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From: C489030@UMCVMB.MISSOURI.EDU (Greg Hodgdon)
Newsgroups: comp.sys.apple2
Subject: Re: Smooth Scroll for Graphics in Assembly - How?
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Date: 10 Nov 90 09:58:08 GMT
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well, as long as you're using shape tables, you can completley eliminate
annoying flicker by using both hi res pages to do your animation:
Address $E6 tells the applesoft hires routines which page you're drawing
on: $20 for page 1, $40 for page 2.
  using this, you can draw/erase on the 'hidden' page while displaying
the previous screen.
  ie.  $C054   display page 1
       $E6:40  erase/draw on page 2
       $C055   display page 2
       $e6:20  erase/draw on page 1
       etc

a better (faster) way would be to use block shapes which erase themselves
as they're being drawn, but this involves either writing your own routines
for drawing and managing the shapes or using a package like the Graphics
Magician, which'll has a bunch of routines for doing all kinds of things
with shapes.  gee. whatever happened to penguin software anyway?

  ciao!

    greg hodgdon     c489030@umcvmb.missouri.edu

'The Grateful Dead use ORCA/M' - Mike Westerfield in a Nibble interview

p.s. marek P - I would'v responded in mail but i couldn't decipher that
               humongo address!