Oh, Okay.
Sorry, didnt look it up enough before answering.
Problems with transforms was exactly what i thought would be a problem.

But, thank you! I will look in to polytypes more.



On 6/26/06, Robert Osfield <[EMAIL PROTECTED]> wrote:
A polytope tells you wants inside or outside or bisecting.  A
BoundingBox is not a good choice to test against as it can get sheared
by transforms in the scene graph, while a polytope can handle this
just fine, so convert the bounding box into a polytope then do the
testing.

On 6/26/06, David Johansson <[EMAIL PROTECTED]> wrote:
> Hi Robert, thanks for the reply!
>
> Well, its kindof what i want. As of now im working with picking
> objects in the scenegraph. But eventually i want to be able to select
> objects inside of an boundingbox.
> Eg. user draws a box with the mouse, and selects all the objects inside it.
>
> I found a example of this at:
> http://www.openscenegraph.org/osgwiki/pmwiki.php/Tasks/OsgIntersect
> This is pretty much what i want to be done, find nodes/drawables
> inside a boundingbox.
> But, from what i can understand this code is nolonger developed or
> maintained. And i didn't manage to get the examples running.
>
> If i understand correctly the Polytope suggestion you gave me would
> only give me objects that are intersected. Wich means i wouldn't get
> objects inside it(?).
>
> Since there are functions like:
>         /** Return true if this bounding box intersects the specified
> bounding box. */
>         bool intersects(const BoundingBox& bb) const
>         /** Returns true if this bounding box contains the specified
> coordinate. */
>         inline bool contains(const Vec3& v) const
>
> On the boundingbox it shouldn't be to hard to check if any objects
> boundingbox is inside the "selected" boundingbox.
>
> I figured that there was a way to do this in a similar way as the
> Linesegment & intersectVisitor does.
>
> MVH
> David Johansson
>
>
>
> On 6/26/06, Robert Osfield <[EMAIL PROTECTED]> wrote:
> > Hi David,
> >
> > Not quite sure what you are after, is that you want to use a polytope
> > to intersect with a scene, rather than a line segmenet as
> > IntersectVisitor does?
> >
> > There is a spealized code in src/osgSim/SphereSegmenet.cpp does create
> > a osg::Polytope
> > and traversing throught the scene picking out what elements intersect
> > it.  Perhaps this would be useful guide for you.
> >
> > BTW, a Polytope can be used to represent a bounding box, by building
> > it from 6 half space planes.
> >
> >
> > Robert.
> >
> > On 6/25/06, David Johansson <[EMAIL PROTECTED]> wrote:
> > > Hi All!
> > >
> > > I have been looking for a while now, but have not found, a way to use
> > > a BoundingBox and a IntersectVisitor.
> > >
> > > I'm not sure if it's currently implemeted, but instead of writing my
> > > own functions i thought i might just ask.
> > > As shown in some examples you can use a LineSegment and a
> > > IntersectVisitor to find node's (geodes) that intersect with a given
> > > line. Since i am using this to Select objects (sometimes very thin
> > > lines) with a mouse this does pose a problem. As you need to click on
> > > the exact pixel to select the object.
> > > So, i was thinking that maybe you could use a BoundingBox instead, and
> > > check if any object is inside. So, back to the question.. Is there a
> > > way to do this allready implemeted into OSG?
> > >
> > > Thanks in advance!
> > >
> > > MVH
> > > David Johansson
> > > _______________________________________________
> > > osg-users mailing list
> > > [email protected]
> > > http://openscenegraph.net/mailman/listinfo/osg-users
> > > http://www.openscenegraph.org/
> > >
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> >
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