Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!jarthur!nntp-server.caltech.edu!toddpw
From: toddpw@nntp-server.caltech.edu (Todd P. Whitesel)
Newsgroups: comp.sys.apple2
Subject: Re: Synnovision
Message-ID: <1991Apr20.060038.22563@nntp-server.caltech.edu>
Date: 20 Apr 91 06:00:38 GMT
References: <9104200324.AA14018@apple.com>
Organization: California Institute of Technology, Pasadena
Lines: 31

dlyons@APPLE.COM (David A. Lyons) writes:

>The main part of the problem is that a large fraction of commercial and
>other applications *bypass QuickDraw* and write directly to the screen.

>If this problem were solved, then using 640x400 on the video overlay card
>would be a problem because everything drawn would be squashed to half
>height.  (On the mac you always have square pixels; resolution changes
>but aspect ratio does not.)

Two things: I do not care about using the VOC for desktop stuff. I have
no wish to squint or buy sunglasses or whatever because of the flicker.
I want info on Supervisor drivers so I can write one to arbitrate for use
of the second VOC video buffer for a subtitler and a picture viewer.

QuickDraw support would better be spent on a 640x400 VGA card that does 16 or
more colors and fools the toolbox into thinking it is in 320 mode with the
palette calls modifying a subset of the truly available colors.

Eventually, GS/OS drivers following a naming and calling convention could be
used to expand quickdraw's internal 1 bit images onto the hardware in the
current pixel depth. Correct me if I'm wrong, Dave, but Quickdraw internally
renders nearly everything in 1 bit and then copies it to the screen while
expanding the pixel depth on the fly (using tables or some such). A video
card that would let you write 1 bit images to it and automatically write 1's
or 0's (or both) to memory from foreground and background color registers
would be really cool and it would speed up one thing about QD that makes
text rather slow to render.

Todd Whitesel
toddpw @ tybalt.caltech.edu