surface pattern - what is wrong?

I am trying to divide surface into 4 groups with pattern as shown in the image.

Could you tell me what is wrong with my definition?

surface%20pattern_f.gh

  • up

    JS

    Have you tried relative item?

    • up

      Nick

      have not looked at JS's solution, but here's mine.

      • up

        Michael Pryor

        try this simple way