// @(#)root/gl:$Id$
// 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_TGLOrthoCamera
#define ROOT_TGLOrthoCamera

#include "TGLCamera.h"


//////////////////////////////////////////////////////////////////////////
//                                                                      //
// TGLOrthoCamera                                                       //
//                                                                      //
// Orthographic projection camera. Currently limited to three types     //
// defined at construction time - kXOY, kXOZ, kZOY - where this refers  //
// to the viewport plane axis - e.g. kXOY has X axis horizontal, Y      //
// vertical - i.e. looking down Z axis with Y vertical.                 //
//
// The plane types restriction could easily be removed to supported     //
// arbitary ortho projections along any axis/orientation with free      //
// rotations about them.                                                //
//                                                                      //
//////////////////////////////////////////////////////////////////////////

class TGLPaintDevice;

class TGLOrthoCamera : public TGLCamera
{
public:
   enum EType { kZOY,  kXOZ,  kXOY,    // Pair of world axes aligned to h/v screen.
                kZnOY, kXnOZ, kXnOY, kZOX, kZnOX}; // 'n' means preceding axis is negated.
private:
   // Fields
   EType          fType;         // camera type
   Bool_t         fEnableRotate; // enable rotation
   Bool_t         fDollyToZoom;  // zoom when dolly is requested

   // Limits - set in Setup()
   Double_t       fZoomMin;      //  minimum zoom factor
   Double_t       fZoomDefault;  //  default zoom factor
   Double_t       fZoomMax;      //  maximum zoom factor
   TGLBoundingBox fVolume;       //! scene volume

   // Current interaction
   Double_t       fDefXSize, fDefYSize; //! x, y size of scene from camera view
   Double_t       fZoom;                //  current zoom

   static UInt_t  fgZoomDeltaSens;

public:
   TGLOrthoCamera();
   TGLOrthoCamera(EType type, const TGLVector3 & hAxis, const TGLVector3 & vAxis);
   virtual ~TGLOrthoCamera();

   virtual Bool_t IsOrthographic() const { return kTRUE; }

   virtual void   Setup(const TGLBoundingBox & box, Bool_t reset=kTRUE);
   virtual void   Reset();

   virtual Bool_t Dolly(Int_t delta, Bool_t mod1, Bool_t mod2);
   virtual Bool_t Zoom (Int_t delta, Bool_t mod1, Bool_t mod2);
   using   TGLCamera::Truck;
   virtual Bool_t Truck(Int_t xDelta, Int_t yDelta, Bool_t mod1, Bool_t mod2);
   virtual Bool_t Rotate(Int_t xDelta, Int_t yDelta, Bool_t mod1, Bool_t mod2);
   virtual void   Apply(const TGLBoundingBox & sceneBox, const TGLRect * pickRect = 0) const;

   // External scripting control
   //   void Configure(Double_t left, Double_t right, Double_t top, Double_t bottom);
   virtual void Configure(Double_t zoom, Double_t dolly, Double_t center[3],
                          Double_t hRotate, Double_t vRotate);

   void     SetEnableRotate(Bool_t x) { fEnableRotate = x; }
   Bool_t   GetEnableRotate()   const { return fEnableRotate; }

   Double_t GetZoomMin() const { return fZoomMin; }
   Double_t GetZoomMax() const { return fZoomMax; }
   void     SetZoomMin(Double_t z);
   void     SetZoomMax(Double_t z);
   void     SetZoomMinMax(Double_t min, Double_t max) { SetZoomMin(min); SetZoomMax(max); }

   void     SetDollyToZoom(Bool_t x) { fDollyToZoom = x; }
   Bool_t   GetDollyToZoom()   const { return fDollyToZoom; }

   void     SetZoom(Double_t x) { fZoom = x; }
   Double_t GetZoom() const { return fZoom; }

   ClassDef(TGLOrthoCamera,1) // Camera for orthographic view.
};

#endif // ROOT_TGLOrthoCamera
