The approach Damir is suggesting is called "double buffering" and it 
really is something that I had used in my palm applciations to 
avoid "flickers". 

Basically you create an off-screen and perform all your oeprations on 
it. Then when you wanna update your "on-screen" or the main UI/LCD, 
you copy the screen contents from off-screen to on-screen. This 
technique has some limitations viz. due to the restriction of the 
offscreen window size. But with some good logic, you can overcome 
this limitation.

Furthermore, if the updates that you are doing on on-screen involve 
small areas, then instead of updating the entire 160X160 pixels, you 
could "clip" those small areas and copy it on on-screen.

Thanks.

-Viren


--- In [EMAIL PROTECTED], Damir <[EMAIL PROTECTED]> wrote:
> Hi, Mike.
> I am using another method:
> 
> 1. Make my offscreen window
> 2. When I need to draw, I set DrawWindow to my window
> 3. Make drawing all I need
> 4. Set DrawWindow back to screen window
> 5. Copy my window to screen window
> 
> It works fine.
> Damir.
> 
> 
> MM> Hi,
> 
> MM> I am tyring to write my own WinScreenLock/Unlock to prevent 
screen flicker but
> MM> am having some problems.  When I have "locked" the screen by 
using
> MM> WinSetDrawWindow I still have stuff writing to the screen and 
not to my
> MM> offscreen window.  Also, when the user minimizes or maximizes 
the graffiti
> MM> area, it does not seem to track.  I've included some code below 
to show what I
> MM> am doing.  I have a feeling that I am missing some baisc 
problem.  Anyone have
> MM> any ideas?
> 
> 
> 
> 
> -- 
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