getting extents of individual words in a layout

[Theo Veenker <Theo Veenker let uu nl>]

Hi,

I need to know the extents of the individual 'words' in a layout
object (for an eye-tracking experiment). I want to draw a rectangle
around each word (in cairo) and also output the extents of each
word numerically.

Using an PangoLayoutIter I can walk over the layout lines and see
each character/grapheme but I how do I relate the current iterator
position to an index in the text? I need that in order to be able
to detect spacing characters between the words.

I also toyed with pango_layout_get_lines_readonly() and worked down
to the actual glyphitems but that seems rather tedious.

What would be the proper way to approach this?

Thanks,
Theo