Path: chuka.playstation.co.uk!news
From: "Steve Dunn" <steve@backroom.tm>
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: 3D Object Size (Vertices section of PLY file)
Date: Mon, 30 Mar 1998 08:08:22 +0100
Organization: PlayStation Net Yaroze (SCEE)
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Think I've got it sussed,
    To make a 'bounding collision box',
I've decided the best course of action
to get the object 'size' is
to poke around and come up with an x,y,z
size from the Vertices section of the
ply file associated with the particular
RSD file.
Though documentation sais the 'vertices'
section contains the X,Y,Z co-ords of
the vertices, one line for each vertex.
I have found that this is in fact
incorrect.
The format I've stumbled across is.. X,
Z, Y.
Try it for yourself.  Create a
200x200x50 cube,convert it,  and look at
the vertices in the ply file.  It is
definitely X,Z,Y.

Anyway, more to point, is there a way to
get these dimensions from the resulting
.tmd file ?

Additionally, I should point out that
this is all in aid of collision
detection.  If anyone can  turn me
around and kick me in the direction of a
nice sample with collision detection I'd
be very happy indeed.

Any help appreciated.

Steve

>I'll kick off in my normal fashion...
>    "I'm probably missing something
>obvious..."
>
>If I slap a 3D object at 0,0,0, is
there
>anywhere in the myriad of structures
>that I could politely question as to
how
>'large' the object is ?  This is for
>collision detection.  I thought I'd be
>quite good at this subject, as I ride a
>motorbike through central London
>everyday !
>
>Also....
>
>    I have a simple cube object (simple
>for you lot, still took me an hour!)
>created in 3DS.  When I export to dxf,
>the normals are all AAF (pointing the
>wrong way), so I can only dab on the
>texture on the 'inside' of the cube.  I
>got around this by using the 'double
>sided polygon' command line wotsit in
>the dxf2rsd tool.  The real problem is
>that all surfaces of the cube are made
>up of 2 triangles.  Now when these are
>displayed, I can see the 'gap' between
>the two triangles on the textured face.
>
>Any help gratefully received...
>
>
>Steve (come back the 6502) Dunn.
>
>