I’m trying to implement a game that makes heavy use of scrolling;
hence I need to blit from the same surface to itself from different
rects of itself. Now, is this safe if the rects of the surface overlap?
Is it even safe to blit from and to the same surface? If not, could you
perhaps add provisions for this and make the documentation more clear
on this?
It’s not safe to perform overlapping blits, unfortunately.
There are about 30 blit functions that need to be modified to accomodate
this. I will clarify the documentation.
Would you like to implement overlapping blits? 
-Sam Lantinga (slouken at devolution.com)