text: /*=========================================================================
  
    Program:   Visualization Toolkit
    Module:    vtkCompositeControlPointsItem.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 vtkCompositeControlPointsItem - Control points for
  // vtkCompositeFunction.
  // .SECTION Description
  // vtkCompositeControlPointsItem draws the control points of a vtkPiecewiseFunction
  // and a vtkColorTransferFunction.
  // .SECTION See Also
  // vtkControlPointsItem
  // vtkColorTransferControlPointsItem
  // vtkCompositeTransferFunctionItem
  
  #ifndef __vtkCompositeControlPointsItem_h
  #define __vtkCompositeControlPointsItem_h
  
  #include "vtkColorTransferControlPointsItem.h"
  
  class vtkPiecewiseFunction;
  
  class VTK_CHARTS_EXPORT vtkCompositeControlPointsItem:
    public vtkColorTransferControlPointsItem
  {
  public:
    vtkTypeMacro(vtkCompositeControlPointsItem, vtkColorTransferControlPointsItem);
    virtual void PrintSelf(ostream &os, vtkIndent indent);
  
    // Description:
    // Creates a piecewise control points object
    static vtkCompositeControlPointsItem* New();
  
    // Description:
    // Set the color transfer function to draw its points
    virtual void SetColorTransferFunction(vtkColorTransferFunction* function);
  
    // Description
    // Utility function that calls SetPiecewiseFunction()
    void SetOpacityFunction(vtkPiecewiseFunction* opacity);
    vtkGetObjectMacro(OpacityFunction, vtkPiecewiseFunction);
  
    enum PointsFunction{
      ColorPointsFunction = 1,
      OpacityPointsFunction = 2,
      ColorAndOpacityPointsFunction = 3
    };
    // Description:
    // PointsFunction controls wether the points represent the 
    // ColorTransferFunction, OpacityTransferFunction or both.
    // If ColorPointsFunction, only the points of the ColorTransfer function are
    // used.
    // If OpacityPointsFunction, only the points of the Opacity function are used
    // If ColorAndOpacityPointsFunction, the points of both functions are shared
    // by both functions.
    // ColorAndOpacityPointsFunction by default.
    // Note: Set the mode before the functions are set. ColorPointsFunction is
    // not fully supported.
    vtkSetMacro(PointsFunction, int);
    vtkGetMacro(PointsFunction, int);
  
    // Description:
    // Add a point to the function. Returns the index of the point (0 based),
    // or -1 on error.
    // Subclasses should reimplement this function to do the actual work.
    virtual vtkIdType AddPoint(double* newPos);
  
    // Description:
    // Remove a point of the function. Returns the index of the point (0 based),
    // or -1 on error.
    // Subclasses should reimplement this function to do the actual work.
    virtual vtkIdType RemovePoint(double* pos);
  
  protected:
    vtkCompositeControlPointsItem();
    virtual ~vtkCompositeControlPointsItem();
  
    virtual unsigned long int GetControlPointsMTime();
    virtual void ComputePoints();
  
    virtual int GetNumberOfPoints()const;
    virtual void DrawPoint(vtkContext2D* painter, vtkIdType index);
    virtual void GetControlPoint(vtkIdType index, double* pos);
    virtual void SetControlPoint(vtkIdType index, double *point);
    virtual void EditPoint(float tX, float tY);
  
    void MergeTransferFunctions();
    void SilentMergeTransferFunctions();
  
    int                   PointsFunction;
    vtkPiecewiseFunction* OpacityFunction;
    bool                  Updating;
  
  private:
    vtkCompositeControlPointsItem(const vtkCompositeControlPointsItem &); // Not implemented.
    void operator=(const vtkCompositeControlPointsItem &);   // Not implemented.
  };
  
  #endif
  