// This code implementation is the intellectual property of
// the GEANT4 collaboration.
//
// By copying, distributing or modifying the Program (or any work
// based on the Program) you indicate your acceptance of this statement,
// and all its terms.
//
// $Id: G4PolyconeSide.hh,v 1.3 2000/11/02 16:54:49 gcosmo Exp $
// GEANT4 tag $Name: geant4-03-00 $
//
// 
// --------------------------------------------------------------------
// GEANT 4 class header file
//
//
// G4PolyconeSide
//
// Class description:
//
//   Class implmenting a face that represents one conical side
//   of a polycone:
//
//   G4PolyconeSide( const G4PolyconeSideRZ *prevRZ,
//                   const G4PolyconeSideRZ *tail,
//                   const G4PolyconeSideRZ *head,
//                   const G4PolyconeSideRZ *nextRZ,
//                   G4double phiStart, G4double deltaPhi, 
//                   G4bool phiIsOpen, G4bool isAllBehind=false )
//
//   Values for r1,z1 and r2,z2 should be specified in clockwise
//   order in (r,z).

// Author: 
//   David C. Williams (davidw@scipp.ucsc.edu)
// --------------------------------------------------------------------

#ifndef G4PolyconeSide_hh
#define G4PolyconeSide_hh

#include "G4VCSGface.hh"

class G4IntersectingCone;

typedef struct {
        G4double r, z;  // start of vector
} G4PolyconeSideRZ;
 
class G4PolyconeSide : public G4VCSGface
{
  public:

	G4PolyconeSide( const G4PolyconeSideRZ *prevRZ,
                        const G4PolyconeSideRZ *tail,
                        const G4PolyconeSideRZ *head,
                        const G4PolyconeSideRZ *nextRZ,
			G4double phiStart, G4double deltaPhi, 
			G4bool phiIsOpen, G4bool isAllBehind=false );
	virtual ~G4PolyconeSide();
	
	G4PolyconeSide( const G4PolyconeSide &source );
	G4PolyconeSide& operator=( const G4PolyconeSide &source );
	
	G4bool Intersect( const G4ThreeVector &p, const G4ThreeVector &v,	
			  G4bool outgoing, G4double surfTolerance,
			  G4double &distance, G4double &distFromSurface,
			  G4ThreeVector &normal, G4bool &isAllBehind );

        G4double Distance( const G4ThreeVector &p, G4bool outgoing );
	
	EInside Inside( const G4ThreeVector &p, G4double tolerance, 
			G4double *bestDistance );
	
	G4ThreeVector Normal( const G4ThreeVector &p,  G4double *bestDistance );

	G4double Extent( const G4ThreeVector axis );

	void CalculateExtent( const EAxis axis, 
			      const G4VoxelLimits &voxelLimit,
			      const G4AffineTransform &tranform,
			      G4SolidExtentList &extentList       );

	G4VCSGface *Clone() { return new G4PolyconeSide( *this ); }
	
  protected:

	G4double r[2], z[2];	// r, z parameters, in specified order
	G4double startPhi,	// Start phi (0 to 2pi), if phiIsOpen
		 deltaPhi;	// Delta phi (0 to 2pi), if phiIsOpen
	G4bool	 phiIsOpen;	// True if there is a phi slice
	G4bool	 allBehind;	// True if the entire solid is "behind" this face
	
	G4IntersectingCone *cone;	// Our intersecting utility class
	
	G4double rNorm, zNorm;	// Normal to surface in r,z space
	G4double rS, zS;	// Unit vector along surface in r,z space
	G4double length;	// Length of face in r,z space
	G4double prevRS,
		 prevZS;	// Unit vector along previous polyconeSide
	G4double nextRS,
		 nextZS;	// Unit vector along next polyconeSide
	
	G4double rNormEdge[2],
		 zNormEdge[2];	// Normal to edges

	G4ThreeVector *corners;	// The coordinates of the corners (if phiIsOpen)
				
	G4double DistanceAway( const G4ThreeVector &p, G4bool opposite,
			       G4double &distOutside2, G4double *rzNorm=0 );
			
	G4bool PointOnCone( const G4ThreeVector &hit, G4double normSign,
			    const G4ThreeVector &p, const G4ThreeVector &v, G4ThreeVector &normal );

	void CopyStuff( const G4PolyconeSide &source );
	
	static void FindLineIntersect( G4double x1, G4double y1,
				       G4double tx1, G4double ty1,
				       G4double x2, G4double y2,
				       G4double tx2, G4double ty2,
				       G4double &x, G4double &y );
};


#endif