From: josepva AT informatica DOT TELERJ DOT net DOT br
Message-ID: <39AE1D927549D111A88F00A0C94B9C7D7120BD@rj01mai01.informatica.telerj.net.br>
To: djgpp AT delorie DOT com
Subject: RE: Mouse in SVGA Mode
Date: Wed, 24 Feb 1999 16:35:45 -0300
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> ----------
> De: 	Shawn Hargreaves[SMTP:ShawnH AT Probe DOT co DOT uk]
> Enviada: 	Quarta-feira, 24 de Fevereiro de 1999 14:11
> Para: 	djgpp AT delorie DOT com
> Assunto: 	Re: Mouse in SVGA Mode
> 
> josepva AT informatica DOT TELERJ DOT net DOT br writes:
> > I know that it's not a problem, I don't know why it works this way
> > but it is the way that it should be. I know that 320x200 resolution 
> > work in that way i don't know who is the other resolutions that it 
> > happens, maybe you have to try by your own.
> 
> Be very careful about using this sort of try-it-and-see approach with
> a mouse driver, because not all drivers are created equal. Some are
> buggy, while others are just weird :-)
> 
> To the best of my knowledge, the current Allegro mouse code works 
> correctly with any DOS mouse driver on any SVGA board, but the only
> way I was able to do this is by using only the mickey motion counts
> from the driver, and writing all my own code for tracking the 
> position and displaying the cursor. Back when I was using the int 
> 0x33 functions to do these things, I was unable to find any method
> that would work reliably for everyone.
> 
	...  The Voice of Knowledge ...

	I really never got realiable work when playing with DOS mouse
drivers and graphics. I think the method apresented above is the best one if
you really want a realiable program and if you are trying to do something by
your own use that, or use Allegro (that encapsulates everything and makes
life easier).


José Paulo
Rio de Janeiro - Brazil