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// $Id: G4CurveRayIntersection.icc,v 1.4 2006/06/29 18:39:07 gunter Exp $
// GEANT4 tag $Name: geant4-09-02-ref-02 $
//
// --------------------------------------------------------------------
// GEANT 4 inline definitions file
//
// G4CurveRayIntersection.icc
//
// Implementation of inline methods of G4CurveRayIntersection
// --------------------------------------------------------------------

inline
void G4CurveRayIntersection::Init(G4Curve& c0, const G4Ray& r0)
{
  c= &c0;
  r= &r0;
  d= kInfinity;
  notComputed= allFlags;
}

//////////////////////////////////////////////////////////////////////////////

inline
const G4Ray& G4CurveRayIntersection::GetRay() const
{
  return *r;
}

//////////////////////////////////////////////////////////////////////////////

inline
void G4CurveRayIntersection::Reset()
{
  d= +kInfinity;
  notComputed= uFlag|pFlag;
}

inline void
G4CurveRayIntersection::ResetPPoint(G4double u0)
{
  d= 0;
  u= u0;
  notComputed= pFlag|dFlag;
}

inline void
G4CurveRayIntersection::Reset(const G4Point3D& p0)
{
  d= 0;
  p= p0;
  notComputed= uFlag|dFlag;
}

inline
void G4CurveRayIntersection::Reset(G4double u0, const G4Point3D& p0)
{
  d= 0;
  u= u0;
  p= p0;
  notComputed= dFlag;
}

inline void
G4CurveRayIntersection::ResetDistance(G4double d0)
{
  d= d0;
  notComputed= uFlag|pFlag;
}

inline
void G4CurveRayIntersection::Reset(G4double u0, G4double d0)
{
  d= d0;
  u= u0;
  notComputed= pFlag;
}

inline
void G4CurveRayIntersection::Reset(const G4Point3D& p0, G4double d0)
{
  d= d0;
  p= p0;
  notComputed= uFlag;
}

inline
void G4CurveRayIntersection::Reset(G4double u0, const G4Point3D& p0,
                                   G4double d0)
{
  d= d0;
  u= u0;
  p= p0;
  notComputed= 0;
}

//////////////////////////////////////////////////////////////////////////////

inline
G4double G4CurveRayIntersection::GetPPoint()
{
  if (notComputed & uFlag) {
    if (notComputed & pFlag) {
      p= r->GetPoint(d);
      notComputed &= ~pFlag;
    }
    u= c->GetPPoint(p);
    notComputed &= ~uFlag;
  }
  return u;
}

inline
const G4Point3D& G4CurveRayIntersection::GetPoint()
{
  if (notComputed & pFlag) {
    if (notComputed & dFlag) {
      p= c->GetPoint(u);
    } else {
      p= r->GetPoint(d);
    }
    notComputed &= ~pFlag;
  }
  return p;
}

inline
G4double G4CurveRayIntersection::GetDistance()
{
  if (notComputed & dFlag) {
    if (notComputed & pFlag) {
      p= c->GetPoint(u);
      notComputed &= ~pFlag;
    }
    d= r->GetPPoint(p);
    notComputed &= ~dFlag;
  }
  return d;
}

//////////////////////////////////////////////////////////////////////////////

inline
void G4CurveRayIntersection::UpdateWithPointOnCurve(G4CurveRayIntersection& is)
{
  if (d!=kInfinity) {
    // not the first intersection
    G4double dTmp= is.GetDistance();
    if (dTmp < kCarTolerance || GetDistance() <= dTmp) {
      // not on ray or not the closest intersection
      return;
    }
  }
  // accepted
  *this= is;
}	

inline
void G4CurveRayIntersection::Update(G4CurveRayIntersection& is)
{
  if (c->IsBounded()) {
    if (!c->IsPOn(is.GetPPoint())) {
      return;
    }	
  }
  UpdateWithPointOnCurve(is);
}