Re: [Devel] compute bounding box

[Tom Kacvinsky]

Well, it is in the TODO list that computing the bbox of a glyph that uses cubic
Bezier curves is broken.  Given the fact that you may want to use the bbox of
each glyph shown in a string to compute the glocabl bbox of the string, I'd have
to say that you are going to have problems with Type 1 fonts. :(

But, supposing the glyph bbox code for each font format FreeType supports works 
and
assuming a left to right (or right to left) language script:

The height of the global bbox should be the maximum of

   {y: y is the "height" of the bbox of a glyphs shown in the string}

Similarly for the depth of the global bbox.  The left (right, resp.) edge is a
rather simple case:  the left (right) edge of the first glyph shown (if kerning
isn't wacked out).

The right (or left) edge poses a problem, because the advanced width, kerning,
and left side bearing tricks that can come into play.  I leave that up to the
interested reader. :)

Tom

P.S.  Thierry, did the ASCI85 code I pointed out to you (on comp.text.pdf) work
out?



On Tue, 17 Apr 2001, Thierry Frey wrote:

>
> I was interested in using freetype to compute the bounding box of a given
> string. Unfortunately, the FAQ only hints at this at the moment. Does
> anybody have a more thorough answer? I'd be happy to write up something for
> the FAQ afterwards.
>