List<Float> currVertices = new ArrayList<Float>(); // the vertices of the current province
for (int y = 0; y < worldImage.getHeight(); y++) {
     for (int x = 0; x < worldImage.getWidth(); x++) {
           if (!currColors.contains(worldImage.getRGB(x, y))) {
                  if (!currVertices.isEmpty()) provinceVertices.add(Utils.toFloatArray(currVertices)); // store the current province's vertices into the total database
        currVertices.clear();
           }
       if (x%4==0) currVertices.add((float)(x)/EngineManager.getWindowWidth());
       if(y%4==0) currVertices.add((float) (y)/EngineManager.getWindowHeight());
     }
 }

public static float[] toFloatArray(List<Float> list) {
        float[] array = new float[list.size()];
        ListIterator<Float> iterator = list.listIterator();
        while (iterator.hasNext()) {
            array[iterator.nextIndex()] = list.get(iterator.nextIndex());
        }
        return array;
    }