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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkOverlayPass.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 vtkOverlayPass - Render the overlay geometry with property key
// filtering.
// .SECTION Description
// vtkOverlayPass renders the overlay geometry of all the props that have the
// keys contained in vtkRenderState.
//
// This pass expects an initialized depth buffer and color buffer.
// Initialized buffers means they have been cleared with farest z-value and
// background color/gradient/transparent color.
// 
// .SECTION See Also
// vtkRenderPass vtkDefaultPass

#ifndef __vtkOverlayPass_h
#define __vtkOverlayPass_h

#include "vtkDefaultPass.h"

class VTK_RENDERING_EXPORT vtkOverlayPass : public vtkDefaultPass
{
public:
  static vtkOverlayPass *New();
  vtkTypeRevisionMacro(vtkOverlayPass,vtkDefaultPass);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Perform rendering according to a render state \p s.
  // \pre s_exists: s!=0
  virtual void Render(const vtkRenderState *s);
  
 protected:
  // Description:
  // Default constructor.
  vtkOverlayPass();

  // Description:
  // Destructor.
  virtual ~vtkOverlayPass();
  
 private:
  vtkOverlayPass(const vtkOverlayPass&);  // Not implemented.
  void operator=(const vtkOverlayPass&);  // Not implemented.
};

#endif
