From:	"Thomas Harte" <T DOT Harte AT btinternet DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: graphics
Date:	28 Dec 1996 22:39:43 GMT
Organization:	Dell Computer Corporation
Lines:	19
Message-ID:	<01bbf50f$5ce75680$d42649c2@default>
References:	<1 DOT 5 DOT 4 DOT 16 DOT 19961218230509 DOT 19f7ab66 AT mail DOT algonet DOT se> <32c3e184 DOT 1226804 AT news DOT eunet DOT fi>
NNTP-Posting-Host:	host-73-38-212.btinternet.com
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Aleksi Kallio <aleksi AT kalliot DOT pp DOT fi> wrote in article
<32c3e184 DOT 1226804 AT news DOT eunet DOT fi>...
[cut]

> Then draw pixels in this way:
> #include<go32.h>
> #include<sys/farptr.h>
> _farpokeb(_dos_ds, 0xA0000+y*320+x, color);

	Instead of multiplying by 320, I suggest you use two bit-shifts, therefore
changing the line to :-

	_farpokeb(_dos_ds, 0xA0000 + (y << 8) + (y << 6) + x, colour);

	. . . .as this is faster.

		-Thomas

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