Re: More orca/m - flicker free animation

[andrep@balboa.eng.uci.edu (Andre Prellwitz)]

In article <3870.61.uupcb@uttsbbs.uucp> paul.parkhurst@uttsbbs.uucp
(Paul Parkhurst)  writes:

>One important thing about stack-based scrolling and graphic manipulation:
>you better make sure interrupts are turned off, or you'll get all sorts of
>corruption in your graphics (not to mention crashes)!  When an interrupt
>occurs, it pushes the current program counter onto the stack.  If the stack is
>pointed to the graphics page, you'll get random junk on the screen.

A problem a friend of mine had when doing this for a term program he wrote was
that when turning off interrupts, you could lose incoming data (from the
modem).  The solution?  Writing a "better" interrupt manager that made sure
the stack was pointing at the proper place before passing control to the
old vector routine.  Simple, yet a pain in the butt.  However, the screen
scrolls VERY fast (due to some other neat tricks as well) and makes ANSITerm
v1-2 look like it's running in slo-mo.