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

  Program:   Visualization Toolkit
  Module:    vtkPointPicker.h
  Language:  C++
  Date:      $Date$
  Version:   $Revision$


Copyright (c) 1993-2000 Ken Martin, Will Schroeder, Bill Lorensen 
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

 * Redistributions of source code must retain the above copyright notice,
   this list of conditions and the following disclaimer.

 * Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

 * Neither name of Ken Martin, Will Schroeder, or Bill Lorensen nor the names
   of any contributors may be used to endorse or promote products derived
   from this software without specific prior written permission.

 * Modified source versions must be plainly marked as such, and must not be
   misrepresented as being the original software.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/
// .NAME vtkPointPicker - select a point by shooting a ray into a graphics window
// .SECTION Description
// vtkPointPicker is used to select a point by shooting a ray into a graphics
// window and intersecting with actor's defining geometry - specifically 
// its points. Beside returning coordinates, actor, and mapper, vtkPointPicker
// returns the id of the closest point within the tolerance along the pick ray.

// .SECTION See Also
// vtkPicker vtkCellPicker.

#ifndef __vtkPointPicker_h
#define __vtkPointPicker_h

#include "vtkPicker.h"

class VTK_EXPORT vtkPointPicker : public vtkPicker
{
public:
  static vtkPointPicker *New();
  vtkTypeMacro(vtkPointPicker,vtkPicker);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Get the id of the picked point. If PointId = -1, nothing was picked.
  vtkGetMacro(PointId,int);

protected:
  vtkPointPicker();
  ~vtkPointPicker() {};
  vtkPointPicker(const vtkPointPicker&) {};
  void operator=(const vtkPointPicker&) {};

  int PointId; //picked point

  float IntersectWithLine(float p1[3], float p2[3], float tol, 
			  vtkActor *assem, vtkActor *a, vtkMapper *m);
  void Initialize();

};

#endif


