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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkIterativeClosestPointTransform.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 vtkIterativeClosestPointTransform - Implementation of the ICP algorithm.
// .SECTION Description
// Match two surfaces using the iterative closest point (ICP) algorithm.
// The core of the algorithm is to match each vertex in one surface with 
// the closest surface point on the other, then apply the transformation
// that modify one surface to best match the other (in a least square sense).
// This has to be iterated to get proper convergence of the surfaces.
// .SECTION Note
// Use vtkTransformPolyDataFilter to apply the resulting ICP transform to 
// your data. You might also set it to your actor's user transform.
// .SECTION Note
// This class makes use of vtkLandmarkTransform internally to compute the
// best fit. Use the GetLandmarkTransform member to get a pointer to that
// transform and set its parameters. You might, for example, constrain the
// number of degrees of freedom of the solution (i.e. rigid body, similarity,
// etc.) by checking the vtkLandmarkTransform documentation for its SetMode
// member.
// .SECTION see also
// vtkLandmarkTransform


#ifndef __vtkIterativeClosestPointTransform_h
#define __vtkIterativeClosestPointTransform_h

#include "vtkLinearTransform.h"

#define VTK_ICP_MODE_RMS 0
#define VTK_ICP_MODE_AV 1

class vtkCellLocator;
class vtkLandmarkTransform;
class vtkDataSet;

class VTK_HYBRID_EXPORT vtkIterativeClosestPointTransform : public vtkLinearTransform
{
public:
  static vtkIterativeClosestPointTransform *New();
  vtkTypeRevisionMacro(vtkIterativeClosestPointTransform,vtkLinearTransform);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Specify the source and target data sets.
  void SetSource(vtkDataSet *source);
  void SetTarget(vtkDataSet *target);
  vtkGetObjectMacro(Source, vtkDataSet);
  vtkGetObjectMacro(Target, vtkDataSet);

  // Description:
  // Set/Get a spatial locator for speeding up the search process. 
  // An instance of vtkCellLocator is used by default.
  void SetLocator(vtkCellLocator *locator);
  vtkGetObjectMacro(Locator,vtkCellLocator);

  // Description: 
  // Set/Get the  maximum number of iterations
  vtkSetMacro(MaximumNumberOfIterations, int);
  vtkGetMacro(MaximumNumberOfIterations, int);

  // Description: 
  // Get the number of iterations since the last update
  vtkGetMacro(NumberOfIterations, int);

  // Description: 
  // Force the algorithm to check the mean distance between two iteration.
  vtkSetMacro(CheckMeanDistance, int);
  vtkGetMacro(CheckMeanDistance, int);
  vtkBooleanMacro(CheckMeanDistance, int);

  // Description:
  // Specify the mean distance mode. This mode expresses how the mean 
  // distance is computed. The RMS mode is the square root of the average
  // of the sum of squares of the closest point distances. The Absolute
  // Value mode is the mean of the sum of absolute values of the closest
  // point distances.
  vtkSetClampMacro(MeanDistanceMode,int,
                   VTK_ICP_MODE_RMS,VTK_ICP_MODE_AV);
  vtkGetMacro(MeanDistanceMode,int);
  void SetMeanDistanceModeToRMS()
    {this->SetMeanDistanceMode(VTK_ICP_MODE_RMS);}
  void SetMeanDistanceModeToAbsoluteValue()
    {this->SetMeanDistanceMode(VTK_ICP_MODE_AV);}
  const char *GetMeanDistanceModeAsString();

  // Description: 
  // Set/Get the maximum mean distance between two iteration. If the mean
  // distance is lower than this, the convergence stops.
  vtkSetMacro(MaximumMeanDistance, double);
  vtkGetMacro(MaximumMeanDistance, double);
  
  // Description: 
  // Get the mean distance between the last two iterations.
  vtkGetMacro(MeanDistance, double);
  
  // Description: 
  // Set/Get the maximum number of landmarks sampled in your dataset.
  // If your dataset is dense, then you will typically not need all the 
  // points to compute the ICP transform. 
  vtkSetMacro(MaximumNumberOfLandmarks, int);
  vtkGetMacro(MaximumNumberOfLandmarks, int);

  // Description: 
  // Starts the process by translating source centroid to target centroid.
  vtkSetMacro(StartByMatchingCentroids, int);
  vtkGetMacro(StartByMatchingCentroids, int);
  vtkBooleanMacro(StartByMatchingCentroids, int);

  // Description: 
  // Get the internal landmark transform. Use it to constrain the number of
  // degrees of freedom of the solution (i.e. rigid body, similarity, etc.).
  vtkGetObjectMacro(LandmarkTransform,vtkLandmarkTransform);
  
  // Description:
  // Invert the transformation.  This is done by switching the
  // source and target.
  void Inverse();

  // Description:
  // Make another transform of the same type.
  vtkAbstractTransform *MakeTransform();

protected:

  // Description:
  // Release source and target
  void ReleaseSource(void);
  void ReleaseTarget(void);

  // Description:
  // Release locator
  void ReleaseLocator(void);

  // Description:
  // Create default locator. Used to create one when none is specified.
  void CreateDefaultLocator(void);

  // Description:
  // Get the MTime of this object also considering the locator.
  unsigned long int GetMTime();

  vtkIterativeClosestPointTransform();
  ~vtkIterativeClosestPointTransform();

  void InternalUpdate();

  // Description:
  // This method does no type checking, use DeepCopy instead.
  void InternalDeepCopy(vtkAbstractTransform *transform);

  vtkDataSet* Source;
  vtkDataSet* Target;
  vtkCellLocator *Locator;
  int MaximumNumberOfIterations;
  int CheckMeanDistance;
  int MeanDistanceMode;
  double MaximumMeanDistance;
  int MaximumNumberOfLandmarks;
  int StartByMatchingCentroids;

  int NumberOfIterations;
  double MeanDistance;
  vtkLandmarkTransform *LandmarkTransform;
private:
  vtkIterativeClosestPointTransform(const vtkIterativeClosestPointTransform&);  // Not implemented.
  void operator=(const vtkIterativeClosestPointTransform&);  // Not implemented.
};

#endif
