Retrieve memory address range where the pixel data are stored at a given coordinates

[Giuseppe Torelli]

Hi,

suppose I have a range of coordinates x,y,width,height. How can I
determine the memory address range (start , end) where the pixel data
are contained at those coordinates?

I don't know If I have been clear, I need to compare that memory range
to detect changes in the root window (I know about XDamage extension).

Thanks,
P.S. can you please Cc the replies, I'm not subscribed to the list, thanks.

Giuseppe Torelli
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