[Libreoffice] Bringing some sanity to interline spacing

[Khaled Hosny]

On Thu, Sep 01, 2011 at 10:03:40AM +0100, Caolán McNamara wrote:
> On Wed, 2011-08-31 at 23:54 -0600, Tor Lillqvist wrote:
> > > The attached patch is an attempt to bring some sanity to the situation:
> > 
> > It seems that you have investigate this quite deeply and I would love
> > to commit and push your patch. However, I am a bit scared. Could
> > somebody else who actually understands the issues involved have a
> > look?
> 
> I think we're all too chicken to man-up and look at this one :-)
> 
> I guess the major fear isn't that your code is wrong, it's probably
> right, it's what stuff relying on the old way of doing things will
> change. I've been planning, but delayed on tracking down a mystery 2
> point offset :-), to put together a "did my layout change" regression
> test which would have been perfect to test this.

It is very likely to cause re-flowing (at least different line count per
page) for many documents, but on the other hand the old behaviour was
just wrong (and have been wrong for two decades now, since the
introduction of TrueType).

> caolan->tor: I suggest bunging this in for now, but putting the old
> algorithm behind an getenv(SAL_OLD_METRICS) or something for easy
> side-by-side testing ?
> 
> I'd be interested in knowing what effects the change has on typical
> fonts as opposed to the edge cases, i.e. does text rendered in
> Liberation Serif, Sans, Monotype stay basically the same.

I just tested with a simple lorem ipsum document with Liberation Serif;
page count went down from 24 to 22 after applying the patch, a quite a
drastic change I think :( One the bright side, I'm no longer getting
oversized buttons and combo boxes.

Regards,
 Khaled

-- 
 Khaled Hosny
 Egyptian
 Arab