>> Given that frame buffer memory access tends to be significantly
>> slower than regular memory access, it may make sense to re-render
>> the text into the new frame buffer location rather than do a
>> frame-buffer to frame-buffer copy.

It doesn't make sense to hardwire that assumption.  Some hardware can
be told to do blits within framebuffer memory very fast, even if
cpu-to-framebuffer access is slow.  (Sun's cg6 is an example; scrolling
got *immensely* better when I taught it to use the hardware...using
knowledge, incidentally, gained writing a game.  Never let it be said
games are useless. :-)

> That requires storing the character cells somewhere.

Well...it involves storing the character code information necessary to
re-render.  It doesn't necessarily involve storing the rendered bitmap.
And a screenful of characters is only what, maybe a few thousand bytes?
Surely not enough to worry about.  You need it for scrollback anyway.

					der Mouse

			       mouse@rodents.montreal.qc.ca
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