From:	phyphor AT takethisoutifyouwannareplyusa DOT net (Louis Brown)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Inevitebly slow writes in VESA?
Organization:	YEA, DREAM ON! Inc.
Message-ID:	<361fc103.1256965@208.25.48.5>
References:	<ranla DOT 11 DOT 0004F5B6 AT post DOT tau DOT ac DOT il>
X-Newsreader:	Forte Agent 1.5/32.452
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Date:	Sat, 10 Oct 1998 19:54:09 GMT
NNTP-Posting-Host:	209.142.12.156
NNTP-Posting-Date:	Sat, 10 Oct 1998 12:54:09 PDT
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp
Reply-To:	djgpp AT delorie DOT com

On Sat, 10 Oct 1998 01:56:09 LOCAL, ranla AT post DOT tau DOT ac DOT il (Tal Lavi)
wrote:

>My ray-caster needs only to draw vertical lines in a 16bpp mode. This, 
>ofcourse, makes it hard to write a dword in a time.
>
>I have succeeded in rewriting the engine so that he'll calculate two 
>vertical scan-lines at once, so they could be drawn on the screen at 
>once(I have not calculated each one dependendly, stored them, at then 
>drawed them, but actually calculated both simultaniusly).
>
>I am calculating every two CONSECUTIVE veritical scan-lines at once(0&1, 2&3,
>etc..), which means that every dword that is written in dword-alligned to the
>beginning of the LFB.
>
>To my disapointment, I haven't gained ALLOT more speed, rather than just 
>some.
>
>Does anyone has a clue about what could have gone wrong? according to my 
>calculations, I should have gained X8 speed.
>My guess(which is very improbable), is that the beginning of the LFB is 
>not DWord alligned. Can this be true?
>
>Please, don't tell me to post my code, it's much too complicated, and it 
>won't do any good.
>
>		Virge		ranla AT post DOT tau DOT ac DOT il

Then how are we supposed to help you if we can't see what the problem
is?

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