{
  "stage":
  {
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    "right":  0,
    "top":    0,
    "bottom": 0
  },

  "balls":
  [
    {
      "@count": 7,
      "img":    [ "@some", "tux", "owl" ],
      "r":      { "@min":  50, "@max": 75 },
      "x":      0,
      "y":      { "@min": 0.0, "@max": 1.0, "@relative": "vertical" },
      "vx":     { "@min": 250, "@max": 450 },
      "vy":     { "@min": 250, "@max": 450 }
    }
  ]
}