Gan Wang (gan++at++cavalier.cambridge.com)
Fri, 12 Jul 1996 11:08:03 -0400
PFIS_FALSE:
The intersection of the second box argument and the first box
is empty.
PFIS_MAYBE:
The intersection of the second box argument and the first box
might be non-empty.
PFIS_MAYBE | PFIS_TRUE:
The intersection of the second box argument and the first box
is definitely non-empty.
PFIS_MAYBE | PFIS_TRUE | PFIS_ALL_IN:
The second box argument is non-empty and lies entirely inside
the first box.
with possible exception of pfSphereContains*, which does not return PFIS_FALSE
according to manpage.
Sorry for not making that clear, and thanks for all the comments.
Gan
On Jul 11, 4:04pm, Steve Baker wrote:
> Subject: Re: spheres and boxes
>
> It sounds to me like we are confusing three tests and their results
>
> Sphere-completely-surrounds-box -- Test all eight vertices, if
> they are all contained inside
> the sphere - then so is the box.
>
> surface-of-Sphere-intersects-surface-of-box -- Nasty test - helped out
somewhat
> by the fact that the box is axially
> aligned.
>
> solid-Sphere-intersects-solid-box -- More than just the OR
> of the previous two tests because the
> entire sphere could be totally inside
> the box and hence fail both of the
earlier
> tests - yet still need to pass this one.
>
> Look at the man page for pfBoxContainsBox - it have to return three separate
> flags to describe what happened (and one of those is a 'PFIS_MAYBE')
>
> First define your requirements, then document them - and only then start to
> write code. (Oh yea - right - I do that *all* the time....NOT!)
>
>
> Steve Baker 817-323-1361 (Vox-Lab)
> Hughes Training Inc. 817-695-8776 (Vox-Office/vMail)
> 2200 Arlington Downs Road 817-695-4028 (Fax)
> Arlington, Texas. TX 76005-6171 steve++at++mred.bgm.link.com (eMail)
>
> =======================================================================
> List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/
> Submissions: info-performer++at++sgi.com
> Admin. requests: info-performer-request++at++sgi.com
>-- End of excerpt from Steve Baker
--Gan Wang
Cambridge Research Associates Office: 703-790-0505 ext.7210 1430 Spring Hill Road, Suite 200 Fax: 703-790-0370 McLean, VA 22102 Internet: gan++at++cambridge.com ======================================================================= List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/ Submissions: info-performer++at++sgi.com Admin. requests: info-performer-request++at++sgi.com
This archive was generated by hypermail 2.0b2 on Mon Aug 10 1998 - 17:53:10 PDT