/*=========================================================================

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkVolumePicker.h,v $

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// .NAME vtkVolumePicker - ray-cast picker enhanced for volumes
// .SECTION Description
// vtkVolumePicker is a subclass of vtkCellPicker.  It has one
// advantage over vtkCellPicker for volumes: it will be able to
// correctly perform picking when CroppingPlanes are present.  This
// isn't possible for vtkCellPicker since it doesn't link to
// the VolumeRendering classes and hence cannot access information
// about the CroppingPlanes.
//
// .SECTION See Also
// vtkPicker vtkPointPicker vtkCellPicker
//
// .SECTION Thanks
// This class was contributed to VTK by David Gobbi on behalf of Atamai Inc.

#ifndef __vtkVolumePicker_h
#define __vtkVolumePicker_h

#include "vtkCellPicker.h"

class VTK_VOLUMERENDERING_EXPORT vtkVolumePicker : public vtkCellPicker
{
public:
  static vtkVolumePicker *New();
  vtkTypeRevisionMacro(vtkVolumePicker, vtkCellPicker);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Set whether to pick the cropping planes of props that have them.
  // If this is set, then the pick will be done on the cropping planes
  // rather than on the data. The GetCroppingPlaneId() method will return
  // the index of the cropping plane of the volume that was picked.  This
  // setting is only relevant to the picking of volumes.
  vtkSetMacro(PickCroppingPlanes, int);
  vtkBooleanMacro(PickCroppingPlanes, int);
  vtkGetMacro(PickCroppingPlanes, int);

  // Description:
  // Get the index of the cropping plane that the pick ray passed
  // through on its way to the prop. This will be set regardless
  // of whether PickCroppingPlanes is on.  The crop planes are ordered
  // as follows: xmin, xmax, ymin, ymax, zmin, zmax.  If the volume is
  // not cropped, the value will bet set to -1.
  vtkGetMacro(CroppingPlaneId, int);

protected:
  vtkVolumePicker();
  ~vtkVolumePicker();

  virtual void ResetPickInfo();

  virtual double IntersectVolumeWithLine(const double p1[3],
                                         const double p2[3],
                                         double t1, double t2,
                                         vtkProp3D *prop, 
                                         vtkAbstractVolumeMapper *mapper);

  static int ClipLineWithCroppingRegion(const double bounds[6],
                                        const int extent[6], int flags,
                                        const double x1[3], const double x2[3],
                                        double t1, double t2,
                                        int &extentPlaneId, int &numSegments,
                                        double *t1List, double *t2List,
                                        double *s1List, int *planeIdList);

  int PickCroppingPlanes;
  int CroppingPlaneId;

private:
  vtkVolumePicker(const vtkVolumePicker&);  // Not implemented.
  void operator=(const vtkVolumePicker&);  // Not implemented.
};

#endif