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

  Program:   Visualization Toolkit
  Module:    vtkFocalPlanePointPlacer.h

  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 
// .SECTION Description
// 
//
// .SECTION See Also

#ifndef __vtkFocalPlanePointPlacer_h
#define __vtkFocalPlanePointPlacer_h

#include "vtkPointPlacer.h"

class vtkRenderer;

class VTK_WIDGETS_EXPORT vtkFocalPlanePointPlacer : public vtkPointPlacer
{
public:
  // Description:
  // Instantiate this class.
  static vtkFocalPlanePointPlacer *New();

  // Description:
  // Standard methods for instances of this class.
  vtkTypeRevisionMacro(vtkFocalPlanePointPlacer,vtkPointPlacer);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Descirption:
  // Given a renderer and a display position, compute
  // the world position and orientation. The orientation
  // computed by the placer will always line up with the
  // standard coordinate axes. The world position will be
  // computed by projecting the display position onto the
  // focal plane. This method is typically used to place a
  // point for the first time.
  int ComputeWorldPosition( vtkRenderer *ren,
                            double displayPos[2], 
                            double worldPos[3],
                            double worldOrient[9] );
  
  // Description:
  // Given a renderer, a display position, and a reference
  // world position, compute a new world position. The
  // orientation will be the standard coordinate axes, and the
  // computed world position will be created by projecting
  // the display point onto a plane that is parallel to
  // the focal plane and runs through the reference world
  // position. This method is typically used to move existing
  // points.
  int ComputeWorldPosition( vtkRenderer *ren,
                            double displayPos[2], 
                            double refWorldPos[3],
                            double worldPos[3],
                            double worldOrient[9] );
  
  // Description:
  // Validate a world position. All world positions
  // are valid so these methods always return 1.
  int ValidateWorldPosition( double worldPos[3] );
  int ValidateWorldPosition( double worldPos[3],
                             double worldOrient[9]);
  
protected:
  vtkFocalPlanePointPlacer();
  ~vtkFocalPlanePointPlacer();

  void GetCurrentOrientation( double worldOrient[9] );
  
private:
  vtkFocalPlanePointPlacer(const vtkFocalPlanePointPlacer&);  //Not implemented
  void operator=(const vtkFocalPlanePointPlacer&);  //Not implemented
};

#endif
