Path: chuka.playstation.co.uk!scea!peter_alau@playstation.sony.com From: Joshua Meeds Newsgroups: scee.yaroze.programming.3d_graphics Subject: Re: Problem with positioning Date: Fri, 22 May 1998 07:37:37 -0700 Organization: SCEA News Server Lines: 50 Message-ID: <35658DB1.CC1008BC@sinclair.net> References: <35635f20.1525506@news.playstation.co.uk> NNTP-Posting-Host: dreamer.sincom.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Mailer: Mozilla 4.05 [en] (Win95; I) Actually, +X is to the right, as shown below: -Y +Z | / -X ___|/___ +X | /| -Z / +Y It's the Y axis that keeps getting me; I keep forgetting that -Y=up, so if I want my camera overlooking things, it should be at -200, not at 200. Richard Cutting wrote: > > On 20 May 1998 18:08:54 GMT, jmhannan@cix.co.uk (Jeff Hannan) wrote: > > >I have since waded through the entries in this newsgroup > >and I have become enlightened about many things. > > > >However, I don't recall any discussion of the axes - I > >know that the PSX is -Z-Y, but the direction of the X > >axis is important and it seems to me that the positive X > >direction is to the left > > -Y -Z > > | / > > +X ___|/___ -X > > | > > /| > > +Z / +Y > > > >Am I right? Its yet another thing to be wary of. > > > >Jeff Hannan > > > >P.S. This is great, a thread all to myself. > > Does anyone know why they went this route ? The usual scheme of things > ( and the one used in all the graphics textbooks that I've seen ) is; > > | +y > | > -x ------+----- +x > | > | -y > > This is really annoying me as it means if I want to use any algorithms > in the books I have to bugger about and actually think instead of > being able to copy them straight...... >