BitBlt flicker

[ulrike96]

Hi,all,
I wrote a program that let's you move a circular
region across the screen with the mouse; in this circular region, the RGB values are changed to corresponding
values of a bitmap in the backbuffer. A BitBlt is made whenever there is a change of more than 8 Pixel on the screen. However, with these settings, there appear horizontal white lines in the region once or twice
a second. Increasing monitor frequency does not help.
When I increase the cut-off from 8 to, e.g., 80 Pixel, the flicker disappears. Does someone have an idea as to what I could do to get around this (DirectX ???).
Thanks !

 

[PerFnurt]

It is not the BitBlt that generates the flicker but rather the erasing of the background.

See

http://codeguru.earthweb.com/misc/flicker_free_drawing.shtml

I use an optimized version of this myself.


/Per
[sub]
if (typos) cout << &quot;My fingers are faster than my brain. Sorry for the typos.&quot;;
[/sub]

 

[palbano]

DirectX is certainly what you want to use for real time (games/screensavers etc.) graphics intensive operations.

-pete