Difference between win32gdk and win32: TExec performance

I’ve noticed a significant performance difference between win32 and win32gdk (using 3.10/0 sources dated October 02, 2003, 10:18 AM.) I’ve attached a script that illustrates the problem: It generates a 2D histogram and my TExec() (used gPad->AddExec(“ex1”,“event()”) superimposes a circle that is sized dynamically. Perhaps it not the right way to do it and I’m willing to do it differently. To run the script (I borrowed histogram filling fron tutorials/fit2.c), do the following:

.L demo.c Start()
Then button-down on a point on the TH2 - this will fixes a point on the circle. Dragging positions an antipodal point and button-up terminates the TExec. Note: in my actual implementation, everything is compiled and the effect is just a pronounced.
Is the problem with my code? Or is it as problem with win32gdk? Thanks for you help!

Ed Oltman
demo.c (2.28 KB)

Hi Ed,
we’re working hard on improving performance (canvas graphics)
of win32gdk, for example ROOT 3.10 is ~3 times faster than 3.05.07
and comparable with Linux (same CPU). I hope/expect it will be
more improved in the nearest future. The main advantage of
win32gdk against win32, it’s “linux compatible” and provides
the same API for GUI.

Thank you for posting your example. I’ll investigate it.

Regards. Valeriy


We are aware that some painting options for TH2 is still 3 to 4 times slower than the old win32 version. The speed is quite acceptable
for the vast majority of our applications. In your case, your script
is attempting to redraw a 100x100 plot a few times per second.
Not too bad! but I agree that it would be nice to gain another factor 2 or 3.