From: Marcin Romaszewicz (marcin++at++asmodean.engr.sgi.com)
Date: 02/15/2001 11:59:43
You could create a pfBox (or pfSphere, pfPolytope) and query it as to
whether it contains particular points. Just test the vertices of your
polygons one by one to see if the polygon is contained within the
bounding region. If your polygons are complex, as a first approximation
intersect the bounding box of the polygon against the bounding region. All
this is covered in the pfBox, pfSphere and pfPolytope man pages.
If you're adding and removing polygons within geosets in a multi-processed
program, then you need to use pfFluxes to make your changes MP-safe and
frame synchronous. If you're just modifying the geosets that geodes
contain, that's already MP-safe.
-- Marcin
On Thu, 15 Feb 2001, Tim Woodard wrote:
> Is there a way in performer to query which polygons fall into a given
> bounding box? Given these polygons, I need the ability to add remove
> polygons dynamically. There's mention of this in the performer programmer's
> guide in regard to using flux buffers, but no details are provided. What
> are some possible approaches?
>
> Thanks!
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