new_w = w * 0.8;
     w = some_number;
     h = some_number;
     for (int i = 0; i < num_rectangles; i++)
     {
         cx = some_data[i * 2];
         cy = some_data[i * 2 + 1];
         if (cx < w && cy < h)
         {
            new_w = max(cx * 2, new_w);
         }
     }