root:
  items:
    - image: xy-gradient(512, 512)
      bounds: 0 0 512 512
      stretch-size: 512 512
      tile-size: 64
    - image: xy-gradient(512, 512)
      bounds: 512 0 512 512
      stretch-size: 512 512
      tile-size: 128
    - image: xy-gradient(512, 512)
      bounds: 0 512 512 512
      stretch-size: 512 512
      tile-size: 256
      # tile size bigger than the image itself
    - image: xy-gradient(512, 512)
      bounds: 512 512 512 512
      stretch-size: 512 512
      tile-size: 4096