code: function repositionModel(scene) {
    var n = State.gridSize
    var i = State.scenes.length
    var x = 2 * (i % n) - n + 1
    var z = 2 * Math.floor(i / n) - n + 1
    if (State.selectedModel) {
      x = z = 0
    }
    scene.root.transform.set({
      position: [x, scene.root.transform.position[1], z]
    })
  }
docs: renderer.add(lineBuilder) glTF