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

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


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
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/
// .NAME vtkCutter - Cut vtkDataSet with user-specified implicit function
// .SECTION Description
// vtkCutter is a filter to cut through data using any subclass of 
// vtkImplicitFunction. That is, a polygonal surface is created
// corresponding to the implicit function F(x,y,z) = value(s), where
// you can specify one or more values used to cut with.
//
// In VTK, cutting means reducing a cell of dimension N to a cut surface
// of dimension N-1. For example, a tetrahedron when cut by a plane (i.e.,
// vtkPlane implicit function) will generate triangles. (Clipping takes
// a N dimensional cell and creates N dimension primitives.)
//
// vtkCutter is generally used to "slice-through" a dataset, generating
// a surface that can be visualized. It is also possible to use vtkCutter
// to do a form of volume rendering. vtkCutter does this by generating
// multiple cut surfaces (usually planes) which are ordered (and rendered)
// from back-to-front. The surfaces are set translucent to give a 
// volumetric rendering effect.

// .SECTION See Also
// vtkImplicitFunction vtkClipPolyData

#ifndef __vtkCutter_h
#define __vtkCutter_h

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

#define VTK_SORT_BY_VALUE 0
#define VTK_SORT_BY_CELL 1

class VTK_EXPORT vtkCutter : public vtkDataSetToPolyDataFilter
{
public:
  vtkTypeMacro(vtkCutter,vtkDataSetToPolyDataFilter);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Construct with user-specified implicit function; initial value of 0.0; and
  // generating cut scalars turned off.
  static vtkCutter *New();

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

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

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

  // Description:
  // Override GetMTime because we delegate to vtkContourValues and refer to
  // vtkImplicitFunction.
  unsigned long GetMTime();

  // Description
  // Specify the implicit function to perform the cutting.
  vtkSetObjectMacro(CutFunction,vtkImplicitFunction);
  vtkGetObjectMacro(CutFunction,vtkImplicitFunction);

  // Description:
  // If this flag is enabled, then the output scalar values will be
  // interpolated from the implicit function values, and not the input scalar
  // data.
  vtkSetMacro(GenerateCutScalars,int);
  vtkGetMacro(GenerateCutScalars,int);
  vtkBooleanMacro(GenerateCutScalars,int);

  // Description:
  // Specify a spatial locator for merging points. By default, 
  // an instance of vtkMergePoints is used.
  void SetLocator(vtkPointLocator *locator);
  vtkGetObjectMacro(Locator,vtkPointLocator);

  // Description:
  // Set the sorting order for the generated polydata. There are two
  // possibilities:
  //   Sort by value = 0 - This is the most efficient sort. For each cell,
  //      all contour values are processed. This is the default.
  //   Sort by cell = 1 - For each contour value, all cells are processed.
  //      This order should be used if the extracted polygons must be rendered
  //      in a back-to-front or front-to-back order. This is very problem 
  //      dependent.
  // For most applications, the default order is fine (and faster).
  vtkSetClampMacro(SortBy,int,VTK_SORT_BY_VALUE,VTK_SORT_BY_CELL);
  vtkGetMacro(SortBy,int);
  void SetSortByToSortByValue() 
    {this->SetSortBy(VTK_SORT_BY_VALUE);}
  void SetSortByToSortByCell() 
    {this->SetSortBy(VTK_SORT_BY_CELL);}
  const char *GetSortByAsString();

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

#ifndef VTK_REMOVE_LEGACY_CODE
  // Description:
  // For legacy compatibility. Do not use.
  void SetLocator(vtkPointLocator& locator) 
    {VTK_LEGACY_METHOD(SetLocator,"3.2"); this->SetLocator(&locator);}
#endif

protected:
  vtkCutter(vtkImplicitFunction *cf=NULL);
  ~vtkCutter();
  vtkCutter(const vtkCutter&) {};
  void operator=(const vtkCutter&) {};

  void Execute();
  vtkImplicitFunction *CutFunction;
  
  vtkPointLocator *Locator;
  int SortBy;
  vtkContourValues *ContourValues;
  int GenerateCutScalars;
};

// Description:
// Return the sorting procedure as a descriptive character string.
inline const char *vtkCutter::GetSortByAsString(void)
{
  if ( this->SortBy == VTK_SORT_BY_VALUE ) 
    {
    return "SortByValue";
    }
  else 
    {
    return "SortByCell";
    }
}


#endif


