Re: getting extents of individual words in a layout

[Behdad Esfahbod <behdad behdad org>]

On Tue, 2008-02-19 at 22:33 +0100, Theo Veenker wrote:
> 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.

You are on the right track.  What's missing is an API to iterate over
glyphitems.  That code exists in Pango internally.  See:

  http://bugzilla.gnome.org/show_bug.cgi?id=377948

It's pretty short.  I suggest you copy/paste it for now.

When you get back to character offsets, you can use
pango_get_log_attrs() results to find word boundaries, etc.


> What would be the proper way to approach this?
> 
> Thanks,
> Theo

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behdad
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