{ "init":
  { "pixiImages":
    [ "imgBackground", "imgOwl", "imgTux" ]
  },
  
  "model":
  { "stage":
    { "x":      0,
      "y":      0,
      "width":  "@width",
      "height": "@height"
    },

    "circles":
    { "number": { "@min": 15, "@max": 25 } },
  
    "circle":
    { "r":  { "@min": 25, "@max": 50 },
      "x":  { "@min": "@xMin", "@max": "@xMax" },
      "y":  { "@min": "@yMin", "@max": "@yMax" },
      "vx": { "@min": 100, "@max": 300, "@positive": 0.5 },
      "vy": { "@min": 100, "@max": 200, "@positive": 0.5 }
    }
  },

  "view":
  { "stage":
    { "image": "imgBackground" },
  
    "circle":
    { "image": ["@some", "imgOwl", "imgTux"] }
  }
}