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

  Program:   Visualization Toolkit
  Module:    vtkContinuousValueWidget.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.

=========================================================================*/
/*-------------------------------------------------------------------------
  Copyright 2008 Sandia Corporation.
  Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
  the U.S. Government retains certain rights in this software.
-------------------------------------------------------------------------*/

// .NAME vtkContinuousValueWidget - set a value by manipulating something
// .SECTION Description
// The vtkContinuousValueWidget is used to adjust a scalar value in an
// application. Note that the actual appearance of the widget depends on
// the specific representation for the widget.
//
// To use this widget, set the widget representation. (the details may
// vary depending on the particulars of the representation).
//
//
// .SECTION Event Bindings
// By default, the widget responds to the following VTK events (i.e., it
// watches the vtkRenderWindowInteractor for these events):
// <pre>
// If the slider bead is selected:
//   LeftButtonPressEvent - select slider
//   LeftButtonReleaseEvent - release slider
//   MouseMoveEvent - move slider
// </pre>
//
// Note that the event bindings described above can be changed using this
// class's vtkWidgetEventTranslator. This class translates VTK events
// into the vtkContinuousValueWidget's widget events:
// <pre>
//   vtkWidgetEvent::Select -- some part of the widget has been selected
//   vtkWidgetEvent::EndSelect -- the selection process has completed
//   vtkWidgetEvent::Move -- a request for slider motion has been invoked
// </pre>
//
// In turn, when these widget events are processed, the vtkContinuousValueWidget
// invokes the following VTK events on itself (which observers can listen for):
// <pre>
//   vtkCommand::StartInteractionEvent (on vtkWidgetEvent::Select)
//   vtkCommand::EndInteractionEvent (on vtkWidgetEvent::EndSelect)
//   vtkCommand::InteractionEvent (on vtkWidgetEvent::Move)
// </pre>
//

#ifndef vtkContinuousValueWidget_h
#define vtkContinuousValueWidget_h

#include "vtkInteractionWidgetsModule.h" // For export macro
#include "vtkAbstractWidget.h"

class vtkContinuousValueWidgetRepresentation;


class VTKINTERACTIONWIDGETS_EXPORT vtkContinuousValueWidget : public vtkAbstractWidget
{
public:
  // Description:
  // Standard macros.
  vtkTypeMacro(vtkContinuousValueWidget,vtkAbstractWidget);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Specify an instance of vtkWidgetRepresentation used to represent this
  // widget in the scene. Note that the representation is a subclass of vtkProp
  // so it can be added to the renderer independent of the widget.
  void SetRepresentation(vtkContinuousValueWidgetRepresentation *r)
  {this->Superclass::SetWidgetRepresentation
     (reinterpret_cast<vtkWidgetRepresentation*>(r));}

  // Description:
  // Return the representation as a vtkContinuousValueWidgetRepresentation.
  vtkContinuousValueWidgetRepresentation *GetContinuousValueWidgetRepresentation()
    {return reinterpret_cast<vtkContinuousValueWidgetRepresentation*>(this->WidgetRep);}

  // Description:
  // Get the value for this widget.
  double GetValue();
  void SetValue(double v);

protected:
  vtkContinuousValueWidget();
  ~vtkContinuousValueWidget() {}

  // These are the events that are handled
  static void SelectAction(vtkAbstractWidget*);
  static void EndSelectAction(vtkAbstractWidget*);
  static void MoveAction(vtkAbstractWidget*);

  // Manage the state of the widget
  int WidgetState;
  enum _WidgetState
  {
    Start=0,
    Highlighting,
    Adjusting
  };

  double Value;

private:
  vtkContinuousValueWidget(const vtkContinuousValueWidget&) VTK_DELETE_FUNCTION;
  void operator=(const vtkContinuousValueWidget&) VTK_DELETE_FUNCTION;
};

#endif
