From: karna AT pobox DOT upenn DOT edu (Animesh Karna)
Posted-Date: Sun, 12 Jul 92 19:46:28 EDT
Subject: Video modes and some distribution questions
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Date: Sun, 12 Jul 92 19:46:28 EDT


I have some questions regarding djgpp (I believe the version I am using is
version 1.06) . . .

I am under the impression that, if I executed the BIOS interrupt to change
video mode, it will switch into one of the modes supported by the current
driver (for example, the "text mode", "320x200 mode", "highest res mode"),
instead of switching into the actual BIOS video mode.  Is there a way to fix
this?  

I am thinking about porting a pgm to djgpp, but it uses a 16-color
graphics library.  The lib should work providing I can write to certain
ports and I can access video mem at 0xA0000.  But, I need to be able to 
switch into 640x480x16 graphics mode.  I know that the grx lib does this, 
but I'd rather not have to rewrite this pgm to use that library.

Before I port this pgm, I have some questions regarding distribution of 
this pgm.  I am writing this for my work, and this pgm will be sold 
commercially.  I doubt my bosses would be too hot for the idea of 
releasing this pgm free ;-).  I understand that we can distrib stuff
commercially providing we pay some percentage.  Is this a percentage of
the selling price per copy, or a percentage of the total amount sold?
BTW, I imagine that the pgm .EXE file will be created by appending the 
a.out file to GO32.EXE, since that appears to be the fastest loading.

Parts of the library are covered by the Gnu license, if I understand 
correctly, and if we use these fcns our pgm must be distributed according
to the Gnu license.  Needless to say, my bosses wouldn't be too hot with
that idea, so I think it would be prudent for me to avoid using those
fcns.  Can someone tell me exactly what parts of the library I should 
avoid using to avoid this situation?

Thanks!
-A.K.