From:	"Duncan Coutts" <Duncan DOT Coutts AT dial DOT pipex DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Nearptr putpixel method?
Date:	Sat, 11 Sep 1999 17:24:20 +0100
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>No, the nearptr hack is not more convenient. It brings with it general
>protection faults, page faults, and other things that, if you use nearptr,
>are your fault, up to and including data loss.


So what is our considered opinion on the best way to write pixels to the
screen? For example when using A000 or Vesa LFB. I do it by allocating
selectors and using farptr. This method maintains memory protection (one
stray pixel causes an exception) and is still quite effecient. It is true
that it is not so convenient from a notation point of view, as you can't use
normal pointers.

How do most people do this?
What does Allegro do?

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