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From: micro@imada.ou.dk (Klaus Pedersen)
Newsgroups: comp.sys.atari.st.tech
Subject: Bug in Overscan software.
Message-ID: <1991May14.193547.29278@imada.ou.dk>
Date: 14 May 91 19:35:47 GMT
Sender: news@imada.ou.dk (USENET News System)
Organization: Dept. of Math. & Computer Science, Odense University, Denmark
Lines: 30

There have been some talk about Overscan here lately, that reminded me
that I found 2 bugs in the driver software. The bugs are in the same 10
lines of code, and they are kind of strange! 
The scene is the following: 
AES initializes itself and opens a Screen workstation. Overscan sits in
the AES/VDI trap and checks for that call, and let it run, after it have
run Overscan initilizes the LineA varibales, (in Do.something). 
At this point Overscan wants to change the variables in your WorkOut array, 
this is where things go wrong

1. (this is the worst) it puts the width and height of the screen into
WorkOut[0] and WorkOut[1] instead of the highest addressable cell (width-1
and Height-1).

2. it tells that you have 200 colors in color mode, and not $200(or 512).

Note that these errors overrides the values put into the LineA varibales
that otherwise are good enough.

Then why don't I release my version? 
- Overscan is Commercial now so I don't know if it's legal. Also my version 
have been hacked so much that it probaly have even more errors. 
(I have taken the illigal fidling with the allocated memory lists out and 
removed compability with prehistoric TOSes) - so you probaly don't want it 
anyway... 
How can we fix this problem - I guess that Karsten will tell us that he have
a fix (called autoswitch Overscan).


Klaus, micro@imada.ou.dk