so, is this claim about pango still true? or does nobody actually care?

We are about 60% of the way through porting Ardour, probably the premier
digital audio workstation for Linux (winner of Linux Journal's Best
Project prize for 2005, and other awards) from GTK1 to GTK2. Today,
someone sent me this email:

sorry to bug you directly, but I caught a post of yours on slashdot
ardour being ported to GTK=2.x  I did that to some of my apps and hit
things that may cause you problems.  Teh main thing is it's about 3-12x
and text rendering is the primary problem. (the main fault isn't
necessarily in
GTK+ (though it IS slower and more bloated in the 2.x trees) it's with
IF you have any fields that need to render text and change it often,
find that it consumes and exhorbitant amount of CPU.  I've traced this
issue in
my own code. (not nearly complex as anything like ardour) and pango was
culprit, bugs were filed and fell on deaf ears (owen taylor) and nothing
been done over the past 3 years.  I've since decided that QT-4 was a
route. (requires a LOT of work for me,  but in the end the gui will be
far more
flexible and faster, and much easier for me to run on multiple platforms
including win32)

Just thought you'd want to know that there are some significant
concerns on GTK+-2.x.  As a reference the perf issue I was having was
evident when updating a textual label (reporting some ADC value) at a
rate (10x per second or so).  Updating 5-10 labels at h the above rate
was reporting data for an outside slow-speed data acquisition system)
in cpu usage of over 40-60% on a 1200 mhz processor.  All other major
were disabled in the program to make 100% sure that the text rendering
causing the problems.  gprof'ing the executable pointed to calls in
pango (a
large number of them eating a little for each function, but that added
up to
horrible performance).  GTK+-1.x doesn't have this issue as it used core
fonts and that is screaming fast.  QT doesn't use pango it uses
somethign else
but it didn't seem to show any appreciable cpu usage for a similar

is this still true? does anybody care? is there a way to avoid pango
entirely and still get AA fonts inside GTK2? will this ever be fixed
before everyone is using h/w acceleration to print button labels?

the issue raised here will *kill* ardour dead, and would force us to
also have to abandon GTK for Qt (a move I would really, really not want
to make). some clarification would help ....


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