I want a subsurface to be the size/location that you ask it, even if
it overlaps/is outside of the parent surface. Any pixels that are
outside of the surface would be "dummy" pixels and any drawing to them
would be ignored. The idea is to be able to draw to a surface (0,
0)through(10, 10) and on the parent surface have it be drawing (-5,
-5)through(5, 5), and only (5, 5) --> (10, 10), which is (0, 0)
through(5, 5) on the parent surface, would actually be drawing to
non-dummy pixels. This might be really hackish though because what
then if you were to blit this subsurface to another surface, with its
dummy pixels? what would the dummy pixels show up as? I guess it
simply wouldn't copy them... as if you had asked it to blit a smaller
rect. I am mostly thinking about drawing aspect though...