Beispiel #1
0
/*! The IntersectAction callback for Geometry. It computes if the ray used in
    the IntersectAction \a action hits this object and if that is the case,
    which triangle is hit.

    \param[in] action IntersectAction performing the intersect test.
    \return Action result code, \see OSG::Action.

    \note This method is registered with the IntersectAction and automatically
    called from there, you probably never have to call it manually.
*/
Action::ResultE Geometry::intersect(Action * action)
{
    IntersectAction      *ia = dynamic_cast<IntersectAction*>(action);
   
    ia->getActNode()->updateVolume();
    const BoxVolume      &bv = ia->getActNode()->getVolume();

    if(bv.isValid() && !bv.intersect(ia->getLine()))
    {
        return Action::Skip; //bv missed -> can not hit children
    }

    TriangleIterator it  = this->beginTriangles();
    TriangleIterator end = this->endTriangles  ();
    Real32           t;
    Vec3f            norm;
    Line             ia_line(ia->getLine());

    for(; it != end; ++it)
    {
        if(ia_line.intersect(it.getPosition(0),
                             it.getPosition(1),
                             it.getPosition(2), t, &norm))
        {
            ia->setHit(t, ia->getActNode(), it.getIndex(), norm, -1);
        }
    }

    // If we need to test lines, iterate over lines and test for
    // lines that are within width distance from the line
    if(ia->getTestLines())
    {       
       Real32 range_sq  = ia->getTestLineWidth();
       range_sq         = range_sq * range_sq;
       LineIterator it  = this->beginLines();
       LineIterator end = this->endLines  ();
       Pnt3f  pt1, pt2;
       OSG::Vec3f  norm;       

       // Find closest points and if they are within the range, then add a hit
       for(; it != end; ++it)
       {          
          Line cur_line(it.getPosition(0), it.getPosition(1));
          ia_line.getClosestPoints(cur_line, pt1, pt2);
          Real32 dist_sq( pt1.dist2(pt2) );

          if (dist_sq <= range_sq)
          {
             t = ia_line.getPosition().dist(pt1);
             ia->setHit(t, ia->getActNode(), -1, norm, it.getIndex());
          }
       }
    }

    return Action::Continue;
}