Path: chuka.playstation.co.uk!news
From: Alex Herbert <aherbert@ndirect.co.uk>
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: GsLinkObject4 Confusion - Moving on to GsSortObject4
Date: Fri, 28 Aug 1998 17:10:11 +0000
Organization: PlayStation Net Yaroze (SCEE)
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James Russell wrote:

> Gerrit Goossen wrote:
> >
> > I guess now my question is: Can anyone tell me exactly what operations
> > GsSortObject4() performs?
> >
> > - Is perspective conversion performed on all the verticies in a TMD
> > object? (Regardless of whether they are used in primitives or not?)
>
> Nope, only the ones that are used will be converted.
>
> > Or does it perform the same conversion on the verticies multiple times if
> > they are used in multiple primitives?
>
> Yes. Not exactly efficient, I know.
>

That's really crap.  I did wonder what was making GsSortObject4() so slow.  So all my
efforts of sharing vertices and (especially) normals was a waste of time 'cos they'll be
recalculated for each polygon anyway.  What dumb idiot came up with this?  I assumed that
all the vertices/normals would be processed first (whether used or not) and the 2D
drawing primitives were then built using this data.  That would have been the
sensible/efficient way to do it.

Talking of dumb idiots, I guess I should have worked that out for myself, as the way I
thought it worked would need workspace to hold the processed vertices/normals - which is
never specified with GsSortObject4().

Ho hum...  I need direct GTE access and the ability to sort 2D primitives, and I need it
NOW!


Herbs