// Copyright (c) 2018 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 _Graphic3d_AttribBuffer_HeaderFile
#define _Graphic3d_AttribBuffer_HeaderFile

#include <Graphic3d_Buffer.hxx>

//! Buffer of vertex attributes.
//! This class is intended for advanced usage allowing invalidation of entire buffer content or its sub-part.
class Graphic3d_AttribBuffer : public Graphic3d_Buffer
{
  DEFINE_STANDARD_RTTIEXT(Graphic3d_AttribBuffer, Graphic3d_Buffer)
public:
  //! Empty constructor.
  Standard_EXPORT Graphic3d_AttribBuffer (const Handle(NCollection_BaseAllocator)& theAlloc);

  //! Allocates new empty array
  Standard_EXPORT bool Init (const Standard_Integer     theNbElems,
                             const Graphic3d_Attribute* theAttribs,
                             const Standard_Integer     theNbAttribs);

  //! Allocates new empty array
  bool Init (const Standard_Integer             theNbElems,
             const Graphic3d_Array1OfAttribute& theAttribs)
  {
    return Init (theNbElems, &theAttribs.First(), theAttribs.Size());
  }

  //! Return TRUE if data can be invalidated; FALSE by default.
  virtual Standard_Boolean IsMutable() const Standard_OVERRIDE { return myIsMutable; }

  //! Set if data can be invalidated.
  Standard_EXPORT void SetMutable (Standard_Boolean theMutable);

  //! Return TRUE for interleaved array; TRUE by default.
  virtual Standard_Boolean IsInterleaved() const Standard_OVERRIDE { return myIsInterleaved; }

  //! Setup interleaved/non-interleaved array.
  //! WARNING! Filling non-interleaved buffer should be implemented on user side
  //!          without Graphic3d_Buffer auxiliary methods designed for interleaved data.
  Standard_EXPORT void SetInterleaved (Standard_Boolean theIsInterleaved);

  //! Return invalidated range.
  virtual Graphic3d_BufferRange InvalidatedRange() const Standard_OVERRIDE { return myInvalidatedRange; }

  //! Reset invalidated range.
  virtual void Validate() Standard_OVERRIDE { myInvalidatedRange.Clear(); }

  //! Invalidate the entire buffer data.
  Standard_EXPORT virtual void Invalidate() Standard_OVERRIDE;

  //! Invalidate the entire attribute data.
  Standard_EXPORT void Invalidate (Standard_Integer theAttributeIndex);

  //! Invalidate attribute data within specified sub-range (starting from 0).
  Standard_EXPORT void Invalidate (Standard_Integer theAttributeIndex,
                                   Standard_Integer theVertexLower,
                                   Standard_Integer theVertexUpper);

  //! Invalidate all attribute data within specified vertex sub-range (starting from 0).
  Standard_EXPORT void Invalidate (Standard_Integer theVertexLower,
                                   Standard_Integer theVertexUpper);

  //! Invalidate specified sub-range of data (as byte offsets).
  Standard_EXPORT void invalidate (const Graphic3d_BufferRange& theRange);

protected:
  Graphic3d_BufferRange myInvalidatedRange; //!< invalidated buffer data range (as byte offsets)
  Standard_Boolean      myIsInterleaved;    //!< flag indicating the vertex attributes being interleaved
  Standard_Boolean      myIsMutable;        //!< flag indicating that data can be invalidated
};

#endif // _Graphic3d_AttribBuffer_HeaderFile