anchor: Text:getHeight
  Gets the height of the text in pixels.
  height = Text:getHeight()
  height number The height of the text. If multiple sub-strings have been added with Text:add, the height of the last sub-string is returned.
  height = Text:getHeight( index )
  index number An index number returned by Text:add or Text:addf.
  height number The height of the sub-string (before scaling and other transformations).