Obtains the position of the PangoLayout used to render text in the entry, in widget coordinates. Useful if you want to line up the text in an entry with some other text, e.g. when using the entry to implement editable cells in a sheet widget.
Also useful to convert mouse events into coordinates inside the PangoLayout, e.g. to take some action if some part of the entry text is clicked.
Note that as the user scrolls around in the entry the offsets will change. Remember when using the PangoLayout functions you need to convert to and from pixels using PANGO_PIXELS() or PANGO_SCALE.
The returned value is array($x, $x).