Re: List of entity classnames

David Etherton (
Mon, 25 Mar 1996 15:19:53 -0800 (PST)

From: (David Etherton)
Message-Id: <9603252319.AA17245@fuzz.megatek>
Subject: Re: List of entity classnames
Date: Mon, 25 Mar 1996 15:19:53 -0800 (PST)
In-Reply-To: <> from "Stephen Crowley" at Mar 25, 96 05:01:03 pm

> BTW, I'm having a little trouble understanding how to figure the =
> distance between (0,0,0) and a plane. If anyone could enlighten me on =
> this subject I be really grateful.

The plane equation is

Ax + By + Cz + D = 0

where (x,y,z) is any point in 3-space, (A,B,C) is the unit normal
(ie the vector perpendicular to the plane), and D is the distance
in 3-space to the plane.

Therefore, D is the value you desire.

If you want the distance between two points, it's just

sqrt(dx*dx + dy*dy + dz*dz) where (dx,dy,dz) is the vector difference
of the two points.

Hope this helps,


David Etherton | Megatek Corporation | "Shop as usual, and avoid panic buying."