[osg-users] bounding box issue

Gianluca Natale gianluca.natale at adstorino.it
Wed Sep 24 06:52:03 PDT 2008


Hi All.
I have this very strange issue related to bounding boxes.

I derived a class MyDrawable, from osg::Drawable.

And I'm trying to make some experiments with it.

 

I have a model containing two objects:

- a cylinder, made by a bunch of points, defined as an instance of
MyDrawable;

- an object made by just one vertex, defined as an instance of MyDrawable.

 

When I try to draw the model, just the cylinder is shown.

I implemented the method GetBoundingBox()in MyDrawable.

So, obviously, it returns a void BB for the second drawable.

Does it depend on the void BB?
I mean, does OSG check the dimension of the BB of an object before
drawing it, and discard the object if its BB, in screen coords, becomes less
than
some threshold (expressed in pixels)?

 

I suspect this behavior because, if I try to artificially enlarge the BB of
the second drawable,
once I zoom in I can see it on the screen. And disappear when I zoom out
again.

Thank you in advance.
Regards,

Gianluca Natale

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openscenegraph.org/pipermail/osg-users-openscenegraph.org/attachments/20080924/4b4d6c93/attachment-0002.htm>


More information about the osg-users mailing list