text: /*=========================================================================
  
    Program:   Visualization Toolkit
    Module:    vtkPolyDataContourLineInterpolator.h
  
    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 vtkPolyDataContourLineInterpolator - Contour interpolator for polygonal data
  //
  // .SECTION Description
  // vtkPolyDataContourLineInterpolator is an abstract base class for contour
  // line interpolators that interpolate on polygonal data.
  //
  // .SECTION See Also
  
  #ifndef vtkPolyDataContourLineInterpolator_h
  #define vtkPolyDataContourLineInterpolator_h
  
  #include "vtkInteractionWidgetsModule.h" // For export macro
  #include "vtkContourLineInterpolator.h"
  
  class vtkPolyData;
  class vtkPolyDataCollection;
  
  class VTKINTERACTIONWIDGETS_EXPORT vtkPolyDataContourLineInterpolator
                          : public vtkContourLineInterpolator
  {
  public:
    // Description:
    // Standard methods for instances of this class.
    vtkTypeMacro(vtkPolyDataContourLineInterpolator,
                                vtkContourLineInterpolator);
    void PrintSelf(ostream& os, vtkIndent indent);
  
    // Description:
    // Subclasses that wish to interpolate a line segment must implement this.
    // For instance vtkBezierContourLineInterpolator adds nodes between idx1
    // and idx2, that allow the contour to adhere to a bezier curve.
    virtual int InterpolateLine( vtkRenderer *ren,
                                 vtkContourRepresentation *rep,
                                 int idx1, int idx2 ) = 0;
  
    // Description:
    // The interpolator is given a chance to update the node.
    // vtkImageContourLineInterpolator updates the idx'th node in the contour,
    // so it automatically sticks to edges in the vicinity as the user
    // constructs the contour.
    // Returns 0 if the node (world position) is unchanged.
    virtual int UpdateNode( vtkRenderer *,
                            vtkContourRepresentation *,
                            double * vtkNotUsed(node), int vtkNotUsed(idx) ) = 0;
  
    // Description:
    // Be sure to add polydata on which you wish to place points to this list
    // or they will not be considered for placement.
    vtkGetObjectMacro( Polys, vtkPolyDataCollection );
  
  protected:
    vtkPolyDataContourLineInterpolator();
    ~vtkPolyDataContourLineInterpolator();
  
    vtkPolyDataCollection *Polys;
  
  private:
    vtkPolyDataContourLineInterpolator(
        const vtkPolyDataContourLineInterpolator&);  //Not implemented
    void operator=(const vtkPolyDataContourLineInterpolator&);  //Not implemented
  };
  
  #endif
  