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From: ormohrbh@ubvmsd.cc.buffalo.edu (Richard Ohrbach)
Newsgroups: comp.lang.pascal
Subject: Graphics problem
Message-ID: <59173@eerie.acsu.Buffalo.EDU>
Date: 11 Feb 91 22:48:39 GMT
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I am having the following problem:
     I developed a program on computer #1 (8088 machine) which contained 
the following sequence of code:  SetViewPort (#1); 
				 write some stuff in this viewport
				 SetViewPort (#2);
     				 write some stuff in this viewport

The program worked fine when initially developed, and it still does on 
computer #2 (80386) as well as another 8086 machine, but the program does 
not work on computer #1 or two other 8088 machines.  The problem is this: 
when ViewPort #2 is initialized, the program returns back GraphResult of 
-11 ("GraphicsError"), and the stuff that is supposed to be done in 
ViewPort #2 is done instead in ViewPort #1.  So, ViewPort #2 is not 
recognized.

I called Borland tech support, who suggested that the problem was memory 
corruption.  Following their advice, I turned Range Checking ON, and, 
unfortunately, that did not catch the corruption.  I then commented out 
every procedure in the program that was not essential to this particular 
section of code, and still the problem remains.

My question, as a non-professional programmer, is what is the best thing to 
do at this point, given that the code runs on some machines and not others 
(and the code has to be able to run on the 8088 machine) ?  Should I 
rewrite the unit from the ground up, or is their some other less painful 
way to solve this problem?  

Thanks for any help...
Richard Ohrbach
University at Buffalo
ormohrbh@ubvms.bitnet