# An example input file to draw concentric spherical shells

region: "
  (-[x^2 + y^2 + z^2 - 1] & +[x^2 + y^2 + z^2 - 0.5])
  |
  (-[(x-2)^2 + y^2 + z^2 - 0.75] & +[(x-2)^2 + y^2 + z^2 - 0.25])
  "
bounds:
  min: [-5, -5, -5]
  max: [5, 5, 5]
resolution: [100, 100, 100]