Georg Baum wrote:
Am Sonntag, 26. November 2006 16:42 schrieb Abdelrazak Younes:
Well, it is not related to painting on screen, that's for sure. But it
might be related to font metrics calculation which is system dependent.
We are caching font width for normal text for example but for math
there's maybe more things that we need to cache. This is more related to
drawing than to painting in LyX terminology.
We are using font metrics to compute things like paragraph breaking in
rows and the resulting row heights. In the case of math, these info can
be pretty complicated to compute when you have fractions and integrals...
I doubt that computing the metrics of fractions or any math construct that
is not displayed by a font symbol is the problem, because this is done in
platform independant code in src/mathed/.
Ah? I didn't know that. Too bad, this would have been a very good
explanation. The thing is that the slowness happens only when typing
within the line following a big formula. I suspected that
redoParagraph() might be the culprit considering that csrss.exe is
apparently about the graphics subsystem. Now, I don't understand how it
comes into play.
AFAIK the metrics cache is used
for the symbol fonts too,
Indeed, well at least if they are in the ucs2 range and I think they are.
so I also doubt that symbol font metrics are the
problem. If for some reason the calculation of symbol font metrics would
be terribly slow on one platform then this should only be visible on
startup, and not anymore when the metrics cache is used. What we need is a
profile, but I currently don't have the time to look into this.
Yes, a profile is urgently needed. Un fortunately I don't have one on
Windows. If some user is willing to invest some time I can give some
good use case in order to find the problem.
Abdel.
