Subject: [amos-list] Re: Crossing lines, fast.
From: Ashley Clarke <[email-masked]>
To: Andrew Crowe <[email-masked]>
Date: Tue, 04 May 1999 20:51:27 -0000

From: Ashley Clarke <[email-masked]>

On 04-May-99, Andrew Crowe wrote:
>From: Andrew Crowe <[email-masked]>

>Hi Everybody,

>   I know this was asked a while ago, and I know /I/ answered it, but has
>anyone got a good routine to check if two lines are crossing? Speed *is*
>important, so it can't check it graphically, it /has/ to be mathamatical.

>   And also, does anyone know a way to check if a point is in a closed
>polygon of any shape? (you know, like the lasso tool in dpaint)

>See ya.
>-- 
>       Manta Soft  -  Amiga programing & web page designing
>   Http://members.tripod.com/~mantasoft/      ICQ: 21829166
>     Homepage updated 29/4/99 --- Bomberman clone major update
>  - ------------------- Quote of the day: -------------------- -
>I like work ... I can sit and watch it for hours.

-- 

I don't have any routines, but I think you'll find the answers (with examples)
in any
3D Graphics Computer Book. The Crossing Lines Algorythm would be under the
subject
of Vectors (for Ray Tracing) and enclosed points should be dealt with under
the 
subjects of Hidden Line removal or Plane definers.

Ashley Clarke <[email-masked]>

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