0031082: Visualization - crash on display if there are no lights in the view

[occt.git] / src / OpenGl / OpenGl_PointSprite.hxx

// Created by: Kirill GAVRILOV
// Copyright (c) 2013-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#ifndef _OpenGl_PointSprite_H__
#define _OpenGl_PointSprite_H__

#include <OpenGl_Texture.hxx>

class OpenGl_PointSprite;
DEFINE_STANDARD_HANDLE(OpenGl_PointSprite, OpenGl_Texture)

//! Point sprite resource. On modern hardware it will be texture with extra parameters.
//! On ancient hardware sprites will be drawn using bitmaps.
class OpenGl_PointSprite : public OpenGl_Texture
{
  DEFINE_STANDARD_RTTIEXT(OpenGl_PointSprite, OpenGl_Texture)
public:

  //! Create uninitialized resource.
  Standard_EXPORT OpenGl_PointSprite (const TCollection_AsciiString& theResourceId);

  //! Destroy object.
  Standard_EXPORT virtual ~OpenGl_PointSprite();

  //! Destroy object - will release GPU memory if any.
  Standard_EXPORT virtual void Release (OpenGl_Context* theCtx) Standard_OVERRIDE;

  //! Returns TRUE for point sprite texture.
  virtual bool IsPointSprite() const Standard_OVERRIDE { return true; }

  //! @return true if this is display list bitmap
  inline Standard_Boolean IsDisplayList() const
  {
    return myBitmapList != 0;
  }

  //! Draw sprite using glBitmap.
  //! Please call glRasterPos3fv() before to setup sprite position.
  Standard_EXPORT void DrawBitmap (const Handle(OpenGl_Context)& theCtx) const;

  //! Initialize point sprite as display list
  Standard_EXPORT void SetDisplayList (const Handle(OpenGl_Context)& theCtx,
                                       const GLuint                  theBitmapList);

protected:

  GLuint myBitmapList; //!< if of display list to draw sprite using glBitmap (for backward compatibility)

};

#endif // _OpenGl_PointSprite_H__