You could write a set of helper/utility functions which wrap usage of
the IDirectFBSurface interface's Lock and Unlock functions.  Calling
Lock provides a pointer to the surface's raw pixels.  Unlock must be
called when you're finished updating the surface.
 
For optimal performance, I would try to find a good spot to call Lock
once prior to all of the individual pixel gets/sets, and another spot to
call Unlock afterwards.  I would also pay close attention to where the
surface memory resides (video or system) if a UMA (unified memory
architecture)-style platform is not being used.

Good luck!
 
Timothy 

________________________________

> From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] 
> On Behalf Of Francisco Sant'anna
> Sent: Tuesday, September 11, 2007 11:08 AM
> To: [email protected]
> Subject: [directfb-dev] Get/Set pixel color
>
> Hello,
>
> I need to bind with DirectFB an existing library that supports
functions to get and set single pixels in a canvas.
>
> The corresponding functions in DirectFB would be as follows:
>   GetPixelColor (IDirectFBSurface* thiz, int x, int y, u8* r, u8* g,
u8* b, u8* a);
>   SetPixelColor ( IDirectFBSurface* thiz, int x, int y, u8  r, u8  g,
u8  b, u8  a);
>
> I couldn't find a way to achieve this with the current API. 
> Are there any plans to support this?
> Or maybe there's a workaround that I missed.
>
> Thank you,
> Francisco 

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