PolytopeIntersector returns no hits when zoomed in (3.6.5)

[AndrewC]

Hi,

I am using the PolytopeIntersector to select objects in a "selection box"

Works as expected in most cases.

However when I am "zoomed in" (perspective view) fairly tightly ( the eye point is inside the bounding box of the geometry), the PolytopeIntersector returns "no hits" on the geometry.

I am at my wits end on this one after walking through the OSG code, it seems to be deciding the geometry is not inside the planes of the Polytope.

Andrew

[AndrewC]

To answer my own question. The approach that worked was to just remove the "zNear" plane from the Polytope. It is the last plane.

Seems like an unnecessary hack.

    PolytopeIntersector* picker
      = new PolytopeIntersector ( osgUtil::Intersector::PROJECTION, nx1, ny1, nx2, ny2 );

    auto planeList = picker->getPolytope().getPlaneList();
    planeList.pop_back();
    picker->getPolytope().set ( planeList );