A89: Re: 5 level grayscale

To: <assembly-89@lists.ticalc.org>
Subject: A89: Re: 5 level grayscale
From: "Scott Noveck" <noveck@pluto.njcc.com>
Date: Tue, 23 Feb 1999 21:08:40 -0500
Delivered-To: assembly-89-outgoing@towerguard.unix.edu.sollentuna.se
Delivered-To: assembly-89@lists.ticalc.org
Reply-To: assembly-89@lists.ticalc.org


It wouldn't do much good considering the way Greyscale works on the
calculator -- two-plane greyscale (one plane for each level and mixing for
black) has a maximum of 4 shades (bit set in neither plane, the first plane,
the second plane, or both planes) created by flipping through the two planes
with one plane showed 1/3 of the time and the other 2/3 of the time.
Anything more than 4-level greyscale requires a third plane, meaning a hefty
increase in file size (and another heap allocated to the buffer, meaning
more free RAM required to run it), and the increased number of switches
required (one plane shown 1/4 of the time, another 2/4 and the third 3/4)
increases flickering.  The only way to get 5-level greyscale would be using
a 7-level routine with only 5 colors used.  Hence the reason that there are
only 4-level and 7-level greyscale libraries:  These can be used with fewer
greys with no change at all, and making any libraires supporting 10-level
greyscale would make programs rediculously huge and flicker too much to be
of much use.

        - -- Scott Noveck (SMN)

>Date: Tue, 23 Feb 1999 19:00:33 EST
>From: ManjiLump@aol.com
>Subject: A89: 5 level grayscale
>
>I was wondering how hard it would be to make a 5 level grayscale program.
Also
>how much would this flash back and forth, hopefully not as much as in the 7
>level grayscale.
>- -Manji