As I just pointed to Koen on IRC, there's some nice code in Cairo for fast double-to-fixed conversion [1]. This might mitigate that slowdown.
Thanks, Rob Taylor [1] http://gitweb.freedesktop.org/?p=cairo.git;a=blob;h=fe6c2dc3ee545442286aef3e3291a24dde39733c;hb=eec62c297589ca20f4128c889ecad9e96736a07f;f=src/cairo-fixed.c Matt Hoosier wrote: > I don't have the work on-hand any more, but a colleague of mine tried > just this a few months ago. > > The results (according to gtk-theme-torturer exercising a theme which > used pixmaps) were somewhat disappointment. If I remember correctly, > there is currently only a small bit of non-integer math remaining in > pixops.c (calculation of the filter, or something like that). At the > time, our speculation was that the overhead to cast the floating point > inputs into fixed-point was dominating any savings to be had from > avoiding this small amount of software FP emulation. > > On 2/10/07, Koen Kooi <[EMAIL PROTECTED]> wrote: > [also posted to openmoko-devel, but I'm too stupid to figure out how to > mix&match gmane > nntp and regular email] > > > Hi, > > A few years ago Phil Blundell made patch[1] to speed up pixel operations > (scale, blend, > rotate, etc) a lot for systems without a floatingpoint unit. Years of gtk+ > developer > desinterest have let the patch bitrot a fair deal. > In order to get the ball rolling again I updated the autotools bits in the > patch and > adjusted the indices so it applies to the .c files as well. What's left is > updating the > functions and their arguments to catch up with several years worth of > development. > This patch would speed up the GUI on openmoko based systems a lot, since it's > using quite > a lot if pixmaps. > > I've heard that the openmoko team also tried sapwood, but couldn't get it to > work properly > because it's a) entirely undocumented and b) only supports 1 bit alpha > > Any heroes that want to give a shot at updating the pixops patch? > > regards, > > Koen > > [1] http://bugzilla.gnome.org/show_bug.cgi?id=90621 > >> _______________________________________________ Performance-list mailing list [email protected] http://mail.gnome.org/mailman/listinfo/performance-list >> > _______________________________________________ > Performance-list mailing list > [email protected] > http://mail.gnome.org/mailman/listinfo/performance-list _______________________________________________ Performance-list mailing list [email protected] http://mail.gnome.org/mailman/listinfo/performance-list
