Path: chuka.playstation.co.uk!news From: sceetech Newsgroups: scee.yaroze.programming.3d_graphics Subject: Re: New gte functions Date: Mon, 07 Apr 1997 17:46:36 +0100 Organization: SCEE Lines: 79 Message-ID: <334924EB.D5A@interactive.sony.com> References: <3347dd19.3248416@news.playstation.co.uk> <3348D38C.1DC1@interactive.sony.com> <33491dc7.20472943@news.playstation.co.uk> Reply-To: ps_yaroze@interactive.sony.com NNTP-Posting-Host: 194.203.13.10 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Mailer: Mozilla 3.01 (Win95; I) Alex Amsel wrote: > > On Mon, 07 Apr 1997 11:59:24 +0100, sceetech > did quoth at me: > > >around matrix's own axes. When these two (especially the > >latter) are sorted, almost everything becomes clear; > >when a matrix is updated only by translations and by > >rotating about its own axes, it has two vital properties: > >the rows express its axes as vectors in the world coordinate > >system, the columns express the world's axes as vectors > >in the matrix's coordinate system. > > The last bit was interesting - I never knew that. > > But it was all still it besides the point - basically you are saying > to use the gs functions. While these look pretty useful for > prototyping etc., doing my own 3d engine is going to be far better > for most purposes. But it doesn't look like I have the gte functions > to allow me to do rotate/pers/lighting other then by doing everything > as TMD and following strict gs calls. > > e.g. I need to do a fast landscape routine. I don't need some of the > gs stuff while other things I could probably do some tricks with not > possible in gs. On top of this I need the standard object stuff - this > stuff gs could handle. Creating tmd pobjects in realtime and following > gs calls is going to be quite a bit slower than doing the necessary > myself. > > I think a lot of people would like to do their own full 3d engines and > there is no opportunity to do that, quite apart from the lack of > primitive structures. I think you are missing out on a lot of possible > 'skills' this way. I know I could scrape by with gs for a while, but > many better technical programmers could doubtless do some wonderful > Yaroze code given the opportunity. At the moment we all feel like we > have one hand tied behind our back. > > BTW: I would like to be able to release 1-2 bits of source for people, > but I access primitives in the OT directly with macros (i.e. very > similar to the full dev kit). What is Sony's policy on this? I am > happy not to place any info on the net but could I at least out > linkable libs on the net that access primitives (no source) ? > > * Alex Amsel * Into Beyond Web Design & JAVA Programming * > * http://www.intobeyond.com * WWFC Play off ****ers'97 * > MM: "Hand the opposition the lead, the supporters love it" I honestly think you overestimate the speed of GTE versus GS. Most of GS is written in assembler and/or inline GTE macros. The speed difference is really very small, while the difference in development time is large; if two twins did the same game, the one using GTE might get a game engine of 5 or 10% faster, but the other's game would be far more polished in graphics and gameplay. Furthermore, you CAN access objects as polygons rather than tmds using Gs, and doing so is very quick (see the 'clone' sample). You mention some tricks not possible in Gs: I honestly cannot think of anything you can do in GTE that you couldn't do (and in very comparable time) in Gs. If you have anything specific in mind, let me know. You say that lots of people would like to do their own 3d engines and there is no opportunity to do that: I'd like to know what you mean by this. I consider Gs to provide the _basis_ for a 3d engine while leaving much of it very open (eg how to do collision detection and handling, to use 3d models or 3d sprites, etc etc). Please give an indication of precisely what you would like to see done / would like to see possible that isn't there now. Not yet sure of Sony policy on primitive access via linkable libraries, will found out and let you know. Hope to hear from you soon Lewis