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From: rbannon@cosmos.acs.calpoly.edu (Roy Bannon)
Newsgroups: comp.sys.apple
Subject: Re: Apple II Video Overlay Card
Keywords: Piracy
Message-ID: <1989Nov20.215920.20872@polyslo.CalPoly.EDU>
Date: 20 Nov 89 21:59:20 GMT
References: <879@oucsace.cs.OHIOU.EDU> <9075@microsoft.UUCP> <36617@apple.Apple.COM> <1989Nov19.061014.10847@uokmax.ecn.uoknor.edu> <36654@apple.Apple.COM> <5266@sdcc6.ucsd.edu>
Sender: news@polyslo.CalPoly.EDU (News Guru)
Reply-To: rbannon@cosmos.acs.calpoly.edu.UUCP (Roy Bannon)
Organization: Cal Poly State University -- San Luis Obispo
Lines: 33

Okay folks, I guess I'll throw my two cents in.  I have a VOC and I made the 
silly thing do 640x400.  The bad news first.  As Matt said, the odd(or is it
even) scan lines are right on top of the memory managers unmovable handles.
So when you make the toolcalls to enable 640x400, it displays the handles on 
the odd (or even) scan lines.  Ok you say, replace the handles with the picture.
Right you are, but then if you use any tools or gs/os with your picture there

instead of the handles, yep you guessed it, system crash.  So all the program
I wrote did was load the picture, make the appropriate tool calls, move the 
pict into memory (by hand not using mem manager) wait a while, move the
handles back.  Since the video was interlaced, the image shook a little bit.
For digitized pictures without sharp edges, this wasn't all that bad.  For 
computer images with sharp lines, it wasn't all that great.  

Why they did it in the first place if it can't be used in the presence of
anything that uses the memory manager.  It's my understanding thats it's
very easy too do in hardware, so why not.  The card has to generate interlace
video, so on the odd frames, why not switch banks an display new data.  This
gives the 400 vert lines.


My idea is for apple to write a new memory manager.  Does anyone except the
memory manager need to know the abs location of the handels.  The only
ones I can think of are the utility programs that give info about all handles
allocated and such.  So why can't the move them somewhere else.  Atleast
the 400 lines could the be used a little bit.


If there is any interest about the program for 400 line resolution, send
me email.

Roy
rbannon@cosmos.acs.calpoly.edu