Path: chuka.playstation.co.uk!news
From: kr705@gre.ac.uk (Rad)
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: Line normal
Date: Fri, 18 Feb 2000 12:14:38 GMT
Organization: PlayStation Net Yaroze (SCEE)
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Hi Steven (or anyone else who can help!),

Yeah, I'm refering to a 2D line.

Say I have  line A which is 64 units long and I want to create another
line (B) which is perpendicular (intersecting at 90 degrees) to line A
and is 256 units long 128 units on either side of line A (make any
sense? :-/)

I'll try and draw a diagram:

		*
		*
       line B  ****************
		*
		*
	         line A


How do I calculate line B (the end points)? Isn't line B the normal to
line A or are normals only for 3D polygons?

Why does a 3D line have an infinite number of lines normal to it?

Thanks for any help,
Rad.


On Thu, 17 Feb 2000 17:27:57 GMT, sosman@terratron.com (Steven Osman)
wrote:

>A 3D line in space has an infinite number of lines normal to it.
>
>Are you referring to a 2D line?
>
>Steven
>
>On Thu, 17 Feb 2000 17:11:45 GMT, kr705@gre.ac.uk (Rad) wrote:
>
>>Hi,
>>
>>If I have a line, how do I calculate another line perpendicular to
>>this line?
>>Or should that be how do I calculate the normal to a line?
>>
>>Thanks,
>>Rad.
>