Added Intersector::get/setEpsilon(double) to allow users to control what epsilon is used by the LineSegmentIntersector when doing testing of itersections with bounding boxes

This commit is contained in:
Robert Osfield 2013-07-31 13:11:49 +00:00
parent 9c9939e5d4
commit 364e2765e7
2 changed files with 21 additions and 14 deletions

View File

@ -84,11 +84,18 @@ class Intersector : public osg::Referenced
inline bool reachedLimit() { return _intersectionLimit == LIMIT_ONE && containsIntersections(); }
protected:
/** Set Epsilon value, where supported is used in numerical comparisons to workaround number precisions issues.*/
inline void setEpsilon(double epsilon) { _epsilon = epsilon; }
CoordinateFrame _coordinateFrame;
/** Get Epsilon value.*/
inline double getEpsilon() const { return _epsilon; }
protected:
CoordinateFrame _coordinateFrame;
IntersectionLimit _intersectionLimit;
unsigned int _disabledCount;
unsigned int _disabledCount;
double _epsilon;
};

View File

@ -244,6 +244,7 @@ Intersector* LineSegmentIntersector::clone(osgUtil::IntersectionVisitor& iv)
osg::ref_ptr<LineSegmentIntersector> lsi = new LineSegmentIntersector(_start, _end);
lsi->_parent = this;
lsi->_intersectionLimit = this->_intersectionLimit;
lsi->_epsilon = this->_epsilon;
return lsi.release();
}
@ -278,6 +279,7 @@ Intersector* LineSegmentIntersector::clone(osgUtil::IntersectionVisitor& iv)
osg::ref_ptr<LineSegmentIntersector> lsi = new LineSegmentIntersector(_start * inverse, _end * inverse);
lsi->_parent = this;
lsi->_intersectionLimit = this->_intersectionLimit;
lsi->_epsilon = this->_epsilon;
return lsi.release();
}
@ -484,15 +486,13 @@ bool LineSegmentIntersector::intersectAndClip(osg::Vec3d& s, osg::Vec3d& e,const
osg::Vec3d bb_min(bbInput._min);
osg::Vec3d bb_max(bbInput._max);
#if 1
double epsilon = 1e-4;
bb_min.x() -= epsilon;
bb_min.y() -= epsilon;
bb_min.z() -= epsilon;
bb_max.x() += epsilon;
bb_max.y() += epsilon;
bb_max.z() += epsilon;
#endif
// expand the extents of the bounding box by the epsilon to prevent numerical errors resulting in misses.
bb_min.x() -= _epsilon;
bb_min.y() -= _epsilon;
bb_min.z() -= _epsilon;
bb_max.x() += _epsilon;
bb_max.y() += _epsilon;
bb_max.z() += _epsilon;
// compate s and e against the xMin to xMax range of bb.
if (s.x()<=e.x())