// @(#)root/gl:$Id: TGLPerspectiveCamera.h 20882 2007-11-19 11:31:26Z rdm $
// Author:  Richard Maunder  25/05/2005

/*************************************************************************
 * Copyright (C) 1995-2004, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

#ifndef ROOT_TGLPerspectiveCamera
#define ROOT_TGLPerspectiveCamera

#ifndef ROOT_TGLCamera
#include "TGLCamera.h"
#endif

//////////////////////////////////////////////////////////////////////////
//                                                                      //
// TGLPerspectiveCamera                                                 //
//                                                                      //
// Perspective projection camera - with characteristic foreshortening.  //
//                                                                      //
// TODO: Currently constrains YOZ plane to be floor - this is never     //
// 'tipped'. While useful we really need to extend so can:              //
// i) Pick any one of the three natural planes of the world to be floor.//
// ii) Can use a free arcball style camera with no contraint - integrate//
// TArcBall.                                                            //
//////////////////////////////////////////////////////////////////////////

class TGLPerspectiveCamera : public TGLCamera
{
private:
   // Fields
   Double_t    fFOV;             //!

   static   Double_t fgFOVMin, fgFOVDefault, fgFOVMax;
   static   UInt_t   fgFOVDeltaSens;
public:
   TGLPerspectiveCamera(const TGLVector3 & hAxis, const TGLVector3 & vAxis);
   virtual ~TGLPerspectiveCamera();

   virtual void   Setup(const TGLBoundingBox & box, Bool_t reset=kTRUE);
   virtual void   Reset();
   virtual Bool_t Zoom (Int_t delta, Bool_t mod1, Bool_t mod2);
   virtual void   Apply(const TGLBoundingBox & box, const TGLRect * pickRect = 0) const;

   // External scripting control
   virtual void Configure(Double_t fov, Double_t dolly, Double_t center[3],
                          Double_t hRotate, Double_t vRotate);

   ClassDef(TGLPerspectiveCamera,0) // a perspective view camera
};

#endif // ROOT_TGLPerspectiveCamera