Re: [Algorithms] Collisions with VIPM

[Oscar B. <tr...@te...>]

I'm thinking on terrain and level (map) collision, not in small objects
collision, something I will do with an octree for static and non-static object
(for moving ones I may try another stratregy...). The hardest part is terrain
collision, we can subdivide our terrain in chunks but if they have many polys,
it isn't a good idea to use the current mesh directly. At the moment, I only can
imagine to use a mesh with fewer polys and skip chunks that can be touched using
an octree and portals (these two things can be used to fast visibility skips )
but this can fail in some specific tasks. I ask if there's another way to do
this....

Mark Wayland wrote:

> The OBB tree is used for coarse collision detection - a single OBB may even
> be enough, depending on the shape of your object ... it depends what form of
> collision detection you need - do you need polygon level or just rough OBB ?
>
> Perhaps you could maintain a convex hull generated from the VIPM mesh every
> so often, which may be good enough for your needs ?  I believe Stan Melax
> has done some work on dynamic reduction of the convex hull too ... check out
> his site (sorry, don't have the link at the mo').
>
> Mark
>
> ----- Original Message -----
> From: "Oscar Blasco" <tr...@te...>
> To: <gda...@li...>
> Sent: Friday, August 04, 2000 9:06 AM
> Subject: Re: [Algorithms] Collisions with VIPM
>
> > Ok, when I said *desired polys* I was thinking on fewer polys, but it can
> > cause object to collide with nothing (aka air...). I'm not sure what you
> > want to say with using OBB's... divide the VIPMesh in subchunks and make a
> > tree of OBB's to quickly skip parts of the model?
> >
> > Charles Bloom wrote:
> >
> > > Or, even better, using a static version of the mesh with *fewer*
> > > polys.  Better still, use a sphere-tree or OBB-tree fit to
> > > the mesh with roughly 100 spheres and/or OBB's.
> > >
> > > At 12:24 AM 8/4/2000 +0200, you wrote:
> > > >Hi,
> > > >
> > > >How can be done fast collision detection with VIPM when it's always
> > > >changing its morphology?, using an static version of the mesh with all
> > > >desired polys?
> > > >
> > > >
> > > >_______________________________________________
> > > >GDAlgorithms-list mailing list
> > > >GDA...@li...
> > > >http://lists.sourceforge.net/mailman/listinfo/gdalgorithms-list
> > > >
> > > >
> > > --------------------------------------
> > > Charles Bloom           www.cbloom.com
> > >
> > > _______________________________________________
> > > GDAlgorithms-list mailing list
> > > GDA...@li...
> > > http://lists.sourceforge.net/mailman/listinfo/gdalgorithms-list
> >
> >
> > _______________________________________________
> > GDAlgorithms-list mailing list
> > GDA...@li...
> > http://lists.sourceforge.net/mailman/listinfo/gdalgorithms-list
>
> _______________________________________________
> GDAlgorithms-list mailing list
> GDA...@li...
> http://lists.sourceforge.net/mailman/listinfo/gdalgorithms-list