{
  "version": "0.1",
  "nodes": {
    "1": {
      "id": 1,
      "name": "Block_60x40x20",
      "op": { "type": "Cube", "size": { "x": 60, "y": 40, "z": 20 } }
    },
    "2": {
      "id": 2,
      "name": "Center_XY_BottomOnZ0",
      "op": { "type": "Translate", "child": 1, "offset": { "x": -30, "y": -20, "z": 0 } }
    }
  },
  "materials": {},
  "part_materials": {},
  "roots": [
    { "root": 2, "material": "default" }
  ]
}