virtual flat frame buffer

Howdy folks,

I've been playing around with *very* primitive graphics under Vsta
and I'd like to share as much code as I can between the operations
that work on memory bitmaps and the those that work on the screen.
One thing that would go along way to simplifying things would be
to setup a virtual flat frame buffer. The idea is that you memory
map the amount of memory you have on your video card and when you
try to read or write to a portion that isn't mapped in by the
page registers, a page fault is generated and the code to handle
video paging is invoked.

Has anyone done this already? If so, would you mind sharing your
code? If not, I'd appreciate anyone's suggestions on implementation
details. I'll probably start looking at it in a day or so.

thanks in advance,
eddier

-- 
   .__o   Ed McCreary            "The Information Superhighway, sanitized
 _-\ <,-  Compaq Computers        for your protection."
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