From:	Robin Burrows <rburrows AT hotmail DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Code speed-up
Date:	Wed, 28 Jan 1998 16:40:50 +0000
Organization:	Virgin Net Usenet Service
Lines:	16
Message-ID:	<34CF5F92.126C@hotmail.com>
Reply-To:	rburrows AT hotmail DOT com
NNTP-Posting-Host:	194.168.73.210
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Hello,
  Anyone suggest a speed up for this little bit of code:

	for (l=0;l<mapblockheight;l++) {
		maplinecpypt = (unsigned char *) mapdestpt->line[(l+j)] + i;
		for (k=0;k<mapblockwidth;k++) {
			*maplinecpypt = *mapgfxpt; maplinecpypt++; mapgfxpt++;
		}
	}

It seems quite inefficient copying a byte over a 32bit bus, but I'm not
sure how odd addresses would affect a bigger move. The inner line of
this function is called 256*180 times for ONE screen update.

Regards,
Robin Burrows.

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