From:	Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: allegro - sprites and smudge on screen
Date:	Wed, 19 Mar 1997 19:37:24 +0000
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Distribution:	world
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	<199703190811 DOT JAA23035 AT gilberto DOT physik DOT rwth-aachen DOT de>
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To:	djgpp AT delorie DOT com
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Christoph Kukulies writes:
>Could the interrupt routine save the SVGA bank and restore it back? Or
>would that be too slow or impossible? Or is my question totally off

This would be possible, but it wouldn't address the problem where the
item you are drawing actually overwrites the current mouse sprite. The
only way to handle that automatically would be to make every single
drawing routine check whether it overlaps with the cursor, and such
tests would cause a huge performance hit. I think this is really
something that you have to find a customised solution for based on the
specifics of your program: I can't see any efficient way to support
drawing while a cursor is being displayed (other than using hardware
cursors, and that's specific to a few accelerated graphics chipsets).


--
Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
Beauty is a French phonetic corruption of a short cloth neck ornament.

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