Xref: utzoo comp.sys.mac.programmer:1725 comp.sys.mac:18558
Path: utzoo!attcan!uunet!husc6!uwvax!oddjob!gargoyle!att!ihnp4!poseidon!ech
From: ech@poseidon.UUCP (Edward C Horvath)
Newsgroups: comp.sys.mac.programmer,comp.sys.mac
Subject: Re: MAC II video enabling/disabling?
Message-ID: <457@poseidon.UUCP>
Date: 22 Jul 88 16:46:08 GMT
References: <578@sdics.ucsd.EDU>
Organization: AT&T Information Systems, Lincroft, NJ
Lines: 20

> Xref: poseidon comp.sys.mac.programmer:1518 comp.sys.mac:18930


> Does anyone know an easy way to turn on and off the whole
> video display on the MAC II (we have the MAC II color video
> monitor, with color upgrade, if that's relevant)?
> We want to be able to draw a screen full of images (which will
> take us several hundred msec), and display this screen full
> instantaneously (i.e., within a single refresh), and to be
> able to turn the whole thing off equally quickly.

On a 4- or 8-bit video board, you can do the job with a degenerate form of
color animation: use the Color Manager's SaveEntries trap to save the color
table, set every color to black, draw your image, then RestoreEntries.

The last step essentially consists of setting 256 longWords on an 8-bit board,
and really ought to look pretty well instantaneous, i.e. should be able to run
completely between frames.

=Ned=