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From: youngdahl@gacvx1.gac.edu
Newsgroups: comp.sys.apple2
Subject: Extended graphics on the IIgs (?)
Message-ID: <1991Jan18.004931.1@gacvx1.gac.edu>
Date: 18 Jan 91 06:49:31 GMT
Organization: Gustavus Adolphus College, St. Peter, Minnesota
Lines: 36
Nntp-Posting-Host: gacvx1
Nntp-Posting-User: youngdahl

Ok, I posted a message on this subject earlier with sort of a "rediculous"
subject line, and nobody replied... so I'll try it again...

Does anyone know if it is possible to:

1.  Achieve a 32 color grey scale by "bleeding" together the current 16 color
    grey scale.  i.e.  You display the following the first time the computer
    refreshes the screen:

    black black grey1 grey1 grey2 grey2 ... grey14 grey14 white white

    and then change the scan line to:

    black grey1 grey1 grey2 grey2 grey3 ... grey13 grey14 grey14 white

    thus creating the illusion of 32 shades of grey to the naked eye??
   
    I think I read about this being illustrated in some demo somewhere, but I
    have yet to see it.  I mean, even if the overhead is very high on the CPU,
    and there is a slight flicker, it would be nice for displaying GIFs that
    utilize a high number of colors in B/W.

2.  If the above is possible, then it should also follow that one could change
    between 2 different sets of 16 colors on a line and change a few pixels in
    that line to achieve the illusion of 32 colors/line...

    right?

3.  If the gs can display 640x200x"800" and 320x200x"3200", then it should also
    be able to split 3/4 of the screen into 320x200x"3200" and the bottom 1/4
    into 640x200x"800", right?  This would be great for an adventure game, with
    limited/no animation  ...  good graphics and 80 column text below...

Ben

youngdahl@gacvx1.gac.edu