library: libGpad #include "TPad.h"

# TPad

class description - source file - inheritance tree (.pdf)

## class TPad : public TVirtualPad

| Inheritance Chart:

`TObject`

`TAttLine`

`TAttFill`

`TAttPad`

`TQObject`

<-

`TVirtualPad`

<-

`TPad`

<-

`TButton`

<-

`TGroupButton` |

`TCanvas`

<-

`TDialogCanvas`

<-

`TAttFillCanvas` |

`TAttLineCanvas` |

`TAttMarkerCanvas` |

`TAttTextCanvas` |

`TDrawPanelHist` |

`TFitPanel` |

[more...]

        private:

                TPad(const TPad& pad)
           void CopyBackgroundPixmap(Int_t x, Int_t y)
           void CopyBackgroundPixmaps(TPad* start, TPad* stop, Int_t x, Int_t y)
          TPad& operator=(const TPad& rhs)

        protected:

                   void DestroyExternalViewer3D()
          virtual Int_t DistancetoPrimitive(Int_t px, Int_t py)
           virtual void ExecuteEvent(Int_t event, Int_t px, Int_t py)
           virtual void HideToolTip(Int_t event)
                   void PaintBorder(Color_t color, Bool_t tops)
           virtual void PaintBorderPS(Double_t xl, Double_t yl, Double_t xt, Double_t yt, Int_t bmode, Int_t bsize, Int_t dark, Int_t light)
                   void PaintDate()
           virtual void SavePrimitive(ofstream& out, Option_t* option)
           virtual void SetBatch(Bool_t batch = kTRUE)

        public:

                                    TPad()
                                    TPad(const char* name, const char* title, Double_t xlow, Double_t ylow, Double_t xup, Double_t yup, Color_t color = -1, Short_t bordersize = -1, Short_t bordermode = -2)
                            virtual ~TPad()
                       virtual void AbsCoordinates(Bool_t set)
                   virtual Double_t AbsPixeltoX(Int_t px)
                       virtual void AbsPixeltoXY(Int_t xpixel, Int_t ypixel, Double_t& x, Double_t& y)
                   virtual Double_t AbsPixeltoY(Int_t py)
                       virtual void AddExec(const char* name, const char* command)
                       virtual void AutoExec()
                       virtual void Browse(TBrowser* b)
                   virtual TLegend* BuildLegend(Double_t x1 = 0.5, Double_t y1 = 0.67, Double_t x2 = 0.88, Double_t y2 = 0.88, const char* title = "")
               virtual TVirtualPad* cd(Int_t subpadnumber = 0)
                     static TClass* Class()
                       virtual void Clear(Option_t* option = "")
                      virtual Int_t Clip(Float_t* x, Float_t* y, Float_t xclipl, Float_t yclipb, Float_t xclipr, Float_t yclipt)
                      virtual Int_t Clip(Double_t* x, Double_t* y, Double_t xclipl, Double_t yclipb, Double_t xclipr, Double_t yclipt)
                      virtual Int_t ClippingCode(Double_t x, Double_t y, Double_t xcl1, Double_t ycl1, Double_t xcl2, Double_t ycl2)
                       virtual void Close(Option_t* option = "")
                       virtual void Closed()
                       virtual void CloseToolTip(TObject* tip)
                       virtual void CopyPixmap()
                       virtual void CopyPixmaps()
                   virtual TObject* CreateToolTip(const TBox* b, const char* text, Long_t delayms)
                       virtual void DeleteExec(const char* name)
                       virtual void DeleteToolTip(TObject* tip)
                       virtual void Divide(Int_t nx = 1, Int_t ny = 1, Float_t xmargin = 0.01, Float_t ymargin = 0.01, Int_t color = 0)
                       virtual void Draw(Option_t* option = "")
                       virtual void DrawClassObject(const TObject* obj, Option_t* option = "")
                        static void DrawColorTable()
                       virtual void DrawCrosshair()
                      virtual TH1F* DrawFrame(Double_t xmin, Double_t ymin, Double_t xmax, Double_t ymax, const char* title = "")
                   virtual TObject* FindObject(const char* name) const
                   virtual TObject* FindObject(const TObject* obj) const
                   virtual Double_t GetAbsHNDC() const
                   virtual Double_t GetAbsWNDC() const
                   virtual Double_t GetAbsXlowNDC() const
                   virtual Double_t GetAbsYlowNDC() const
                   virtual Double_t GetAspectRatio() const
                    virtual Short_t GetBorderMode() const
                    virtual Short_t GetBorderSize() const
                   virtual TCanvas* GetCanvas() const
                      virtual Int_t GetCanvasID() const
                              Int_t GetCrosshair() const
                      virtual Int_t GetEvent() const
                      virtual Int_t GetEventX() const
                      virtual Int_t GetEventY() const
                    virtual TFrame* GetFrame()
                     virtual Bool_t GetGridx() const
                     virtual Bool_t GetGridy() const
                    virtual Color_t GetHighLightColor() const
                   virtual Double_t GetHNDC() const
                     virtual TList* GetListOfExecs() const
                     virtual TList* GetListOfPrimitives() const
                      virtual Int_t GetLogx() const
                      virtual Int_t GetLogy() const
                      virtual Int_t GetLogz() const
                       static Int_t GetMaxPickDistance()
               virtual TVirtualPad* GetMother() const
                virtual const char* GetName() const
                      virtual Int_t GetNumber() const
               virtual TVirtualPad* GetPad(Int_t subpadnumber) const
                      virtual Int_t GetPadPaint() const
                       virtual void GetPadPar(Double_t& xlow, Double_t& ylow, Double_t& xup, Double_t& yup)
                   virtual TObject* GetPadPointer() const
               virtual TVirtualPad* GetPadSave() const
                   virtual Double_t GetPhi() const
                      virtual Int_t GetPixmapID() const
                   virtual TObject* GetPrimitive(const char* name) const
                       virtual void GetRange(Double_t& x1, Double_t& y1, Double_t& x2, Double_t& y2)
                       virtual void GetRangeAxis(Double_t& xmin, Double_t& ymin, Double_t& xmax, Double_t& ymax)
                   virtual TObject* GetSelected() const
               virtual TVirtualPad* GetSelectedPad() const
                   virtual Double_t GetTheta() const
                      virtual Int_t GetTickx() const
                      virtual Int_t GetTicky() const
                virtual const char* GetTitle() const
                   virtual Double_t GetUxmax() const
                   virtual Double_t GetUxmin() const
                   virtual Double_t GetUymax() const
                   virtual Double_t GetUymin() const
                     virtual TView* GetView() const
                virtual TPadView3D* GetView3D() const
          virtual TVirtualViewer3D* GetViewer3D(Option_t* type = "")
               virtual TVirtualPad* GetVirtCanvas() const
                     virtual UInt_t GetWh() const
                   virtual Double_t GetWNDC() const
                     virtual UInt_t GetWw() const
                   virtual Double_t GetX1() const
                   virtual Double_t GetX2() const
                   virtual Double_t GetXlowNDC() const
                   virtual Double_t GetY1() const
                   virtual Double_t GetY2() const
                   virtual Double_t GetYlowNDC() const
                     virtual Bool_t HasCrosshair() const
                     virtual Bool_t HasFixedAspectRatio() const
                    virtual ULong_t Hash() const
                       virtual void HighLight(Color_t col = kRed, Bool_t set = kTRUE)
                    virtual TClass* IsA() const
                     virtual Bool_t IsBatch() const
                     virtual Bool_t IsEditable() const
                     virtual Bool_t IsFolder() const
                     virtual Bool_t IsModified() const
                     virtual Bool_t IsRetained() const
                     virtual Bool_t IsVertical() const
                       virtual void ls(Option_t* option = "") const
                       virtual void Modified(Bool_t flag = 1)
                     virtual Bool_t OpaqueMoving() const
                     virtual Bool_t OpaqueResizing() const
                   virtual Double_t PadtoX(Double_t x) const
                   virtual Double_t PadtoY(Double_t y) const
                       virtual void Paint(Option_t* option = "")
                       virtual void PaintBox(Double_t x1, Double_t y1, Double_t x2, Double_t y2, Option_t* option = "")
                       virtual void PaintFillArea(Int_t n, Float_t* x, Float_t* y, Option_t* option = "")
                       virtual void PaintFillArea(Int_t n, Double_t* x, Double_t* y, Option_t* option = "")
                               void PaintFillAreaHatches(Int_t n, Double_t* x, Double_t* y, Int_t FillStyle)
                               void PaintHatches(Double_t dy, Double_t angle, Int_t nn, Double_t* xx, Double_t* yy)
                       virtual void PaintLine(Double_t x1, Double_t y1, Double_t x2, Double_t y2)
                       virtual void PaintLine3D(Float_t* p1, Float_t* p2)
                       virtual void PaintLine3D(Double_t* p1, Double_t* p2)
                       virtual void PaintLineNDC(Double_t u1, Double_t v1, Double_t u2, Double_t v2)
                       virtual void PaintModified()
                       virtual void PaintPadFrame(Double_t xmin, Double_t ymin, Double_t xmax, Double_t ymax)
                       virtual void PaintPolyLine(Int_t n, Float_t* x, Float_t* y, Option_t* option = "")
                       virtual void PaintPolyLine(Int_t n, Double_t* x, Double_t* y, Option_t* option = "")
                       virtual void PaintPolyLine3D(Int_t n, Double_t* p)
                       virtual void PaintPolyLineNDC(Int_t n, Double_t* x, Double_t* y, Option_t* option = "")
                       virtual void PaintPolyMarker(Int_t n, Float_t* x, Float_t* y, Option_t* option = "")
                       virtual void PaintPolyMarker(Int_t n, Double_t* x, Double_t* y, Option_t* option = "")
                       virtual void PaintText(Double_t x, Double_t y, const char* text)
                       virtual void PaintTextNDC(Double_t u, Double_t v, const char* text)
                      virtual TPad* Pick(Int_t px, Int_t py, TObjLink*& pickobj)
                   virtual Double_t PixeltoX(Int_t px)
                       virtual void PixeltoXY(Int_t xpixel, Int_t ypixel, Double_t& x, Double_t& y)
                   virtual Double_t PixeltoY(Int_t py)
                       virtual void Pop()
                       virtual void Print(const char* filename = "") const
                       virtual void Print(const char* filename, Option_t* option)
                       virtual void Range(Double_t x1, Double_t y1, Double_t x2, Double_t y2)
                       virtual void RangeAxis(Double_t xmin, Double_t ymin, Double_t xmax, Double_t ymax)
                       virtual void RangeAxisChanged()
                       virtual void RangeChanged()
                       virtual void RecursiveRemove(TObject* obj)
                       virtual void RedrawAxis(Option_t* option = "")
                       virtual void ReleaseViewer3D(Option_t* type = "")
                       virtual void ResetToolTip(TObject* tip)
                       virtual void ResetView3D(TPadView3D* view = 0)
                       virtual void ResizePad(Option_t* option = "")
                       virtual void SaveAs(const char* filename = "")
                       virtual void SetAttFillPS(Color_t color, Style_t style)
                       virtual void SetAttLinePS(Color_t color, Style_t style, Width_t lwidth)
                       virtual void SetAttMarkerPS(Color_t color, Style_t style, Size_t msize)
                       virtual void SetAttTextPS(Int_t align, Float_t angle, Color_t color, Style_t font, Float_t tsize)
                       virtual void SetBorderMode(Short_t bordermode)
                       virtual void SetBorderSize(Short_t bordersize)
                       virtual void SetCanvas(TCanvas* c)
                       virtual void SetCanvasSize(UInt_t ww, UInt_t wh)
                       virtual void SetCrosshair(Int_t crhair = 1)
                       virtual void SetCursor(ECursor cursor)
                       virtual void SetDoubleBuffer(Int_t mode = 1)
                       virtual void SetDrawOption(Option_t* option = "")
                       virtual void SetEditable(Bool_t mode = kTRUE)
                       virtual void SetFillStyle(Style_t fstyle)
                       virtual void SetFixedAspectRatio(Bool_t fixed = kTRUE)
                       virtual void SetGrid(Int_t valuex = 1, Int_t valuey = 1)
                       virtual void SetGridx(Int_t value = 1)
                       virtual void SetGridy(Int_t value = 1)
                       virtual void SetLogx(Int_t value = 1)
                       virtual void SetLogy(Int_t value = 1)
                       virtual void SetLogz(Int_t value = 1)
                        static void SetMaxPickDistance(Int_t maxPick = 5)
                       virtual void SetName(const char* name)
                       virtual void SetNumber(Int_t number)
                       virtual void SetPad(const char* name, const char* title, Double_t xlow, Double_t ylow, Double_t xup, Double_t yup, Color_t color = 35, Short_t bordersize = 5, Short_t bordermode = -1)
                       virtual void SetPad(Double_t xlow, Double_t ylow, Double_t xup, Double_t yup)
                       virtual void SetPhi(Double_t phi = 30)
                       virtual void SetSelected(TObject* obj)
                       virtual void SetTheta(Double_t theta = 30)
                       virtual void SetTicks(Int_t valuex = 1, Int_t valuey = 1)
                       virtual void SetTickx(Int_t value = 1)
                       virtual void SetTicky(Int_t value = 1)
                       virtual void SetTitle(const char* title = "")
                       virtual void SetToolTipText(const char* text, Long_t delayms = 1000)
                       virtual void SetVertical(Bool_t vert = kTRUE)
                       virtual void SetView(TView* view)
                       virtual void ShowMembers(TMemberInspector& insp, char* parent)
                       virtual void Streamer(TBuffer& b)
                               void StreamerNVirtual(TBuffer& b)
                       virtual void Update()
                       virtual void UseCurrentStyle()
                      virtual Int_t UtoAbsPixel(Double_t u) const
                      virtual Int_t UtoPixel(Double_t u) const
                      virtual Int_t VtoAbsPixel(Double_t v) const
                      virtual Int_t VtoPixel(Double_t v) const
                   virtual TObject* WaitPrimitive(const char* pname = "", const char* emode = "")
                       virtual void x3d(Option_t* type = "")
                      virtual Int_t XtoAbsPixel(Double_t x) const
                   virtual Double_t XtoPad(Double_t x) const
                      virtual Int_t XtoPixel(Double_t x) const
                       virtual void XYtoAbsPixel(Double_t x, Double_t y, Int_t& xpixel, Int_t& ypixel) const
                       virtual void XYtoPixel(Double_t x, Double_t y, Int_t& xpixel, Int_t& ypixel) const
                      virtual Int_t YtoAbsPixel(Double_t y) const
                   virtual Double_t YtoPad(Double_t y) const
                      virtual Int_t YtoPixel(Double_t y) const

### Data Members

        private:

          TObject* fTip  ! tool tip associated with box

        protected:

                   Double_t fX1                X of lower X coordinate
                   Double_t fY1                Y of lower Y coordinate
                   Double_t fX2                X of upper X coordinate
                   Double_t fY2                Y of upper Y coordinate
                   Double_t fXtoAbsPixelk      Conversion coefficient for X World to absolute pixel
                   Double_t fXtoPixelk         Conversion coefficient for X World to pixel
                   Double_t fXtoPixel          xpixel = fXtoPixelk + fXtoPixel*xworld
                   Double_t fYtoAbsPixelk      Conversion coefficient for Y World to absolute pixel
                   Double_t fYtoPixelk         Conversion coefficient for Y World to pixel
                   Double_t fYtoPixel          ypixel = fYtoPixelk + fYtoPixel*yworld
                   Double_t fUtoAbsPixelk      Conversion coefficient for U NDC to absolute pixel
                   Double_t fUtoPixelk         Conversion coefficient for U NDC to pixel
                   Double_t fUtoPixel          xpixel = fUtoPixelk + fUtoPixel*undc
                   Double_t fVtoAbsPixelk      Conversion coefficient for V NDC to absolute pixel
                   Double_t fVtoPixelk         Conversion coefficient for V NDC to pixel
                   Double_t fVtoPixel          ypixel = fVtoPixelk + fVtoPixel*vndc
                   Double_t fAbsPixeltoXk      Conversion coefficient for absolute pixel to X World
                   Double_t fPixeltoXk         Conversion coefficient for pixel to X World
                   Double_t fPixeltoX          xworld = fPixeltoXk + fPixeltoX*xpixel
                   Double_t fAbsPixeltoYk      Conversion coefficient for absolute pixel to Y World
                   Double_t fPixeltoYk         Conversion coefficient for pixel to Y World
                   Double_t fPixeltoY          yworld = fPixeltoYk + fPixeltoY*ypixel
                   Double_t fXlowNDC           X bottom left corner of pad in NDC [0,1]
                   Double_t fYlowNDC           Y bottom left corner of pad in NDC [0,1]
                   Double_t fWNDC              Width of pad along X in NDC
                   Double_t fHNDC              Height of pad along Y in NDC
                   Double_t fAbsXlowNDC        Absolute X top left corner of pad in NDC [0,1]
                   Double_t fAbsYlowNDC        Absolute Y top left corner of pad in NDC [0,1]
                   Double_t fAbsWNDC           Absolute Width of pad along X in NDC
                   Double_t fAbsHNDC           Absolute Height of pad along Y in NDC
                   Double_t fUxmin             Minimum value on the X axis
                   Double_t fUymin             Minimum value on the Y axis
                   Double_t fUxmax             Maximum value on the X axis
                   Double_t fUymax             Maximum value on the Y axis
                   Double_t fTheta             theta angle to view as lego/surface
                   Double_t fPhi               phi angle   to view as lego/surface
                   Double_t fAspectRatio       ratio of w/h in case of fixed ratio
                      Int_t fPixmapID          ! Off-screen pixmap identifier
                      Int_t fNumber            pad number identifier
                      Int_t fTickx             Set to 1 if tick marks along X
                      Int_t fTicky             Set to 1 if tick marks along Y
                      Int_t fLogx              (=0 if X linear scale, =1 if log scale)
                      Int_t fLogy              (=0 if Y linear scale, =1 if log scale)
                      Int_t fLogz              (=0 if Z linear scale, =1 if log scale)
                      Int_t fPadPaint          Set to 1 while painting the pad
                      Int_t fCrosshair         Crosshair type (0 if no crosshair requested)
                      Int_t fCrosshairPos      Position of crosshair
                    Short_t fBorderSize        pad bordersize in pixels
                    Short_t fBorderMode        Bordermode (-1=down, 0 = no border, 1=up)
                     Bool_t fModified          Set to true when pad is modified
                     Bool_t fGridx             Set to true if grid along X
                     Bool_t fGridy             Set to true if grid along Y
                     Bool_t fAbsCoord          Use absolute coordinates
                     Bool_t fEditable          True if canvas is editable
                     Bool_t fFixedAspectRatio  True if fixed aspect ratio
                      TPad* fMother            ! pointer to mother of the list
                   TCanvas* fCanvas            ! Pointer to mother canvas
                     TList* fPrimitives        ->List of primitives (subpads)
                     TList* fExecs             List of commands to be executed when a pad event occurs
                    TString fName              Pad name
                    TString fTitle             Pad title
                    TFrame* fFrame             ! Pointer to 2-D frame (if one exists)
                     TView* fView              ! Pointer to 3-D view (if one exists)
                   TObject* fPadPointer        ! free pointer
                TPadView3D* fPadView3D         ! 3D View of this TPad
               static Int_t fgMaxPickDistance  Maximum Pick Distance
          TVirtualViewer3D* fViewer3D          ! Current 3D viewer

        public:

          static const enum TPad:: kFraming
          static const enum TPad:: kHori
          static const enum TPad:: kPrintingPS
          static const enum TPad:: kClearAfterCR

## Class Description

      The Pad class is the most important graphics class in the ROOT system.

/* */

      A Pad is contained in a Canvas.
      A Pad may contain other pads (unlimited pad hierarchy).
      A pad is a linked list of primitives of any type (graphics objects,
      histograms, detectors, tracks, etc.).
      Adding a new element into a pad is in general performed by the Draw
      member function of the object classes.
      It is important to realize that the pad is a linked list of references
      to the original object.
      For example, in case of an histogram, the histogram.Draw() operation
      only stores a reference to the histogram object and not a graphical
      representation of this histogram.
      When the mouse is used to change (say the bin content), the bin content
      of the original histogram is changed !!

      The convention used in ROOT is that a Draw operation only adds
      a reference to the object. The effective drawing is performed when
      when the canvas receives a signal to be painted.
      This signal is generally sent when typing carriage return in the
      command input or when a graphical operation has been performed on one
      of the pads of this canvas.
      When a Canvas/Pad is repainted, the member function Paint for all
      objects in the Pad linked list is invoked.

      When the mouse is moved on the Pad, The member function DistancetoPrimitive
      is called for all the elements in the pad. DistancetoPrimitive returns
      the distance in pixels to this object.
      when the object is within the distance window, the member function
      ExecuteEvent is called for this object.
      in ExecuteEvent, move, changes can be performed on the object.
      For examples of DistancetoPrimitive and ExecuteEvent functions,
      see classes TLine::DistancetoPrimitive, TLine::ExecuteEvent
                  TBox::DistancetoPrimitive,  TBox::ExecuteEvent
                  TH1::DistancetoPrimitive,   TH1::ExecuteEvent

      A Pad supports linear and log scales coordinate systems.
      The transformation coefficients are explained in TPad::ResizePad.
      An example of pads hierarchy is shown below:

/* */

TPad()

    *-*-*-*-*-*-*-*-*-*-*Pad default constructor*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*                  =======================

TPad(const char *name, const char *title, Double_t xlow, Double_t ylow, Double_t xup, Double_t yup, Color_t color, Short_t bordersize, Short_t bordermode) : TVirtualPad(name,title,xlow,ylow,xup,yup,color,bordersize,bordermode)

    *-*-*-*-*-*-*-*-*-*-*-*-*-*-*Pad constructor-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*                          ===============
      A pad is a linked list of primitives.
      A pad is contained in a canvas. It may contain other pads.
      A pad has attributes. When a pad is created, the attributes
      defined in the current style are copied to the pad attributes.

      xlow [0,1] is the position of the bottom left point of the pad
                 expressed in the mother pad reference system
      ylow [0,1] is the Y position of this point.
      xup  [0,1] is the x position of the top right point of the pad
                 expressed in the mother pad reference system
      yup  [0,1] is the Y position of this point.

      the bordersize is in pixels
      bordermode = -1 box looks as it is behind the screen
      bordermode = 0  no special effects
      bordermode = 1  box looks as it is in front of the screen

~TPad()

    *-*-*-*-*-*-*-*-*-*-*Pad destructor*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*                  ==============

void AddExec(const char *name, const char*command)

     Add a new TExec object to the list of Execs.
     When an event occurs in the pad (mouse click, etc) the list of CINT commands
     in the list of Execs are executed via TPad::AutoExec.
      When a pad event occurs (mouse move, click, etc) all the commands
      contained in the fExecs list are executed in the order found in the list.
      This facility is activated by default. It can be deactivated by using
      the canvas "Option" menu.
      The following examples of TExec commands are provided in the tutorials:
      macros exec1.C and exec2.C.
      Example1 of use of exec1.C
      ==========================
      Root > TFile f("hsimple.root")
      Root > hpx.Draw()
      Root > c1.AddExec("ex1",".x exec1.C")
       At this point you can use the mouse to click on the contour of
       the histogram hpx. When the mouse is clicked, the bin number and its
       contents are printed.
      Example2 of use of exec1.C
      ==========================
      Root > TFile f("hsimple.root")
      Root > hpxpy.Draw()
      Root > c1.AddExec("ex2",".x exec2.C")
        When moving the mouse in the canvas, a second canvas shows the
        projection along X of the bin corresponding to the Y position
        of the mouse. The resulting histogram is fitted with a gaussian.
        A "dynamic" line shows the current bin position in Y.
        This more elaborated example can be used as a starting point
        to develop more powerful interactive applications exploiting CINT
        as a development engine.

void AutoExec()

     Execute the list of Execs when a pad event occurs.

void Browse(TBrowser *b)

TLegend* BuildLegend(Double_t x1, Double_t y1, Double_t x2, Double_t y2, const char* title)

     Build a legend from the graphical objects in the pad

     A simple method to to build automatically a TLegend from the primitives in
     a TPad. Only those deriving from TAttLine, TAttMarker and TAttFill are
     added, excluding TPave and TFrame derived classes.
     x1, y1, x2, y2 are the Tlegend coordinates.
     title is the legend title. By default it is " ".

TVirtualPad* cd(Int_t subpadnumber)

     Set Current pad.
     When a canvas/pad is divided via TPad::Divide, one can directly
      set the current path to one of the subdivisions.
      See TPad::Divide for the convention to number subpads.
      Returns the new current pad, or 0 in case of failure.
      For example:
        c1.Divide(2,3); // create 6 pads (2 divisions along x, 3 along y).
        To set the current pad to the bottom right pad, do
        c1.cd(6);
      Note1:  c1.cd() is equivalent to c1.cd(0) and sets the current pad
              to c1 itself.
      Note2:  after a statement like c1.cd(6), the global variable gPad
              points to the current pad. One can use gPad to set attributes
              of the current pad.
      Note3:  One can get a pointer to one of the sub-pads of pad with:
              TPad *subpad = (TPad*)pad->GetPad(subpadnumber);

void Clear(Option_t *option)

    *-*-*-*-*-*-*-*-*Delete all pad primitives*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*              =========================

       If the bit kClearAfterCR has been set for this pad, the Clear function
       will execute only after having pressed a CarriageReturn
       Set the bit with mypad->SetBit(TPad::kClearAfterCR)

Int_t Clip(Float_t *x, Float_t *y, Float_t xclipl, Float_t yclipb, Float_t xclipr, Float_t yclipt)

       Clipping routine: Cohen Sutherland algorithm.
     If Clip ==2 the segment is outside the boundary.
     If Clip ==1 the segment has one point outside the boundary.
     If Clip ==0 the segment is inside the boundary.

     _Input parameters:

      x[2], y[2] : Segment coordinates
      xclipl, yclipb, xclipr, yclipt : Clipping boundary

     _Output parameters:

      x[2], y[2] : New segment coordinates

Int_t Clip(Double_t *x, Double_t *y, Double_t xclipl, Double_t yclipb, Double_t xclipr, Double_t yclipt)

       Clipping routine: Cohen Sutherland algorithm.
     If Clip ==2 the segment is outside the boundary.
     If Clip ==1 the segment has one point outside the boundary.
     If Clip ==0 the segment is inside the boundary.

     _Input parameters:

      x[2], y[2] : Segment coordinates
      xclipl, yclipb, xclipr, yclipt : Clipping boundary

     _Output parameters:

      x[2], y[2] : New segment coordinates

Int_t ClippingCode(Double_t x, Double_t y, Double_t xcl1, Double_t ycl1, Double_t xcl2, Double_t ycl2)

       Compute the endpoint codes for TPad::Clip.

void Close(Option_t *)

     Delete all primitives in pad and pad itself.
     Pad cannot be used anymore after this call.
     Emits signal "Closed()".

void CopyPixmap()

    *-*-*-*-*-*-*-*-*Copy the pixmap of the pad to the canvas*-*-*-*-*-*-*
    *-*              ========================================

void CopyPixmaps()

    *-*-*-*-*-*-*-*-*Copy the sub-pixmaps of the pad to the canvas*-*-*-*-*-*-*
    *-*              =============================================

void DeleteExec(const char *name)

     Remove TExec name from the list of Execs.

Int_t DistancetoPrimitive(Int_t px, Int_t py)

    *-*-*-*-*-*-*-*-*-*-*Compute distance from point px,py to a box*-*-*-*-*-*
    *-*                  ==========================================
      Compute the closest distance of approach from point px,py to the
      edges of this pad.
      The distance is computed in pixels units.

void Divide(Int_t nx, Int_t ny, Float_t xmargin, Float_t ymargin, Int_t color)

    *-*-*-*-*-*-*-*-*Automatic pad generation by division*-*-*-*-*-*-*-*-*-*-*
    *-*              ====================================
      The current canvas is divided in nx by ny equal divisions(pads).
      xmargin is the space along x between pads in percent of canvas.
      ymargin is the space along y between pads in percent of canvas.
        (see Note3 below for the special case xmargin <=0 and ymargin <=0)
      color is the color of the new pads. If 0, color is the canvas color.
      Pads are automatically named canvasname_n where n is the division number
      starting from top left pad.
           Example if canvasname=c1 , nx=2, ny=3

        ...............................................................
        .                               .                             .
        .                               .                             .
        .                               .                             .
        .           c1_1                .           c1_2              .
        .                               .                             .
        .                               .                             .
        .                               .                             .
        ...............................................................
        .                               .                             .
        .                               .                             .
        .                               .                             .
        .           c1_3                .           c1_4              .
        .                               .                             .
        .                               .                             .
        .                               .                             .
        ...............................................................
        .                               .                             .
        .                               .                             .
        .                               .                             .
        .           c1_5                .           c1_6              .
        .                               .                             .
        .                               .                             .
        ...............................................................

        Once a pad is divided into subpads, one can set the current pad
        to a subpad with a given division number as illustrated above
        with TPad::cd(subpad_number).
        For example, to set the current pad to c1_4, one can do:
        c1->cd(4)

      Note1:  c1.cd() is equivalent to c1.cd(0) and sets the current pad
              to c1 itself.
      Note2:  after a statement like c1.cd(6), the global variable gPad
              points to the current pad. One can use gPad to set attributes
              of the current pad.
      Note3:  in case xmargin <=0 and ymargin <= 0, there is no space
              between pads. The current pad margins are recomputed to
              optimize the layout.

void Draw(Option_t *option)

    *-*-*-*-*-*-*-*-*Draw Pad in Current pad (re-parent pad if necessary)*-*-*-*
    *-*              ====================================================

void DrawClassObject(const TObject *classobj, Option_t *option)

     Draw class inheritance tree of the class to which obj belongs.
     If a class B inherits from a class A, description of B is drawn
     on the right side of description of A.
     Member functions overridden by B are shown in class A with a blue line
     crossing-out the corresponding member function.
     The following picture is the class inheritance tree of class TPaveLabel:

/* */

void DrawCrosshair()

    Function called to draw a crosshair in the canvas
     Example:
     Root > TFile f("hsimple.root");
     Root > hpxpy.Draw();
     Root > c1.SetCrosshair();
     When moving the mouse in the canvas, a crosshair is drawn

     if the canvas fCrosshair = 1 , the crosshair spans the full canvas
     if the canvas fCrosshair > 1 , the crosshair spans only the pad

TH1F* DrawFrame(Double_t xmin, Double_t ymin, Double_t xmax, Double_t ymax, const char *title)

      Draw a pad frame
      Compute real pad range taking into account all margins
      Use services of TH1F class

void DrawColorTable()

    *-*-*-*-static function to Display Color Table in a pad*-*-*-*-*-*-*
    *-*     ===============================================

void ExecuteEvent(Int_t event, Int_t px, Int_t py)

    *-*-*-*-*-*-*-*-*-*-*Execute action corresponding to one event*-*-*-*
    *-*                  =========================================
      This member function is called when a TPad object is clicked.

      If the mouse is clicked in one of the 4 corners of the pad (PA,PB,PC,PD)
      the pad is resized with the rubber rectangle.

      If the mouse is clicked inside the pad, the pad is moved.

      If the mouse is clicked on the 4 edges (L,R,T,B), the pad is scaled
      parallel to this edge.

        PA                    T                       PB
         +--------------------------------------------+
         |                                            |
         |                                            |
         |                                            |
        L|                  INSIDE                    |R
         |                                            |
         |                                            |
         |                                            |
         |                                            |
         +--------------------------------------------+
        PD                    B                      PC

      Note that this function duplicates on purpose the functionality
      already implemented in TBox::ExecuteEvent.
      If somebody modifies this function, may be similar changes should also
      be applied to TBox::ExecuteEvent.

TObject* FindObject(const char *name) const

TObject* FindObject(const TObject *) const

    not implemented yet

Int_t GetCanvasID() const

Int_t GetEvent() const

Int_t GetEventX() const

Int_t GetEventY() const

TVirtualPad* GetVirtCanvas() const

Color_t GetHighLightColor() const

Int_t GetMaxPickDistance()

    static function (see also TPad::SetMaxPickDistance)

TObject* GetSelected() const

TVirtualPad* GetSelectedPad() const

TVirtualPad* GetPadSave() const

UInt_t GetWh() const

UInt_t GetWw() const

void HideToolTip(Int_t event)

     Hide tool tip depending on the event type. Typically tool tips
     are hidden when event is not a kMouseEnter and not a kMouseMotion
     event.

Bool_t IsBatch() const

Bool_t IsRetained() const

Bool_t OpaqueMoving() const

Bool_t OpaqueResizing() const

void SetBatch(Bool_t batch)

void SetCanvasSize(UInt_t ww, UInt_t wh)

void SetCursor(ECursor cursor)

void SetDoubleBuffer(Int_t mode)

void SetSelected(TObject *obj)

void Update()

TFrame* GetFrame()

TObject* GetPrimitive(const char *name) const

TVirtualPad* GetPad(Int_t subpadnumber) const

      Get a pointer to subpadnumber of this pad

void GetPadPar(Double_t &xlow, Double_t &ylow, Double_t &xup, Double_t &yup)

    *-*-*-*-*-*-*-*Return lower and upper bounds of the pad in NDC coordinates
    *-*            ===========================================================

void GetRange(Double_t &x1, Double_t &y1, Double_t &x2, Double_t &y2)

    *-*-*-*-*-*-*-*Return pad world coordinates range*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*            ==================================

void GetRangeAxis(Double_t &xmin, Double_t &ymin, Double_t &xmax, Double_t &ymax)

    *-*-*-*-*-*-*-*Return pad axis coordinates range*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*            ==================================

void HighLight(Color_t color, Bool_t set)

void ls(Option_t *option) const

    *-*-*-*-*-*-*-*-*-*List all primitives in pad*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*                ==========================

Double_t PadtoX(Double_t x) const

Double_t PadtoY(Double_t y) const

Double_t XtoPad(Double_t x) const

Double_t YtoPad(Double_t y) const

void Paint(Option_t * /*option*/)

    *-*-*-*-*-*-*-*-*-*Paint all primitives in pad*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*                ===========================

void PaintBorder(Color_t color, Bool_t tops)

    *-*-*-*-*-*-*-*-*-*Paint the pad border*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*                ====================

void PaintBorderPS(Double_t xl,Double_t yl,Double_t xt,Double_t yt,Int_t bmode,Int_t bsize,Int_t dark,Int_t light)

    *-*-*-*-*-*-*-*Paint a frame border with Postscript*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*            ====================================

void PaintDate()

     Paint the current date and time if the option date is on

void PaintPadFrame(Double_t xmin, Double_t ymin, Double_t xmax, Double_t ymax)

    *-*-*-*-*-*-*-*-*-*Paint histogram/graph frame*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*                ===========================

void PaintModified()

    *-*-*-*-*-*-*Traverse pad hierarchy and (re)paint only modified pads*-*-*-*
    *-*          =======================================================

void PaintBox(Double_t x1, Double_t y1, Double_t x2, Double_t y2, Option_t *option)

    *-*-*-*-*-*-*-*-*Paint box in CurrentPad World coordinates*-*-*-*-*-*-*-*-*-*
    *-*              =========================================
     if option[0] = 's' the box is forced to be paint with style=0

void CopyBackgroundPixmaps(TPad *start, TPad *stop, Int_t x, Int_t y)

     Copy pixmaps of pads laying below pad "stop" into pad "stop". This
     gives the effect of pad "stop" being transparent.

void CopyBackgroundPixmap(Int_t x, Int_t y)

     Copy pixmap of this pad as background of the current pad.

void PaintFillArea(Int_t nn, Float_t *xx, Float_t *yy, Option_t *)

    *-*-*-*-*-*-*-*-*Paint fill area in CurrentPad World coordinates*-*-*-*-*-*-*
    *-*              ===============================================

void PaintFillArea(Int_t nn, Double_t *xx, Double_t *yy, Option_t *)

    *-*-*-*-*-*-*-*-*Paint fill area in CurrentPad World coordinates*-*-*-*-*-*-*
    *-*              ===============================================

void PaintFillAreaHatches(Int_t nn, Double_t *xx, Double_t *yy, Int_t FillStyle)

       This function paints hatched fill area arcording to the FillStyle value
     The convention for the Hatch is the following:

                FillStyle = 3ijk

        i (1-9) : specify the space between each hatch
                  1 = minimum  9 = maximum
                  the final spaing is i*GetHatchesSpacing() the hatches spacing
                  is set by SetHatchesSpacing()

        j (0-9) : specify angle between 0 and 90 degrees

                  0 = 0
                  1 = 10
                  2 = 20
                  3 = 30
                  4 = 45
                  5 = Not drawn
                  6 = 60
                  7 = 70
                  8 = 80
                  9 = 90

        k (0-9) : specify angle between 90 and 180 degrees
                  0 = 180
                  1 = 170
                  2 = 160
                  3 = 150
                  4 = 135
                  5 = Not drawn
                  6 = 120
                  7 = 110
                  8 = 100
                  9 = 90

void PaintHatches(Double_t dy, Double_t angle, Int_t nn, Double_t *xx, Double_t *yy)

     This routine draw hatches inclined with the
     angle "angle" and spaced of "dy" in normalized device
     coordinates in the surface defined by n,xx,yy.

void PaintLine(Double_t x1, Double_t y1, Double_t x2, Double_t y2)

    *-*-*-*-*-*-*-*-*Paint line in CurrentPad World coordinates*-*-*-*-*-*-*-*
    *-*              ==========================================

void PaintLineNDC(Double_t u1, Double_t v1,Double_t u2, Double_t v2)

    *-*-*-*-*-*-*-*Draw a line with coordinates in NDC*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*            ===================================

void PaintLine3D(Float_t *p1, Float_t *p2)

    *-*-*-*-*-*-*-*-*Paint 3-D line in the CurrentPad*-*-*-*-*-*-*-*-*-*-*
    *-*              ================================

void PaintLine3D(Double_t *p1, Double_t *p2)

    *-*-*-*-*-*-*-*-*Paint 3-D line in the CurrentPad*-*-*-*-*-*-*-*-*-*-*
    *-*              ================================

void PaintPolyLine(Int_t n, Float_t *x, Float_t *y, Option_t *)

    *-*-*-*-*-*-*-*-*Paint polyline in CurrentPad World coordinates*-*-*-*-*-*-*
    *-*              ==============================================

void PaintPolyLine(Int_t n, Double_t *x, Double_t *y, Option_t *option)

    *-*-*-*-*-*-*-*-*Paint polyline in CurrentPad World coordinates*-*-*-*-*-*-*
    *-*              ==============================================
      If option[0] == 'C' no clipping

void PaintPolyLineNDC(Int_t n, Double_t *x, Double_t *y, Option_t *)

    *-*-*-*-*-*-*-*-*Paint polyline in CurrentPad NDC coordinates*-*-*-*-*-*-*
    *-*              ============================================

void PaintPolyLine3D(Int_t n, Double_t *p)

    *-*-*-*-*-*-*-*-*Paint 3-D polyline in the CurrentPad*-*-*-*-*-*-*-*-*-*-*
    *-*              ====================================

void PaintPolyMarker(Int_t nn, Float_t *x, Float_t *y, Option_t *)

    *-*-*-*-*-*-*-*-*Paint polymarker in CurrentPad World coordinates*-*-*-*-*-*
    *-*              ================================================

void PaintPolyMarker(Int_t nn, Double_t *x, Double_t *y, Option_t *)

    *-*-*-*-*-*-*-*-*Paint polymarker in CurrentPad World coordinates*-*-*-*-*-*
    *-*              ================================================

void PaintText(Double_t x, Double_t y, const char *text)

    *-*-*-*-*-*-*-*-*Paint text in CurrentPad World coordinates*-*-*-*-*-*-*-*
    *-*              ==========================================

void PaintTextNDC(Double_t u, Double_t v, const char *text)

    *-*-*-*-*-*-*-*-*Paint text in CurrentPad NDC coordinates*-*-*-*-*-*-*-*
    *-*              ========================================

TPad* Pick(Int_t px, Int_t py, TObjLink *&pickobj)

    *-*-*-*-*-*-*-*-*Search for an object at pixel position px,py*-*-*-*-*-*-*
    *-*              ============================================
      Check if point is in this pad.
      If yes, check if it is in one of the subpads
      If found in the pad, compute closest distance of approach
      to each primitive.
      If one distance of approach is found to be within the limit Distancemaximum
      the corresponding primitive is selected and the routine returns.

void Pop()

    *-*-*-*-*-*-*-*-*-*-*Pop pad to the top of the stack*-*-*-*-*-*-*-*-*-*-*-*
    *-*                  ===============================

void Print(const char *filename) const

      Save Pad contents on a  file in various formats
      ===============================================

       if filename is "", the file produced is padname.ps
       if filename starts with a dot, the padname is added in front
       if filename contains .eps, an Encapsulated Postscript file is produced
       if filename contains .gif, a GIF file is produced
       if filename contains .C or .cxx, a C++ macro file is produced
       if filename contains .root, a Root file is produced
       if filename contains .xml,  a XML file is produced

      See comments in TPad::SaveAs or the TPad::Print function below

void Print(const char *filenam, Option_t *option)

    *-*-*-*-*Save Pad contents on a file in various formats*-*-*-*-*-*
    *-*      ==============================================

       if option  =  0   - as "ps"
                   "ps"  - Postscript file is produced (see special cases below)
              "Portrait" - Postscript file is produced (Portrait)
             "Landscape" - Postscript file is produced (Landscape)
                   "eps" - an Encapsulated Postscript file is produced
               "Preview" - an Encapsulated Postscript file with preview is produced.
                   "pdf" - a PDF file is produced
                   "svg" - a SVG file is produced
                   "gif" - a GIF file is produced
                   "xpm" - a XPM file is produced
                   "png" - a PNG file is produced
                   "jpg" - a JPEG file is produced
                   "tiff" - a TIFF file is produced
                   "cxx" - a C++ macro file is produced
                   "xml" - a XML file
                  "root" - a ROOT binary file

         filename = 0 - filename  is defined by the GetName and its
                        extension is defined with the option

       When Postscript output is selected (ps, eps), the pad is saved
       to filename.ps or filename.eps. The aspect ratio of the pad is preserved
       on the Postscript file. When the "ps" option is selected, the Postscript
       page will be landscape format if the pad is in landscape format, otherwise
       portrait format is selected.
       The physical size of the Postscript page is the one selected in the
       current style. This size can be modified via TStyle::SetPaperSize.
       Examples:
            gStyle->SetPaperSize(kA4);  //default
            gStyle->SetPaperSize(kUSLetter);
         where kA4 and kUSLetter are defined in the enum EPaperSize in TStyle.h
        An alternative is to call:
            gStyle->SetPaperSize(20,26);  same as kA4
     or     gStyle->SetPaperSize(20,24);  same as kUSLetter
       The above numbers take into account some margins and are in centimeters.

      The "Preview" option allows to generate a preview (in the TIFF format) within
      the Encapsulated Postscript file. This preview can be used by programs like
      MSWord to visualize the picture on screen. The "Preview" option relies on the
      epstool command (http://www.cs.wisc.edu/~ghost/gsview/epstool.htm).
      Example:
         canvas->Print("example.eps","Preview");

      To generate a Postscript file containing more than one picture, see
      class TPostScript.

       Writing several canvases to the same Postscript file
       ----------------------------------------------------
     if the Postscript file name finishes with "(", the file is not closed
     if the Postscript file name finishes with ")" and the file has been opened
        with "(", the file is closed. Example:
     {
        TCanvas c1("c1");
        h1.Draw();
        c1.Print("c1.ps("); //write canvas and keep the ps file open
        h2.Draw();
        c1.Print("c1.ps"); canvas is added to "c1.ps"
        h3.Draw();
        c1.Print("c1.ps)"); canvas is added to "c1.ps" and ps file is closed
     }

      Note that the following sequence writes the canvas to "c1.ps" and closes the ps file.:
        TCanvas c1("c1");
        h1.Draw();
        c1.Print("c1.ps");

      The TCanvas::Print("file.ps(") mechanism is very useful, but it can be
      a little inconvenient to have the action of opening/closing a file
      being atomic with printing a page.  Particularly if pages are being
      generated in some loop one needs to detect the special cases of first
      and last page and then munge the argument to Print() accordingly.

      The "[" and "]" can be used instead of "(" and ")".  Example:

        c1.Print("file.ps[");   // No actual print, just open file.ps
        for (int i=0; i<10; ++i) {
          // fill canvas for context i
          // ...

          c1.Print("file.ps");  // actually print canvas to file
        }// end loop
        c1.Print("file.ps]");   // No actual print, just close.

void Range(Double_t x1, Double_t y1, Double_t x2, Double_t y2)

     Set world coordinate system for the pad.
     Emits signal "RangeChanged()", in the slot get the range
     via GetRange().

void RangeAxis(Double_t xmin, Double_t ymin, Double_t xmax, Double_t ymax)

     Set axis coordinate system for the pad.
     The axis coordinate system is a subset of the world coordinate system
     xmin,ymin is the origin of the current coordinate system,
     xmax is the end of the X axis, ymax is the end of the Y axis.
     By default a margin of 10 per cent is left on all sides of the pad
     Emits signal "RangeAxisChanged()", in the slot get the axis range
     via GetRangeAxis().

void RecursiveRemove(TObject *obj)

    *-*-*-*-*-*-*-*Recursively remove object from a pad and its subpads*-*-*-*-*
    *-*            ====================================================

void RedrawAxis(Option_t *option)

      Redraw the frame axis
      Redrawing axis may be necessary in case of superimposed histograms
      when one or more histograms have a fill color
      Instead of calling this function, it may be more convenient
      to call directly h1->Draw("sameaxis") where h1 is the pointer
      to the first histogram drawn in the pad.

      By default, if the pad has the options gridx or/and gridy activated,
      the grid is not drawn by this function.
      if option="g" is specified, this will force the drawing of the grid
      on top of the picture

     get first histogram in the list of primitives

void ResizePad(Option_t *option)

    *-*-*-*-*-*-*-*-*-*-*Compute pad conversion coefficients*-*-*-*-*-*-*-*-*
    *-*                  ===================================

       Conversion from x to px & y to py
       =================================

           x - xmin     px - pxlow              xrange  = xmax-xmin
           --------  =  ----------      with
            xrange        pxrange               pxrange = pxmax-pxmin

                   pxrange(x-xmin)
       ==>  px =   ---------------  + pxlow   = fXtoPixelk + fXtoPixel * x
                        xrange

       ==>  fXtoPixelk = pxlow - pxrange*xmin/xrange
            fXtoPixel  = pxrange/xrange
               where  pxlow   = fAbsXlowNDC*fCw
                      pxrange = fAbsWNDC*fCw

           y - ymin     py - pylow              yrange  = ymax-ymin
           --------  =  ----------      with
            yrange        pyrange               pyrange = pymax-pymin

                   pyrange(y-ymin)
       ==>  py =   ---------------  + pylow   = fYtoPixelk + fYtoPixel * y
                        yrange

       ==>  fYtoPixelk = pylow - pyrange*ymin/yrange
            fYtoPixel  = pyrange/yrange
               where  pylow   = (1-fAbsYlowNDC)*fCh
                      pyrange = -fAbsHNDC*fCh

    -  Conversion from px to x & py to y
       =================================

                 xrange(px-pxlow)
       ==>  x =  ----------------  + xmin  = fPixeltoXk + fPixeltoX * px
                     pxrange
    -
       ==>  fPixeltoXk = xmin - pxlow*xrange/pxrange
            fPixeltoX  = xrange/pxrange

                 yrange(py-pylow)
       ==>  y =  ----------------  + ymin  = fPixeltoYk + fPixeltoY * py
                     pyrange
    -
       ==>  fPixeltoYk = ymin - pylow*yrange/pyrange
            fPixeltoY  = yrange/pyrange

    -----------------------------------------------------------------------

      Computation of the coefficients in case of LOG scales
    - =====================================================

       A, Conversion from pixel coordinates to world coordinates

           Log(x) - Log(xmin)      Log(x/xmin)       px - pxlow
      u = --------------------- =  -------------  =  -----------
          Log(xmax) - Log(xmin)    Log(xmax/xmin)     pxrange

      ==> Log(x/xmin) = u*Log(xmax/xmin)
          x = xmin*exp(u*Log(xmax/xmin)
       Let alfa = Log(xmax/xmin)/fAbsWNDC

          x = xmin*exp(-alfa*pxlow) + exp(alfa*px)
          x = fPixeltoXk*exp(fPixeltoX*px)
      ==> fPixeltoXk = xmin*exp(-alfa*pxlow)
          fPixeltoX  = alfa

           Log(y) - Log(ymin)      Log(y/ymin)       pylow - py
      v = --------------------- =  -------------  =  -----------
          Log(ymax) - Log(ymin)    Log(ymax/ymin)     pyrange

       Let beta = Log(ymax/ymin)/pyrange
          Log(y/ymin) = beta*pylow - beta*py
          y/ymin = exp(beta*pylow - beta*py)
          y = ymin*exp(beta*pylow)*exp(-beta*py)
      ==> y = fPixeltoYk*exp(fPixeltoY*py)
          fPixeltoYk = ymin*exp(beta*pylow)
          fPixeltoY  = -beta

    -  B, Conversion from World coordinates to pixel coordinates

      px = pxlow + u*pxrange
         = pxlow + Log(x/xmin)/alfa
         = pxlow -Log(xmin)/alfa  + Log(x)/alfa
         = fXtoPixelk + fXtoPixel*Log(x)
      ==> fXtoPixelk = pxlow -Log(xmin)/alfa
      ==> fXtoPixel  = 1/alfa

      py = pylow - Log(y/ymin)/beta
         = fYtoPixelk + fYtoPixel*Log(y)
      ==> fYtoPixelk = pylow - Log(ymin)/beta
          fYtoPixel  = 1/beta

void SaveAs(const char *filename)

    *-*-*-*-*Save Pad contents on a  file in various formats*-*-*-*-*-*
    *-*      ===============================================

       if filename is "", the file produced is padname.ps
       if filename starts with a dot, the padname is added in front
       if filename contains .eps, an Encapsulated Postscript file is produced
       if filename contains .pdf, a PDF file is produced
       if filename contains .svg, a SVG file is produced
       if filename contains .gif, a GIF file is produced
       if filename contains  .xpm, a XPM file is produced
       if filename contains . png, a PNG file is produced
       if filename contains . jpg, a JPEG file is produced
       if filename contains . tiff, a TIFF file is produced
       if filename contains .C or .cxx, a C++ macro file is produced
       if filename contains .root, a Root file is produced
       if filename contains .xml, a XML file is produced

       See comments in TPad::Print for the Postscript formats

void SavePrimitive(ofstream &out, Option_t *)

    *-*-*-*-*-*Save primitives in this pad on the C++ source file out*-*-*-*-*-*
    *-*        ======================================================

void SetFixedAspectRatio(Bool_t fixed)

     Fix pad aspect ratio to current value if fixed is true.

void SetEditable(Bool_t mode)

     Set pad editable yes/no
     If a pad is not editable:
     - one cannot modify the pad and its objects via the mouse.
     - one cannot add new objects to the pad

void SetFillStyle(Style_t fstyle)

     Overrride TAttFill::FillStyle for TPad because we want to handle style=0
     as style 4000.

void SetLogx(Int_t value)

    *-*-*-*-*-*-*-*-*Set Lin/Log scale for X
    *-*              ========================

void SetLogy(Int_t value)

    *-*-*-*-*-*-*-*-*Set Lin/Log scale for Y
    *-*              ========================

void SetLogz(Int_t value)

    *-*-*-*-*-*-*-*-*Set Lin/Log scale for Z
    *-*              ========================

void SetPad(Double_t xlow, Double_t ylow, Double_t xup, Double_t yup)

     Set canvas range for pad and resize the pad. If the aspect ratio
     was fixed before the call it will be un-fixed.

void SetPad(const char *name, const char *title, Double_t xlow, Double_t ylow, Double_t xup, Double_t yup, Color_t color, Short_t bordersize, Short_t bordermode)

    *-*-*-*-*-*-*-*-*Set all pad parameters*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*              ======================
    if (!IsEditable()) return;

void SetAttFillPS(Color_t color, Style_t style)

    *-*-*-*-*-*-*-*-*Set postscript fill area attributes*-*-*-*-*-*-*-*-*-*-*
    *-*              ===================================

void SetAttLinePS(Color_t color, Style_t style, Width_t lwidth)

    *-*-*-*-*-*-*-*-*Set postscript line attributes*-*-*-*-*-*-*-*-*-*-*
    *-*              ==============================

void SetAttMarkerPS(Color_t color, Style_t style, Size_t msize)

    *-*-*-*-*-*-*-*-*Set postscript marker attributes*-*-*-*-*-*-*-*-*-*-*
    *-*              ================================

void SetAttTextPS(Int_t align, Float_t angle, Color_t color, Style_t font, Float_t tsize)

     Set postscript text attributes.

Bool_t HasCrosshair() const

     Return kTRUE if the crosshair has been activated (via SetCrosshair).

Int_t GetCrosshair() const

     Return the crosshair type (from the mother canvas)
     crosshair type = 0 means no crosshair.

void SetCrosshair(Int_t crhair)

     Set crosshair active/inactive.
     If crhair != 0, a crosshair will be drawn in the pad and its subpads.
     If the canvas crhair = 1 , the crosshair spans the full canvas.
     If the canvas crhair > 1 , the crosshair spans only the pad.

void SetMaxPickDistance(Int_t maxPick)

     static function to set the maximum Pick Distance fgMaxPickDistance
     This parameter is used in TPad::Pick to select an object if
     its DistancetoPrimitive returns a value < fgMaxPickDistance
     The default value is 5 pixels. Setting a smaller value will make
     picking more precise but also more difficult

void SetToolTipText(const char *text, Long_t delayms)

     Set tool tip text associated with this pad. The delay is in
     milliseconds (minimum 250). To remove tool tip call method with
     text = 0.

void SetVertical(Bool_t vert)

     Set pad vertical (default) or horizontal

void Streamer(TBuffer &b)

    *-*-*-*-*-*-*-*-*Stream a class object*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    *-*              =========================================

void UseCurrentStyle()

    *-*-*-*-*-*Force a copy of current style for all objects in pad*-*-*-*-*
    *-*        ====================================================

TObject* WaitPrimitive(const char *pname, const char *emode)

     Loop and sleep until a primitive with name=pname
     is found in the pad.
     If emode is given, the editor is automatically set to emode, ie
     it is not required to have the editor control bar.
     The possible values for emode are:
      emode = "" (default). User will select the mode via the editor bar
            = "Arc", "Line", "Arrow", "Button", "Diamond", "Ellipse",
            = "Pad","pave", "PaveLabel","PaveText", "PavesText",
            = "PolyLine", "CurlyLine", "CurlyArc", "Text", "Marker", "CutG"
     if emode is specified and it is not valid, "PolyLine" is assumed.
     if emode is not specified or ="", an attempt is to use pname[1...]
     for example if pname="TArc", emode="Arc" will be assumed.
     When this function is called within a macro, the macro execution
     is suspended until a primitive corresponding to the arguments
     is found in the pad.
     If CRTL/C is typed in the pad, the function returns 0.
     While this function is executing, one can use the mouse, interact
     with the graphics pads, use the Inspector, Browser, TreeViewer, etc.
     Examples:
       c1.WaitPrimitive();      // Return the first created primitive
                                // whatever it is.
                                // If a double-click with the mouse is executed
                                // in the pad or any key pressed, the function
                                // returns 0.
       c1.WaitPrimitive("ggg"); // Set the editor in mode "PolyLine/Graph"
                                // Create a polyline, then using the context
                                // menu item "SetName", change the name
                                // of the created TGraph to "ggg"
       c1.WaitPrimitive("TArc");// Set the editor in mode "Arc". Returns
                                // as soon as a TArc object is created.
       c1.WaitPrimitive("lat","Text"); // Set the editor in Text/Latex mode.
                                // Create a text object, then Set its name to "lat"

     The following macro waits for 10 primitives of any type to be created.
    {
       TCanvas c1("c1");
       TObject *obj;
       for (Int_t i=0;i<10;i++) {
          obj = gPad->WaitPrimitive();
          if (!obj) break;
          printf("Loop i=%d, found objIsA=%s, name=%s\n",
             i,obj->ClassName(),obj->GetName());
       }
    }

TObject* CreateToolTip(const TBox *box, const char *text, Long_t delayms)

     Create a tool tip and return its pointer.

void DeleteToolTip(TObject *tip)

     Delete tool tip object.

void ResetToolTip(TObject *tip)

     Reset tool tip, i.e. within time specified in CreateToolTip the
     tool tip will pop up.

void CloseToolTip(TObject *tip)

     Hide tool tip.

void x3d(Option_t *type)

TVirtualViewer3D* GetViewer3D(Option_t *type)

     No type specified?

void ReleaseViewer3D(Option_t * /*type*/ )

     Release current (external) viewer
     TODO: By type

### Inline Functions

                    void DestroyExternalViewer3D()
                   TPad& operator=(const TPad& rhs)
                    TPad TPad(const char* name, const char* title, Double_t xlow, Double_t ylow, Double_t xup, Double_t yup, Color_t color = -1, Short_t bordersize = -1, Short_t bordermode = -2)
                    void AbsCoordinates(Bool_t set)
                Double_t AbsPixeltoX(Int_t px)
                Double_t AbsPixeltoY(Int_t py)
                    void AbsPixeltoXY(Int_t xpixel, Int_t ypixel, Double_t& x, Double_t& y)
                    void Closed()
                 Short_t GetBorderMode() const
                 Short_t GetBorderSize() const
                Double_t GetXlowNDC() const
                Double_t GetYlowNDC() const
                Double_t GetWNDC() const
                Double_t GetHNDC() const
                Double_t GetAbsXlowNDC() const
                Double_t GetAbsYlowNDC() const
                Double_t GetAbsWNDC() const
                Double_t GetAbsHNDC() const
                Double_t GetAspectRatio() const
                Double_t GetPhi() const
                Double_t GetTheta() const
                Double_t GetUxmin() const
                Double_t GetUymin() const
                Double_t GetUxmax() const
                Double_t GetUymax() const
                  Bool_t GetGridx() const
                  Bool_t GetGridy() const
                   Int_t GetNumber() const
                   Int_t GetTickx() const
                   Int_t GetTicky() const
                Double_t GetX1() const
                Double_t GetX2() const
                Double_t GetY1() const
                Double_t GetY2() const
                  TList* GetListOfPrimitives() const
                  TList* GetListOfExecs() const
                TObject* GetPadPointer() const
                  TView* GetView() const
             TPadView3D* GetView3D() const
                   Int_t GetLogx() const
                   Int_t GetLogy() const
                   Int_t GetLogz() const
            TVirtualPad* GetMother() const
             const char* GetName() const
             const char* GetTitle() const
                TCanvas* GetCanvas() const
                   Int_t GetPadPaint() const
                   Int_t GetPixmapID() const
                 ULong_t Hash() const
                  Bool_t HasFixedAspectRatio() const
                  Bool_t IsEditable() const
                  Bool_t IsFolder() const
                  Bool_t IsModified() const
                  Bool_t IsVertical() const
                    void Modified(Bool_t flag = 1)
                Double_t PixeltoX(Int_t px)
                Double_t PixeltoY(Int_t py)
                    void PixeltoXY(Int_t xpixel, Int_t ypixel, Double_t& x, Double_t& y)
                    void RangeChanged()
                    void RangeAxisChanged()
                    void ResetView3D(TPadView3D* view = 0)
                    void SetBorderMode(Short_t bordermode)
                    void SetBorderSize(Short_t bordersize)
                    void SetCanvas(TCanvas* c)
                    void SetDrawOption(Option_t* option = "")
                    void SetGrid(Int_t valuex = 1, Int_t valuey = 1)
                    void SetGridx(Int_t value = 1)
                    void SetGridy(Int_t value = 1)
                    void SetNumber(Int_t number)
                    void SetName(const char* name)
                    void SetTicks(Int_t valuex = 1, Int_t valuey = 1)
                    void SetTickx(Int_t value = 1)
                    void SetTicky(Int_t value = 1)
                    void SetTitle(const char* title = "")
                    void SetTheta(Double_t theta = 30)
                    void SetPhi(Double_t phi = 30)
                    void SetView(TView* view)
                   Int_t UtoAbsPixel(Double_t u) const
                   Int_t VtoAbsPixel(Double_t v) const
                   Int_t UtoPixel(Double_t u) const
                   Int_t VtoPixel(Double_t v) const
                   Int_t XtoAbsPixel(Double_t x) const
                   Int_t YtoAbsPixel(Double_t y) const
                   Int_t XtoPixel(Double_t x) const
                   Int_t YtoPixel(Double_t y) const
                    void XYtoAbsPixel(Double_t x, Double_t y, Int_t& xpixel, Int_t& ypixel) const
                    void XYtoPixel(Double_t x, Double_t y, Int_t& xpixel, Int_t& ypixel) const
                 TClass* Class()
                 TClass* IsA() const
                    void ShowMembers(TMemberInspector& insp, char* parent)
                    void StreamerNVirtual(TBuffer& b)

Author: Rene Brun 12/12/94
Last update: root/gpad:$Name: $:$Id: TPad.cxx,v 1.185 2005/06/24 12:27:29 brun Exp $
Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *