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: X-Newsreader: Forte Agent 1.5/32.452 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 30 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?