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

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

  Copyright (c) 1993-2002 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 vtkOpenGLRenderer - OpenGL renderer
// .SECTION Description
// vtkOpenGLRenderer is a concrete implementation of the abstract class
// vtkRenderer. vtkOpenGLRenderer interfaces to the OpenGL graphics library.

#ifndef __vtkOpenGLRenderer_h
#define __vtkOpenGLRenderer_h

#include "vtkRenderer.h"

class VTK_RENDERING_EXPORT vtkOpenGLRenderer : public vtkRenderer
{
protected:
  int NumberOfLightsBound;

public:
  static vtkOpenGLRenderer *New();
  vtkTypeRevisionMacro(vtkOpenGLRenderer,vtkRenderer);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Concrete open gl render method.
  void DeviceRender(void); 

  // Description:
  // Internal method temporarily removes lights before reloading them
  // into graphics pipeline.
  void ClearLights(void);

  void Clear(void);

  // Description:
  // Ask lights to load themselves into graphics pipeline.
  int UpdateLights(void);
  
protected:
  vtkOpenGLRenderer();
  ~vtkOpenGLRenderer();

  //BTX
  // Picking functions to be implemented by sub-classes
  virtual void DevicePickRender();
  virtual void StartPick(unsigned int pickFromSize);
  virtual void UpdatePickId();
  virtual void DonePick();
  virtual unsigned int GetPickedId();
  virtual float GetPickedZ();
  // Ivars used in picking
  class vtkGLPickInfo* PickInfo;
  //ETX
  float PickedZ;
private:
  vtkOpenGLRenderer(const vtkOpenGLRenderer&);  // Not implemented.
  void operator=(const vtkOpenGLRenderer&);  // Not implemented.
};

#endif
