Ah. The OP didn't specify "axis-aligned" in the initial post (or if it was mentioned, I somehow missed it... Either way) my apologies.
The task appears to be under-specified. You need to answer this question: Do you want something fast and (possibly) inaccurate, or do you want accurate? The fast method would be to compute the eight corners, transform them, and create a new BB that contains the eight transformed points. The accurate way would be to transform all the coordinates that comprise the geometry and build a BB that contains them all. Paul Martz Skew Matrix Software LLC http://www.skew-matrix.com +1 303 859 9466 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jean-Sébastien Guay Sent: Thursday, May 14, 2009 8:13 AM To: OpenSceneGraph Users Subject: Re: [osg-users] World space bounding box Hi Paul, > const osg::MatrixList& m = node->getWorldMatrices(); > osg::ComputeBoundsVisitor cbv; > node->accept( cbv ); > osg::BoundingBox bb = cbv.getBoundingBox(); > osg::Vec3 minV = bb._min * m.front(); > osg::Vec3 maxV = bb._max * m.front(); > osg::notify( osg::ALWAYS ) << minV << std::endl << maxV << > std::endl; This method does not result in an AABB if the matrix contained a rotation. The bounding box is no longer axis-aligned. You need to do as the OP suggested, transform the 8 corners of the box and then rebuild an AABB from those. Though I think the code could be simplified and cleaned up. J-S -- ______________________________________________________ Jean-Sebastien Guay [email protected] http://www.cm-labs.com/ http://whitestar02.webhop.org/ _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
