Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: mperdue@hrtc.net (Mario Perdue)
Newsgroups: scea.yaroze.programming.3d_graphics
Subject: Re: Wireframe stuff
Date: Thu, 31 Jul 1997 05:35:29 GMT
Organization: SCEA Net Yaroze News
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On Wed, 30 Jul 1997 18:39:02 +0000, Manny Najera
<mnajera@ix.netcom.com> wrote:

>I want to make a cube out of GsGLINEs.  Right now, I have all eight
>points of the cube represented by vectors.  Each frame, I translate each
>of the vectors according to the camera angle, so the cube moves like
>it's supposed to.  I don't remember how to convert the xyz coordinates
>to xy ones, and I need to do this so I can draw lines between the
>points.  Can anyone tell me how this is done?

Manny,

I assume that you want to do a perspective projection. You can use the
following:

x_screen = d * x/z;
y_screen = d * y/z;

where:

x_screen, y_screen    is the screen location
x, y, z               is the 3D location
d                     is the viewing distance from the screen

Mario