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