From:	"Damian Yerrick" <die DOT spammers AT pineight DOT 8m DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Nearptr putpixel method?
Date:	Sun, 29 Aug 1999 22:37:53 -0500
Organization:	Rose-Hulman Institute of Technology
Message-ID:	<7qcucs$78c$1@solomon.cs.rose-hulman.edu>
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Legolas tried to putpixel() in mode 13h (its frame buffer is at absolute
address 0x0000a000) using the nearptr hack. After trying to work it out with
Dan Gold, Legolas recompiled a day later and it worked fine.

> ummm... scratch that. Yes, I was in mode 13h, but it didn't work. Now,
> suddenly it does. Speed-wise, there is no improvement over the farptr
method

That's because the Pentium is doing the same work, just in a different
segment selector.

> (or maybe an infinitesimal improvement, but not signifigant). It does,
> however seem to be a more convenient way of accessing the video memory.

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.

> I'll experiment with it over time.

Don't if you value your data.

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