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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkHomogeneousTransform.h,v $
  Language:  C++
  Date:      $Date: 2001/11/30 19:14:13 $
  Version:   $Revision: 1.12 $
  Thanks:    Thanks to David G. Gobbi who developed this class.

Copyright (c) 1993-2001 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 AUTHORS OR CONTRIBUTORS BE LIABLE FOR
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DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/
// .NAME vtkHomogeneousTransform - superclass for homogeneous transformations
// .SECTION Description
// vtkHomogeneousTransform provides a generic interface for homogeneous 
// transformations, i.e. transformations which can be represented by 
// multiplying a 4x4 matrix with a homogeneous coordinate. 
// .SECTION see also
// vtkPerspectiveTransform vtkLinearTransform vtkIdentityTransform


#ifndef __vtkHomogeneousTransform_h
#define __vtkHomogeneousTransform_h

#include "vtkAbstractTransform.h"
#include "vtkMatrix4x4.h"

class VTK_COMMON_EXPORT vtkHomogeneousTransform : public vtkAbstractTransform
{
public:

  vtkTypeMacro(vtkHomogeneousTransform,vtkAbstractTransform);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Apply the transformation to a series of points, and append the
  // results to outPts.  
  void TransformPoints(vtkPoints *inPts, vtkPoints *outPts);

  // Description:
  // Apply the transformation to a combination of points, normals
  // and vectors.  
  virtual void TransformPointsNormalsVectors(vtkPoints *inPts, 
                                             vtkPoints *outPts, 
                                             vtkDataArray *inNms, 
                                             vtkDataArray *outNms,
                                             vtkDataArray *inVrs, 
                                             vtkDataArray *outVrs);

  // Description:
  // Get a copy of the internal transformation matrix.  The
  // transform is Updated first, to guarantee that the matrix
  // is valid.
  void GetMatrix(vtkMatrix4x4 *m);

  // Description:
  // Get a pointer to an internal vtkMatrix4x4 that represents
  // the transformation.  An Update() is called on the transform
  // to ensure that the matrix is up-to-date when you get it.
  // You should not store the matrix pointer anywhere because it
  // might become stale.
  vtkMatrix4x4 *GetMatrix() { this->Update(); return this->Matrix; };

  // Description:
  // Just like GetInverse(), but includes typecast to vtkHomogeneousTransform.
  vtkHomogeneousTransform *GetHomogeneousInverse() {
    return (vtkHomogeneousTransform *)this->GetInverse(); };

  // Description:
  // This will calculate the transformation without calling Update.
  // Meant for use only within other VTK classes.
  void InternalTransformPoint(const float in[3], float out[3]);
  void InternalTransformPoint(const double in[3], double out[3]);

  // Description:
  // This will calculate the transformation as well as its derivative
  // without calling Update.  Meant for use only within other VTK
  // classes.
  void InternalTransformDerivative(const float in[3], float out[3],
                                   float derivative[3][3]);
  void InternalTransformDerivative(const double in[3], double out[3],
                                   double derivative[3][3]);

protected:
  vtkHomogeneousTransform();
  ~vtkHomogeneousTransform();

  void InternalDeepCopy(vtkAbstractTransform *transform);

  vtkMatrix4x4 *Matrix;
private:
  vtkHomogeneousTransform(const vtkHomogeneousTransform&);  // Not implemented.
  void operator=(const vtkHomogeneousTransform&);  // Not implemented.
};

#endif





