From:	"Get'Fix" <mnemonic AT discover DOT co DOT za>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Speed difference DOS / Win95 ???
Date:	Mon, 12 Oct 1998 20:43:04 +0200
Organization:	The South African Internet Exchange
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

Yebo,

Could someone please explain why I get the following results?

I have a voxel landscape test program that "flies" over a voxel lanscape
accessing the linear frame buffer directly but here's the catch... when I
boot DOS only, I get 40 fps on my PII 300A & AGP system and when I run it
from a DOS prompt in Win95, I get 70 fps ?!?!?!?!?!?!

Why the faster performance running from within Win95?
I don't use any libraries eg Allegro or accelerator functions and yes!!! it
is faster physically as I see it on the screen so it is no problem with the
timers or fps calculation...

Drawing it on 320x200, 64k colour, lfb (VESA2) using RAM as a double buffer
then copy it to the screen 32 bits at a time  (rep movsd). PII 300A with a
AGP card & 32Mb system RAM. I use lookup for colour indexing and 1024x1024
colour and height maps.

If possible, how can I get it in DOS only to also run at 70 fps?

Thanks,
gfx.

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