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

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


Copyright (c) 1993-1996 Ken Martin, Will Schroeder, Bill Lorensen.

This software is copyrighted by Ken Martin, Will Schroeder and Bill Lorensen.
The following terms apply to all files associated with the software unless
explicitly disclaimed in individual files. This copyright specifically does
not apply to the related textbook "The Visualization Toolkit" ISBN
013199837-4 published by Prentice Hall which is covered by its own copyright.

The authors hereby grant permission to use, copy, and distribute this
software and its documentation for any purpose, provided that existing
copyright notices are retained in all copies and that this notice is included
verbatim in any distributions. Additionally, the authors grant permission to
modify this software and its documentation for any purpose, provided that
such modifications are not distributed without the explicit consent of the
authors and that existing copyright notices are retained in all copies. Some
of the algorithms implemented by this software are patented, observe all
applicable patent law.

IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY DERIVATIVES THEREOF,
EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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=========================================================================*/
// .NAME vtkSweptSurface - given a path and input geometry generate an (implicit) representation of a swept surface
// .SECTION Description
// vtkSweptSurface is a filter that is used to create a surface defined by 
// moving a part along a path. In this implementation, the path is defined as
// a list of transformation matrices (vtkTransform), and the part geometry is
// implicitly defined using a volume (i.e., distance scalars in structured 
// point dataset). The input to the filter is the geometry (i.e., a 
// structured point dataset) and the output is a structured point dataset 
// (i.e., an implicit representation of the swept surface). If you wish to
// generate a polygonal representation of swept surface you will have to 
// use a contouring filter (e.g., vtkContourFilter). (You may also wish to
// use vtkDecimate to reduce mesh size.)
//
// The swept surface algorithm can be summarized as follows. A geometry 
// (i.e. the input) is swept along a path (list of transforms). At each point
// on the path the input is re-sampled into a volume using a union operation.
// (Union means that the minimum scalar value is retained - minimum distance
// value for example.) At the end, an implicit representation of the swept
// surface is defined.
// .SECTION See Also
// vtkImplicitModeller vtkContourFilter vtkDecimate

#ifndef __vtkSweptSurface_h
#define __vtkSweptSurface_h

#include "vtkStructuredPointsToStructuredPointsFilter.h"
#include "vtkTransformCollection.h"

class VTK_EXPORT vtkSweptSurface : public vtkStructuredPointsToStructuredPointsFilter
{
public:
  vtkSweptSurface();
  char *GetClassName() {return "vtkSweptSurface";};
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Specify i-j-k dimensions to sample input with. The higher the resolution
  // the lower the error but the greater the processing time.
  vtkSetVector3Macro(SampleDimensions,int);
  vtkGetVectorMacro(SampleDimensions,int,3);

  // Description:
  // Specify a path (i.e., list of transforms) that the input moves along. At
  // least two transforms must be used to define a path.
  vtkSetObjectMacro(Transforms, vtkTransformCollection);
  vtkGetObjectMacro(Transforms, vtkTransformCollection);

  // Description:
  // Voxels are initialized to this value. By default a large floating point
  // value is used, since the scalar values are assumed to be a distance 
  // function.
  vtkSetMacro(FillValue,float);
  vtkGetMacro(FillValue,float);

  // Description:
  // Value specifies/controls interpolation between the nodes (i.e., 
  // transforms) defining the path. A positive value indicates the number
  // of steps to take between transforms (i.e., interpolation is performed).
  // A negative value indicates that no interpolation to be performed, that is,
  // only the points defined at each transform are used (interpolation not
  // performed). A zero value indicates that automatic interpolation is to be
  // performed, that is, interpolation is computed so that potential errors 
  // fall below the error bounds defined in the text. By default, automatic
  // computation is performed (Interpolation = 0).
  vtkSetMacro(NumberOfInterpolationSteps,int);
  vtkGetMacro(NumberOfInterpolationSteps,int);

  // Description:
  // Set/get the maximum number of interpolation steps to take. This is useful
  // if you are limited in computation time or just know that the number of 
  // computed steps should not exceed a certain value.
  vtkSetMacro(MaximumNumberOfInterpolationSteps,int);
  vtkGetMacro(MaximumNumberOfInterpolationSteps,int);

  // Description:
  // The outer boundary of the sampling volume can be capped (i.e., assigned 
  // fill value). This will "close" the implicit model if the geometry 
  // approaches close to or passes through the boundary of the volume (i.e.,
  // defined by ModelBounds instance variable). Capping turns on/off this 
  // capability. By default capping is on.
  vtkSetMacro(Capping,int);
  vtkGetMacro(Capping,int);
  vtkBooleanMacro(Capping,int);
  
  // Description:
  // Define the volume (in world coordinates) in which the sampling is to 
  // occur. Make sure that the volume is large enough to accommodate the 
  // motion of the geometry along the path. If the model bounds are set to
  // all zero values, the model bounds will be computed automatically from
  // the input geometry and path.
  vtkSetVectorMacro(ModelBounds,float,6);
  vtkGetVectorMacro(ModelBounds,float,6);
  void SetModelBounds(float xmin, float xmax, float ymin, float ymax, 
                      float zmin, float zmax);

  //overload to check transformation matrices
  unsigned long int GetMTime();

protected:
  void Execute();
  void ComputeBounds(float origin[3], float ar[3], float bbox[24]);
  int ComputeNumberOfSteps(vtkTransform *t1, vtkTransform *t2, float bbox[24]);
  void SampleInput(vtkMatrix4x4& m, int inDim[3], float inOrigin[3],
                   float inAr[3], vtkScalars *in, vtkScalars *out);
  void Cap(vtkFloatScalars *s);

  int SampleDimensions[3];
  float FillValue;
  float ModelBounds[6];
  int NumberOfInterpolationSteps;
  int MaximumNumberOfInterpolationSteps;
  int Capping;

  vtkTransformCollection *Transforms;
};

#endif


