(const char* data_file_name)
{
    // Create the Geophile index for the data set.
    initialize_for_load();

    // Read a file containing box coordinates and colors.
    FILE* data_file = fopen(data_file_name, "r");
    int xlo, xhi, ylo, yhi, red, green, blue;
    while (!feof(data_file))
    {
        int n_fields =
            fscanf(data_file,
                   "%d/%d, %d/%d: %d/%d/%d",
                   &xlo, &xhi, &ylo, &yhi, &red, &green, &blue);
        if (n_fields > 0)
        {
            // Create a colored box with the specified coordinates
            // and colors
            box* b = new box(xlo, xhi, ylo, yhi, red, green, blue);

            // _space is the Geophile index representing the
            // data set. Add the box to it.
            _space->append(*b, b);
        }
    }
    // Indicate that there will be no more objects
    // added to the space.
    _space->input_complete();

    // Close the input file.
    fclose(data_file);
}

void web_demo::initialize_for_load()
{
    // Create the index to be used by the Geophile index.
    _index = disk_array::create(_db_name);

    // Describe the coordinate space.
    int lo[] = { 0, 0 };
    int hi[] = { _space_width - 1, _space_height - 1 };
    GF_space_description* space_description = 
        new GF_space_description(2, lo, hi);

    // Create the Geophile index by supplying 1) the data
    // structure to be used for recording index entries, and
    // 2) a description of the space. 
    _space = new GF_space(*_index, *space_description);
}