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

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


Copyright (c) 1993-1998 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.

THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES, INCLUDING,
BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE, AND NON-INFRINGEMENT.  THIS SOFTWARE IS PROVIDED ON AN
"AS IS" BASIS, AND THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.


=========================================================================*/
// .NAME vtkContourFilter - generate isosurfaces/isolines from scalar values
// .SECTION Description
// vtkContourFilter is a filter that takes as input any dataset and 
// generates on output isosurfaces and/or isolines. The exact form 
// of the output depends upon the dimensionality of the input data. 
// Data consisting of 3D cells will generate isosurfaces, data 
// consisting of 2D cells will generate isolines, and data with 1D 
// or 0D cells will generate isopoints. Combinations of output type 
// are possible if the input dimension is mixed.
//
// This filter will identify special dataset types (e.g., structured
// points) and use the appropriate specialized filter to process the
// data. For examples, if the input dataset type is a volume, this
// filter will create an internal vtkMarchingCubes instance and use
// it. This gives much better performance.
// 
// To use this filter you must specify one or more contour values.
// You can either use the method SetValue() to specify each contour
// value, or use GenerateValues() to generate a series of evenly
// spaced contours. It is also possible to accelerate the operation of
// this filter (at the cost of extra memory) by using a
// vtkScalarTree. A scalar tree is used to quickly locate cells that
// contain a contour surface. This is especially effective if multiple
// contours are being extracted. If you want to use a scalar tree,
// invoke the method UseScalarTreeOn().

// .SECTION Caveats
// For unstructured data or structured grids, normals and gradients
// are not computed.  This calculation will be implemented in the
// future. In the mean time, use vtkPolyDataNormals to compute the surface
// normals.

// .SECTION See Also
// vtkMarchingCubes vtkSliceCubes vtkDividingCubes vtkMarchingSquares

#ifndef __vtkContourFilter_h
#define __vtkContourFilter_h

#include "vtkDataSetToPolyDataFilter.h"
#include "vtkContourValues.h"

class vtkScalarTree;

class VTK_EXPORT vtkContourFilter : public vtkDataSetToPolyDataFilter
{
public:
  vtkContourFilter();
  static vtkContourFilter *New() {return new vtkContourFilter;};
  ~vtkContourFilter();
  const char *GetClassName() {return "vtkContourFilter";};
  void PrintSelf(ostream& os, vtkIndent indent);

  // Methods to set contour values
  void SetValue(int i, float value);
  float GetValue(int i);
  float *GetValues();
  void GetValues(float *contourValues);
  void SetNumberOfContours(int number);
  int GetNumberOfContours();
  void GenerateValues(int numContours, float range[2]);
  void GenerateValues(int numContours, float rangeStart, float rangeEnd);

  // Because we delegate to vtkContourValues
  unsigned long int GetMTime();

  // Description:
  // Set/Get the computation of normals. Normal computation is failrly expensive
  // in both time and storage. If the output data will be processed by filters
  // that modify topology or geometry, it may be wise to turn Normals and Gradients off.
  vtkSetMacro(ComputeNormals,int);
  vtkGetMacro(ComputeNormals,int);
  vtkBooleanMacro(ComputeNormals,int);

  // Description:
  // Set/Get the computation of gradients. Gradient computation is fairly expensive
  // in both time and storage. Note that if ComputeNormals is on, gradients will
  // have to be calculated, but will not be stored in the output dataset.
  // If the output data will be processed by filters that modify topology or
  // geometry, it may be wise to turn Normals and Gradients off.
  vtkSetMacro(ComputeGradients,int);
  vtkGetMacro(ComputeGradients,int);
  vtkBooleanMacro(ComputeGradients,int);

  // Description:
  // Set/Get the computation of scalars.
  vtkSetMacro(ComputeScalars,int);
  vtkGetMacro(ComputeScalars,int);
  vtkBooleanMacro(ComputeScalars,int);

  // Description:
  // Enable the use of a scalar tree to accelerate contour extraction.
  vtkSetMacro(UseScalarTree,int);
  vtkGetMacro(UseScalarTree,int);
  vtkBooleanMacro(UseScalarTree,int);

  void SetLocator(vtkPointLocator *locator);
  void SetLocator(vtkPointLocator& locator) {this->SetLocator(&locator);};
  vtkGetObjectMacro(Locator,vtkPointLocator);

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

protected:
  void Execute();

  vtkContourValues *ContourValues;
  int ComputeNormals;
  int ComputeGradients;
  int ComputeScalars;
  vtkPointLocator *Locator;
  int UseScalarTree;
  vtkScalarTree *ScalarTree;

  void StructuredPointsContour(int dim); //special contouring for structured points
};

// Description:
// Set a particular contour value at contour number i. The index i ranges 
// between 0<=i<NumberOfContours.
inline void vtkContourFilter::SetValue(int i, float value)
{this->ContourValues->SetValue(i,value);}

// Description:
// Get the ith contour value.
inline float vtkContourFilter::GetValue(int i)
{return this->ContourValues->GetValue(i);}

// Description:
// Get a pointer to an array of contour values. There will be
// GetNumberOfContours() values in the list.
inline float *vtkContourFilter::GetValues()
{return this->ContourValues->GetValues();}

// Description:
// Fill a supplied list with contour values. There will be
// GetNumberOfContours() values in the list. Make sure you allocate
// enough memory to hold the list.
inline void vtkContourFilter::GetValues(float *contourValues)
{this->ContourValues->GetValues(contourValues);}

// Description:
// Set the number of contours to place into the list. You only really
// need to use this method to reduce list size. The method SetValue()
// will automatically increase list size as needed.
inline void vtkContourFilter::SetNumberOfContours(int number)
{this->ContourValues->SetNumberOfContours(number);}

// Description:
// Get the number of contours in the list of contour values.
inline int vtkContourFilter::GetNumberOfContours()
{return this->ContourValues->GetNumberOfContours();}

// Description:
// Generate numContours equally spaced contour values between specified
// range. Contour values will include min/max range values.
inline void vtkContourFilter::GenerateValues(int numContours, float range[2])
{this->ContourValues->GenerateValues(numContours, range);}

// Description:
// Generate numContours equally spaced contour values between specified
// range. Contour values will include min/max range values.
inline void vtkContourFilter::GenerateValues(int numContours, float
                                             rangeStart, float rangeEnd)
{this->ContourValues->GenerateValues(numContours, rangeStart, rangeEnd);}


#endif


