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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkImporter.h,v $

  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 vtkImporter - importer abstract class
// .SECTION Description
// vtkImporter is an abstract class that specifies the protocol for
// importing actors, cameras, lights and properties into a
// vtkRenderWindow. The following takes place:
// 1) Create a RenderWindow and Renderer if none is provided.
// 2) Call ImportBegin, if ImportBegin returns False, return
// 3) Call ReadData, which calls:
//  a) Import the Actors
//  b) Import the cameras
//  c) Import the lights
//  d) Import the Properties
// 7) Call ImportEnd
//
// Subclasses optionally implement the ImportActors, ImportCameras,
// ImportLights and ImportProperties or ReadData methods. An ImportBegin and
// ImportEnd can optionally be provided to perform Importer-specific
// initialization and termination.  The Read method initiates the import
// process. If a RenderWindow is provided, its Renderer will contained
// the imported objects. If the RenderWindow has no Renderer, one is
// created. If no RenderWindow is provided, both a RenderWindow and
// Renderer will be created. Both the RenderWindow and Renderer can be
// accessed using Get methods.

// .SECTION See Also
// vtk3DSImporter vtkExporter

#ifndef __vtkImporter_h
#define __vtkImporter_h

#include "vtkObject.h"

class vtkRenderWindow;
class vtkRenderer;

class VTK_RENDERING_EXPORT vtkImporter : public vtkObject
{
public:
  vtkTypeRevisionMacro(vtkImporter,vtkObject);
  void PrintSelf(ostream& os, vtkIndent indent);


  // Description
  // Get the renderer that contains the imported actors, cameras and
  // lights.
  vtkGetObjectMacro(Renderer,vtkRenderer);

  // Description
  // Set the vtkRenderWindow to contain the imported actors, cameras and
  // lights, If no vtkRenderWindow is set, one will be created and can be
  // obtained with the GetRenderWindow method. If the vtkRenderWindow has been
  // specified, the first vtkRenderer it has will be used to import the
  // objects. If the vtkRenderWindow has no Renderer, one will be created and
  // can be accessed using GetRenderer.
  virtual void SetRenderWindow(vtkRenderWindow*);
  vtkGetObjectMacro(RenderWindow,vtkRenderWindow);


  // Description
  // Import the actors, cameras, lights and properties into a vtkRenderWindow.
  void Read();
  void Update() {this->Read();};
  

protected:
  vtkImporter();
  ~vtkImporter();

  virtual int ImportBegin () {return 1;};
  virtual void ImportEnd () {};
  virtual void ImportActors (vtkRenderer*) {};
  virtual void ImportCameras (vtkRenderer*) {};
  virtual void ImportLights (vtkRenderer*) {};
  virtual void ImportProperties (vtkRenderer*) {};

  vtkRenderer *Renderer;
  vtkRenderWindow *RenderWindow;

  virtual void ReadData();

private:
  vtkImporter(const vtkImporter&);  // Not implemented.
  void operator=(const vtkImporter&);  // Not implemented.
};

#endif




