Hi
How can i avoid flickering in Photon application ?
I have several windows in my application and each windows
have several number of bitmaps ( i dont use images).
When application switch between windows, there exists flickering !!
Is possible to use some kind of “sync” ?
Esa
There are different causes for flickering. Once possible cause
is a very slow video card. There’s not much you can do about
it other than upgrade.
Another frequent cause of flickering is the use of transparency
maps. When you use a transparency map, Photon doesn’t know ahead
of time where the background will show through, thus it uses a
painters algorithm for reshowing. At least this is what Photon
did in version 1.4. Another “feature” of 1.4 was that widgets
in a window would be displayed using the painters algorithm.
If you have many overlapping widgets, the result can be
pretty ugly. One way of dealing with this difficulty is to
unrealize any widgets that you know will be invisible. I
was told this might be improved in a later version of Photon
2.+ but I don’t know if it has occured. Another related
problem occurs when widgets are displayed in a haphazard
way. This can be controlled to some degree. One way I found
was to put widgets that you want displayed together on a
frame. When you realize the frame, or it gets reshowed,
those widgets will be displayed together.
Finally, there is the double buffer widget. Under 1.4 it
limited the number of colors you could use successfully.
That is the direct modes did not work at all. This too was
supposed to be improved in 2.0, but I haven’t checked.
Mitchell Schoenbrun --------- maschoen@pobox.com
-use a PtOSContainer to group your bitmaps together.
this widget is doing all its output into a offscreen context first off all,
and aftwards the memory is moved at once.
-also define your PtImage_t to use shared memory, this will speed up the
transfer of the Image between the offscreen context and the visible memory
part.
-also go ahead to the Photon documentation
http://qdn.qnx.com/support/docs/photon_2.0_en/index.html
/hp
“Esa Heikkinen” <esa.heikkinen@insta.fi> schrieb im Newsbeitrag
news:a338l9$qpi$1@inn.qnx.com…
Hi
How can i avoid flickering in Photon application ?
I have several windows in my application and each windows
have several number of bitmaps ( i dont use images).
When application switch between windows, there exists flickering !!Is possible to use some kind of “sync” ?
Esa
Where can i find Photon version 1.4 or (2.0) ?
Is that only for QNX6 (Neutrino) ?
Esa
Mitchell Schoenbrun wrote in message …
There are different causes for flickering. Once possible cause
is a very slow video card. There’s not much you can do about
it other than upgrade.Another frequent cause of flickering is the use of transparency
maps. When you use a transparency map, Photon doesn’t know ahead
of time where the background will show through, thus it uses a
painters algorithm for reshowing. At least this is what Photon
did in version 1.4. Another “feature” of 1.4 was that widgets
in a window would be displayed using the painters algorithm.
If you have many overlapping widgets, the result can be
pretty ugly. One way of dealing with this difficulty is to
unrealize any widgets that you know will be invisible. I
was told this might be improved in a later version of Photon
2.+ but I don’t know if it has occured. Another related
problem occurs when widgets are displayed in a haphazard
way. This can be controlled to some degree. One way I found
was to put widgets that you want displayed together on a
frame. When you realize the frame, or it gets reshowed,
those widgets will be displayed together.Finally, there is the double buffer widget. Under 1.4 it
limited the number of colors you could use successfully.
That is the direct modes did not work at all. This too was
supposed to be improved in 2.0, but I haven’t checked.Mitchell Schoenbrun --------- > maschoen@pobox.com