     root = makeTree network
     root = setNetworkPositions root, radius
 
+    @animate root, network_object
+
+  animate: (root, network_object) ->
+
     traverse = (node) =>
       return if ! node.position?
 
       node = @setTextObject(node)
       text_object = node._text_object
-      text_object.rotateX -rotation
+      text_object.rotateX -@rotation
       network_object.add text_object
 
       ################################

    line_layout = line_geometry.layout
    glyph_positions = line_layout.glyphs.map (g) -> g.position

    assert line?

    letterObjects = line.split("").map (letter, index) =>
      assert glyph_positions[index], "#{line} -- #{letter}"

              siblings = siblings.concat(node.parent.parent)
            promises = siblings.map (sibling) =>
              @fadeToArray(0, 1000) sibling._text_object.children
                .then -> network_object.remove(sibling._text_object)
            return Promise.all promises
        .then ->
          node.children.forEach traverse
