// File:      OpenGl_PrinterContext.hxx
// Created:   20.05.11 10:00:00
// Author:    Anton POLETAEV

#ifndef _OPENGL_PRINTERCONTEXT_H
#define _OPENGL_PRINTERCONTEXT_H

#include <MMgt_TShared.hxx>
#include <Standard.hxx>
#include <Standard_DefineHandle.hxx>
#include <Handle_MMgt_TShared.hxx>
#include <OpenGl_tgl_all.hxx>
#include <NCollection_DataMap.hxx>
#include <InterfaceGraphic_Graphic3d.hxx>
#include <InterfaceGraphic_Visual3d.hxx>
#include <TColStd_Array2OfReal.hxx>

class Standard_Transient;
class Handle(Standard_Type);
class Handle(MMgt_TShared);
class OpenGl_PrinterContext;

DEFINE_STANDARD_HANDLE(OpenGl_PrinterContext,MMgt_TShared)

//! Class provides specific information for redrawing view to offscreen buffer
//! on printing. The information is: projection matrixes for tiling,
//! scaling factors for text/markers and layer viewport dimensions.
//! The OpenGl_PrinterContext class allows to have only one global instance
//! that can be accessed by GetPrinterContext() during printing operation. 
//! The class instance can be created only by call_togl_print().
class OpenGl_PrinterContext : public MMgt_TShared
{

public:

  //! Get the PrinterContext instance assigned for OpenGl context.
  //! Return NULL, if there is no current printing operation and
  //! there is no assigned instance for "theCtx" OpenGl context.
  static OpenGl_PrinterContext* GetPrinterContext(GLCONTEXT theCtx);

  //! Get view projection transformation matrix.
  const TColStd_Array2OfReal& GetProjTransformation () 
  {
    return myProjTransform; 
  }

  //! Get view projection transformation matrix.
  void GetProjTransformation (GLfloat theMatrix[16]); 

  //! Get text/markers scale factor
  void GetScale (GLfloat& theScaleX, GLfloat& theScaleY)
  {
    theScaleX = myScaleX;
    theScaleY = myScaleY;
  }

  //! Get layer viewport dimensions
  void GetLayerViewport (GLsizei& theViewportX,
                         GLsizei& theViewportY)
  {
    theViewportX = myLayerViewportX;
    theViewportY = myLayerViewportY;
  }

private:

  //! Constructor
  OpenGl_PrinterContext (GLCONTEXT theCtx);

  //! Destructor
  virtual ~OpenGl_PrinterContext ();

  //! Deactivate current printing context.
  //! Useful when you need to redraw in usual mode the same OpenGl context
  //! that you used for printing right after printing, before the 
  //! OpenGl_PrinterContext instance destroyed.
  void Deactivate ();

  //! Set view projection transformation matrix for printing/tiling purposes
  //! theProjTransform parameter should be an 4x4 array.
  bool SetProjTransformation (TColStd_Array2OfReal& theProjTransform);

  //! Set text scale factor
  void SetScale (GLfloat theScaleX, GLfloat theScaleY)
  {
    myScaleX = theScaleX;
    myScaleY = theScaleY;
  }

  //! Set layer viewport dimensions
  void SetLayerViewport (GLsizei theViewportX,
                         GLsizei theViewportY) 
  {
    myLayerViewportX = theViewportX; 
    myLayerViewportY = theViewportY;
  }

private:

  static OpenGl_PrinterContext* g_PrinterContext;
  static GLCONTEXT g_ContextId;
  TColStd_Array2OfReal myProjTransform;
  GLfloat              myScaleX;
  GLfloat              myScaleY;
  GLsizei              myLayerViewportX;
  GLsizei              myLayerViewportY;
  GLCONTEXT            myCtx;

  // the printer context could be created only in method call_togl_print
  friend Standard_Boolean call_togl_print (CALL_DEF_VIEW *, CALL_DEF_LAYER *,
                                           CALL_DEF_LAYER *, 
                                           const Aspect_Drawable, const int,
                                           const char*, const int, const float);
};

#endif