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From: a976@mindlink.UUCP (Ron Tarrant)
Newsgroups: comp.graphics
Subject: 3D problem
Message-ID: <3510@mindlink.UUCP>
Date: 12 Oct 90 03:00:12 GMT
Organization: MIND LINK! - British Columbia, Canada
Lines: 27

I'm having a little difficulty wrapping my brain around this
particular problem. I'm hoping someone can stear me in the right
direction.

Problem:        calculate a 3D vector normal ("up" direction) given two
                3D coordinates and a tilt angle in degrees
                (0 = straight up)


Doing this in 2D is easy:

        convert degrees to radians:

                        radians = (degrees * pi) / 180

        then:

                        x = radius * cos(radians)
                        y = radius * sin(radians)


But adding the third dimension is a bit beyond my understanding
at this point. Does anyone know how I might do this?
-Ron Tarrant
a976@Mindlink.UUCP

Please either post here or e-mail directly to me if you prefer.