TGraphPainter.cxx

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// @(#)root/histpainter:$Id: TGraphPainter.cxx,v 1.00
// Author: Olivier Couet
 
/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/
 
#include "TROOT.h"
#include "TGraphPainter.h"
#include "TMath.h"
#include "TGraph.h"
#include "TPolyLine.h"
#include "TPolyMarker.h"
#include "TCanvas.h"
#include "TStyle.h"
#include "TH1.h"
#include "TH2.h"
#include "TF1.h"
#include "TPaveStats.h"
#include "TGaxis.h"
#include "TGraphAsymmErrors.h"
#include "TGraphMultiErrors.h"
#include "TGraphBentErrors.h"
#include "TGraphPolargram.h"
#include "TGraphPolar.h"
#include "TGraphQQ.h"
#include "TScatter.h"
#include "TPaletteAxis.h"
#include "TLatex.h"
#include "TArrow.h"
#include "TFrame.h"
#include "TMarker.h"
#include "TVirtualPadEditor.h"
#include "TVirtualX.h"
#include "TRegexp.h"
#include "strlcpy.h"
#include "snprintf.h"
#include <memory>
 
Int_t TGraphPainter::fgMaxPointsPerLine = 50;
 
static Int_t    gHighlightPoint  = -1;         // highlight point of graph
static TGraph  *gHighlightGraph  = nullptr;    // pointer to graph with highlight point
static std::unique_ptr<TMarker> gHighlightMarker;    // highlight marker
 
ClassImp(TGraphPainter);
 
 
////////////////////////////////////////////////////////////////////////////////
 
/*! \class TGraphPainter
    \ingroup Histpainter
    \brief The graph painter class. Implements all graphs' drawing's options.
 
- [Introduction](\ref GrP0)
- [Graphs' plotting options](\ref GrP1)
- [Exclusion graphs](\ref GrP2)
- [Graphs with error bars](\ref GrP3)
   - [TGraphErrors](\ref GrP3a)
   - [TGraphAsymmErrors](\ref GrP3b)
   - [TGraphBentErrors](\ref GrP3c)
   - [TGraphMultiErrors](\ref GrP3d)
- [TGraphPolar options](\ref GrP4)
- [Colors automatically picked in palette](\ref GrP5)
- [Reverse graphs' axis](\ref GrP6)
- [Graphs in logarithmic scale](\ref GrP7)
- [Highlight mode for graph](\ref GrP8)
 
 
\anchor GrP0
### Introduction
 
Graphs are drawn via the painter `TGraphPainter` class. This class
implements techniques needed to display the various kind of
graphs i.e.: `TGraph`, `TGraphErrors`, `TGraphBentErrors` and `TGraphAsymmErrors`.
 
To draw a graph `graph` it's enough to do:
 
    graph->Draw("AL");
 
The option `AL` in the `Draw()` method means:
 
1. The axis should be drawn (option `A`),
2. The graph should be drawn as a simple line (option `L`).
 
 By default a graph is drawn in the current pad in the current coordinate system.
To define a suitable coordinate system and draw the axis the option
`A` must be specified.
 
`TGraphPainter` offers many options to paint the various kind of graphs.
 
It is separated from the graph classes so that one can have graphs without the
graphics overhead, for example in a batch program.
 
When a displayed graph is modified, there is no need to call `Draw()` again; the
image will be refreshed the next time the pad will be updated. A pad is updated
after one of these three actions:
 
1.  a carriage return on the ROOT command line,
2.  a click inside the pad,
3.  a call to `TPad::Update`.
 
\anchor GrP1
### Graphs' plotting options
Graphs can be drawn with the following options:
 
| Option   | Description                                                       |
|----------|-------------------------------------------------------------------|
| "A"      | Produce a new plot with Axis around the graph |
| "I"      | Combine with option 'A' it draws invisible axis |
| "L"      | A simple polyline is drawn |
| "F"      | A fill area is drawn ('CF' draw a smoothed fill area) |
| "C"      | A smooth Curve is drawn |
| "*"      | A Star is plotted at each point |
| "P"      | The current marker is plotted at each point |
| "B"      | A Bar chart is drawn |
| "1"      | When a graph is drawn as a bar chart, this option makes the bars start from the bottom of the pad. By default they start at 0. |
| "X+"     | The X-axis is drawn on the top side of the plot. |
| "Y+"     | The Y-axis is drawn on the right side of the plot. |
| "PFC"    | Palette Fill Color: graph's fill color is taken in the current palette. |
| "PLC"    | Palette Line Color: graph's line color is taken in the current palette. |
| "PMC"    | Palette Marker Color: graph's marker color is taken in the current palette. |
| "RX"     | Reverse the X axis. |
| "RY"     | Reverse the Y axis. |
 
Drawing options can be combined. In the following example the graph
is drawn as a smooth curve (option "C") with markers (option "P") and
with axes (option "A").
 
Begin_Macro(source)
{
   auto c1 = new TCanvas("c1","c1",200,10,600,400);
 
   c1->SetFillColor(42);
   c1->SetGrid();
 
   const Int_t n = 20;
   Double_t x[n], y[n];
   for (Int_t i=0;i<n;i++) {
      x[i] = i*0.1;
      y[i] = 10*sin(x[i]+0.2);
   }
   gr = new TGraph(n,x,y);
   gr->SetLineColor(2);
   gr->SetLineWidth(4);
   gr->SetMarkerColor(4);
   gr->SetMarkerSize(1.5);
   gr->SetMarkerStyle(21);
   gr->SetTitle("Option ACP example");
   gr->GetXaxis()->SetTitle("X title");
   gr->GetYaxis()->SetTitle("Y title");
   gr->Draw("ACP");
 
   // TCanvas::Update() draws the frame, after which one can change it
   c1->Update();
   c1->GetFrame()->SetFillColor(21);
   c1->GetFrame()->SetBorderSize(12);
   c1->Modified();
}
End_Macro
 
The following macro shows the option "B" usage. It can be combined with the
option "1".
 
The bar width is equal to:
 
    bar_width  = 0.5*delta*gStyle->GetBarWidth();
 
Where `delta` is equal to the X maximal value minus the X minimal value divided by the
number of points in the graph.
 
Begin_Macro(source)
{
   auto c47 = new TCanvas("c47","c47",200,10,600,400);
   c47->Divide(1,2);
   const Int_t n = 20;
   Double_t x[n], y[n];
   for (Int_t i=0;i<n;i++) {
      x[i] = i*0.1;
      y[i] = 10*sin(x[i]+0.2)-6;
   }
   auto gr = new TGraph(n,x,y);
   gr->SetFillColor(38);
   gr->SetTitle(" ");
   c47->cd(1); gr->Draw("AB");
   c47->cd(2); gr->Draw("AB1");
}
End_Macro
 
\anchor GrP2
### Exclusion graphs
 
When a graph is painted with the option `C` or `L` it is
possible to draw a filled area on one side of the line. This is useful to show
exclusion zones.
 
This drawing mode is activated when the absolute value of the graph line
width (set by `SetLineWidth()`) is greater than 99. In that
case the line width number is interpreted as:
 
    100*ff+ll = ffll
 
- The two digits number `ll` represent the normal line width
- The two digits number  `ff` represent the filled area width.
- The sign of "ffll" allows to flip the filled area from one side of the line to the other.
 
The current fill area attributes are used to draw the hatched zone.
 
Begin_Macro(source)
../../../tutorials/graphs/exclusiongraph.C
End_Macro
 
\anchor GrP3
### Graphs with error bars
Three classes are available to handle graphs with error bars:
`TGraphErrors`, `TGraphAsymmErrors` and `TGraphBentErrors`.
The following drawing options are specific to graphs with error bars:
 
| Option   | Description                                                       |
|----------|-------------------------------------------------------------------|
| "Z"      | Do not draw small horizontal and vertical lines the end of the error bars. Without "Z", the default is to draw these. |
| ">"      | An arrow is drawn at the end of the error bars. The size of the arrow is set to 2/3 of the marker size. |
| \"\|>\" | A filled arrow is drawn at the end of the error bars. The size of the arrow is set to 2/3 of the marker size. |
| "X"      | Do not draw error bars.  By default, graph classes that have errors are drawn with the errors (TGraph itself has no errors, and so this option has no effect.) |
| \"\|\|\" | Draw only the small vertical/horizontal lines at the ends of the error bars, without drawing the bars themselves. This option is interesting to superimpose statistical-only errors on top of a graph with statistical+systematic errors. |
| "[]"     | Does the same as option \"\|\|\" except that it draws additional marks at the ends of the small vertical/horizontal lines. It makes plots less ambiguous in case several graphs are drawn on the same picture. |
| "0"      | By default, when a data point is outside the visible range along the Y axis, the error bars are not drawn. This option forces error bars' drawing for the data points outside the visible range along the Y axis (see example below). |
| "2"      | Error rectangles are drawn. |
| "3"      | A filled area is drawn through the end points of the vertical error bars. |
| "4"      | A smoothed filled area is drawn through the end points of the vertical error bars. |
| "5"      | Error rectangles are drawn like option "2". In addition the contour line around the boxes is drawn. This can be useful when boxes' fill colors are very light or in gray scale mode. |
 
 
`gStyle->SetErrorX(dx)` controls the size of the error along x.
`dx = 0` removes the error along x.
 
`gStyle->SetEndErrorSize(np)` controls the size of the lines
at the end of the error bars (when option 1 is used).
By default `np=1`. (np represents the number of pixels).
 
\anchor GrP3a
#### TGraphErrors
 
A `TGraphErrors` is a `TGraph` with error bars. The errors are
defined along X and Y and are symmetric: The left and right errors are the same
along X and the bottom and up errors are the same along Y.
 
Begin_Macro(source)
{
   auto c4 = new TCanvas("c4","c4",200,10,600,400);
   double x[] = {0, 1, 2, 3, 4};
   double y[] = {0, 2, 4, 1, 3};
   double ex[] = {0.1, 0.2, 0.3, 0.4, 0.5};
   double ey[] = {1, 0.5, 1, 0.5, 1};
   auto ge = new TGraphErrors(5, x, y, ex, ey);
   ge->SetTitle("A graph with errors");
   ge->Draw("ap");
}
End_Macro
 
The option "0" shows the error bars for data points outside range.
 
Begin_Macro(source)
{
   auto c48 = new TCanvas("c48","c48",200,10,600,400);
   float x[]     = {1,2,3};
   float err_x[] = {0,0,0};
   float err_y[] = {5,5,5};
   float y[]     = {1,4,9};
   auto tg = new TGraphErrors(3,x,y,err_x,err_y);
   c48->Divide(2,1);
   c48->cd(1); gPad->DrawFrame(0,0,4,8); tg->Draw("PC");
   c48->cd(2); gPad->DrawFrame(0,0,4,8); tg->Draw("0PC");
}
End_Macro
 
The option "3" shows the errors as a band.
 
Begin_Macro(source)
{
   auto c41 = new TCanvas("c41","c41",200,10,600,400);
   double x[] = {0, 1, 2, 3, 4};
   double y[] = {0, 2, 4, 1, 3};
   double ex[] = {0.1, 0.2, 0.3, 0.4, 0.5};
   double ey[] = {1, 0.5, 1, 0.5, 1};
   auto ge = new TGraphErrors(5, x, y, ex, ey);
   ge->SetTitle("Errors as a band");
   ge->SetFillColor(4);
   ge->SetFillStyle(3010);
   ge->Draw("a3");
}
End_Macro
 
The option "4" is similar to the option "3" except that the band
is smoothed. As the following picture shows, this option should be
used carefully because the smoothing algorithm may show some (huge)
"bouncing" effects. In some cases it looks nicer than option "3"
(because it is smooth) but it can be misleading.
 
Begin_Macro(source)
{
   auto c42 = new TCanvas("c42","c42",200,10,600,400);
   double x[] = {0, 1, 2, 3, 4};
   double y[] = {0, 2, 4, 1, 3};
   double ex[] = {0.1, 0.2, 0.3, 0.4, 0.5};
   double ey[] = {1, 0.5, 1, 0.5, 1};
   auto ge = new TGraphErrors(5, x, y, ex, ey);
   ge->SetTitle("Errors as a smooth band");
   ge->SetFillColor(6);
   ge->SetFillStyle(3005);
   ge->Draw("a4");
}
End_Macro
 
The following example shows how the option "[]" can be used to superimpose
systematic errors on top of a graph with statistical errors.
 
Begin_Macro(source)
{
   auto c43 = new TCanvas("c43","c43",200,10,600,400);
   c43->DrawFrame(0., -0.5, 6., 2);
 
   double x[5]    = {1, 2, 3, 4, 5};
   double zero[5] = {0, 0, 0, 0, 0};
 
   // data set (1) with stat and sys errors
   double py1[5]      = {1.2, 1.15, 1.19, 0.9, 1.4};
   double ey_stat1[5] = {0.2, 0.18, 0.17, 0.2, 0.4};
   double ey_sys1[5]  = {0.5, 0.71, 0.76, 0.5, 0.45};
 
   // data set (2) with stat and sys errors
   double y2[5]       = {0.25, 0.18, 0.29, 0.2, 0.21};
   double ey_stat2[5] = {0.2, 0.18, 0.17, 0.2, 0.4};
   double ey_sys2[5]  = {0.63, 0.19, 0.7, 0.2, 0.7};
 
   // Now draw data set (1)
 
   // We first have to draw it only with the stat errors
   auto graph1 = new TGraphErrors(5, x, py1, zero, ey_stat1);
   graph1->SetMarkerStyle(20);
   graph1->Draw("P");
 
   // Now we have to somehow depict the sys errors
 
   auto graph1_sys = new TGraphErrors(5, x, py1, zero, ey_sys1);
   graph1_sys->Draw("[]");
 
   // Now draw data set (2)
 
   // We first have to draw it only with the stat errors
   auto graph2 = new TGraphErrors(5, x, y2, zero, ey_stat2);
   graph2->SetMarkerStyle(24);
   graph2->Draw("P");
 
   // Now we have to somehow depict the sys errors
 
   auto graph2_sys = new TGraphErrors(5, x, y2, zero, ey_sys2);
   graph2_sys->Draw("[]");
}
End_Macro
 
\anchor GrP3b
#### TGraphAsymmErrors
A `TGraphAsymmErrors` is like a `TGraphErrors` but the errors
defined along X and Y are not symmetric: The left and right errors are
different along X and the bottom and up errors are different along Y.
 
Begin_Macro(source)
{
   auto c44 = new TCanvas("c44","c44",200,10,600,400);
   double ax[] = {0, 1, 2, 3, 4};
   double ay[] = {0, 2, 4, 1, 3};
   double aexl[] = {0.1, 0.2, 0.3, 0.4, 0.5};
   double aexh[] = {0.5, 0.4, 0.3, 0.2, 0.1};
   double aeyl[] = {1, 0.5, 1, 0.5, 1};
   double aeyh[] = {0.5, 1, 0.5, 1, 0.5};
   auto gae = new TGraphAsymmErrors(5, ax, ay, aexl, aexh, aeyl, aeyh);
   gae->SetTitle("Not symmetric errors");
   gae->SetFillColor(2);
   gae->SetFillStyle(3001);
   gae->Draw("a2");
   gae->Draw("p");
}
End_Macro
 
 
\anchor GrP3c
#### TGraphBentErrors
A `TGraphBentErrors` is like a `TGraphAsymmErrors`.
An extra parameter allows to bend the error bars to better see them
when several graphs are drawn on the same plot.
 
Begin_Macro(source)
{
   auto c45 = new TCanvas("c45","c45",200,10,600,400);
   const Int_t n = 10;
   Double_t x[n]  = {-0.22, 0.05, 0.25, 0.35, 0.5, 0.61,0.7,0.85,0.89,0.95};
   Double_t y[n]  = {1,2.9,5.6,7.4,9,9.6,8.7,6.3,4.5,1};
   Double_t exl[n] = {.05,.1,.07,.07,.04,.05,.06,.07,.08,.05};
   Double_t eyl[n] = {.8,.7,.6,.5,.4,.4,.5,.6,.7,.8};
   Double_t exh[n] = {.02,.08,.05,.05,.03,.03,.04,.05,.06,.03};
   Double_t eyh[n] = {.6,.5,.4,.3,.2,.2,.3,.4,.5,.6};
   Double_t exld[n] = {.0,.0,.0,.0,.0,.0,.0,.0,.0,.0};
   Double_t eyld[n] = {.0,.0,.05,.0,.0,.0,.0,.0,.0,.0};
   Double_t exhd[n] = {.0,.0,.0,.0,.0,.0,.0,.0,.0,.0};
   Double_t eyhd[n] = {.0,.0,.0,.0,.0,.0,.0,.0,.05,.0};
   auto gr = new TGraphBentErrors(n,x,y,exl,exh,eyl,eyh,exld,exhd,eyld,eyhd);
   gr->SetTitle("A graph with bend errors");
   gr->SetMarkerColor(4);
   gr->SetMarkerStyle(21);
   gr->Draw("ALP");
}
End_Macro
 
 
\anchor GrP3d
#### TGraphMultiErrors
A `TGraphMultiErrors` works basically the same way like a `TGraphAsymmErrors`.
It has the possibility to define more than one type / dimension of y-Errors.
This is useful if you want to plot statistic and systematic errors at once.
 
To be able to define different drawing options for the multiple error dimensions
the option string can consist of multiple blocks separated by semicolons.
The painting method assigns these blocks to the error dimensions. The first block
is always used for the general draw options and options concerning the x-Errors.
In case there are less than NErrorDimensions + 1 blocks in the option string
the first block is also used for the first error dimension which is reserved for
statistical errors. The remaining blocks are assigned to the remaining dimensions.
 
In addition to the draw options of options of `TGraphAsymmErrors` the following are possible:
 
| Option   | Block          | Description                                                       |
|----------|----------------|-------------------------------------------------------------------|
| "X0"     | First one only | Do not draw errors for points with x = 0 |
| "Y0"     | First one only | Do not draw errors for points with y = 0 |
| "s=%f"   | Any            | Scales the x-Errors with %f similar to `gStyle->SetErrorX(dx)` but does not affect them directly (Useful when used in addition with box errors to make the box only half as wide as the x-Errors e.g. s=0.5) |
| "S"      | First one only | Use individual TAttFill and TAttLine attributes for the different error dimensions instead of the global ones. |
 
 
Per default the Fill and Line Styles of the Graph are being used for all error
dimensions. To use the specific ones add the draw option "S" to the first block.
 
Begin_Macro(source)
{
   auto c47 = new TCanvas("c47","c47",200,10,600,400);
   double ax[]      = {0, 1, 2, 3, 4};
   double ay[]      = {0, 2, 4, 1, 3};
   double aexl[]    = {0.3, 0.3, 0.3, 0.3, 0.3};
   double aexh[]    = {0.3, 0.3, 0.3, 0.3, 0.3};
   double* aeylstat = new double[5]  {1, 0.5, 1, 0.5, 1};
   double* aeyhstat = new double[5]  {0.5, 1, 0.5, 1, 0.5};
   double* aeylsys  = new double[5]  {0.5, 0.4, 0.8, 0.3, 1.2};
   double* aeyhsys  = new double[5]  {0.6, 0.7, 0.6, 0.4, 0.8};
 
   TGraphMultiErrors* gme = new TGraphMultiErrors("gme", "TGraphMultiErrors Example", 5, ax, ay, aexl, aexh, aeylstat, aeyhstat);
   gme->AddYError(5, aeylsys, aeyhsys);
   gme->SetMarkerStyle(20);
   gme->SetLineColor(kRed);
   gme->GetAttLine(0)->SetLineColor(kRed);
   gme->GetAttLine(1)->SetLineColor(kBlue);
   gme->GetAttFill(1)->SetFillStyle(0);
 
   gme->Draw("a p s ; ; 5 s=0.5");
}
End_Macro
 
 
\anchor GrP4
### TGraphPolar options
 
The drawing options for the polar graphs are the following:
 
| Option   | Description                                                       |
|----------|-------------------------------------------------------------------|
| "O"      | Polar labels are drawn orthogonally to the polargram radius. |
| "P"      | Polymarker are drawn at each point position. |
| "E"      | Draw error bars. |
| "F"      | Draw fill area (closed polygon). |
| "A"      | Force axis redrawing even if a polargram already exists. |
| "N"      | Disable the display of the polar labels. |
 
 
Begin_Macro(source)
{
   auto c46 = new TCanvas("c46","c46",500,500);
   auto grP1 = new TGraphPolar();
   grP1->SetTitle("TGraphPolar example");
 
   grP1->SetPoint(0, (1*TMath::Pi())/4., 0.05);
   grP1->SetPoint(1, (2*TMath::Pi())/4., 0.10);
   grP1->SetPoint(2, (3*TMath::Pi())/4., 0.15);
   grP1->SetPoint(3, (4*TMath::Pi())/4., 0.20);
   grP1->SetPoint(4, (5*TMath::Pi())/4., 0.25);
   grP1->SetPoint(5, (6*TMath::Pi())/4., 0.30);
   grP1->SetPoint(6, (7*TMath::Pi())/4., 0.35);
   grP1->SetPoint(7, (8*TMath::Pi())/4., 0.40);
 
   grP1->SetMarkerStyle(20);
   grP1->SetMarkerSize(1.);
   grP1->SetMarkerColor(4);
   grP1->SetLineColor(4);
   grP1->Draw("ALP");
 
   // Update, otherwise GetPolargram returns 0
   c46->Update();
   grP1->GetPolargram()->SetToRadian();
}
End_Macro
 
\anchor GrP5
### Colors automatically picked in palette
 
\since **ROOT version 6.09/01**
 
When several graphs are painted in the same canvas or when a multi-graph is drawn,
it might be useful to have an easy and automatic way to choose
their color. The simplest way is to pick colors in the current active color
palette. Palette coloring for histogram is activated thanks to the options `PFC`
(Palette Fill Color), `PLC` (Palette Line Color) and `PMC` (Palette Marker Color).
When one of these options is given to `TGraph::Draw` the graph get its color
from the current color palette defined by `gStyle->SetPalette(...)`. The color
is determined according to the number of objects having palette coloring in
the current pad.
 
Begin_Macro(source)
../../../tutorials/graphs/graphpalettecolor.C
End_Macro
 
Begin_Macro(source)
../../../tutorials/graphs/multigraphpalettecolor.C
End_Macro
 
\anchor GrP6
### Reverse graphs' axis
 
\since **ROOT version 6.09/03**
 
When a TGraph is drawn, the X-axis is drawn with increasing values from left to
right and the Y-axis from bottom to top. The two options `RX` and `RY` allow to
change this order. The option `RX` allows to draw the X-axis with increasing values
from right to left and the `RY` option allows to draw the Y-axis with increasing
values from top to bottom. The following example illustrate how to use these options.
 
Begin_Macro(source)
{
   auto c = new TCanvas();
   c->Divide(2,1);
   auto g = new TGraphErrors();
   g->SetTitle("Simple Graph");
 
   g->SetPoint(0,-4,-3);
   g->SetPoint(1,1,1);
   g->SetPoint(2,2,1);
   g->SetPoint(3,3,4);
   g->SetPoint(4,5,5);
 
   g->SetPointError(0,1.,2.);
   g->SetPointError(1,2,1);
   g->SetPointError(2,2,3);
   g->SetPointError(3,3,2);
   g->SetPointError(4,4,5);
 
   g->GetXaxis()->SetNdivisions(520);
 
   g->SetMarkerStyle(21);
   c->cd(1); gPad->SetGrid(1,1);
   g->Draw("APL");
 
   c->cd(2); gPad->SetGrid(1,1);
   g->Draw("A RX RY PL");
}
End_Macro
 
\anchor GrP7
### Graphs in logarithmic scale
 
Like histograms, graphs can be drawn in logarithmic scale along X and Y. When
a pad is set to logarithmic scale with TPad::SetLogx() and/or with TPad::SetLogy()
the points building the graph are converted into logarithmic scale. But **only** the
points not the lines connecting them which stay linear. This can be clearly seen
on the following example:
 
Begin_Macro(source)
{
   // A graph with 3 points
   Double_t xmin = 750.;
   Double_t xmax = 1000;
   auto g = new TGraph(3);
   g->SetPoint(0,xmin,0.1);
   g->SetPoint(1,845,0.06504);
   g->SetPoint(2,xmax,0.008);
 
   // The same graph with n points
   Int_t n = 10000;
   Double_t dx = (xmax-xmin)/n;
   Double_t x = xmin;
   auto g2 = new TGraph();
   for (Int_t i=0; i<n; i++) {
      g2->SetPoint(i, x, g->Eval(x));
      x = x + dx;
   }
 
   auto cv = new TCanvas("cv","cv",800,600);
   cv->SetLogy();
   cv->SetGridx();
   cv->SetGridy();
   g->Draw("AL*");
 
   g2->SetMarkerColor(kRed);
   g2->SetMarkerStyle(1);
   g2->Draw("P");
}
 
End_Macro
 
\anchor GrP8
#### Highlight mode for graph
 
\since **ROOT version 6.15/01**
 
\image html hlGraph1.gif "Highlight mode"
 
Highlight mode is implemented for `TGraph` (and for `TH1`) class. When
highlight mode is on, mouse movement over the point will be represented
graphically. Point will be highlighted as "point circle" (presented by
marker object). Moreover, any highlight (change of point) emits signal
`TCanvas::Highlighted()` which allows the user to react and call their own
function. For a better understanding please see also the tutorials
`$ROOTSYS/tutorials/graphs/hlGraph*.C` files.
 
Highlight mode is switched on/off by `TGraph::SetHighlight()` function
or interactively from `TGraph` context menu. `TGraph::IsHighlight()` to verify
whether the highlight mode enabled or disabled, default it is disabled.
 
~~~ {.cpp}
    root [0] .x $ROOTSYS/tutorials/graphs/gerrors2.C
    root [1] // try SetHighlight() interactively from TGraph context menu
~~~
 
\image html hlgerrors2.gif "Highlight mode for graph"
 
See how it is used
<a href="classTHistPainter.html#HP30a">highlight mode and user function</a>
(is fully equivalent as for histogram).
 
NOTE all parameters of user function are taken from
 
    void TCanvas::Highlighted(TVirtualPad *pad, TObject *obj, Int_t x, Int_t y)
 
  - `pad` is pointer to pad with highlighted graph
  - `obj` is pointer to highlighted graph
  - `x` is highlighted x-th (i-th) point for graph
  - `y` not in use (only for 2D histogram)
 
For more complex demo please see for example `$ROOTSYS/tutorials/math/hlquantiles.C` file.
 
*/
 
 
////////////////////////////////////////////////////////////////////////////////
/// Default constructor
 
TGraphPainter::TGraphPainter()
{
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Destructor.
 
TGraphPainter::~TGraphPainter()
{
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Compute the logarithm of variables `gxwork` and `gywork`
///  according to the value of Options and put the results
///  in the  variables `gxworkl` and `gyworkl`.
///
/// npoints : Number of points in gxwork and in gywork.
///
/// - opt = 1 ComputeLogs is called from PaintGrapHist
/// - opt = 0 ComputeLogs is called from PaintGraph
 
void TGraphPainter::ComputeLogs(Int_t npoints, Int_t opt)
{
   if (gPad->GetLogx()) {
      for (Int_t i = 0; i < npoints; i++) {
         gxworkl[i] = (gxwork[i] > 0.) ? TMath::Log10(gxwork[i]) : gPad->GetX1();
      }
   } else {
      for (Int_t i = 0; i < npoints; i++)
         gxworkl[i] = gxwork[i];
   }
   if (!opt && gPad->GetLogy()) {
      for (Int_t i = 0; i < npoints; i++) {
         gyworkl[i] = (gywork[i] > 0.) ? TMath::Log10(gywork[i]) : gPad->GetY1();
      }
   } else {
      for (Int_t i = 0; i < npoints; i++)
         gyworkl[i] = gywork[i];
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Compute distance from point px,py to a graph.
///
/// Compute the closest distance of approach from point px,py to this line.
/// The distance is computed in pixels units.
 
Int_t TGraphPainter::DistancetoPrimitiveHelper(TGraph *theGraph, Int_t px, Int_t py)
{
 
   // Are we on the axis?
   Int_t distance;
   if (theGraph->GetHistogram()) {
      distance = theGraph->GetHistogram()->DistancetoPrimitive(px,py);
      if (distance <= 5) return distance;
   }
 
   // Somewhere on the graph points?
   const Int_t big = 9999;
   const Int_t kMaxDiff = 10;
 
   // check if point is near one of the graph points
   Int_t i, pxp, pyp, d;
   distance = big;
 
   Int_t theNpoints = theGraph->GetN();
   Double_t *theX, *theY;
   if (theGraph->InheritsFrom(TGraphPolar::Class())) {
      TGraphPolar *theGraphPolar = (TGraphPolar*) theGraph;
      theX   = theGraphPolar->GetXpol();
      theY   = theGraphPolar->GetYpol();
   } else {
      theX   = theGraph->GetX();
      theY   = theGraph->GetY();
   }
 
   Int_t hpoint = -1;
   for (i=0;i<theNpoints;i++) {
      pxp = gPad->XtoAbsPixel(gPad->XtoPad(theX[i]));
      pyp = gPad->YtoAbsPixel(gPad->YtoPad(theY[i]));
      d   = TMath::Abs(pxp-px) + TMath::Abs(pyp-py);
      if (d < distance) {
         distance = d;
         hpoint = i;
      }
   }
 
   if (theGraph->IsHighlight()) // only if highlight is enable
      HighlightPoint(theGraph, hpoint, distance);
   if (distance < kMaxDiff) return distance;
 
   for (i=0;i<theNpoints-1;i++) {
      TAttLine l;
      d = l.DistancetoLine(px, py, gPad->XtoPad(theX[i]), gPad->YtoPad(theY[i]), gPad->XtoPad(theX[i+1]), gPad->YtoPad(theY[i+1]));
      if (d < distance) distance = d;
   }
 
   // If graph has been drawn with the fill area option, check if we are inside
   TString drawOption = theGraph->GetDrawOption();
   drawOption.ToLower();
   if (drawOption.Contains("f")) {
      Double_t xp = gPad->AbsPixeltoX(px); xp = gPad->PadtoX(xp);
      Double_t yp = gPad->AbsPixeltoY(py); yp = gPad->PadtoY(yp);
      if (TMath::IsInside(xp,yp,theNpoints,theX,theY) != 0) distance = 1;
   }
 
   // Loop on the list of associated functions and user objects
   TObject *f;
   TList *functions = theGraph->GetListOfFunctions();
   TIter   next(functions);
   while ((f = (TObject*) next())) {
      if (f->InheritsFrom(TF1::Class())) distance = f->DistancetoPrimitive(-px,py);
      else                               distance = f->DistancetoPrimitive(px,py);
      if (distance < kMaxDiff) {
         gPad->SetSelected(f);
         return 0; //must be o and not dist in case of TMultiGraph
      }
   }
 
   return distance;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Display a panel with all histogram drawing options.
 
void TGraphPainter::DrawPanelHelper(TGraph *theGraph)
{
 
   if (!gPad) {
      Error("DrawPanel", "need to draw graph first");
      return;
   }
   TVirtualPadEditor *editor = TVirtualPadEditor::GetPadEditor();
   editor->Show();
   gROOT->ProcessLine(TString::Format("((TCanvas*)0x%zx)->Selected((TVirtualPad*)0x%zx,(TObject*)0x%zx,1)",
                                      (size_t)gPad->GetCanvas(), (size_t)gPad, (size_t)theGraph));
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Execute action corresponding to one event.
///
/// This member function is called when a graph is clicked with the locator.
///
/// If the left mouse button is clicked on one of the line end points, this point
/// follows the cursor until button is released.
///
/// If the middle mouse button clicked, the line is moved parallel to itself
/// until the button is released.
 
void TGraphPainter::ExecuteEventHelper(TGraph *theGraph, Int_t event, Int_t px, Int_t py)
{
 
   if (!gPad) return;
 
   Int_t i, d;
   Double_t xmin, xmax, ymin, ymax, dx, dy, dxr, dyr;
   const Int_t kMaxDiff =  10;//3;
   static Bool_t middle, badcase;
   static Int_t ipoint, pxp, pyp;
   static Int_t px1,px2,py1,py2;
   static Int_t pxold, pyold, px1old, py1old, px2old, py2old;
   static Int_t dpx, dpy;
   static std::vector<Int_t> x, y;
   Bool_t opaque  = gPad->OpaqueMoving();
 
   if (!theGraph->IsEditable() || theGraph->InheritsFrom(TGraphPolar::Class())) {
      gPad->SetCursor(kHand);
      return;
   }
   if (!gPad->IsEditable()) return;
   Int_t theNpoints = theGraph->GetN();
   Double_t *theX  = theGraph->GetX();
   Double_t *theY  = theGraph->GetY();
 
   switch (event) {
 
   case kButton1Down:
      badcase = kFALSE;
      gVirtualX->SetLineColor(-1);
      theGraph->TAttLine::Modify();  //Change line attributes only if necessary
      px1 = gPad->XtoAbsPixel(gPad->GetX1());
      py1 = gPad->YtoAbsPixel(gPad->GetY1());
      px2 = gPad->XtoAbsPixel(gPad->GetX2());
      py2 = gPad->YtoAbsPixel(gPad->GetY2());
      ipoint = -1;
 
 
      if (!x.empty() || !y.empty()) break;
      x.resize(theNpoints+1);
      y.resize(theNpoints+1);
      for (i=0;i<theNpoints;i++) {
         pxp = gPad->XtoAbsPixel(gPad->XtoPad(theX[i]));
         pyp = gPad->YtoAbsPixel(gPad->YtoPad(theY[i]));
         if (pxp < -kMaxPixel || pxp >= kMaxPixel ||
             pyp < -kMaxPixel || pyp >= kMaxPixel) {
            badcase = kTRUE;
            continue;
         }
         if (!opaque) {
            gVirtualX->DrawLine(pxp-4, pyp-4, pxp+4,  pyp-4);
            gVirtualX->DrawLine(pxp+4, pyp-4, pxp+4,  pyp+4);
            gVirtualX->DrawLine(pxp+4, pyp+4, pxp-4,  pyp+4);
            gVirtualX->DrawLine(pxp-4, pyp+4, pxp-4,  pyp-4);
         }
         x[i] = pxp;
         y[i] = pyp;
         d   = TMath::Abs(pxp-px) + TMath::Abs(pyp-py);
         if (d < kMaxDiff) ipoint =i;
      }
      dpx = 0;
      dpy = 0;
      pxold = px;
      pyold = py;
      if (ipoint < 0) return;
      if (ipoint == 0) {
         px1old = 0;
         py1old = 0;
         px2old = gPad->XtoAbsPixel(theX[1]);
         py2old = gPad->YtoAbsPixel(theY[1]);
      } else if (ipoint == theNpoints-1) {
         px1old = gPad->XtoAbsPixel(gPad->XtoPad(theX[theNpoints-2]));
         py1old = gPad->YtoAbsPixel(gPad->YtoPad(theY[theNpoints-2]));
         px2old = 0;
         py2old = 0;
      } else {
         px1old = gPad->XtoAbsPixel(gPad->XtoPad(theX[ipoint-1]));
         py1old = gPad->YtoAbsPixel(gPad->YtoPad(theY[ipoint-1]));
         px2old = gPad->XtoAbsPixel(gPad->XtoPad(theX[ipoint+1]));
         py2old = gPad->YtoAbsPixel(gPad->YtoPad(theY[ipoint+1]));
      }
      pxold = gPad->XtoAbsPixel(gPad->XtoPad(theX[ipoint]));
      pyold = gPad->YtoAbsPixel(gPad->YtoPad(theY[ipoint]));
 
      break;
 
 
   case kMouseMotion:
 
      middle = kTRUE;
      for (i=0;i<theNpoints;i++) {
         pxp = gPad->XtoAbsPixel(gPad->XtoPad(theX[i]));
         pyp = gPad->YtoAbsPixel(gPad->YtoPad(theY[i]));
         d   = TMath::Abs(pxp-px) + TMath::Abs(pyp-py);
         if (d < kMaxDiff) middle = kFALSE;
      }
 
 
   // check if point is close to an axis
      if (middle) gPad->SetCursor(kMove);
      else gPad->SetCursor(kHand);
      break;
 
   case kButton1Motion:
      if (!opaque) {
         if (middle) {
            for(i=0;i<theNpoints-1;i++) {
               gVirtualX->DrawLine(x[i]+dpx, y[i]+dpy, x[i+1]+dpx, y[i+1]+dpy);
               pxp = x[i]+dpx;
               pyp = y[i]+dpy;
               if (pxp < -kMaxPixel || pxp >= kMaxPixel ||
                   pyp < -kMaxPixel || pyp >= kMaxPixel) continue;
               gVirtualX->DrawLine(pxp-4, pyp-4, pxp+4,  pyp-4);
               gVirtualX->DrawLine(pxp+4, pyp-4, pxp+4,  pyp+4);
               gVirtualX->DrawLine(pxp+4, pyp+4, pxp-4,  pyp+4);
               gVirtualX->DrawLine(pxp-4, pyp+4, pxp-4,  pyp-4);
            }
            pxp = x[theNpoints-1]+dpx;
            pyp = y[theNpoints-1]+dpy;
            gVirtualX->DrawLine(pxp-4, pyp-4, pxp+4,  pyp-4);
            gVirtualX->DrawLine(pxp+4, pyp-4, pxp+4,  pyp+4);
            gVirtualX->DrawLine(pxp+4, pyp+4, pxp-4,  pyp+4);
            gVirtualX->DrawLine(pxp-4, pyp+4, pxp-4,  pyp-4);
            dpx += px - pxold;
            dpy += py - pyold;
            pxold = px;
            pyold = py;
            for(i=0;i<theNpoints-1;i++) {
               gVirtualX->DrawLine(x[i]+dpx, y[i]+dpy, x[i+1]+dpx, y[i+1]+dpy);
               pxp = x[i]+dpx;
               pyp = y[i]+dpy;
               if (pxp < -kMaxPixel || pxp >= kMaxPixel ||
                   pyp < -kMaxPixel || pyp >= kMaxPixel) continue;
               gVirtualX->DrawLine(pxp-4, pyp-4, pxp+4,  pyp-4);
               gVirtualX->DrawLine(pxp+4, pyp-4, pxp+4,  pyp+4);
               gVirtualX->DrawLine(pxp+4, pyp+4, pxp-4,  pyp+4);
               gVirtualX->DrawLine(pxp-4, pyp+4, pxp-4,  pyp-4);
            }
            pxp = x[theNpoints-1]+dpx;
            pyp = y[theNpoints-1]+dpy;
            gVirtualX->DrawLine(pxp-4, pyp-4, pxp+4,  pyp-4);
            gVirtualX->DrawLine(pxp+4, pyp-4, pxp+4,  pyp+4);
            gVirtualX->DrawLine(pxp+4, pyp+4, pxp-4,  pyp+4);
            gVirtualX->DrawLine(pxp-4, pyp+4, pxp-4,  pyp-4);
         } else {
            if (px1old) gVirtualX->DrawLine(px1old, py1old, pxold,  pyold);
            if (px2old) gVirtualX->DrawLine(pxold,  pyold,  px2old, py2old);
            gVirtualX->DrawLine(pxold-4, pyold-4, pxold+4,  pyold-4);
            gVirtualX->DrawLine(pxold+4, pyold-4, pxold+4,  pyold+4);
            gVirtualX->DrawLine(pxold+4, pyold+4, pxold-4,  pyold+4);
            gVirtualX->DrawLine(pxold-4, pyold+4, pxold-4,  pyold-4);
            pxold = px;
            pxold = TMath::Max(pxold, px1);
            pxold = TMath::Min(pxold, px2);
            pyold = py;
            pyold = TMath::Max(pyold, py2);
            pyold = TMath::Min(pyold, py1);
            if (px1old) gVirtualX->DrawLine(px1old, py1old, pxold,  pyold);
            if (px2old) gVirtualX->DrawLine(pxold,  pyold,  px2old, py2old);
            gVirtualX->DrawLine(pxold-4, pyold-4, pxold+4,  pyold-4);
            gVirtualX->DrawLine(pxold+4, pyold-4, pxold+4,  pyold+4);
            gVirtualX->DrawLine(pxold+4, pyold+4, pxold-4,  pyold+4);
            gVirtualX->DrawLine(pxold-4, pyold+4, pxold-4,  pyold-4);
         }
      } else {
         xmin = gPad->GetUxmin();
         xmax = gPad->GetUxmax();
         ymin = gPad->GetUymin();
         ymax = gPad->GetUymax();
         dx   = xmax-xmin;
         dy   = ymax-ymin;
         dxr  = dx/(1 - gPad->GetLeftMargin() - gPad->GetRightMargin());
         dyr  = dy/(1 - gPad->GetBottomMargin() - gPad->GetTopMargin());
 
         if (theGraph->GetHistogram()) {
            // Range() could change the size of the pad pixmap and therefore should
            // be called before the other paint routines
            gPad->Range(xmin - dxr*gPad->GetLeftMargin(),
                         ymin - dyr*gPad->GetBottomMargin(),
                         xmax + dxr*gPad->GetRightMargin(),
                         ymax + dyr*gPad->GetTopMargin());
            gPad->RangeAxis(xmin, ymin, xmax, ymax);
         }
         if (middle) {
            dpx += px - pxold;
            dpy += py - pyold;
            pxold = px;
            pyold = py;
            for(i=0;i<theNpoints;i++) {
               if (badcase) continue;  //do not update if big zoom and points moved
               if (!x.empty()) theX[i] = gPad->PadtoX(gPad->AbsPixeltoX(x[i]+dpx));
               if (!y.empty()) theY[i] = gPad->PadtoY(gPad->AbsPixeltoY(y[i]+dpy));
            }
         } else {
            pxold = px;
            pxold = TMath::Max(pxold, px1);
            pxold = TMath::Min(pxold, px2);
            pyold = py;
            pyold = TMath::Max(pyold, py2);
            pyold = TMath::Min(pyold, py1);
            theX[ipoint] = gPad->PadtoX(gPad->AbsPixeltoX(pxold));
            theY[ipoint] = gPad->PadtoY(gPad->AbsPixeltoY(pyold));
            if (theGraph->InheritsFrom("TCutG")) {
               //make sure first and last point are the same
               if (ipoint == 0) {
                  theX[theNpoints-1] = theX[0];
                  theY[theNpoints-1] = theY[0];
               }
               if (ipoint == theNpoints-1) {
                  theX[0] = theX[theNpoints-1];
                  theY[0] = theY[theNpoints-1];
               }
            }
         }
         badcase = kFALSE;
         gPad->Modified(kTRUE);
         //gPad->Update();
      }
      break;
 
   case kButton1Up:
 
      if (gROOT->IsEscaped()) {
         gROOT->SetEscape(kFALSE);
         x.clear();
         y.clear();
         break;
      }
 
   // Compute x,y range
      xmin = gPad->GetUxmin();
      xmax = gPad->GetUxmax();
      ymin = gPad->GetUymin();
      ymax = gPad->GetUymax();
      dx   = xmax-xmin;
      dy   = ymax-ymin;
      dxr  = dx/(1 - gPad->GetLeftMargin() - gPad->GetRightMargin());
      dyr  = dy/(1 - gPad->GetBottomMargin() - gPad->GetTopMargin());
 
      if (theGraph->GetHistogram()) {
         // Range() could change the size of the pad pixmap and therefore should
         // be called before the other paint routines
         gPad->Range(xmin - dxr*gPad->GetLeftMargin(),
                      ymin - dyr*gPad->GetBottomMargin(),
                      xmax + dxr*gPad->GetRightMargin(),
                      ymax + dyr*gPad->GetTopMargin());
         gPad->RangeAxis(xmin, ymin, xmax, ymax);
      }
      if (middle) {
         for(i=0;i<theNpoints;i++) {
            if (badcase) continue;  //do not update if big zoom and points moved
            if (!x.empty()) theX[i] = gPad->PadtoX(gPad->AbsPixeltoX(x[i]+dpx));
            if (!y.empty()) theY[i] = gPad->PadtoY(gPad->AbsPixeltoY(y[i]+dpy));
         }
      } else {
         theX[ipoint] = gPad->PadtoX(gPad->AbsPixeltoX(pxold));
         theY[ipoint] = gPad->PadtoY(gPad->AbsPixeltoY(pyold));
         if (theGraph->InheritsFrom("TCutG")) {
            //make sure first and last point are the same
            if (ipoint == 0) {
               theX[theNpoints-1] = theX[0];
               theY[theNpoints-1] = theY[0];
            }
            if (ipoint == theNpoints-1) {
               theX[0] = theX[theNpoints-1];
               theY[0] = theY[theNpoints-1];
            }
         }
      }
      badcase = kFALSE;
      x.clear();
      y.clear();
      gPad->Modified(kTRUE);
      gVirtualX->SetLineColor(-1);
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
 
char *TGraphPainter::GetObjectInfoHelper(TGraph * /*theGraph*/, Int_t /*px*/, Int_t /*py*/) const
{
   return (char*)"";
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Return the highlighted point for theGraph
 
Int_t TGraphPainter::GetHighlightPoint(TGraph *theGraph) const
{
   if (theGraph == gHighlightGraph) return gHighlightPoint;
   else return -1;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Set highlight (enable/disable) mode for theGraph
 
void TGraphPainter::SetHighlight(TGraph *theGraph)
{
   gHighlightPoint = -1; // must be -1
   gHighlightGraph = nullptr;
   if (theGraph->IsHighlight()) return;
 
   // delete previous highlight marker
   if (gHighlightMarker) gHighlightMarker.reset(nullptr);
   // emit Highlighted() signal (user can check on disabled)
   if (gPad->GetCanvas()) gPad->GetCanvas()->Highlighted(gPad, theGraph, gHighlightPoint, -1);
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Check on highlight point
 
void TGraphPainter::HighlightPoint(TGraph *theGraph, Int_t hpoint, Int_t distance)
{
   // call from DistancetoPrimitiveHelper (only if highlight is enable)
 
   const Int_t kHighlightRange = 50; // maybe as fgHighlightRange and Set/Get
   static Int_t distanceOld = kHighlightRange;
   if (gHighlightPoint == -1) distanceOld = kHighlightRange; // reset
 
   if ((distance < kHighlightRange) && (distance < distanceOld)) { // closest point
      if ((gHighlightPoint != hpoint) || (gHighlightGraph != theGraph)) { // was changed
         //   Info("HighlightPoint", "graph: %p\tpoint: %d", (void *)theGraph, hpoint);
         gHighlightPoint = hpoint;
         gHighlightGraph = theGraph;
 
         // paint highlight point as marker (recursive calls PaintHighlightPoint)
         gPad->Modified(kTRUE);
         gPad->Update();
 
         // emit Highlighted() signal
         if (gPad->GetCanvas()) gPad->GetCanvas()->Highlighted(gPad, theGraph, gHighlightPoint, -1);
      }
   }
   if (gHighlightGraph == theGraph) distanceOld = distance;
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint highlight point as TMarker object (open circle)
 
void TGraphPainter::PaintHighlightPoint(TGraph *theGraph, Option_t * /*option*/)
{
   // call from PaintGraphSimple
 
   if ((!theGraph->IsHighlight()) || (gHighlightGraph != theGraph)) return;
 
   Double_t hx, hy;
   if (theGraph->GetPoint(gHighlightPoint, hx, hy) == -1) {
      // special case, e.g. after interactive remove last point
      if (gHighlightMarker) gHighlightMarker.reset(nullptr);
      return;
   }
   // testing specific possibility (after zoom, draw with "same", log, etc.)
   Double_t uxmin = gPad->GetUxmin();
   Double_t uxmax = gPad->GetUxmax();
   Double_t uymin = gPad->GetUymin();
   Double_t uymax = gPad->GetUymax();
   if (gPad->GetLogx()) {
      uxmin = TMath::Power(10.0, uxmin);
      uxmax = TMath::Power(10.0, uxmax);
   }
   if (gPad->GetLogy()) {
      uymin = TMath::Power(10.0, uymin);
      uymax = TMath::Power(10.0, uymax);
   }
   if ((hx < uxmin) || (hx > uxmax)) return;
   if ((hy < uymin) || (hy > uymax)) return;
 
   if (!gHighlightMarker) {
      gHighlightMarker = std::make_unique<TMarker>(hx, hy, 24);
      gHighlightMarker->SetBit(kCannotPick);
   }
   gHighlightMarker->SetX(hx);
   gHighlightMarker->SetY(hy);
   gHighlightMarker->SetMarkerSize(theGraph->GetMarkerSize()*2.0);
   if (gHighlightMarker->GetMarkerSize() < 1.0) gHighlightMarker->SetMarkerSize(1.0); // always visible
   gHighlightMarker->SetMarkerColor(theGraph->GetMarkerColor());
   gHighlightMarker->Paint();
   //   Info("PaintHighlightPoint", "graph: %p\tpoint: %d",
   //        (void *)gHighlightGraph, gHighlightPoint);
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint a any kind of TGraph
 
void TGraphPainter::PaintHelper(TGraph *theGraph, Option_t *option)
{
 
   char chopt[80];
   strlcpy(chopt,option,80);
 
   if (theGraph) {
      char *l1 = strstr(chopt,"pfc"); // Automatic Fill Color
      char *l2 = strstr(chopt,"plc"); // Automatic Line Color
      char *l3 = strstr(chopt,"pmc"); // Automatic Marker Color
      if (l1 || l2 || l3) {
         Int_t i = gPad->NextPaletteColor();
         if (l1) {memcpy(l1,"   ",3); theGraph->SetFillColor(i);}
         if (l2) {memcpy(l2,"   ",3); theGraph->SetLineColor(i);}
         if (l3) {memcpy(l3,"   ",3); theGraph->SetMarkerColor(i);}
      }
 
      SetBit(TGraph::kClipFrame, theGraph->TestBit(TGraph::kClipFrame));
 
      char *l4 = strstr(chopt,"rx"); // Reverse graph along X axis
      char *l5 = strstr(chopt,"ry"); // Reverse graph along Y axis
 
      if (l4 || l5) {
         PaintGraphReverse(theGraph,chopt);
         return;
      }
 
      if (theGraph->InheritsFrom(TGraphBentErrors::Class())) {
         PaintGraphBentErrors(theGraph,chopt);
      } else if (theGraph->InheritsFrom(TGraphQQ::Class())) {
         PaintGraphQQ(theGraph,chopt);
      } else if (theGraph->InheritsFrom(TGraphAsymmErrors::Class())) {
         PaintGraphAsymmErrors(theGraph,chopt);
      } else if (theGraph->InheritsFrom(TGraphMultiErrors::Class())) {
        PaintGraphMultiErrors(theGraph,chopt);
      } else if (theGraph->InheritsFrom(TGraphErrors::Class())) {
         if (theGraph->InheritsFrom(TGraphPolar::Class())) {
            PaintGraphPolar(theGraph,chopt);
         } else {
            PaintGraphErrors(theGraph,chopt);
         }
      } else {
         PaintGraphSimple(theGraph,chopt);
      }
 
      // Paint the fit parameters if needed.
      TF1 *fit = nullptr;
      TList *functions = theGraph->GetListOfFunctions();
      TObject *f;
      if (functions) {
         f = (TF1*)functions->First();
         if (f) {
            if (f->InheritsFrom(TF1::Class())) fit = (TF1*)f;
         }
         TIter   next(functions);
         while ((f = (TObject*) next())) {
            if (f->InheritsFrom(TF1::Class())) {
               fit = (TF1*)f;
               break;
            }
         }
         TPaletteAxis *palette = (TPaletteAxis*)functions->FindObject("palette");
         if (palette) palette->Paint();
      }
      if (fit && !theGraph->TestBit(TGraph::kNoStats)) PaintStats(theGraph, fit);
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// [Control function to draw a graph.](\ref GrP1)
 
void TGraphPainter::PaintGraph(TGraph *theGraph, Int_t npoints, const Double_t *x, const Double_t *y, Option_t *chopt)
{
 
   if (theGraph->InheritsFrom("TGraphPolar"))
      gPad->PushSelectableObject(theGraph);
 
   Int_t optionLine , optionAxis , optionCurve    , optionStar , optionMark;
   Int_t optionBar  , optionR    , optionOne      , optionE;
   Int_t optionFill , optionZ    , optionCurveFill, optionIAxis;
   Int_t i, npt, nloop;
   Int_t drawtype=0;
   Double_t xlow, xhigh, ylow, yhigh;
   Double_t barxmin, barxmax, barymin, barymax;
   Double_t uxmin, uxmax;
   Double_t x1, xn, y1, yn;
   Double_t dbar, bdelta;
   Int_t theNpoints = theGraph->GetN();
 
   if (npoints <= 0) {
      Error("PaintGraph", "illegal number of points (%d)", npoints);
      return;
   }
   TString opt = chopt;
   opt.ToUpper();
   opt.ReplaceAll("SAME","");
 
   if (opt.Contains("L")) optionLine  = 1;  else optionLine  = 0;
   if (opt.Contains("A")) optionAxis  = 1;  else optionAxis  = 0;
   if (opt.Contains("C")) optionCurve = 1;  else optionCurve = 0;
   if (opt.Contains("*")) optionStar  = 1;  else optionStar  = 0;
   if (opt.Contains("P")) optionMark  = 1;  else optionMark  = 0;
   if (opt.Contains("B")) optionBar   = 1;  else optionBar   = 0;
   if (opt.Contains("R")) optionR     = 1;  else optionR     = 0;
   if (opt.Contains("1")) optionOne   = 1;  else optionOne   = 0;
   if (opt.Contains("F")) optionFill  = 1;  else optionFill  = 0;
   if (opt.Contains("I")) optionIAxis = 1;  else optionIAxis = 0;
   if (opt.Contains("2") || opt.Contains("3") ||
      opt.Contains("4") || opt.Contains("5")) optionE = 1;  else optionE = 0;
   optionZ    = 0;
 
   // If no "drawing" option is selected and if chopt<>' ' nothing is done.
   if (optionLine+optionFill+optionCurve+optionStar+optionMark+optionBar+optionE == 0) {
      if (!chopt[0])  optionLine=1;
      else   return;
   }
 
   if (optionStar) theGraph->SetMarkerStyle(3);
 
   optionCurveFill = 0;
   if (optionCurve && optionFill) {
      optionCurveFill = 1;
      optionFill      = 0;
   }
 
   // Draw the Axis.
   Double_t rwxmin,rwxmax, rwymin, rwymax, maximum, minimum, dx, dy;
   if (optionAxis) {
      if (theGraph->GetHistogram()) {
         rwxmin    = gPad->GetUxmin();
         rwxmax    = gPad->GetUxmax();
         rwymin    = gPad->GetUymin();
         rwymax    = gPad->GetUymax();
         minimum   = theGraph->GetHistogram()->GetMinimumStored();
         maximum   = theGraph->GetHistogram()->GetMaximumStored();
         if (minimum == -1111) { //this can happen after unzooming
            minimum = theGraph->GetHistogram()->GetYaxis()->GetXmin();
            theGraph->GetHistogram()->SetMinimum(minimum);
         }
         if (maximum == -1111) {
            maximum = theGraph->GetHistogram()->GetYaxis()->GetXmax();
            theGraph->GetHistogram()->SetMaximum(maximum);
         }
         uxmin     = gPad->PadtoX(rwxmin);
         uxmax     = gPad->PadtoX(rwxmax);
      } else {
 
         theGraph->ComputeRange(rwxmin, rwymin, rwxmax, rwymax);  //this is redefined in TGraphErrors
 
         if (rwxmin == rwxmax) rwxmax += 1.;
         if (rwymin == rwymax) rwymax += 1.;
         dx = 0.1*(rwxmax-rwxmin);
         dy = 0.1*(rwymax-rwymin);
         uxmin    = rwxmin - dx;
         uxmax    = rwxmax + dx;
         minimum  = rwymin - dy;
         maximum  = rwymax + dy;
      }
      if (theGraph->GetMinimum() != -1111) rwymin = minimum = theGraph->GetMinimum();
      if (theGraph->GetMaximum() != -1111) rwymax = maximum = theGraph->GetMaximum();
      if (uxmin < 0 && rwxmin >= 0) uxmin = 0.9*rwxmin;
      if (uxmax > 0 && rwxmax <= 0) {
         if (gPad->GetLogx()) uxmax = 1.1*rwxmax;
         else                 uxmax = 0;
      }
      if (minimum < 0 && rwymin >= 0) minimum = 0.9*rwymin;
      if (maximum > 0 && rwymax <= 0) {
         //if(gPad->GetLogy()) maximum = 1.1*rwymax;
         //else                maximum = 0;
      }
      if (minimum <= 0 && gPad->GetLogy()) minimum = 0.001*maximum;
      if (uxmin <= 0 && gPad->GetLogx()) {
         if (uxmax > 1000) uxmin = 1;
         else              uxmin = 0.001*uxmax;
      }
      rwymin = minimum;
      rwymax = maximum;
 
      // Create a temporary histogram and fill each bin with the
      // function value.
      char chopth[8] = " ";
      if (strstr(chopt,"x+")) strncat(chopth, "x+",3);
      if (strstr(chopt,"y+")) strncat(chopth, "y+",3);
      if (optionIAxis) strncat(chopth, "A",2);
      if (!theGraph->GetHistogram()) {
         // the graph is created with at least as many bins as there are
         // points to permit zooming on the full range.
         rwxmin = uxmin;
         rwxmax = uxmax;
         npt = 100;
         if (theNpoints > npt) npt = theNpoints;
         TH1F *h = new TH1F(TString::Format("%s_h",GetName()),GetTitle(),npt,rwxmin,rwxmax);
         theGraph->SetHistogram(h);
         if (!theGraph->GetHistogram()) return;
         theGraph->GetHistogram()->SetMinimum(rwymin);
         theGraph->GetHistogram()->SetMaximum(rwymax);
         theGraph->GetHistogram()->GetYaxis()->SetLimits(rwymin,rwymax);
         theGraph->GetHistogram()->SetBit(TH1::kNoStats);
         theGraph->GetHistogram()->SetDirectory(nullptr);
         theGraph->GetHistogram()->Sumw2(kFALSE);
         theGraph->GetHistogram()->Paint(chopth); // Draw histogram axis, title and grid
      } else {
         if (gPad->GetLogy()) {
            theGraph->GetHistogram()->SetMinimum(rwymin);
            theGraph->GetHistogram()->SetMaximum(rwymax);
            theGraph->GetHistogram()->GetYaxis()->SetLimits(rwymin,rwymax);
         }
         theGraph->GetHistogram()->Sumw2(kFALSE);
         theGraph->GetHistogram()->Paint(chopth); // Draw histogram axis, title and grid
      }
   }
 
   // Set Clipping option
   gPad->SetBit(TGraph::kClipFrame, theGraph->TestBit(TGraph::kClipFrame));
 
   rwxmin   = gPad->GetUxmin();
   rwxmax   = gPad->GetUxmax();
   rwymin   = gPad->GetUymin();
   rwymax   = gPad->GetUymax();
   uxmin    = gPad->PadtoX(rwxmin);
   uxmax    = gPad->PadtoX(rwxmax);
   if (theGraph->GetHistogram() && !theGraph->InheritsFrom("TGraphPolar")) {
      maximum = theGraph->GetHistogram()->GetMaximum();
      minimum = theGraph->GetHistogram()->GetMinimum();
   } else {
      maximum = gPad->PadtoY(rwymax);
      minimum = gPad->PadtoY(rwymin);
   }
 
   // Set attributes
   theGraph->TAttLine::Modify();
   theGraph->TAttFill::Modify();
   theGraph->TAttMarker::Modify();
 
   // Draw the graph with a polyline or a fill area
   gxwork.resize(2*npoints+10);
   gywork.resize(2*npoints+10);
   gxworkl.resize(2*npoints+10);
   gyworkl.resize(2*npoints+10);
 
   if (optionLine || optionFill) {
      x1    = x[0];
      xn    = x[npoints-1];
      y1    = y[0];
      yn    = y[npoints-1];
      nloop = npoints;
      if (optionFill && (xn != x1 || yn != y1)) nloop++;
      npt = 0;
      for (i=1;i<=nloop;i++) {
         if (i > npoints) {
            gxwork[npt] = gxwork[0];  gywork[npt] = gywork[0];
         } else {
            gxwork[npt] = x[i-1];      gywork[npt] = y[i-1];
            npt++;
         }
         if (i == nloop) {
            ComputeLogs(npt, optionZ);
            Int_t bord = gStyle->GetDrawBorder();
            if (optionR) {
               if (optionFill) {
                  gPad->PaintFillArea(npt,gyworkl.data(),gxworkl.data());
                  if (bord) gPad->PaintPolyLine(npt,gyworkl.data(),gxworkl.data());
               }
               if (optionLine) {
                  if (TMath::Abs(theGraph->GetLineWidth())>99) PaintPolyLineHatches(theGraph, npt, gyworkl.data(), gxworkl.data());
                  gPad->PaintPolyLine(npt,gyworkl.data(),gxworkl.data());
               }
            } else {
               if (optionFill) {
                  gPad->PaintFillArea(npt,gxworkl.data(),gyworkl.data());
                  if (bord) gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data());
               }
               if (optionLine) {
                  if (TMath::Abs(theGraph->GetLineWidth())>99) PaintPolyLineHatches(theGraph, npt, gxworkl.data(), gyworkl.data());
                  gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data());
               }
            }
            gxwork[0] = gxwork[npt-1];  gywork[0] = gywork[npt-1];
            npt      = 1;
         }
      }
   }
 
   // Draw the graph with a smooth Curve. Smoothing via Smooth
   if (optionCurve) {
      x1 = x[0];
      xn = x[npoints-1];
      y1 = y[0];
      yn = y[npoints-1];
      drawtype = 1;
      nloop = npoints;
      if (optionCurveFill) {
         drawtype += 1000;
         if (xn != x1 || yn != y1) nloop++;
      }
      if (!optionR) {
         npt = 0;
         for (i=1;i<=nloop;i++) {
            if (i > npoints) {
               gxwork[npt] = gxwork[0];  gywork[npt] = gywork[0];
            } else {
               gxwork[npt] = x[i-1];      gywork[npt] = y[i-1];
               npt++;
            }
            ComputeLogs(npt, optionZ);
            if (gyworkl[npt-1] < rwymin || gyworkl[npt-1] > rwymax) {
               if (npt > 2) {
                  ComputeLogs(npt, optionZ);
                  Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
               }
               gxwork[0] = gxwork[npt-1]; gywork[0] = gywork[npt-1];
               npt=1;
               continue;
            }
         }
         if (npt > 1) {
            ComputeLogs(npt, optionZ);
            Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
         }
      } else {
         drawtype += 10;
         npt    = 0;
         for (i=1;i<=nloop;i++) {
            if (i > npoints) {
               gxwork[npt] = gxwork[0];  gywork[npt] = gywork[0];
            } else {
               if (y[i-1] < minimum || y[i-1] > maximum) continue;
               if (x[i-1] < uxmin    || x[i-1] > uxmax)  continue;
               gxwork[npt] = x[i-1];      gywork[npt] = y[i-1];
               npt++;
            }
            ComputeLogs(npt, optionZ);
            if (gxworkl[npt-1] < rwxmin || gxworkl[npt-1] > rwxmax) {
               if (npt > 2) {
                  ComputeLogs(npt, optionZ);
                  Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
               }
               gxwork[0] = gxwork[npt-1]; gywork[0] = gywork[npt-1];
               npt=1;
               continue;
            }
         }
         if (npt > 1) {
            ComputeLogs(npt, optionZ);
            Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
         }
      }
   }
 
   // Draw the graph with a '*' on every points
   if (optionStar) {
      theGraph->SetMarkerStyle(3);
      npt = 0;
      for (i=1;i<=npoints;i++) {
         gxwork[npt] = x[i-1];      gywork[npt] = y[i-1];
         npt++;
         if (i == npoints) {
            ComputeLogs(npt, optionZ);
            if (optionR)  gPad->PaintPolyMarker(npt,gyworkl.data(),gxworkl.data());
            else          gPad->PaintPolyMarker(npt,gxworkl.data(),gyworkl.data());
            npt = 0;
         }
      }
   }
 
   // Draw the graph with the current polymarker on every points
   if (optionMark) {
      npt = 0;
      for (i=1;i<=npoints;i++) {
         gxwork[npt] = x[i-1];      gywork[npt] = y[i-1];
         npt++;
         if (i == npoints) {
            ComputeLogs(npt, optionZ);
            if (optionR) gPad->PaintPolyMarker(npt,gyworkl.data(),gxworkl.data());
            else         gPad->PaintPolyMarker(npt,gxworkl.data(),gyworkl.data());
            npt = 0;
         }
      }
   }
 
   // Draw the graph as a bar chart
   if (optionBar) {
      Int_t FillSave = theGraph->GetFillColor();
      if(FillSave == gPad->GetFrameFillColor()) {
         // make sure the bars' color is different from the frame background
         if (gPad->GetFrameFillColor()==1) {
            theGraph->SetFillColor(0);
            theGraph->TAttFill::Modify();
         } else {
            theGraph->SetFillColor(1);
            theGraph->TAttFill::Modify();
         }
      }
      if (!optionR) {
         barxmin = x[0];
         barxmax = x[0];
         for (i=1;i<npoints;i++) {
            if (x[i] < barxmin) barxmin = x[i];
            if (x[i] > barxmax) barxmax = x[i];
         }
         bdelta = (barxmax-barxmin)/Double_t(npoints);
      } else {
         barymin = y[0];
         barymax = y[0];
         for (i=1;i<npoints;i++) {
            if (y[i] < barymin) barymin = y[i];
            if (y[i] > barymax) barymax = y[i];
         }
         bdelta = (barymax-barymin)/Double_t(npoints);
      }
      dbar  = 0.5*bdelta*gStyle->GetBarWidth();
      if (!optionR) {
         for (i=1;i<=npoints;i++) {
            xlow  = x[i-1] - dbar;
            xhigh = x[i-1] + dbar;
            yhigh = y[i-1];
            if (xlow  < uxmin && xhigh < uxmin) continue;
            if (xhigh > uxmax && xlow  > uxmax) continue;
            if (xlow  < uxmin) xlow = uxmin;
            if (xhigh > uxmax) xhigh = uxmax;
            if (!optionOne) ylow = TMath::Max((Double_t)0,gPad->GetUymin());
            else            ylow = gPad->GetUymin();
            gxwork[0] = xlow;
            gywork[0] = ylow;
            gxwork[1] = xhigh;
            gywork[1] = yhigh;
            ComputeLogs(2, optionZ);
            if (gyworkl[0] < gPad->GetUymin()) gyworkl[0] = gPad->GetUymin();
            if (gyworkl[1] < gPad->GetUymin()) continue;
            if (gyworkl[1] > gPad->GetUymax()) gyworkl[1] = gPad->GetUymax();
            if (gyworkl[0] > gPad->GetUymax()) continue;
 
            gPad->PaintBox(gxworkl[0],gyworkl[0],gxworkl[1],gyworkl[1]);
         }
      } else {
         for (i=1;i<=npoints;i++) {
            xhigh = x[i-1];
            ylow  = y[i-1] - dbar;
            yhigh = y[i-1] + dbar;
            xlow     = TMath::Max((Double_t)0, gPad->GetUxmin());
            gxwork[0] = xlow;
            gywork[0] = ylow;
            gxwork[1] = xhigh;
            gywork[1] = yhigh;
            ComputeLogs(2, optionZ);
            gPad->PaintBox(gxworkl[0],gyworkl[0],gxworkl[1],gyworkl[1]);
         }
      }
      theGraph->SetFillColor(FillSave);
      theGraph->TAttFill::Modify();
   }
   gPad->ResetBit(TGraph::kClipFrame);
 
   gxwork.clear();
   gywork.clear();
   gxworkl.clear();
   gyworkl.clear();
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// This is a service method used by `THistPainter`
/// to paint 1D histograms. It is not used to paint TGraph.
///
/// Input parameters:
///
/// - npoints : Number of points in X or in Y.
/// - x[npoints] or x[0] : x coordinates or (xmin,xmax).
/// - y[npoints] or y[0] : y coordinates or (ymin,ymax).
/// - chopt : Option.
///
/// The aspect of the histogram is done according to the value of the chopt.
///
/// | Option | Description                                                     |
/// |--------|-----------------------------------------------------------------|
/// |"R"     | Graph is drawn horizontally, parallel to X axis. (default is vertically, parallel to Y axis).If option R is selected the user must give 2 values for Y (y[0]=YMIN and y[1]=YMAX) or N values for X, one for each channel. Otherwise the user must give, N values for Y, one for each channel or 2 values for X (x[0]=XMIN and x[1]=XMAX) |
/// |"L"     | A simple polyline between every points is drawn.|
/// |"H"     | An Histogram with equidistant bins is drawn as a polyline.|
/// |"F"     | An histogram with equidistant bins is drawn as a fill area. Contour is not drawn unless chopt='H' is also selected..|
/// |"N"     | Non equidistant bins (default is equidistant). If N is the number of channels array X and Y must be dimensioned as follow: If option R is not selected (default) then the user must give (N+1) values for X (limits of channels) or N values for Y, one for each channel. Otherwise the user must give (N+1) values for Y (limits of channels). or N values for X, one for each channel |
/// |"F1"    | Idem as 'F' except that fill area base line is the minimum of the pad instead of Y=0.|
/// |"F2"    | Draw a Fill area polyline connecting the center of bins|
/// |"C"     | A smooth Curve is drawn.|
/// |"*"     | A Star is plotted at the center of each bin.|
/// |"P"     | Idem with the current marker.|
/// |"P0"    | Idem with the current marker. Empty bins also drawn.|
/// |"B"     | A Bar chart with equidistant bins is drawn as fill areas (Contours are drawn).|
/// |"]["    | "Cutoff" style. When this option is selected together with H option, the first and last vertical lines of the histogram are not drawn.|
 
void TGraphPainter::PaintGrapHist(TGraph *theGraph, Int_t npoints, const Double_t *x,
                                  const Double_t *y, Option_t *chopt)
{
 
   const char *where = "PaintGrapHist";
 
   Int_t optionLine , optionAxis , optionCurve, optionStar, optionMark;
   Int_t optionBar  , optionRot  , optionOne  , optionOff ;
   Int_t optionFill , optionZ;
   Int_t optionHist , optionBins , optionMarker;
   Int_t i, j, npt;
   Int_t drawtype=0, drawborder, drawbordersav;
   Double_t xlow, xhigh, ylow, yhigh;
   Double_t wmin, wmax;
   Double_t dbar, offset, wminstep;
   Double_t delta = 0;
   Double_t ylast = 0;
   Double_t xi, xi1, xj, xj1, yi1, yi, yj, yj1, xwmin, ywmin;
   Int_t first, last, nbins;
   Int_t fillarea;
 
   char choptaxis[10] = " ";
 
   if (npoints <= 0) {
      Error(where, "illegal number of points (%d)", npoints);
      return;
   }
   TString opt = chopt;
   opt.ToUpper();
   if (opt.Contains("H"))  optionHist = 1;  else optionHist = 0;
   if (opt.Contains("F"))  optionFill = 1;  else optionFill = 0;
   if (opt.Contains("C"))  optionCurve= 1;  else optionCurve= 0;
   if (opt.Contains("*"))  optionStar = 1;  else optionStar = 0;
   if (opt.Contains("R"))  optionRot  = 1;  else optionRot  = 0;
   if (opt.Contains("1"))  optionOne  = 1;  else optionOne  = 0;
   if (opt.Contains("B"))  optionBar  = 1;  else optionBar  = 0;
   if (opt.Contains("N"))  optionBins = 1;  else optionBins = 0;
   if (opt.Contains("L"))  optionLine = 1;  else optionLine = 0;
   if (opt.Contains("P"))  optionMark = 1;  else optionMark = 0;
   if (opt.Contains("A"))  optionAxis = 1;  else optionAxis = 0;
   if (opt.Contains("][")) optionOff  = 1;  else optionOff  = 0;
   if (opt.Contains("P0")) optionMark = 10;
 
   Int_t optionFill2 = 0;
   if (opt.Contains("F") && opt.Contains("2")) {
      optionFill = 0; optionFill2 = 1;
   }
 
   // Set Clipping option
   Option_t *noClip;
   if (theGraph->TestBit(TGraph::kClipFrame)) noClip = "";
   else noClip = "C";
   gPad->SetBit(TGraph::kClipFrame, theGraph->TestBit(TGraph::kClipFrame));
 
   optionZ = 1;
 
   if (optionStar) theGraph->SetMarkerStyle(3);
 
   first = 1;
   last  = npoints;
   nbins = last - first + 1;
 
   //           Draw the Axis with a fixed number of division: 510
 
   Double_t baroffset = gStyle->GetBarOffset();
   Double_t barwidth  = gStyle->GetBarWidth();
   Double_t rwxmin    = gPad->GetUxmin();
   Double_t rwxmax    = gPad->GetUxmax();
   Double_t rwymin    = gPad->GetUymin();
   Double_t rwymax    = gPad->GetUymax();
   Double_t uxmin     = gPad->PadtoX(rwxmin);
   Double_t uxmax     = gPad->PadtoX(rwxmax);
   Double_t rounding  = (uxmax-uxmin)*1.e-5;
   drawborder         = gStyle->GetDrawBorder();
   if (optionAxis) {
      Int_t nx1, nx2, ndivx, ndivy, ndiv;
      choptaxis[0]  = 0;
      Double_t rwmin  = rwxmin;
      Double_t rwmax  = rwxmax;
      ndivx = gStyle->GetNdivisions("X");
      ndivy = gStyle->GetNdivisions("Y");
      if (ndivx > 1000) {
         nx2   = ndivx/100;
         nx1   = TMath::Max(1, ndivx%100);
         ndivx = 100*nx2 + Int_t(Double_t(nx1)*gPad->GetAbsWNDC());
      }
      ndiv  =TMath::Abs(ndivx);
      // coverity [Calling risky function]
      if (ndivx < 0) strlcat(choptaxis, "N",10);
      if (gPad->GetGridx()) {
         // coverity [Calling risky function]
         strlcat(choptaxis, "W",10);
      }
      if (gPad->GetLogx()) {
         rwmin = TMath::Power(10,rwxmin);
         rwmax = TMath::Power(10,rwxmax);
         // coverity [Calling risky function]
         strlcat(choptaxis, "G",10);
      }
      TGaxis axis;
      axis.SetLineColor(gStyle->GetAxisColor("X"));
      axis.SetTextColor(gStyle->GetLabelColor("X"));
      axis.SetTextFont(gStyle->GetLabelFont("X"));
      axis.SetLabelSize(gStyle->GetLabelSize("X"));
      axis.SetLabelOffset(gStyle->GetLabelOffset("X"));
      axis.SetTickSize(gStyle->GetTickLength("X"));
 
      axis.PaintAxis(rwxmin,rwymin,rwxmax,rwymin,rwmin,rwmax,ndiv,choptaxis);
 
      choptaxis[0]  = 0;
      rwmin  = rwymin;
      rwmax  = rwymax;
      if (ndivy < 0) {
         nx2   = ndivy/100;
         nx1   = TMath::Max(1, ndivy%100);
         ndivy = 100*nx2 + Int_t(Double_t(nx1)*gPad->GetAbsHNDC());
         // coverity [Calling risky function]
         strlcat(choptaxis, "N",10);
      }
      ndiv  =TMath::Abs(ndivy);
      if (gPad->GetGridy()) {
         // coverity [Calling risky function]
         strlcat(choptaxis, "W",10);
      }
      if (gPad->GetLogy()) {
         rwmin = TMath::Power(10,rwymin);
         rwmax = TMath::Power(10,rwymax);
         // coverity [Calling risky function]
         strlcat(choptaxis,"G",10);
      }
      axis.SetLineColor(gStyle->GetAxisColor("Y"));
      axis.SetTextColor(gStyle->GetLabelColor("Y"));
      axis.SetTextFont(gStyle->GetLabelFont("Y"));
      axis.SetLabelSize(gStyle->GetLabelSize("Y"));
      axis.SetLabelOffset(gStyle->GetLabelOffset("Y"));
      axis.SetTickSize(gStyle->GetTickLength("Y"));
 
      axis.PaintAxis(rwxmin,rwymin,rwxmin,rwymax,rwmin,rwmax,ndiv,choptaxis);
   }
 
 
   //           Set attributes
   theGraph->TAttLine::Modify();
   theGraph->TAttFill::Modify();
   theGraph->TAttMarker::Modify();
 
   //       Min-Max scope
 
   if (!optionRot) {wmin = x[0];   wmax = x[1];}
   else            {wmin = y[0];   wmax = y[1];}
 
   if (!optionBins) delta = (wmax - wmin)/ Double_t(nbins);
 
   Int_t fwidth = gPad->GetFrameLineWidth();
   TFrame *frame = gPad->GetFrame();
   if (frame) fwidth = frame->GetLineWidth();
   if (optionOff) fwidth = 1;
   Double_t dxframe = gPad->AbsPixeltoX(fwidth/2) - gPad->AbsPixeltoX(0);
   Double_t vxmin = gPad->PadtoX(gPad->GetUxmin() + dxframe);
   Double_t vxmax = gPad->PadtoX(gPad->GetUxmax() - dxframe);
   Double_t dyframe = -gPad->AbsPixeltoY(fwidth/2) + gPad->AbsPixeltoY(0);
   Double_t vymin = gPad->GetUymin() + dyframe; //y already in log scale
   vxmin = TMath::Max(vxmin,wmin);
   vxmax = TMath::Min(vxmax,wmax);
 
   //           Draw the histogram with a fill area
 
   gxwork.resize(2*npoints+10);
   gywork.resize(2*npoints+10);
   gxworkl.resize(2*npoints+10);
   gyworkl.resize(2*npoints+10);
 
   if (optionFill && !optionCurve) {
      fillarea = kTRUE;
      if (!optionRot) {
         gxwork[0] = vxmin;
         if (!optionOne) gywork[0] = TMath::Min(TMath::Max((Double_t)0,gPad->GetUymin())
                                               ,gPad->GetUymax());
         else            gywork[0] = gPad->GetUymin();
         npt = 2;
         for (j=first; j<=last;j++) {
            if (!optionBins) {
               gxwork[npt-1]   = gxwork[npt-2];
               gxwork[npt]     = wmin+((j-first+1)*delta);
               if (gxwork[npt] < gxwork[0]) gxwork[npt] = gxwork[0];
 
            } else {
               xj1 = x[j];      xj  = x[j-1];
               if (xj1 < xj) {
                  if (j != last) Error(where, "X must be in increasing order");
                  else           Error(where, "X must have N+1 values with option N");
                  goto do_cleanup;
               }
               gxwork[npt-1] = x[j-1];       gxwork[npt] = x[j];
            }
            gywork[npt-1] = y[j-1];
            gywork[npt]   = y[j-1];
            if (gywork[npt] < vymin) {gywork[npt] = vymin; gywork[npt-1] = vymin;}
            if ((gxwork[npt-1] >= uxmin-rounding && gxwork[npt-1] <= uxmax+rounding) ||
                (gxwork[npt]   >= uxmin-rounding && gxwork[npt]   <= uxmax+rounding)) npt += 2;
            if (j == last) {
               gxwork[npt-1] = gxwork[npt-2];
               gywork[npt-1] = gywork[0];
               //make sure that the fill area does not overwrite the frame
               //take into account the frame line width
               if (gxwork[0    ] < vxmin) {gxwork[0    ] = vxmin; gxwork[1    ] = vxmin;}
               if (gywork[0] < vymin) {gywork[0] = vymin; gywork[npt-1] = vymin;}
 
               //transform to log ?
               ComputeLogs(npt, optionZ);
               gPad->PaintFillArea(npt,gxworkl.data(),gyworkl.data());
               if (drawborder) {
                  if (!fillarea) gyworkl[0] = ylast;
                  gPad->PaintPolyLine(npt-1,gxworkl.data(),gyworkl.data(),noClip);
               }
               continue;
            }
         }  //endfor (j=first; j<=last;j++) {
      } else {
         gywork[0] = wmin;
         if (!optionOne) gxwork[0] = TMath::Max((Double_t)0,gPad->GetUxmin());
         else            gxwork[0] = gPad->GetUxmin();
         npt = 2;
         for (j=first; j<=last;j++) {
            if (!optionBins) {
               gywork[npt-1] = gywork[npt-2];
               gywork[npt]   = wmin+((j-first+1)*delta);
            } else {
               yj1 = y[j];      yj  = y[j-1];
               if (yj1 < yj) {
                  if (j != last) Error(where, "Y must be in increasing order");
                  else           Error(where, "Y must have N+1 values with option N");
                  return;
               }
               gywork[npt-1] = y[j-1];       gywork[npt] = y[j];
            }
            gxwork[npt-1] = x[j-1];      gxwork[npt] = x[j-1];
            if ((gxwork[npt-1] >= uxmin-rounding && gxwork[npt-1] <= uxmax+rounding) ||
                (gxwork[npt]   >= uxmin-rounding && gxwork[npt]   <= uxmax+rounding)) npt += 2;
            if (j == last) {
               gywork[npt-1] = gywork[npt-2];
               gxwork[npt-1] = gxwork[0];
               ComputeLogs(npt, optionZ);
               gPad->PaintFillArea(npt,gxworkl.data(),gyworkl.data());
               if (drawborder) {
                  if (!fillarea) gyworkl[0] = ylast;
                  gPad->PaintPolyLine(npt-1,gxworkl.data(),gyworkl.data(),noClip);
               }
               continue;
            }
         }  //endfor (j=first; j<=last;j++)
      }
      theGraph->TAttLine::Modify();
      theGraph->TAttFill::Modify();
   }
 
   //      Draw a standard Histogram (default)
 
   if ((optionHist) || !chopt[0]) {
      if (!optionRot) {
         gxwork[0] = wmin;
         if (!optionOne) gywork[0] = TMath::Min(TMath::Max((Double_t)0,gPad->GetUymin())
                                               ,gPad->GetUymax());
         else            gywork[0] = gPad->GetUymin();
         ywmin    = gywork[0];
         npt      = 2;
         for (i=first; i<=last;i++) {
            if (!optionBins) {
               gxwork[npt-1] = gxwork[npt-2];
               gxwork[npt]   = wmin+((i-first+1)*delta);
            } else {
               xi1 = x[i];      xi  = x[i-1];
               if (xi1 < xi) {
                  if (i != last) Error(where, "X must be in increasing order");
                  else           Error(where, "X must have N+1 values with option N");
                  goto do_cleanup;
               }
               gxwork[npt-1] = x[i-1];      gxwork[npt] = x[i];
            }
            gywork[npt-1] = y[i-1];
            gywork[npt]   = y[i-1];
            if (gywork[npt] < vymin) {gywork[npt] = vymin; gywork[npt-1] = vymin;}
            if ((gxwork[npt-1] >= uxmin-rounding && gxwork[npt-1] <= uxmax+rounding) ||
                (gxwork[npt]   >= uxmin-rounding && gxwork[npt]   <= uxmax+rounding)) npt += 2;
            if (i == last) {
               gxwork[npt-1] = gxwork[npt-2];
               gywork[npt-1] = gywork[0];
               //make sure that the fill area does not overwrite the frame
               //take into account the frame line width
               if (gxwork[0] < vxmin) {gxwork[0] = vxmin; gxwork[1    ] = vxmin;}
               if (gywork[0] < vymin) {gywork[0] = vymin; gywork[npt-1] = vymin;}
 
               ComputeLogs(npt, optionZ);
 
               // do not draw the two vertical lines on the edges
               Int_t nbpoints = npt-2;
               Int_t point1  = 1;
 
               if (optionOff) {
                  // remove points before the low cutoff
                  Int_t ip;
                  for (ip=point1; ip<=nbpoints; ip++) {
                     if (gyworkl[ip] != ywmin) {
                        point1 = ip;
                        break;
                     }
                  }
                  // remove points after the high cutoff
                  Int_t point2 = nbpoints;
                  for (ip=point2; ip>=point1; ip--) {
                     if (gyworkl[ip] != ywmin) {
                        point2 = ip;
                        break;
                     }
                  }
                  nbpoints = point2-point1+1;
               } else {
                  // if the 1st or last bin are not on the pad limits the
                  // the two vertical lines on the edges are added.
                  if (gxwork[0] > gPad->GetUxmin()) { nbpoints++; point1 = 0; }
                  if (gxwork[nbpoints] < gPad->GetUxmax()) nbpoints++;
               }
 
               gPad->PaintPolyLine(nbpoints,gxworkl.data() + point1, gyworkl.data() + point1, noClip);
               continue;
            }
         }  //endfor (i=first; i<=last;i++)
      } else {
         gywork[0] = wmin;
         if (!optionOne) gxwork[0] = TMath::Max((Double_t)0,gPad->GetUxmin());
         else            gxwork[0] = gPad->GetUxmin();
         xwmin    = gxwork[0];
         npt      = 2;
         for (i=first; i<=last;i++) {
            if (!optionBins) {
               gywork[npt-1]   = gywork[npt-2];
               gywork[npt] = wmin+((i-first+1)*delta);
            } else {
               yi1 = y[i];      yi  = y[i-1];
               if (yi1 < yi) {
                  if (i != last) Error(where, "Y must be in increasing order");
                  else           Error(where, "Y must have N+1 values with option N");
                  goto do_cleanup;
               }
               gywork[npt-1] = y[i-1];      gywork[npt] = y[i];
            }
            gxwork[npt-1] = x[i-1];      gxwork[npt] = x[i-1];
            if ((gxwork[npt-1] >= uxmin-rounding && gxwork[npt-1] <= uxmax+rounding) ||
                (gxwork[npt]   >= uxmin-rounding && gxwork[npt]   <= uxmax+rounding)) npt += 2;
            if (i == last) {
               gywork[npt-1] = gywork[npt-2];
               gxwork[npt-1] = xwmin;
               ComputeLogs(npt, optionZ);
               gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data(),noClip);
               continue;
            }
         }  //endfor (i=first; i<=last;i++)
      }
   }
 
   //              Draw the histogram with a smooth Curve.
   //              The smoothing is done by the method Smooth()
 
   if (optionCurve) {
      if (!optionFill) {
         drawtype = 1;
      } else {
         if (!optionOne) drawtype = 2;
         else            drawtype = 3;
      }
      if (!optionRot) {
         npt = 0;
         for (i=first; i<=last;i++) {
            npt++;
            if (!optionBins) {
               gxwork[npt-1] = wmin+(i-first)*delta+0.5*delta;
            } else {
               xi1 = x[i];      xi  = x[i-1];
               if (xi1 < xi) {
                  if (i != last) Error(where, "X must be in increasing order");
                  else           Error(where, "X must have N+1 values with option N");
                  goto do_cleanup;
               }
               gxwork[npt-1] = x[i-1] + 0.5*(x[i]-x[i-1]);
            }
            if (gxwork[npt-1] < uxmin || gxwork[npt-1] > uxmax) {
               npt--;
               continue;
            }
            gywork[npt-1] = y[i-1];
            ComputeLogs(npt, optionZ);
            if ((gyworkl[npt-1] < rwymin) || (gyworkl[npt-1] > rwymax)) {
               if (npt > 2) {
                  ComputeLogs(npt, optionZ);
                  Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
               }
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt      = 1;
               continue;
            }
            if (npt >= fgMaxPointsPerLine) {
               ComputeLogs(fgMaxPointsPerLine, optionZ);
               Smooth(theGraph, fgMaxPointsPerLine,gxworkl.data(),gyworkl.data(),drawtype);
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt      = 1;
            }
         }  //endfor (i=first; i<=last;i++)
         if (npt > 1) {
            ComputeLogs(npt, optionZ);
            Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
         }
      } else {
         drawtype = drawtype+10;
         npt   = 0;
         for (i=first; i<=last;i++) {
            npt++;
            if (!optionBins) {
               gywork[npt-1] = wmin+(i-first)*delta+0.5*delta;
            } else {
               yi1 = y[i];      yi = y[i-1];
               if (yi1 < yi) {
                  if (i != last) Error(where, "Y must be in increasing order");
                  else           Error(where, "Y must have N+1 values with option N");
                  return;
               }
               gywork[npt-1] = y[i-1] + 0.5*(y[i]-y[i-1]);
            }
            gxwork[npt-1] = x[i-1];
            ComputeLogs(npt, optionZ);
            if ((gxworkl[npt] < uxmin) || (gxworkl[npt] > uxmax)) {
               if (npt > 2) {
                  ComputeLogs(npt, optionZ);
                  Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
               }
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt      = 1;
               continue;
            }
            if (npt >= fgMaxPointsPerLine) {
               ComputeLogs(fgMaxPointsPerLine, optionZ);
               Smooth(theGraph, fgMaxPointsPerLine,gxworkl.data(),gyworkl.data(),drawtype);
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt      = 1;
            }
         }  //endfor (i=first; i<=last;i++)
         if (npt > 1) {
            ComputeLogs(npt, optionZ);
            Smooth(theGraph, npt,gxworkl.data(),gyworkl.data(),drawtype);
         }
      }
   }
 
   //    Draw the histogram with a simple line
 
   if (optionLine) {
      gPad->SetBit(TGraph::kClipFrame);
      wminstep = wmin + 0.5*delta;
      Axis_t ax1,ax2,ay1,ay2;
      gPad->GetRangeAxis(ax1,ay1,ax2,ay2);
 
      if (!optionRot) {
         npt = 0;
         for (i=first; i<=last;i++) {
            npt++;
            if (!optionBins) {
               gxwork[npt-1] = wmin+(i-first)*delta+0.5*delta;
            } else {
               xi1 = x[i];      xi = x[i-1];
               if (xi1 < xi) {
                  if (i != last) Error(where, "X must be in increasing order");
                  else           Error(where, "X must have N+1 values with option N");
                  return;
               }
               gxwork[npt-1] = x[i-1] + 0.5*(x[i]-x[i-1]);
            }
            if (gxwork[npt-1] < uxmin || gxwork[npt-1] > uxmax) { npt--; continue;}
            gywork[npt-1] = y[i-1];
            gywork[npt]   = y[i-1]; //new
            if ((gywork[npt-1] < rwymin) || ((gywork[npt-1] > rwymax) && !optionFill2)) {
               if (npt > 2) {
                  ComputeLogs(npt, optionZ);
                  gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data());
               }
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt       = 1;
               continue;
            }
 
            if (npt >= fgMaxPointsPerLine) {
               if (optionLine) {
                  ComputeLogs(fgMaxPointsPerLine, optionZ);
                  if (optionFill2) {
                     gxworkl[npt]   = gxworkl[npt-1]; gyworkl[npt]   = rwymin;
                     gxworkl[npt+1] = gxworkl[0];     gyworkl[npt+1] = rwymin;
                     gPad->PaintFillArea(fgMaxPointsPerLine+2,gxworkl.data(),gyworkl.data());
                  }
                  gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data());
               }
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt      = 1;
            }
         }  //endfor (i=first; i<=last;i++)
         if (npt > 1) {
            ComputeLogs(npt, optionZ);
            if (optionFill2) {
               gxworkl[npt]   = gxworkl[npt-1]; gyworkl[npt]   = rwymin;
               gxworkl[npt+1] = gxworkl[0];     gyworkl[npt+1] = rwymin;
               gPad->PaintFillArea(npt+2,gxworkl.data(),gyworkl.data());
            }
            gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data());
         }
      } else {
         npt = 0;
         for (i=first; i<=last;i++) {
            npt++;
            if (!optionBins) {
               gywork[npt-1] = wminstep+(i-first)*delta+0.5*delta;
            } else {
               yi1 = y[i];      yi = y[i-1];
               if (yi1 < yi) {
                  if (i != last) Error(where, "Y must be in increasing order");
                  else           Error(where, "Y must have N+1 values with option N");
                  goto do_cleanup;
               }
               gywork[npt-1] = y[i-1] + 0.5*(y[i]-y[i-1]);
            }
            gxwork[npt-1] = x[i-1];
            if ((gxwork[npt-1] < uxmin) || (gxwork[npt-1] > uxmax)) {
               if (npt > 2) {
                  if (optionLine) {
                     ComputeLogs(npt, optionZ);
                     gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data(),noClip);
                  }
               }
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt      = 1;
               continue;
            }
            if (npt >= fgMaxPointsPerLine) {
               if (optionLine) {
                  ComputeLogs(fgMaxPointsPerLine, optionZ);
                  gPad->PaintPolyLine(fgMaxPointsPerLine,gxworkl.data(),gyworkl.data());
               }
               gxwork[0] = gxwork[npt-1];
               gywork[0] = gywork[npt-1];
               npt      = 1;
            }
         }  //endfor (i=first; i<=last;i++)
         if (optionLine != 0 && npt > 1) {
            ComputeLogs(npt, optionZ);
            gPad->PaintPolyLine(npt,gxworkl.data(),gyworkl.data(),noClip);
         }
      }
   }
 
   //              Draw the histogram as a bar chart
 
   if (optionBar) {
      if (!optionBins) {
         offset = delta*baroffset; dbar = delta*barwidth;
      } else {
         if (!optionRot) {
            offset = (x[1]-x[0])*baroffset;
            dbar   = (x[1]-x[0])*barwidth;
         } else {
            offset = (y[1]-y[0])*baroffset;
            dbar   = (y[1]-y[0])*barwidth;
         }
      }
      drawbordersav = drawborder;
      gStyle->SetDrawBorder(1);
      if (!optionRot) {
         xlow  = wmin+offset;
         xhigh = wmin+offset+dbar;
         if (!optionOne) ylow = TMath::Min(TMath::Max((Double_t)0,gPad->GetUymin())
                                ,gPad->GetUymax());
         else            ylow = gPad->GetUymin();
 
         for (i=first; i<=last;i++) {
            yhigh    = y[i-1];
            gxwork[0] = xlow;
            gywork[0] = ylow;
            gxwork[1] = xhigh;
            gywork[1] = yhigh;
            ComputeLogs(2, optionZ);
            if (xlow < rwxmax && xhigh > rwxmin)
               gPad->PaintBox(gxworkl[0],gyworkl[0],gxworkl[1],gyworkl[1]);
            if (!optionBins) {
               xlow  = xlow+delta;
               xhigh = xhigh+delta;
            } else {
               if (i < last) {
                  xi1 = x[i];      xi = x[i-1];
                  if (xi1 < xi) {
                     Error(where, "X must be in increasing order");
                     goto do_cleanup;
                  }
                  offset  = (x[i+1]-x[i])*baroffset;
                  dbar    = (x[i+1]-x[i])*barwidth;
                  xlow    = x[i] + offset;
                  xhigh   = x[i] + offset + dbar;
               }
            }
         }  //endfor (i=first; i<=last;i++)
      } else {
         ylow  = wmin + offset;
         yhigh = wmin + offset + dbar;
         if (!optionOne) xlow = TMath::Max((Double_t)0,gPad->GetUxmin());
         else            xlow = gPad->GetUxmin();
         for (i=first; i<=last;i++) {
            xhigh    = x[i-1];
            gxwork[0] = xlow;
            gywork[0] = ylow;
            gxwork[1] = xhigh;
            gywork[1] = yhigh;
            ComputeLogs(2, optionZ);
            gPad->PaintBox(gxworkl[0],gyworkl[0],gxworkl[1],gyworkl[1]);
            gPad->PaintBox(xlow,ylow,xhigh,yhigh);
            if (!optionBins) {
               ylow  = ylow  + delta;
               yhigh = yhigh + delta;
            } else {
               if (i < last) {
                  yi1 = y[i];      yi = y[i-1];
                  if (yi1 < yi) {
                     Error(where, "Y must be in increasing order");
                     goto do_cleanup;
                  }
                  offset  = (y[i+1]-y[i])*baroffset;
                  dbar    = (y[i+1]-y[i])*barwidth;
                  ylow    = y[i] + offset;
                  yhigh   = y[i] + offset + dbar;
               }
            }
         }  //endfor (i=first; i<=last;i++)
      }
      gStyle->SetDrawBorder(drawbordersav);
   }
 
   //    Draw the histogram with a simple marker
 
   optionMarker = 0;
   if ((optionStar) || (optionMark)) optionMarker=1;
 
   if (optionMarker) {
      Double_t xm,ym;
      npt = 0;
      if (!optionRot) {
         for (i=first; i<=last;i++) {
            if (!optionBins) xm = wmin+(i-first)*delta+0.5*delta;
            else             xm = x[i-1] + 0.5*(x[i]-x[i-1]);
            ym                  = y[i-1];
            if (optionMark != 10) {
               if (ym<rwymax && ym > rwymin) {
                  npt++;
                  gxwork[npt-1] = xm;
                  gywork[npt-1] = ym;
               }
            } else {
               if (ym<rwymax && ym >= rwymin) {
                  npt++;
                  gxwork[npt-1] = xm;
                  gywork[npt-1] = ym;
               }
            }
            if (npt >= fgMaxPointsPerLine) {
               ComputeLogs(npt, optionZ);
               gPad->PaintPolyMarker(npt,gxworkl.data(),gyworkl.data());
               npt = 0;
            }
         }
         if (npt > 0) {
            ComputeLogs(npt, optionZ);
            gPad->PaintPolyMarker(npt,gxworkl.data(),gyworkl.data());
         }
      } else {
         wminstep = wmin + 0.5*delta;
         for (i=first; i<=last;i++) {
            if (!optionBins) ym = wminstep+(i-first)*delta+0.5*delta;
            else             ym = y[i-1] + 0.5*(y[i]-y[i-1]);
            xm                  = x[i-1];
            if (optionMark != 10) {
               if (xm<rwxmax && xm > rwxmin) {
                  npt++;
                  gxwork[npt-1] = xm;
                  gywork[npt-1] = ym;
               }
            } else {
               if (xm<rwxmax && xm >= rwxmin) {
                  npt++;
                  gxwork[npt-1] = xm;
                  gywork[npt-1] = ym;
               }
            }
            if (npt >= fgMaxPointsPerLine) {
               ComputeLogs(npt, optionZ);
               gPad->PaintPolyMarker(npt,gxworkl.data(),gyworkl.data());
               npt = 0;
            }
         }
         if (npt > 0) {
            ComputeLogs(npt, optionZ);
            gPad->PaintPolyMarker(npt,gxworkl.data(),gyworkl.data());
         }
      }
   }
 
   gPad->ResetBit(TGraph::kClipFrame);
 
do_cleanup:
   gxwork.clear();
   gywork.clear();
   gxworkl.clear();
   gyworkl.clear();
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// [Paint this TGraphAsymmErrors with its current attributes.](\ref GrP3)
 
void TGraphPainter::PaintGraphAsymmErrors(TGraph *theGraph, Option_t *option)
{
 
   std::vector<Double_t> xline, yline;
   Int_t if1 = 0;
   Int_t if2 = 0;
   Double_t xb[4], yb[4];
 
   const Int_t kBASEMARKER=8;
   static Float_t cxx[30] = {1.0,1.0,0.5,0.5,1.0,1.0,0.5,0.6,1.0,0.5,0.5,1.0,0.5,0.6,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   static Float_t cyy[30] = {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.5,0.5,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   Int_t theNpoints = theGraph->GetN();
   Double_t *theX  = theGraph->GetX();
   Double_t *theY  = theGraph->GetY();
   Double_t *theEXlow  = theGraph->GetEXlow();  if (!theEXlow) return;
   Double_t *theEYlow  = theGraph->GetEYlow();  if (!theEYlow) return;
   Double_t *theEXhigh = theGraph->GetEXhigh(); if (!theEXhigh) return;
   Double_t *theEYhigh = theGraph->GetEYhigh(); if (!theEYhigh) return;
 
   if (strchr(option,'X') || strchr(option,'x')) {PaintGraphSimple(theGraph, option); return;}
   Bool_t brackets = kFALSE;
   Bool_t braticks = kFALSE;
   if (strstr(option,"||") || strstr(option,"[]")) {
      brackets = kTRUE;
      if (strstr(option,"[]")) braticks = kTRUE;
   }
   Bool_t endLines = kTRUE;
   if (strchr(option,'z')) endLines = kFALSE;
   if (strchr(option,'Z')) endLines = kFALSE;
   const char *arrowOpt = nullptr;
   if (strchr(option,'>'))  arrowOpt = ">";
   if (strstr(option,"|>")) arrowOpt = "|>";
 
   Bool_t axis = kFALSE;
   if (strchr(option,'a')) axis = kTRUE;
   if (strchr(option,'A')) axis = kTRUE;
   if (axis) PaintGraphSimple(theGraph, option);
 
   Bool_t option0 = kFALSE;
   Bool_t option2 = kFALSE;
   Bool_t option3 = kFALSE;
   Bool_t option4 = kFALSE;
   Bool_t option5 = kFALSE;
   if (strchr(option,'0')) option0 = kTRUE;
   if (strchr(option,'2')) option2 = kTRUE;
   if (strchr(option,'3')) option3 = kTRUE;
   if (strchr(option,'4')) {option3 = kTRUE; option4 = kTRUE;}
   if (strchr(option,'5')) {option2 = kTRUE; option5 = kTRUE;}
 
   // special flags in case of "reverse plot" and "log scale"
   Bool_t xrevlog = kFALSE;
   Bool_t yrevlog = kFALSE;
   if (strstr(option,"-N")) xrevlog = kTRUE; // along X
   if (strstr(option,"-M")) yrevlog = kTRUE; // along Y
 
   if (option3) {
      xline.resize(2*theNpoints);
      yline.resize(2*theNpoints);
      if (xline.empty() || yline.empty()) {
         Error("PaintGraphAsymmErrors", "too many points, out of memory");
         return;
      }
      if1 = 1;
      if2 = 2*theNpoints;
   }
 
   theGraph->TAttLine::Modify();
 
   TArrow arrow;
   arrow.SetLineWidth(theGraph->GetLineWidth());
   arrow.SetLineColor(theGraph->GetLineColor());
   arrow.SetFillColor(theGraph->GetFillColor());
 
   TBox box;
   Double_t x1b,y1b,x2b,y2b;
   box.SetLineWidth(theGraph->GetLineWidth());
   box.SetLineColor(theGraph->GetLineColor());
   box.SetFillColor(theGraph->GetFillColor());
   box.SetFillStyle(theGraph->GetFillStyle());
 
   Double_t symbolsize = theGraph->GetMarkerSize();
   Double_t sbase = symbolsize*kBASEMARKER;
   Int_t mark  = TAttMarker::GetMarkerStyleBase(theGraph->GetMarkerStyle());
   Double_t cx  = 0;
   Double_t cy  = 0;
   if (mark >= 20 && mark <= 49) {
      cx = cxx[mark-20];
      cy = cyy[mark-20];
   }
 
   // Define the offset of the error bars due to the symbol size
   Double_t s2x  =  gPad->PixeltoX(Int_t(0.5*sbase)) - gPad->PixeltoX(0);
   Double_t s2y  = -gPad->PixeltoY(Int_t(0.5*sbase)) + gPad->PixeltoY(0);
   Int_t dxend   = Int_t(gStyle->GetEndErrorSize());
   Double_t tx   =  gPad->PixeltoX(dxend) - gPad->PixeltoX(0);
   Double_t ty   = -gPad->PixeltoY(dxend) + gPad->PixeltoY(0);
   Float_t asize = 0.6*symbolsize*kBASEMARKER/gPad->GetWh();
 
   gPad->SetBit(TGraph::kClipFrame, theGraph->TestBit(TGraph::kClipFrame));
 
   // loop over all the graph points
   Double_t x, y, exl, exh, eyl, eyh, xl1, xl2, xr1, xr2, yup1, yup2, ylow1, ylow2;
   for (Int_t i=0;i<theNpoints;i++) {
      x  = gPad->XtoPad(theX[i]);
      y  = gPad->YtoPad(theY[i]);
 
      if (!option0) {
         if (option3) {
            if (x < gPad->GetUxmin()) x = gPad->GetUxmin();
            if (x > gPad->GetUxmax()) x = gPad->GetUxmax();
            if (y < gPad->GetUymin()) y = gPad->GetUymin();
            if (y > gPad->GetUymax()) y = gPad->GetUymax();
         } else {
            if (x < gPad->GetUxmin()) continue;
            if (x > gPad->GetUxmax()) continue;
            if (y < gPad->GetUymin()) continue;
            if (y > gPad->GetUymax()) continue;
         }
      }
      exl = theEXlow[i];
      exh = theEXhigh[i];
      eyl = theEYlow[i];
      eyh = theEYhigh[i];
 
      if (xrevlog) {
         xl1 = x + s2x*cx;
         xl2 = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               - exh);
         xr1 = x - s2x*cx;
         xr2 = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               + exl);
         tx = -tx;
      } else {
         xl1 = x - s2x*cx;
         xl2 = gPad->XtoPad(theX[i] - exl);
         xr1 = x + s2x*cx;
         xr2 = gPad->XtoPad(theX[i] + exh);
      }
 
      if (yrevlog) {
         yup1 = y - s2y*cy;
         yup2 = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               + eyl);
         ylow1 = y + s2y*cy;
         ylow2 = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               - eyh);
      } else {
         yup1  = y + s2y*cy;
         yup2  = gPad->YtoPad(theY[i] + eyh);
         ylow1 = y - s2y*cy;
         ylow2 = gPad->YtoPad(theY[i] - eyl);
      }
      if (yup2 > gPad->GetUymax()) yup2 =  gPad->GetUymax();
      if (ylow2 < gPad->GetUymin()) ylow2 =  gPad->GetUymin();
 
      //  draw the error rectangles
      if (option2) {
         x1b = xl2;
         y1b = ylow2;
         x2b = xr2;
         y2b = yup2;
         if (x1b < gPad->GetUxmin()) x1b = gPad->GetUxmin();
         if (x1b > gPad->GetUxmax()) x1b = gPad->GetUxmax();
         if (y1b < gPad->GetUymin()) y1b = gPad->GetUymin();
         if (y1b > gPad->GetUymax()) y1b = gPad->GetUymax();
         if (x2b < gPad->GetUxmin()) x2b = gPad->GetUxmin();
         if (x2b > gPad->GetUxmax()) x2b = gPad->GetUxmax();
         if (y2b < gPad->GetUymin()) y2b = gPad->GetUymin();
         if (y2b > gPad->GetUymax()) y2b = gPad->GetUymax();
         if (option5) box.PaintBox(x1b, y1b, x2b, y2b, "l");
         else         box.PaintBox(x1b, y1b, x2b, y2b);
         continue;
      }
 
      //  keep points for fill area drawing
      if (option3) {
         xline[if1-1] = x;
         xline[if2-1] = x;
         yline[if1-1] = yup2;
         yline[if2-1] = ylow2;
         if1++;
         if2--;
         continue;
      }
 
      if (exl != 0. || exh != 0.) {
         if (arrowOpt) {
            if (exl != 0.) arrow.PaintArrow(xl1,y,xl2,y,asize,arrowOpt);
            if (exh != 0.) arrow.PaintArrow(xr1,y,xr2,y,asize,arrowOpt);
         } else {
            if (!brackets) {
               if (exl != 0.) gPad->PaintLine(xl1,y,xl2,y);
               if (exh != 0.) gPad->PaintLine(xr1,y,xr2,y);
            }
            if (endLines) {
               if (braticks) {
                  if (exl != 0.) {
                     xb[0] = xl2+tx; yb[0] = y-ty;
                     xb[1] = xl2;    yb[1] = y-ty;
                     xb[2] = xl2;    yb[2] = y+ty;
                     xb[3] = xl2+tx; yb[3] = y+ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
                  if (exh != 0.) {
                     xb[0] = xr2-tx; yb[0] = y-ty;
                     xb[1] = xr2;    yb[1] = y-ty;
                     xb[2] = xr2;    yb[2] = y+ty;
                     xb[3] = xr2-tx; yb[3] = y+ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
               } else {
                  gPad->PaintLine(xl2,y-ty,xl2,y+ty);
                  gPad->PaintLine(xr2,y-ty,xr2,y+ty);
               }
            }
         }
      }
 
      if (eyl != 0. || eyh != 0.) {
         if (arrowOpt) {
            if (eyh != 0.) arrow.PaintArrow(x,yup1,x,yup2,asize,arrowOpt);
            if (eyl != 0.) arrow.PaintArrow(x,ylow1,x,ylow2,asize,arrowOpt);
         } else {
            if (!brackets) {
               if (eyh != 0.) gPad->PaintLine(x,yup1,x,yup2);
               if (eyl != 0.) gPad->PaintLine(x,ylow1,x,ylow2);
            }
            if (endLines) {
               if (braticks) {
                  if (eyh != 0.) {
                     xb[0] = x-tx; yb[0] = yup2-ty;
                     xb[1] = x-tx; yb[1] = yup2;
                     xb[2] = x+tx; yb[2] = yup2;
                     xb[3] = x+tx; yb[3] = yup2-ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
                  if (eyl != 0.) {
                     xb[0] = x-tx; yb[0] = ylow2+ty;
                     xb[1] = x-tx; yb[1] = ylow2;
                     xb[2] = x+tx; yb[2] = ylow2;
                     xb[3] = x+tx; yb[3] = ylow2+ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
               } else {
                  if (eyh != 0.) gPad->PaintLine(x-tx,yup2,x+tx,yup2);
                  if (eyl != 0.) gPad->PaintLine(x-tx,ylow2,x+tx,ylow2);
               }
            }
         }
      }
   }
   if (!brackets && !axis) PaintGraphSimple(theGraph, option);
   gPad->ResetBit(TGraph::kClipFrame);
 
   if (option3) {
      Int_t logx = gPad->GetLogx();
      Int_t logy = gPad->GetLogy();
      gPad->SetLogx(0);
      gPad->SetLogy(0);
      if (option4) PaintGraph(theGraph, 2*theNpoints, xline.data(), yline.data(),"FC");
      else         PaintGraph(theGraph, 2*theNpoints, xline.data(), yline.data(),"F");
      gPad->SetLogx(logx);
      gPad->SetLogy(logy);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// [Paint this TGraphMultiErrors with its current attributes.](\ref GrP3)
 
void TGraphPainter::PaintGraphMultiErrors(TGraph *theGraph, Option_t *option)
{
   if (!theGraph->InheritsFrom(TGraphMultiErrors::Class())) {
      PaintHelper(theGraph, option);
      return;
   }
 
   auto tg = (TGraphMultiErrors *)theGraph;
 
   Int_t NYErrors = tg->GetNYErrors();
   if (NYErrors <= 0) {
      PaintGraphSimple(tg, option);
      return;
   }
 
   TString tsOpt = option;
   tsOpt.ToLower();
 
   std::vector<TString> options(NYErrors + 1);
   Int_t filled = 0;
 
   if (tsOpt.CountChar(';') < NYErrors) {
      options[0] = tsOpt.Contains(";") ? tsOpt(0, tsOpt.First(';')) : tsOpt.Copy();
      filled++;
   }
 
   Ssiz_t firstSemicolon;
   while ((firstSemicolon = tsOpt.First(';')) != kNPOS && filled <= NYErrors) {
      options[filled] = tsOpt(0, firstSemicolon);
      tsOpt = tsOpt(firstSemicolon + 1, tsOpt.Length());
      filled++;
   }
 
   if (filled <= NYErrors) {
      options[filled] = tsOpt.Copy();
      filled++;
   }
 
   for (Int_t i = filled; i <= NYErrors; i++)
      options[i] = "";
 
   std::vector<Double_t> xline;
   std::vector<std::vector<Double_t>> yline(NYErrors);
   Int_t if1 = 0;
   Int_t if2 = 0;
   Double_t xb[4], yb[4];
 
   const Int_t kBASEMARKER = 8;
   static Float_t cxx[30] = {1.0,1.0,0.5,0.5,1.0,1.0,0.5,0.6,1.0,0.5,0.5,1.0,0.5,0.6,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   static Float_t cyy[30] = {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.5,0.5,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   Int_t theNpoints = tg->GetN();
   Double_t *theX = tg->GetX();
   Double_t *theY = tg->GetY();
   Double_t *theExL = tg->GetEXlow();
   Double_t *theExH = tg->GetEXhigh();
   std::vector<Double_t *> theEyL(NYErrors);
   std::vector<Double_t *> theEyH(NYErrors);
 
   Bool_t theEyExists = kTRUE;
   for (Int_t j = 0; j < NYErrors; j++) {
      theEyL[j] = tg->GetEYlow(j);
      theEyH[j] = tg->GetEYhigh(j);
      theEyExists &= (theEyL[j] && theEyH[j]);
   }
 
   if (!theX || !theY || !theExL || !theExH || !theEyExists)
      return;
 
   std::vector<Bool_t> DrawErrors(NYErrors);
   Bool_t AnyErrors = kFALSE;
   Bool_t NoErrorsX = kTRUE;
   Bool_t Option0X = kFALSE;
   Bool_t DrawMarker = kFALSE;
   std::vector<Bool_t> Braticks(NYErrors);
   std::vector<Bool_t> Brackets(NYErrors);
   std::vector<Bool_t> EndLines(NYErrors);
   std::vector<Char_t *> ArrowOpt(NYErrors);
   std::vector<Bool_t> Option5(NYErrors);
   std::vector<Bool_t> Option4(NYErrors);
   std::vector<Bool_t> Option3(NYErrors);
   Bool_t AnyOption3 = kFALSE;
   std::vector<Bool_t> Option2(NYErrors);
   std::vector<Bool_t> Option0(NYErrors);
   Bool_t AnyOption0 = kFALSE;
   std::vector<Double_t> Scale(NYErrors);
 
   const TRegexp ScaleRegExp("s=*[0-9]\\.*[0-9]");
 
   for (Int_t j = 0; j < NYErrors; j++) {
      if (options[j + 1].Contains("s=")) {
         sscanf(strstr(options[j + 1].Data(), "s="), "s=%lf", &Scale[j]);
         options[j + 1].ReplaceAll(options[j + 1](ScaleRegExp), "");
      } else
         Scale[j] = 1.;
 
      DrawErrors[j] = !options[j + 1].Contains("x");
      AnyErrors |= DrawErrors[j];
      Braticks[j] = options[j + 1].Contains("[]");
      Brackets[j] = options[j + 1].Contains("||") || Braticks[j];
      EndLines[j] = !options[j + 1].Contains("z");
 
      if (options[j + 1].Contains("|>"))
         ArrowOpt[j] = (Char_t *)"|>";
      else if (options[j + 1].Contains(">"))
         ArrowOpt[j] = (Char_t *)">";
      else
         ArrowOpt[j] = nullptr;
 
      Option5[j] = options[j + 1].Contains("5");
      Option4[j] = options[j + 1].Contains("4");
      Option3[j] = options[j + 1].Contains("3") || Option4[j];
      AnyOption3 |= Option3[j];
      Option2[j] = options[j + 1].Contains("2") || Option5[j];
      Option0[j] = options[j + 1].Contains("0");
      AnyOption0 |= Option0[j];
 
      NoErrorsX &= (Option3[j] || Option2[j]);
      Option0X |= !(Option3[j] || Option2[j]) && Option0[j];
      DrawMarker |= !(Brackets[j] || Option3[j] || Option2[j]);
   }
 
   Bool_t Draw0PointsX = !options[0].Contains("x0") && (gPad->GetLogx() == 0);
   Bool_t Draw0PointsY = !options[0].Contains("y0") && (gPad->GetLogy() == 0);
   options[0].ReplaceAll("x0", "");
   options[0].ReplaceAll("y0", "");
 
   Bool_t DrawErrorsX = !options[0].Contains("x");
   Bool_t BraticksX = options[0].Contains("[]");
   Bool_t BracketsX = options[0].Contains("||") || BraticksX;
   Bool_t EndLinesX = !options[0].Contains("z");
 
   Char_t *ArrowOptX = nullptr;
   if (options[0].Contains("|>"))
      ArrowOptX = (Char_t *)"|>";
   else if (options[0].Contains(">"))
      ArrowOptX = (Char_t *)">";
 
   Double_t ScaleX = 1.;
   if (options[0].Contains("s=")) {
      sscanf(strstr(options[0].Data(), "s="), "s=%lf", &ScaleX);
      options[0].ReplaceAll(options[0](ScaleRegExp), "");
   }
 
   if (!AnyErrors && !DrawErrorsX) {
      PaintGraphSimple(tg, options[0].Data());
      return;
   }
 
   Bool_t DrawAxis = options[0].Contains("a");
   Bool_t IndividualStyles = options[0].Contains("s");
 
   if (DrawAxis)
      PaintGraphSimple(tg, options[0].Data());
 
   Int_t NPointsInside = AnyOption0 ? theNpoints : 0;
 
   Double_t x,y;
   for (Int_t i = 0; i < theNpoints && !AnyOption0; i++) {
      x = gPad->XtoPad(theX[i]);
      y = gPad->YtoPad(theY[i]);
 
      if ((x >= gPad->GetUxmin()) && (x <= gPad->GetUxmax()) && (y >= gPad->GetUymin()) && (y <= gPad->GetUymax()) &&
          (Draw0PointsX || theX[i] != 0.) && (Draw0PointsY || theY[i] != 0.))
         NPointsInside++;
   }
 
   if (AnyOption3) {
      xline.resize(2 * NPointsInside);
 
      if (xline.empty()) {
         Error("PaintGraphMultiErrors", "too many points, out of memory");
         return;
      }
 
      if1 = 1;
      if2 = 2 * NPointsInside;
   }
 
   for (Int_t j = 0; j < NYErrors; j++) {
      if (Option3[j] && DrawErrors[j]) {
         yline[j].resize(2 * NPointsInside);
 
         if (yline[j].empty()) {
            Error("PaintGraphMultiErrors", "too many points, out of memory");
            return;
         }
      }
   }
 
   tg->TAttLine::Modify();
 
   TArrow arrow;
   arrow.SetLineWidth(tg->GetLineWidth());
   arrow.SetLineColor(tg->GetLineColor());
   arrow.SetFillColor(tg->GetFillColor());
 
   TBox box;
   Double_t x1b, y1b, x2b, y2b;
   box.SetLineWidth(tg->GetLineWidth());
   box.SetLineColor(tg->GetLineColor());
   box.SetFillColor(tg->GetFillColor());
   box.SetFillStyle(tg->GetFillStyle());
 
   Double_t symbolsize = tg->GetMarkerSize();
   Double_t sbase = symbolsize * kBASEMARKER;
   Int_t mark = TAttMarker::GetMarkerStyleBase(tg->GetMarkerStyle());
   Double_t cx = 0.;
   Double_t cy = 0.;
 
   if (mark >= 20 && mark <= 49) {
      cx = cxx[mark - 20];
      cy = cyy[mark - 20];
   }
 
   // Define the offset of the error bars due to the symbol size
   Double_t s2x = gPad->PixeltoX(Int_t(0.5 * sbase)) - gPad->PixeltoX(0);
   Double_t s2y = -gPad->PixeltoY(Int_t(0.5 * sbase)) + gPad->PixeltoY(0);
   auto dxend = Int_t(gStyle->GetEndErrorSize());
   Double_t tx = gPad->PixeltoX(dxend) - gPad->PixeltoX(0);
   Double_t ty = -gPad->PixeltoY(dxend) + gPad->PixeltoY(0);
   Float_t asize = 0.6 * symbolsize * kBASEMARKER / gPad->GetWh();
 
   gPad->SetBit(TGraph::kClipFrame, tg->TestBit(TGraph::kClipFrame));
 
   // loop over all the graph points
   Double_t xl1, xl2, xr1, xr2, yup1, yup2, ylow1, ylow2;
   for (Int_t i = 0; i < theNpoints; i++) {
      x = gPad->XtoPad(theX[i]);
      y = gPad->YtoPad(theY[i]);
 
      Bool_t isOutside =
         (x < gPad->GetUxmin()) || (x > gPad->GetUxmax()) || (y < gPad->GetUymin()) || (y > gPad->GetUymax());
 
      if ((isOutside && !AnyOption0) || (!Draw0PointsX && theX[i] == 0.) || (!Draw0PointsY && theY[i] == 0.))
         continue;
 
      if (AnyOption3) {
         if (isOutside) {
            if (x < gPad->GetUxmin())
               x = gPad->GetUxmin();
            if (x > gPad->GetUxmax())
               x = gPad->GetUxmax();
            if (y < gPad->GetUymin())
               y = gPad->GetUymin();
            if (y > gPad->GetUymax())
               y = gPad->GetUymax();
         }
 
         xline[if1 - 1] = x;
         xline[if2 - 1] = x;
 
         if1++;
         if2--;
      }
 
      for (Int_t j = 0; j < NYErrors; j++) {
         if (!DrawErrors[j])
            continue;
 
         //  draw the error rectangles
         if (Option2[j] && (!isOutside || Option0[j])) {
            if (IndividualStyles) {
               box.SetLineWidth(tg->GetLineWidth(j));
               box.SetLineColor(tg->GetLineColor(j));
               box.SetFillColor(tg->GetFillColor(j));
               box.SetFillStyle(tg->GetFillStyle(j));
            }
 
            x1b = gPad->XtoPad(theX[i] - Scale[j] * theExL[i]);
            y1b = gPad->YtoPad(theY[i] - theEyL[j][i]);
            x2b = gPad->XtoPad(theX[i] + Scale[j] * theExH[i]);
            y2b = gPad->YtoPad(theY[i] + theEyH[j][i]);
            if (x1b < gPad->GetUxmin())
               x1b = gPad->GetUxmin();
            if (x1b > gPad->GetUxmax())
               x1b = gPad->GetUxmax();
            if (y1b < gPad->GetUymin())
               y1b = gPad->GetUymin();
            if (y1b > gPad->GetUymax())
               y1b = gPad->GetUymax();
            if (x2b < gPad->GetUxmin())
               x2b = gPad->GetUxmin();
            if (x2b > gPad->GetUxmax())
               x2b = gPad->GetUxmax();
            if (y2b < gPad->GetUymin())
               y2b = gPad->GetUymin();
            if (y2b > gPad->GetUymax())
               y2b = gPad->GetUymax();
            if (Option5[j])
               box.PaintBox(x1b, y1b, x2b, y2b, "l");
            else
               box.PaintBox(x1b, y1b, x2b, y2b);
         }
 
         //  keep points for fill area drawing
         if (Option3[j]) {
            if (!isOutside || Option0[j]) {
               yline[j][if1 - 2] = gPad->YtoPad(theY[i] + theEyH[j][i]);
               yline[j][if2] = gPad->YtoPad(theY[i] - theEyL[j][i]);
            } else {
               yline[j][if1 - 2] = gPad->GetUymin();
               yline[j][if2] = gPad->GetUymin();
            }
         }
 
         if (IndividualStyles) {
            tg->GetAttLine(j)->Modify();
 
            arrow.SetLineWidth(tg->GetLineWidth(j));
            arrow.SetLineColor(tg->GetLineColor(j));
            arrow.SetFillColor(tg->GetFillColor(j));
         }
 
         ylow1 = y - s2y * cy;
         ylow2 = gPad->YtoPad(theY[i] - theEyL[j][i]);
         if (ylow2 < gPad->GetUymin())
            ylow2 = gPad->GetUymin();
         if (ylow2 < ylow1 && DrawErrors[j] && !Option2[j] && !Option3[j] && (!isOutside || Option0[j])) {
            if (ArrowOpt[j])
               arrow.PaintArrow(x, ylow1, x, ylow2, asize, ArrowOpt[j]);
            else {
               if (!Brackets[j])
                  gPad->PaintLine(x, ylow1, x, ylow2);
               if (EndLines[j]) {
                  if (Braticks[j]) {
                     xb[0] = x - tx;
                     yb[0] = ylow2 + ty;
                     xb[1] = x - tx;
                     yb[1] = ylow2;
                     xb[2] = x + tx;
                     yb[2] = ylow2;
                     xb[3] = x + tx;
                     yb[3] = ylow2 + ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  } else
                     gPad->PaintLine(x - tx, ylow2, x + tx, ylow2);
               }
            }
         }
 
         yup1 = y + s2y * cy;
         yup2 = gPad->YtoPad(theY[i] + theEyH[j][i]);
         if (yup2 > gPad->GetUymax())
            yup2 = gPad->GetUymax();
         if (yup2 > yup1 && DrawErrors[j] && !Option2[j] && !Option3[j] && (!isOutside || Option0[j])) {
            if (ArrowOpt[j])
               arrow.PaintArrow(x, yup1, x, yup2, asize, ArrowOpt[j]);
            else {
               if (!Brackets[j])
                  gPad->PaintLine(x, yup1, x, yup2);
               if (EndLines[j]) {
                  if (Braticks[j]) {
                     xb[0] = x - tx;
                     yb[0] = yup2 - ty;
                     xb[1] = x - tx;
                     yb[1] = yup2;
                     xb[2] = x + tx;
                     yb[2] = yup2;
                     xb[3] = x + tx;
                     yb[3] = yup2 - ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  } else
                     gPad->PaintLine(x - tx, yup2, x + tx, yup2);
               }
            }
         }
      }
 
      if (DrawErrorsX) {
         if (IndividualStyles) {
            tg->TAttLine::Modify();
 
            arrow.SetLineWidth(tg->GetLineWidth());
            arrow.SetLineColor(tg->GetLineColor());
            arrow.SetFillColor(tg->GetFillColor());
         }
 
         xl1 = x - s2x * cx;
         xl2 = gPad->XtoPad(theX[i] - ScaleX * theExL[i]);
         if (xl1 > xl2 && !NoErrorsX && (!isOutside || Option0X)) {
            if (ArrowOptX)
               arrow.PaintArrow(xl1, y, xl2, y, asize, ArrowOptX);
            else {
               if (!BracketsX)
                  gPad->PaintLine(xl1, y, xl2, y);
               if (EndLinesX) {
                  if (BraticksX) {
                     xb[0] = xl2 + tx;
                     yb[0] = y - ty;
                     xb[1] = xl2;
                     yb[1] = y - ty;
                     xb[2] = xl2;
                     yb[2] = y + ty;
                     xb[3] = xl2 + tx;
                     yb[3] = y + ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  } else
                     gPad->PaintLine(xl2, y - ty, xl2, y + ty);
               }
            }
         }
 
         xr1 = x + s2x * cx;
         xr2 = gPad->XtoPad(theX[i] + ScaleX * theExH[i]);
         if (xr1 < xr2 && !NoErrorsX && (!isOutside || Option0X)) {
            if (ArrowOptX)
               arrow.PaintArrow(xr1, y, xr2, y, asize, ArrowOptX);
            else {
               if (!BracketsX)
                  gPad->PaintLine(xr1, y, xr2, y);
               if (EndLinesX) {
                  if (BraticksX) {
                     xb[0] = xr2 - tx;
                     yb[0] = y - ty;
                     xb[1] = xr2;
                     yb[1] = y - ty;
                     xb[2] = xr2;
                     yb[2] = y + ty;
                     xb[3] = xr2 - tx;
                     yb[3] = y + ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  } else
                     gPad->PaintLine(xr2, y - ty, xr2, y + ty);
               }
            }
         }
      }
   }
 
   if (DrawMarker && !DrawAxis)
      PaintGraphSimple(tg, options[0].Data());
   gPad->ResetBit(TGraph::kClipFrame);
 
   TGraph tgDummy;
   tg->TAttFill::Copy(tgDummy);
   tg->TAttLine::Copy(tgDummy);
   tg->TAttMarker::Copy(tgDummy);
 
   for (Int_t j = 0; j < NYErrors; j++)
      if (Option3[j] && DrawErrors[j]) {
         if (IndividualStyles) {
            tg->GetAttFill(j)->Copy(tgDummy);
            tg->GetAttLine(j)->Copy(tgDummy);
         }
 
         Int_t logx = gPad->GetLogx();
         Int_t logy = gPad->GetLogy();
         gPad->SetLogx(0);
         gPad->SetLogy(0);
         if (Option4[j])
            PaintGraph(&tgDummy, 2 * NPointsInside, xline.data(), yline[j].data(), "FC");
         else
            PaintGraph(&tgDummy, 2 * NPointsInside, xline.data(), yline[j].data(), "F");
         gPad->SetLogx(logx);
         gPad->SetLogy(logy);
      }
 
}
 
////////////////////////////////////////////////////////////////////////////////
/// [Paint this TGraphBentErrors with its current attributes.](\ref GrP3)
 
void TGraphPainter::PaintGraphBentErrors(TGraph *theGraph, Option_t *option)
{
 
   std::vector<Double_t> xline, yline;
   Int_t if1 = 0;
   Int_t if2 = 0;
   Double_t xb[4], yb[4];
 
   const Int_t kBASEMARKER=8;
   static Float_t cxx[30] = {1.0,1.0,0.5,0.5,1.0,1.0,0.5,0.6,1.0,0.5,0.5,1.0,0.5,0.6,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   static Float_t cyy[30] = {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.5,0.5,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   Int_t theNpoints = theGraph->GetN();
   Double_t *theX  = theGraph->GetX();
   Double_t *theY  = theGraph->GetY();
   Double_t *theEXlow   = theGraph->GetEXlow();   if (!theEXlow) return;
   Double_t *theEYlow   = theGraph->GetEYlow();   if (!theEYlow) return;
   Double_t *theEXhigh  = theGraph->GetEXhigh();  if (!theEXhigh) return;
   Double_t *theEYhigh  = theGraph->GetEYhigh();  if (!theEYhigh) return;
   Double_t *theEXlowd  = theGraph->GetEXlowd();  if (!theEXlowd) return;
   Double_t *theEXhighd = theGraph->GetEXhighd(); if (!theEXhighd) return;
   Double_t *theEYlowd  = theGraph->GetEYlowd();  if (!theEYlowd) return;
   Double_t *theEYhighd = theGraph->GetEYhighd(); if (!theEYhighd) return;
 
   if (strchr(option,'X') || strchr(option,'x')) {PaintGraphSimple(theGraph, option); return;}
   Bool_t brackets = kFALSE;
   Bool_t braticks = kFALSE;
   if (strstr(option,"||") || strstr(option,"[]")) {
      brackets = kTRUE;
      if (strstr(option,"[]")) braticks = kTRUE;
   }
   Bool_t endLines = kTRUE;
   if (strchr(option,'z')) endLines = kFALSE;
   if (strchr(option,'Z')) endLines = kFALSE;
   const char *arrowOpt = nullptr;
   if (strchr(option,'>'))  arrowOpt = ">";
   if (strstr(option,"|>")) arrowOpt = "|>";
 
   Bool_t axis = kFALSE;
   if (strchr(option,'a')) axis = kTRUE;
   if (strchr(option,'A')) axis = kTRUE;
   if (axis) PaintGraphSimple(theGraph,option);
 
   Bool_t option0 = kFALSE;
   Bool_t option2 = kFALSE;
   Bool_t option3 = kFALSE;
   Bool_t option4 = kFALSE;
   Bool_t option5 = kFALSE;
   if (strchr(option,'0')) option0 = kTRUE;
   if (strchr(option,'2')) option2 = kTRUE;
   if (strchr(option,'3')) option3 = kTRUE;
   if (strchr(option,'4')) {option3 = kTRUE; option4 = kTRUE;}
   if (strchr(option,'5')) {option2 = kTRUE; option5 = kTRUE;}
 
   // special flags in case of "reverse plot" and "log scale"
   Bool_t xrevlog = kFALSE;
   Bool_t yrevlog = kFALSE;
   if (strstr(option,"-N")) xrevlog = kTRUE; // along X
   if (strstr(option,"-M")) yrevlog = kTRUE; // along Y
 
   if (option3) {
      xline.resize(2*theNpoints);
      yline.resize(2*theNpoints);
      if (xline.empty() || yline.empty()) {
         Error("PaintGraphBentErrors", "too many points, out of memory");
         return;
      }
      if1 = 1;
      if2 = 2*theNpoints;
   }
 
   theGraph->TAttLine::Modify();
 
   TArrow arrow;
   arrow.SetLineWidth(theGraph->GetLineWidth());
   arrow.SetLineColor(theGraph->GetLineColor());
   arrow.SetFillColor(theGraph->GetFillColor());
 
   TBox box;
   Double_t x1b,y1b,x2b,y2b;
   box.SetLineWidth(theGraph->GetLineWidth());
   box.SetLineColor(theGraph->GetLineColor());
   box.SetFillColor(theGraph->GetFillColor());
   box.SetFillStyle(theGraph->GetFillStyle());
 
   Double_t symbolsize = theGraph->GetMarkerSize();
   Double_t sbase = symbolsize*kBASEMARKER;
   Int_t mark = TAttMarker::GetMarkerStyleBase(theGraph->GetMarkerStyle());
   Double_t cx = 0;
   Double_t cy = 0;
   if (mark >= 20 && mark <= 49) {
      cx = cxx[mark-20];
      cy = cyy[mark-20];
   }
 
   // define the offset of the error bars due to the symbol size
   Double_t s2x =  gPad->PixeltoX(Int_t(0.5*sbase)) - gPad->PixeltoX(0);
   Double_t s2y = -gPad->PixeltoY(Int_t(0.5*sbase)) + gPad->PixeltoY(0);
   Int_t dxend  = Int_t(gStyle->GetEndErrorSize());
   Double_t tx  =  gPad->PixeltoX(dxend) - gPad->PixeltoX(0);
   Double_t ty  = -gPad->PixeltoY(dxend) + gPad->PixeltoY(0);
   Float_t asize = 0.6*symbolsize*kBASEMARKER/gPad->GetWh();
 
   gPad->SetBit(TGraph::kClipFrame, theGraph->TestBit(TGraph::kClipFrame));
 
   // loop over all the graph points
   Double_t x, y, exl, exh, eyl, eyh, xl1, xl2, xr1, xr2, yup1, yup2, ylow1, ylow2;
   Double_t bxl, bxh, byl, byh, bs;
   for (Int_t i=0;i<theNpoints;i++) {
      x   = gPad->XtoPad(theX[i]);
      y   = gPad->YtoPad(theY[i]);
      bxl = gPad->YtoPad(theY[i]+theEXlowd[i]);
      bxh = gPad->YtoPad(theY[i]+theEXhighd[i]);
      byl = gPad->XtoPad(theX[i]+theEYlowd[i]);
      byh = gPad->XtoPad(theX[i]+theEYhighd[i]);
 
      if (!option0) {
         if (option3) {
            if (x < gPad->GetUxmin()) x = gPad->GetUxmin();
            if (x > gPad->GetUxmax()) x = gPad->GetUxmax();
            if (y < gPad->GetUymin()) y = gPad->GetUymin();
            if (y > gPad->GetUymax()) y = gPad->GetUymax();
         } else {
            if (x < gPad->GetUxmin()) continue;
            if (x > gPad->GetUxmax()) continue;
            if (y < gPad->GetUymin()) continue;
            if (y > gPad->GetUymax()) continue;
         }
      }
      exl = theEXlow[i];
      exh = theEXhigh[i];
      eyl = theEYlow[i];
      eyh = theEYhigh[i];
 
      if (xrevlog) {
         xl1 = x + s2x*cx;
         xl2 = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               - exh);
         xr1 = x - s2x*cx;
         xr2 = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               + exl);
         tx = -tx;
         byl = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               - theEYlowd[i]);
         byh = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               - theEYhighd[i]);
      } else {
         xl1 = x - s2x*cx;
         xl2 = gPad->XtoPad(theX[i] - exl);
         xr1 = x + s2x*cx;
         xr2 = gPad->XtoPad(theX[i] + exh);
      }
 
      if (yrevlog) {
         yup1 = y - s2y*cy;
         yup2 = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               + eyl);
         ylow1 = y + s2y*cy;
         ylow2 = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               - eyh);
         bxl = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               - theEXlowd[i]);
         bxh = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               - theEXhighd[i]);
      } else {
         yup1  = y + s2y*cy;
         yup2  = gPad->YtoPad(theY[i] + eyh);
         ylow1 = y - s2y*cy;
         ylow2 = gPad->YtoPad(theY[i] - eyl);
      }
      if (yup2 > gPad->GetUymax()) yup2 =  gPad->GetUymax();
      if (ylow2 < gPad->GetUymin()) ylow2 =  gPad->GetUymin();
 
      if (xrevlog) {bs = bxl; bxl = bxh; bxh = bs;}
      if (yrevlog) {bs = byl; byl = byh; byh = bs;}
 
      //  draw the error rectangles
      if (option2) {
         x1b = xl2;
         y1b = ylow2;
         x2b = xr2;
         y2b = yup2;
         if (x1b < gPad->GetUxmin()) x1b = gPad->GetUxmin();
         if (x1b > gPad->GetUxmax()) x1b = gPad->GetUxmax();
         if (y1b < gPad->GetUymin()) y1b = gPad->GetUymin();
         if (y1b > gPad->GetUymax()) y1b = gPad->GetUymax();
         if (x2b < gPad->GetUxmin()) x2b = gPad->GetUxmin();
         if (x2b > gPad->GetUxmax()) x2b = gPad->GetUxmax();
         if (y2b < gPad->GetUymin()) y2b = gPad->GetUymin();
         if (y2b > gPad->GetUymax()) y2b = gPad->GetUymax();
         if (option5) box.PaintBox(x1b, y1b, x2b, y2b, "l");
         else         box.PaintBox(x1b, y1b, x2b, y2b);
         continue;
      }
 
      //  keep points for fill area drawing
      if (option3) {
         xline[if1-1] = byh;
         xline[if2-1] = byl;
         yline[if1-1] = yup2;
         yline[if2-1] = ylow2;
         if1++;
         if2--;
         continue;
      }
 
      if (exl != 0. || exh != 0.) {
         if (arrowOpt) {
            if (exl != 0.) arrow.PaintArrow(xl1,y,xl2,bxl,asize,arrowOpt);
            if (exh != 0.) arrow.PaintArrow(xr1,y,xr2,bxh,asize,arrowOpt);
         } else {
            if (!brackets) {
               if (exl != 0.) gPad->PaintLine(xl1,y,xl2,bxl);
               if (exh != 0.) gPad->PaintLine(xr1,y,xr2,bxh);
            }
            if (endLines) {
               if (braticks) {
                  if (exl != 0.) {
                     xb[0] = xl2+tx; yb[0] = bxl-ty;
                     xb[1] = xl2;    yb[1] = bxl-ty;
                     xb[2] = xl2;    yb[2] = bxl+ty;
                     xb[3] = xl2+tx; yb[3] = bxl+ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
                  if (exh != 0.) {
                     xb[0] = xr2-tx; yb[0] = bxh-ty;
                     xb[1] = xr2;    yb[1] = bxh-ty;
                     xb[2] = xr2;    yb[2] = bxh+ty;
                     xb[3] = xr2-tx; yb[3] = bxh+ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
               } else {
                  gPad->PaintLine(xl2,bxl-ty,xl2,bxl+ty);
                  gPad->PaintLine(xr2,bxh-ty,xr2,bxh+ty);
               }
            }
         }
      }
 
      if (eyl != 0. || eyh != 0.) {
         if (arrowOpt) {
            if (eyh != 0.) arrow.PaintArrow(x,yup1,byh,yup2,asize,arrowOpt);
            if (eyl != 0.) arrow.PaintArrow(x,ylow1,byl,ylow2,asize,arrowOpt);
         } else {
            if (!brackets) {
               if (eyh != 0.) gPad->PaintLine(x,yup1,byh,yup2);
               if (eyl != 0.) gPad->PaintLine(x,ylow1,byl,ylow2);
            }
            if (endLines) {
               if (braticks) {
                  if (eyh != 0.) {
                     xb[0] = byh-tx; yb[0] = yup2-ty;
                     xb[1] = byh-tx; yb[1] = yup2;
                     xb[2] = byh+tx; yb[2] = yup2;
                     xb[3] = byh+tx; yb[3] = yup2-ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
                  if (eyl != 0.) {
                     xb[0] = byl-tx; yb[0] = ylow2+ty;
                     xb[1] = byl-tx; yb[1] = ylow2;
                     xb[2] = byl+tx; yb[2] = ylow2;
                     xb[3] = byl+tx; yb[3] = ylow2+ty;
                     gPad->PaintPolyLine(4, xb, yb);
                  }
               } else {
                  if (eyh != 0.) gPad->PaintLine(byh-tx,yup2,byh+tx,yup2);
                  if (eyl != 0.) gPad->PaintLine(byl-tx,ylow2,byl+tx,ylow2);
               }
            }
         }
      }
   }
 
   if (!brackets && !axis) PaintGraphSimple(theGraph, option);
   gPad->ResetBit(TGraph::kClipFrame);
 
   if (option3) {
      Int_t logx = gPad->GetLogx();
      Int_t logy = gPad->GetLogy();
      gPad->SetLogx(0);
      gPad->SetLogy(0);
      if (option4) PaintGraph(theGraph, 2*theNpoints, xline.data(), yline.data(),"FC");
      else         PaintGraph(theGraph, 2*theNpoints, xline.data(), yline.data(),"F");
      gPad->SetLogx(logx);
      gPad->SetLogy(logy);
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// [Paint this TGraphErrors with its current attributes.](\ref GrP3)
 
void TGraphPainter::PaintGraphErrors(TGraph *theGraph, Option_t *option)
{
 
   std::vector<Double_t> xline, yline;
   Int_t if1 = 0;
   Int_t if2 = 0;
   Double_t xb[4], yb[4];
 
   const Int_t kBASEMARKER=8;
   static Float_t cxx[30] = {1.0,1.0,0.5,0.5,1.0,1.0,0.5,0.6,1.0,0.5,0.5,1.0,0.5,0.6,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   static Float_t cyy[30] = {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.5,0.5,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,0.0,0.0,1.0,1.0,1.0,1.0,0.5,0.5,0.5,1.0};
   Int_t theNpoints = theGraph->GetN();
   Double_t *theX  = theGraph->GetX();
   Double_t *theY  = theGraph->GetY();
   Double_t *theEX = theGraph->GetEX(); if (!theEX) return;
   Double_t *theEY = theGraph->GetEY(); if (!theEY) return;
 
   if (strchr(option,'X') || strchr(option,'x')) {PaintGraphSimple(theGraph, option); return;}
   Bool_t brackets = kFALSE;
   Bool_t braticks = kFALSE;
   if (strstr(option,"||") || strstr(option,"[]")) {
      brackets = kTRUE;
      if (strstr(option,"[]")) braticks = kTRUE;
   }
   Bool_t endLines = kTRUE;
   if (strchr(option,'z')) endLines = kFALSE;
   if (strchr(option,'Z')) endLines = kFALSE;
   const char *arrowOpt = nullptr;
   if (strchr(option,'>'))  arrowOpt = ">";
   if (strstr(option,"|>")) arrowOpt = "|>";
 
   Bool_t axis = kFALSE;
   if (strchr(option,'a')) axis = kTRUE;
   if (strchr(option,'A')) axis = kTRUE;
   if (axis) PaintGraphSimple(theGraph, option);
 
   Bool_t option0 = kFALSE;
   Bool_t option2 = kFALSE;
   Bool_t option3 = kFALSE;
   Bool_t option4 = kFALSE;
   Bool_t option5 = kFALSE;
   if (strchr(option,'0')) option0 = kTRUE;
   if (strchr(option,'2')) option2 = kTRUE;
   if (strchr(option,'3')) option3 = kTRUE;
   if (strchr(option,'4')) {option3 = kTRUE; option4 = kTRUE;}
   if (strchr(option,'5')) {option2 = kTRUE; option5 = kTRUE;}
 
   // special flags in case of "reverse plot" and "log scale"
   Bool_t xrevlog = kFALSE;
   Bool_t yrevlog = kFALSE;
   if (strstr(option,"-N")) xrevlog = kTRUE; // along X
   if (strstr(option,"-M")) yrevlog = kTRUE; // along Y
 
   if (option3) {
      xline.resize(2*theNpoints);
      yline.resize(2*theNpoints);
      if (xline.empty() || yline.empty()) {
         Error("PaintGraphErrors", "too many points, out of memory");
         return;
      }
      if1 = 1;
      if2 = 2*theNpoints;
   }
 
   theGraph->TAttLine::Modify();
 
   TArrow arrow;
   arrow.SetLineWidth(theGraph->GetLineWidth());
   arrow.SetLineColor(theGraph->GetLineColor());
   arrow.SetFillColor(theGraph->GetFillColor());
 
   TBox box;
   Double_t x1b,y1b,x2b,y2b;
   box.SetLineWidth(theGraph->GetLineWidth());
   box.SetLineColor(theGraph->GetLineColor());
   box.SetFillColor(theGraph->GetFillColor());
   box.SetFillStyle(theGraph->GetFillStyle());
 
   Double_t symbolsize = theGraph->GetMarkerSize();
   Double_t sbase = symbolsize*kBASEMARKER;
   Int_t mark = TAttMarker::GetMarkerStyleBase(theGraph->GetMarkerStyle());
   Double_t cx = 0;
   Double_t cy = 0;
   if (mark >= 20 && mark <= 49) {
      cx = cxx[mark-20];
      cy = cyy[mark-20];
   }
 
   // define the offset of the error bars due to the symbol size
   Double_t s2x =  gPad->PixeltoX(Int_t(0.5*sbase)) - gPad->PixeltoX(0);
   Double_t s2y = -gPad->PixeltoY(Int_t(0.5*sbase)) + gPad->PixeltoY(0);
   Int_t dxend  = Int_t(gStyle->GetEndErrorSize());
   Double_t tx  =  gPad->PixeltoX(dxend) - gPad->PixeltoX(0);
   Double_t ty  = -gPad->PixeltoY(dxend) + gPad->PixeltoY(0);
   Float_t asize = 0.6*symbolsize*kBASEMARKER/gPad->GetWh();
 
   gPad->SetBit(TGraph::kClipFrame, theGraph->TestBit(TGraph::kClipFrame));
 
   // loop over all the graph points
   Double_t x, y, ex, ey, xl1, xl2, xr1, xr2, yup1, yup2, ylow1, ylow2;
   for (Int_t i=0;i<theNpoints;i++) {
      x  = gPad->XtoPad(theX[i]);
      y  = gPad->YtoPad(theY[i]);
 
      if (!option0) {
         if (option3) {
            if (x < gPad->GetUxmin()) x = gPad->GetUxmin();
            if (x > gPad->GetUxmax()) x = gPad->GetUxmax();
            if (y < gPad->GetUymin()) y = gPad->GetUymin();
            if (y > gPad->GetUymax()) y = gPad->GetUymax();
         } else {
            if (x < gPad->GetUxmin()) continue;
            if (x > gPad->GetUxmax()) continue;
            if (y < gPad->GetUymin()) continue;
            if (y > gPad->GetUymax()) continue;
         }
      }
      ex = theEX[i];
      ey = theEY[i];
 
      if (xrevlog) {
         xl1 = x + s2x*cx;
         xl2 = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               - ex);
         xr1 = x - s2x*cx;
         xr2 = gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theX[i])-gPad->GetUxmax()-gPad->GetUxmin()))
               + ex);
         tx = -tx;
      } else {
         xl1 = x - s2x*cx;
         xl2 = gPad->XtoPad(theX[i] - ex);
         xr1 = x + s2x*cx;
         xr2 = gPad->XtoPad(theX[i] + ex);
      }
 
      if (yrevlog) {
         yup1 = y - s2y*cy;
         yup2 = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               + ey);
         ylow1 = y + s2y*cy;
         ylow2 = gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(
               TMath::Power(10,-(TMath::Log10(theY[i])-gPad->GetUymax()-gPad->GetUymin()))
               - ey);
      } else {
         yup1 = y + s2y*cy;
         yup2 = gPad->YtoPad(theY[i] + ey);
         ylow1 = y - s2y*cy;
         ylow2 = gPad->YtoPad(theY[i] - ey);
      }
      if (yup2 > gPad->GetUymax()) yup2 =  gPad->GetUymax();
      if (ylow2 < gPad->GetUymin()) ylow2 =  gPad->GetUymin();
 
      //  draw the error rectangles
      if (option2) {
         x1b = xl2;
         x2b = xr2;
         y1b = ylow2;
         y2b = yup2;
         if (x1b < gPad->GetUxmin()) x1b = gPad->GetUxmin();
         if (x1b > gPad->GetUxmax()) x1b = gPad->GetUxmax();
         if (y1b < gPad->GetUymin()) y1b = gPad->GetUymin();
         if (y1b > gPad->GetUymax()) y1b = gPad->GetUymax();
         if (x2b < gPad->GetUxmin()) x2b = gPad->GetUxmin();
         if (x2b > gPad->GetUxmax()) x2b = gPad->GetUxmax();
         if (y2b < gPad->GetUymin()) y2b = gPad->GetUymin();
         if (y2b > gPad->GetUymax()) y2b = gPad->GetUymax();
         if (option5) box.PaintBox(x1b, y1b, x2b, y2b, "l");
         else         box.PaintBox(x1b, y1b, x2b, y2b);
         continue;
      }
 
      //  keep points for fill area drawing
      if (option3) {
         xline[if1-1] = x;
         xline[if2-1] = x;
         yline[if1-1] = yup2;
         yline[if2-1] = ylow2;
         if1++;
         if2--;
         continue;
      }
 
      if (ex != 0.) {
         if (arrowOpt) {
            arrow.PaintArrow(xl1,y,xl2,y,asize,arrowOpt);
            arrow.PaintArrow(xr1,y,xr2,y,asize,arrowOpt);
         } else {
            if (!brackets) {
               gPad->PaintLine(xl1,y,xl2,y);
               gPad->PaintLine(xr1,y,xr2,y);
            }
            if (endLines) {
               if (braticks) {
                  xb[0] = xl2+tx; yb[0] = y-ty;
                  xb[1] = xl2;    yb[1] = y-ty;
                  xb[2] = xl2;    yb[2] = y+ty;
                  xb[3] = xl2+tx; yb[3] = y+ty;
                  gPad->PaintPolyLine(4, xb, yb);
                  xb[0] = xr2-tx; yb[0] = y-ty;
                  xb[1] = xr2;    yb[1] = y-ty;
                  xb[2] = xr2;    yb[2] = y+ty;
                  xb[3] = xr2-tx; yb[3] = y+ty;
                  gPad->PaintPolyLine(4, xb, yb);
               } else {
                  gPad->PaintLine(xl2,y-ty,xl2,y+ty);
                  gPad->PaintLine(xr2,y-ty,xr2,y+ty);
               }
            }
         }
      }
 
      if (ey != 0.) {
         if (arrowOpt) {
            arrow.PaintArrow(x,yup1,x,yup2,asize,arrowOpt);
            arrow.PaintArrow(x,ylow1,x,ylow2,asize,arrowOpt);
         } else {
            if (!brackets) {
               gPad->PaintLine(x,yup1,x,yup2);
               gPad->PaintLine(x,ylow1,x,ylow2);
            }
            if (endLines) {
               if (braticks) {
                  xb[0] = x-tx; yb[0] = yup2-ty;
                  xb[1] = x-tx; yb[1] = yup2;
                  xb[2] = x+tx; yb[2] = yup2;
                  xb[3] = x+tx; yb[3] = yup2-ty;
                  gPad->PaintPolyLine(4, xb, yb);
                  xb[0] = x-tx; yb[0] = ylow2+ty;
                  xb[1] = x-tx; yb[1] = ylow2;
                  xb[2] = x+tx; yb[2] = ylow2;
                  xb[3] = x+tx; yb[3] = ylow2+ty;
                  gPad->PaintPolyLine(4, xb, yb);
                } else {
                  gPad->PaintLine(x-tx,yup2,x+tx,yup2);
                  gPad->PaintLine(x-tx,ylow2,x+tx,ylow2);
               }
            }
         }
      }
   }
 
   if (!brackets && !axis) PaintGraphSimple(theGraph, option);
   gPad->ResetBit(TGraph::kClipFrame);
 
   if (option3) {
      Int_t logx = gPad->GetLogx();
      Int_t logy = gPad->GetLogy();
      gPad->SetLogx(0);
      gPad->SetLogy(0);
      if (option4) PaintGraph(theGraph, 2*theNpoints, xline.data(), yline.data(),"FC");
      else         PaintGraph(theGraph, 2*theNpoints, xline.data(), yline.data(),"F");
      gPad->SetLogx(logx);
      gPad->SetLogy(logy);
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// [Paint this TGraphPolar with its current attributes.](\ref GrP4)
 
void TGraphPainter::PaintGraphPolar(TGraph *theGraph, Option_t* options)
{
 
   Int_t ipt, i;
   Double_t rwrmin, rwrmax, rwtmin, rwtmax;
 
   TGraphPolar *theGraphPolar = (TGraphPolar*) theGraph;
 
   Int_t theNpoints  = theGraphPolar->GetN();
   Double_t *theX    = theGraphPolar->GetX();
   Double_t *theY    = theGraphPolar->GetY();
   Double_t *theEX   = theGraphPolar->GetEX();
   Double_t *theEY   = theGraphPolar->GetEY();
 
   if (theNpoints<1) return;
   TString opt = options;
   opt.ToUpper();
 
   Bool_t nolabel = kFALSE;
   if (opt.Contains("N")){
      nolabel = kTRUE;
      opt.ReplaceAll("N","");
   }
 
   TGraphPolargram *thePolargram = theGraphPolar->GetPolargram();
 
   // Check for existing TGraphPolargram in the Pad
   if (gPad) {
      // Existing polargram
      if (thePolargram) if (!gPad->FindObject(thePolargram->GetName())) thePolargram=nullptr;
      if (!thePolargram) {
         // Find any other Polargram in the Pad
         TListIter padObjIter(gPad->GetListOfPrimitives());
         while (TObject* AnyObj = padObjIter.Next()) {
            if (TString(AnyObj->ClassName()).CompareTo("TGraphPolargram",
                                                      TString::kExact)==0)
            thePolargram = (TGraphPolargram*)AnyObj;
            theGraphPolar->SetPolargram(thePolargram);
         }
      }
   }
 
   // Get new polargram range if necessary.
   if (!thePolargram) {
      // Get range, initialize with first/last value
      rwrmin = theY[0]; rwrmax = theY[theNpoints-1];
      rwtmin = theX[0]; rwtmax = theX[theNpoints-1];
 
      for (ipt = 0; ipt < theNpoints; ipt++) {
         // Check for errors if available
         if (theEX) {
            if (theX[ipt] -theEX[ipt] < rwtmin) rwtmin = theX[ipt]-theEX[ipt];
            if (theX[ipt] +theEX[ipt] > rwtmax) rwtmax = theX[ipt]+theEX[ipt];
         } else {
            if (theX[ipt] < rwtmin) rwtmin=theX[ipt];
            if (theX[ipt] > rwtmax) rwtmax=theX[ipt];
         }
         if (theEY) {
            if (theY[ipt] -theEY[ipt] < rwrmin) rwrmin = theY[ipt]-theEY[ipt];
            if (theY[ipt] +theEY[ipt] > rwrmax) rwrmax = theY[ipt]+theEY[ipt];
         } else {
            if (theY[ipt] < rwrmin) rwrmin=theY[ipt];
            if (theY[ipt] > rwrmax) rwrmax=theY[ipt];
         }
      }
      // Add radial and Polar margins.
      if (rwrmin == rwrmax) rwrmax += 1.;
      if (rwtmin == rwtmax) rwtmax += 1.;
      Double_t dr = (rwrmax-rwrmin);
      Double_t dt = (rwtmax-rwtmin);
      rwrmax += 0.1*dr;
      rwrmin -= 0.1*dr;
 
      // Assume equally spaced points for full 2*Pi.
      rwtmax += dt/theNpoints;
   } else {
      rwrmin = thePolargram->GetRMin();
      rwrmax = thePolargram->GetRMax();
      rwtmin = thePolargram->GetTMin();
      rwtmax = thePolargram->GetTMax();
   }
 
   if ((!thePolargram) || theGraphPolar->GetOptionAxis()) {
      // Draw Polar coord system
      thePolargram = new TGraphPolargram("Polargram",rwrmin,rwrmax,rwtmin,rwtmax);
      theGraphPolar->SetPolargram(thePolargram);
      if (opt.Contains("O")) thePolargram->SetBit(TGraphPolargram::kLabelOrtho);
      else thePolargram->ResetBit(TGraphPolargram::kLabelOrtho);
      if (nolabel) thePolargram->Draw("N");
      else         thePolargram->Draw("");
      theGraphPolar->SetOptionAxis(kFALSE);   //Prevent redrawing
   }
 
   // Convert points to polar.
   Double_t *theXpol = theGraphPolar->GetXpol();
   Double_t *theYpol = theGraphPolar->GetYpol();
 
   // Project theta in [0,2*Pi] and radius in [0,1].
   Double_t radiusNDC = rwrmax-rwrmin;
   Double_t thetaNDC  = (rwtmax-rwtmin)/(2*TMath::Pi());
 
   // Draw the error bars.
   // Y errors are lines, but X errors are pieces of circles.
   if (opt.Contains("E")) {
      Double_t c=1;
      if (thePolargram->IsDegree()) {c=180/TMath::Pi();}
      if (thePolargram->IsGrad())   {c=100/TMath::Pi();}
      if (theEY) {
         for (i=0; i<theNpoints; i++) {
            Double_t eymin, eymax, exmin,exmax;
            exmin = (theY[i]-theEY[i]-rwrmin)/radiusNDC*
                     TMath::Cos(c*(theX[i]-rwtmin)/thetaNDC);
            eymin = (theY[i]-theEY[i]-rwrmin)/radiusNDC*
                     TMath::Sin(c*(theX[i]-rwtmin)/thetaNDC);
            exmax = (theY[i]+theEY[i]-rwrmin)/radiusNDC*
                     TMath::Cos(c*(theX[i]-rwtmin)/thetaNDC);
            eymax = (theY[i]+theEY[i]-rwrmin)/radiusNDC*
                     TMath::Sin(c*(theX[i]-rwtmin)/thetaNDC);
            theGraphPolar->TAttLine::Modify();
            if (exmin != exmax || eymin != eymax) gPad->PaintLine(exmin,eymin,exmax,eymax);
         }
      }
      if (theEX) {
         for (i=0; i<theNpoints; i++) {
            Double_t rad    = (theY[i]-rwrmin)/radiusNDC;
            Double_t phimin = c*(theX[i]-theEX[i]-rwtmin)/thetaNDC*180/TMath::Pi();
            Double_t phimax = c*(theX[i]+theEX[i]-rwtmin)/thetaNDC*180/TMath::Pi();
            theGraphPolar->TAttLine::Modify();
            if (phimin != phimax) thePolargram->PaintCircle(0,0,rad,phimin,phimax,0);
         }
      }
   }
 
   // Draw the graph itself.
   if (!(gPad->GetLogx()) && !(gPad->GetLogy())) {
      Double_t a, b, c=1, x1, x2, y1, y2, discr, norm1, norm2, xts, yts;
      Bool_t previouspointin = kFALSE;
      Double_t norm = 0;
      Double_t xt   = 0;
      Double_t yt   = 0 ;
      Int_t j       = -1;
      if (thePolargram->IsDegree()) {c=180/TMath::Pi();}
      if (thePolargram->IsGrad())   {c=100/TMath::Pi();}
      for (i=0; i<theNpoints; i++) {
         xts  = xt;
         yts  = yt;
         xt   = (theY[i]-rwrmin)/radiusNDC*TMath::Cos(c*(theX[i]-rwtmin)/thetaNDC);
         yt   = (theY[i]-rwrmin)/radiusNDC*TMath::Sin(c*(theX[i]-rwtmin)/thetaNDC);
         norm = sqrt(xt*xt+yt*yt);
         // Check if points are in the main circle.
         if ( norm <= 1) {
            // We check that the previous point was in the circle too.
            // We record new point position.
            if (!previouspointin) {
               j++;
               theXpol[j] = xt;
               theYpol[j] = yt;
            } else {
               a = (yt-yts)/(xt-xts);
               b = yts-a*xts;
               discr = 4*(a*a-b*b+1);
               x1 = (-2*a*b+sqrt(discr))/(2*(a*a+1));
               x2 = (-2*a*b-sqrt(discr))/(2*(a*a+1));
               y1 = a*x1+b;
               y2 = a*x2+b;
               norm1 = sqrt((x1-xt)*(x1-xt)+(y1-yt)*(y1-yt));
               norm2 = sqrt((x2-xt)*(x2-xt)+(y2-yt)*(y2-yt));
               previouspointin = kFALSE;
               j = 0;
               if (norm1 < norm2) {
                  theXpol[j] = x1;
                  theYpol[j] = y1;
               } else {
                  theXpol[j] = x2;
                  theYpol[j] = y2;
               }
               j++;
               theXpol[j] = xt;
               theYpol[j] = yt;
               PaintGraph(theGraphPolar, j+1, theXpol, theYpol, opt);
            }
         } else {
            // We check that the previous point was in the circle.
            // We record new point position
            if (j>=1 && !previouspointin) {
               a = (yt-theYpol[j])/(xt-theXpol[j]);
               b = theYpol[j]-a*theXpol[j];
               previouspointin = kTRUE;
               discr = 4*(a*a-b*b+1);
               x1 = (-2*a*b+sqrt(discr))/(2*(a*a+1));
               x2 = (-2*a*b-sqrt(discr))/(2*(a*a+1));
               y1 = a*x1+b;
               y2 = a*x2+b;
               norm1 = sqrt((x1-xt)*(x1-xt)+(y1-yt)*(y1-yt));
               norm2 = sqrt((x2-xt)*(x2-xt)+(y2-yt)*(y2-yt));
               j++;
               if (norm1 < norm2) {
                  theXpol[j] = x1;
                  theYpol[j] = y1;
               } else {
                  theXpol[j] = x2;
                  theYpol[j] = y2;
               }
               PaintGraph(theGraphPolar, j+1, theXpol, theYpol, opt);
            }
            j=-1;
         }
      }
      if (j>=1) {
         // If the last point is in the circle, we draw the last serie of point.
         PaintGraph(theGraphPolar, j+1, theXpol, theYpol, opt);
      }
   } else {
      for (i=0; i<theNpoints; i++) {
         theXpol[i] = TMath::Abs((theY[i]-rwrmin)/radiusNDC*TMath::Cos((theX[i]-rwtmin)/thetaNDC)+1);
         theYpol[i] = TMath::Abs((theY[i]-rwrmin)/radiusNDC*TMath::Sin((theX[i]-rwtmin)/thetaNDC)+1);
      }
      PaintGraph(theGraphPolar, theNpoints, theXpol, theYpol,opt);
   }
 
   // Paint the title.
 
   if (TestBit(TH1::kNoTitle)) return;
   Int_t nt = strlen(theGraph->GetTitle());
   TPaveText *title = nullptr;
   TIter next(gPad->GetListOfPrimitives());
   while (auto obj = next()) {
      if (!obj->InheritsFrom(TPaveText::Class())) continue;
      title = (TPaveText*)obj;
      if (title->GetName())
         if (strcmp(title->GetName(),"title")) {title = nullptr; continue;}
      break;
   }
   if (nt == 0 || gStyle->GetOptTitle() <= 0) {
      if (title) delete title;
      return;
   }
   Double_t ht = gStyle->GetTitleH();
   Double_t wt = gStyle->GetTitleW();
   if (ht <= 0) ht = 1.1*gStyle->GetTitleFontSize();
   if (ht <= 0) ht = 0.05;
   if (wt <= 0) {
      TLatex l;
      l.SetTextSize(ht);
      l.SetTitle(theGraph->GetTitle());
      // Adjustment in case the title has several lines (#splitline)
      ht = TMath::Max(ht, 1.2*l.GetYsize()/(gPad->GetY2() - gPad->GetY1()));
      Double_t wndc = l.GetXsize()/(gPad->GetX2() - gPad->GetX1());
      wt = TMath::Min(0.7, 0.02+wndc);
   }
   if (title) {
      TText *t0 = (TText*)title->GetLine(0);
      if (t0) {
         if (!strcmp(t0->GetTitle(),theGraph->GetTitle())) return;
         t0->SetTitle(theGraph->GetTitle());
         if (wt > 0) title->SetX2NDC(title->GetX1NDC()+wt);
      }
      return;
   }
 
   Int_t talh = gStyle->GetTitleAlign()/10;
   if (talh < 1) talh = 1; else if (talh > 3) talh = 3;
   Int_t talv = gStyle->GetTitleAlign()%10;
   if (talv < 1) talv = 1; else if (talv > 3) talv = 3;
 
   Double_t xpos, ypos;
   xpos = gStyle->GetTitleX();
   ypos = gStyle->GetTitleY();
 
   if (talh == 2) xpos = xpos-wt/2.;
   if (talh == 3) xpos = xpos-wt;
   if (talv == 2) ypos = ypos+ht/2.;
   if (talv == 1) ypos = ypos+ht;
 
   TPaveText *ptitle = new TPaveText(xpos, ypos-ht, xpos+wt, ypos,"blNDC");
 
   // Box with the histogram title.
   ptitle->SetFillColor(gStyle->GetTitleFillColor());
   ptitle->SetFillStyle(gStyle->GetTitleStyle());
   ptitle->SetName("title");
   ptitle->SetBorderSize(gStyle->GetTitleBorderSize());
   ptitle->SetTextColor(gStyle->GetTitleTextColor());
   ptitle->SetTextFont(gStyle->GetTitleFont(""));
   if (gStyle->GetTitleFont("")%10 > 2)
   ptitle->SetTextSize(gStyle->GetTitleFontSize());
   ptitle->AddText(theGraph->GetTitle());
   ptitle->SetBit(kCanDelete);
   ptitle->Draw();
   ptitle->Paint();
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint this graphQQ. No options for the time being.
 
void TGraphPainter::PaintGraphQQ(TGraph *theGraph, Option_t *option)
{
 
   TGraphQQ *theGraphQQ = (TGraphQQ*) theGraph;
 
   Double_t *theX    = theGraphQQ->GetX();
   Double_t  theXq1  = theGraphQQ->GetXq1();
   Double_t  theXq2  = theGraphQQ->GetXq2();
   Double_t  theYq1  = theGraphQQ->GetYq1();
   Double_t  theYq2  = theGraphQQ->GetYq2();
   TF1      *theF    = theGraphQQ->GetF();
 
   if (!theX){
      Error("TGraphQQ::Paint", "2nd dataset or theoretical function not specified");
      return;
   }
 
   if (theF){
      theGraphQQ->GetXaxis()->SetTitle("theoretical quantiles");
      theGraphQQ->GetYaxis()->SetTitle("data quantiles");
   }
 
   PaintGraphSimple(theGraph,option);
 
   Double_t xmin = gPad->GetUxmin();
   Double_t xmax = gPad->GetUxmax();
   Double_t ymin = gPad->GetUymin();
   Double_t ymax = gPad->GetUymax();
   Double_t yxmin, xymin, yxmax, xymax;
   Double_t xqmin = TMath::Max(xmin, theXq1);
   Double_t xqmax = TMath::Min(xmax, theXq2);
   Double_t yqmin = TMath::Max(ymin, theYq1);
   Double_t yqmax = TMath::Min(ymax, theYq2);
 
   TLine line1, line2, line3;
   line1.SetLineStyle(2);
   line3.SetLineStyle(2);
   yxmin = (theYq2-theYq1)*(xmin-theXq1)/(theXq2-theXq1) + theYq1;
   if (yxmin < ymin){
      xymin = (theXq2-theXq1)*(ymin-theYq1)/(theYq2-theYq1) + theXq1;
      line1.PaintLine(xymin, ymin, xqmin, yqmin);
   }
   else
      line1.PaintLine(xmin, yxmin, xqmin, yqmin);
 
   line2.PaintLine(xqmin, yqmin, xqmax, yqmax);
 
   yxmax = (theYq2-theYq1)*(xmax-theXq1)/(theXq2-theXq1) + theYq1;
   if (yxmax > ymax){
      xymax = (theXq2-theXq1)*(ymax-theYq1)/(theYq2-theYq1) + theXq1;
      line3.PaintLine(xqmax, yqmax, xymax, ymax);
   }
   else
      line3.PaintLine(xqmax, yqmax, xmax, yxmax);
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint theGraph reverting values along X and/or Y axis. a new graph is created.
 
void TGraphPainter::PaintGraphReverse(TGraph *theGraph, Option_t *option)
{
   TString opt = option;
   opt.ToLower();
   TH1F *theHist = (TH1F *)theGraph->GetHistogram();
 
   Bool_t lrx = opt.Contains("rx");
   Bool_t lry = opt.Contains("ry");
   Bool_t lxp = opt.Contains("x+");
   Bool_t lyp = opt.Contains("y+");
   Bool_t axis = opt.Contains("a");
   opt.ReplaceAll("a", "");
 
   Double_t LOX = theHist->GetXaxis()->GetLabelOffset();
   Double_t TLX = theHist->GetXaxis()->GetTickLength();
   Double_t LOY = theHist->GetYaxis()->GetLabelOffset();
   Double_t TLY = theHist->GetYaxis()->GetTickLength();
   Int_t XACOL  = theHist->GetXaxis()->GetAxisColor();
   Int_t YACOL  = theHist->GetYaxis()->GetAxisColor();
 
   if (axis) {
      if (lrx) {
         theHist->GetXaxis()->SetTickLength(0.);
         theHist->GetXaxis()->SetLabelOffset(999.);
         theHist->GetXaxis()->SetAxisColor(gPad->GetFrameFillColor());
      }
      if (lry) {
         theHist->GetYaxis()->SetTickLength(0.);
         theHist->GetYaxis()->SetLabelOffset(999.);
         theHist->GetYaxis()->SetAxisColor(gPad->GetFrameFillColor());
      }
      TString opth = "0";
      if (lxp) opth.Append("x+");
      if (lyp) opth.Append("y+");
      theHist->Paint(opth.Data());
   }
 
   Int_t     N = theGraph->GetN();
 
   Double_t *X       = theGraph->GetX();
   Double_t *EXhigh  = theGraph->GetEXhigh();
   Double_t *EXhighd = theGraph->GetEXhighd();
   Double_t *EXlow   = theGraph->GetEXlow();
   Double_t *EXlowd  = theGraph->GetEXlowd();
 
   Double_t *Y       = theGraph->GetY();
   Double_t *EYhigh  = theGraph->GetEYhigh();
   Double_t *EYhighd = theGraph->GetEYhighd();
   Double_t *EYlow   = theGraph->GetEYlow();
   Double_t *EYlowd  = theGraph->GetEYlowd();
 
   Double_t XA1, XA2, YA1, YA2;
   if (axis) {
      XA1 = theGraph->GetXaxis()->GetXmin();
      XA2 = theGraph->GetXaxis()->GetXmax();
      YA1 = theGraph->GetYaxis()->GetXmin();
      YA2 = theGraph->GetYaxis()->GetXmax();
   } else {
      XA1 = gPad->GetUxmin();
      XA2 = gPad->GetUxmax();
      YA1 = gPad->GetUymin();
      YA2 = gPad->GetUymax();
   }
   Double_t dX  = XA1+XA2;
   Double_t dY  = YA1+YA2;
 
   // Create the new reversed graph
   TGraph *theReversedGraph   = (TGraph*)theGraph->Clone();
 
   Double_t *rX       = theReversedGraph->GetX();
   Double_t *rEXhigh  = theReversedGraph->GetEXhigh();
   Double_t *rEXhighd = theReversedGraph->GetEXhighd();
   Double_t *rEXlow   = theReversedGraph->GetEXlow();
   Double_t *rEXlowd  = theReversedGraph->GetEXlowd();
 
   Double_t *rY       = theReversedGraph->GetY();
   Double_t *rEYhigh  = theReversedGraph->GetEYhigh();
   Double_t *rEYhighd = theReversedGraph->GetEYhighd();
   Double_t *rEYlow   = theReversedGraph->GetEYlow();
   Double_t *rEYlowd  = theReversedGraph->GetEYlowd();
 
   theReversedGraph->SetMarkerStyle(theGraph->GetMarkerStyle());
   theReversedGraph->SetMarkerColor(theGraph->GetMarkerColor());
   theReversedGraph->SetLineStyle(theGraph->GetLineStyle());
   theReversedGraph->SetLineColor(theGraph->GetLineColor());
 
   Int_t i; // loop index
 
   // Reserve the TGraph along the X axis
   if (lrx) {
      opt.ReplaceAll("rx", "");
      if (axis) {
         // Reverse the X axis
         Double_t GL = 0.;
         theHist->GetXaxis()->SetTickLength(0.);
         theHist->GetXaxis()->SetLabelOffset(999.);
         gPad->Update();
         TString optax = "-SDH";
         if (gPad->GetGridx()) {
            if (gPad->GetLogy()) {
               GL = (TMath::Log10(YA2) - TMath::Log10(YA1)) / (gPad->GetY2() - gPad->GetY1());
            } else  {
               GL = (YA2 - YA1) / (gPad->GetY2() - gPad->GetY1());
            }
            optax.Append("W");
         }
         Double_t ypos;
         if (lxp) ypos = gPad->GetUymax();
         else     ypos = gPad->GetUymin();
         if (gPad->GetLogy()) ypos = TMath::Power(10,ypos);
         TGaxis *theReversedXaxis;
         if (gPad->GetLogx()) {
            optax.Append("G");
            theReversedXaxis = new TGaxis(TMath::Power(10,gPad->GetUxmax()),
                                    ypos,
                                    TMath::Power(10,gPad->GetUxmin()),
                                    ypos,
                                    theGraph->GetXaxis()->GetXmin(),
                                    theGraph->GetXaxis()->GetXmax(),
                                    theHist->GetNdivisions("X"),
                                    optax.Data(), -GL);
            if (theHist->GetXaxis()->GetMoreLogLabels()) theReversedXaxis->SetMoreLogLabels();
            theReversedXaxis->SetLabelOffset(LOX + theGraph->GetXaxis()->GetLabelSize());
         } else {
            theReversedXaxis = new TGaxis(gPad->GetUxmax(),
                                    ypos,
                                    gPad->GetUxmin(),
                                    ypos,
                                    theGraph->GetXaxis()->GetXmin(),
                                    theGraph->GetXaxis()->GetXmax(),
                                    theHist->GetNdivisions("X"),
                                    optax.Data(), -GL);
            theReversedXaxis->SetLabelOffset(LOX - theGraph->GetXaxis()->GetLabelSize());
         }
         theReversedXaxis->SetLabelFont(theGraph->GetXaxis()->GetLabelFont());
         theReversedXaxis->SetLabelSize(theGraph->GetXaxis()->GetLabelSize());
         theReversedXaxis->SetLabelColor(theGraph->GetXaxis()->GetLabelColor());
         theReversedXaxis->SetTickLength(TLX);
         theReversedXaxis->Paint();
      }
 
      // Reverse X coordinates
      if (gPad->GetLogx()) {
         for (i=0; i<N; i++) rX[i] = TMath::Power(10,gPad->GetUxmax()+gPad->GetUxmin()-TMath::Log10(X[i]));
         opt.Append("-N");
      } else {
         for (i=0; i<N; i++) rX[i] = dX-X[i];
      }
 
      // Reverse X asymmetric errors
      if (rEXhigh && EXlow) for (i=0; i<N; i++) rEXhigh[i] = EXlow[i];
      if (rEXlow && EXhigh) for (i=0; i<N; i++) rEXlow[i]  = EXhigh[i];
 
      // Reverse X bent parameters
      if (rEXhighd && EXlowd) for (i=0; i<N; i++) rEXhighd[i] = EXlowd[i];
      if (rEXlowd && EXhighd) for (i=0; i<N; i++) rEXlowd[i]  = EXhighd[i];
   }
 
   // Reserve the TGraph along the Y axis
   if (lry) {
      opt.ReplaceAll("ry", "");
      if (axis) {
         // Reverse the Y axis
         Double_t GL = 0.;
         gPad->Update();
         TString optax = "-SDH";
         if (gPad->GetGridy()) {
            if (gPad->GetLogx()) {
               GL = (TMath::Log10(XA2) - TMath::Log10(XA1)) / (gPad->GetX2() - gPad->GetX1());
            } else  {
               GL = (XA2 - XA1) / (gPad->GetX2() - gPad->GetX1());
            }
            optax.Append("W");
         }
         Double_t xpos;
         if (lyp) xpos = gPad->GetUxmax();
         else     xpos = gPad->GetUxmin();
         if (gPad->GetLogx()) xpos = TMath::Power(10,xpos);
         TGaxis *theReversedYaxis;
         if (gPad->GetLogy()) {
            optax.Append("G");
            theReversedYaxis = new TGaxis(xpos,
                                    TMath::Power(10,gPad->GetUymax()),
                                    xpos,
                                    TMath::Power(10,gPad->GetUymin()),
                                    theGraph->GetYaxis()->GetXmin(),
                                    theGraph->GetYaxis()->GetXmax(),
                                    theHist->GetNdivisions("Y"),
                                    optax.Data(), GL);
            if (theHist->GetYaxis()->GetMoreLogLabels()) theReversedYaxis->SetMoreLogLabels();
         } else {
            theReversedYaxis = new TGaxis(xpos,
                                    gPad->GetUymax(),
                                    xpos,
                                    gPad->GetUymin(),
                                    theGraph->GetYaxis()->GetXmin(),
                                    theGraph->GetYaxis()->GetXmax(),
                                    theHist->GetNdivisions("Y"),
                                    optax.Data(), GL);
         }
         theReversedYaxis->SetLabelFont(theGraph->GetYaxis()->GetLabelFont());
         theReversedYaxis->SetLabelSize(theGraph->GetYaxis()->GetLabelSize());
         theReversedYaxis->SetLabelColor(theGraph->GetYaxis()->GetLabelColor());
         theReversedYaxis->SetTickLength(-TLY);
         theReversedYaxis->SetLabelOffset(LOY-TLY);
         theReversedYaxis->Paint();
      }
 
      // Reverse Y coordinates
      if (gPad->GetLogy()) {
         for (i=0; i<N; i++) rY[i] = TMath::Power(10,gPad->GetUymax()+gPad->GetUymin()-TMath::Log10(Y[i]));
         opt.Append("-M");
      } else {
         for (i=0; i<N; i++) rY[i] = dY-Y[i];
      }
 
      // Reverse Y asymmetric errors
      if (rEYhigh && EYlow) for (i=0; i<N; i++) rEYhigh[i] = EYlow[i];
      if (rEYlow && EYhigh) for (i=0; i<N; i++) rEYlow[i]  = EYhigh[i];
 
      // Reverse Y bent parameters
      if (rEYhighd && EYlowd) for (i=0; i<N; i++) rEYhighd[i] = EYlowd[i];
      if (rEYlowd && EYhighd) for (i=0; i<N; i++) rEYlowd[i]  = EYhighd[i];
   }
 
   if (lrx) {
      if (rEYlowd)  for (i=0; i<N; i++) rEYlowd[i]  = -rEYlowd[i];
      if (rEYhighd) for (i=0; i<N; i++) rEYhighd[i] = -rEYhighd[i];
   }
   if (lry) {
      if (rEXlowd)  for (i=0; i<N; i++) rEXlowd[i]  = -rEXlowd[i];
      if (rEXhighd) for (i=0; i<N; i++) rEXhighd[i] = -rEXhighd[i];
   }
 
   PaintHelper(theReversedGraph,opt.Data());
 
   theHist->GetXaxis()->SetLabelOffset(LOX);
   theHist->GetXaxis()->SetTickLength(TLX);
   theHist->GetYaxis()->SetLabelOffset(LOY);
   theHist->GetYaxis()->SetTickLength(TLY);
   theHist->GetXaxis()->SetAxisColor(XACOL);
   theHist->GetYaxis()->SetAxisColor(YACOL);
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint a scatter plot
 
void TGraphPainter::PaintScatter(TScatter *theScatter, Option_t* chopt)
{
 
   Int_t optionAxis;
 
   TString opt = chopt;
   opt.ToUpper();
 
   if (opt.Contains("A")) optionAxis  = 1;  else optionAxis  = 0;
 
   double *theX         = theScatter->GetGraph()->GetX();
   double *theY         = theScatter->GetGraph()->GetY();
   int n                = theScatter->GetGraph()->GetN();
   double *theColor     = theScatter->GetColor();
   double *theSize      = theScatter->GetSize();
   double MinMarkerSize = theScatter->GetMinMarkerSize();
   double MaxMarkerSize = theScatter->GetMaxMarkerSize();
 
   double minx =  DBL_MAX;
   double maxx = -DBL_MAX;
   double miny =  DBL_MAX;
   double maxy = -DBL_MAX;
   double minc =  DBL_MAX;
   double maxc = -DBL_MAX;
   double mins =  DBL_MAX;
   double maxs = -DBL_MAX;
   for (int i=0; i<n; i++) {
      minx = TMath::Min(minx,theX[i]);
      maxx = TMath::Max(maxx,theX[i]);
      miny = TMath::Min(miny,theY[i]);
      maxy = TMath::Max(maxy,theY[i]);
      if (theColor) {
         minc = TMath::Min(minc,theColor[i]);
         maxc = TMath::Max(maxc,theColor[i]);
      }
      if (theSize) {
         mins = TMath::Min(mins,theSize[i]);
         maxs = TMath::Max(maxs,theSize[i]);
      }
   }
 
   // Make sure minimum and maximum values are different
   Double_t d, e = 0.1;
   if (minx == maxx) {
      if (theX[0] == 0.) {
         minx = -e;
         maxx = e;
      } else {
         d = TMath::Abs(theX[0]*e);
         minx = theX[0] - d;
         maxx = theX[0] + d;
      }
   }
   if (miny == maxy) {
      if (theY[0] == 0.) {
         miny = -e;
         maxy = e;
      } else {
         d = TMath::Abs(theY[0]*e);
         miny = theY[0] - d;
         maxy = theY[0] + d;
      }
   }
   if (theColor) {
      if (minc == maxc) {
         if (theColor[0] == 0.) {
            minc = -e;
            maxc = e;
         } else {
            d = TMath::Abs(theColor[0]*e);
            minc = theColor[0] - d;
            maxc = theColor[0] + d;
         }
      }
   }
   if (theSize) {
      if (mins == maxs) {
         if (theSize[0] == 0.) {
            mins = -e;
            maxs = e;
         } else {
            d = TMath::Abs(theSize[0]*e);
            mins = theSize[0] - d;
            maxs = theSize[0] + d;
         }
      }
   }
 
   TH2F *h = theScatter->GetHistogram();
   if (optionAxis) h->Paint(" ");
 
   // Define and paint palette
   if (theColor) {
      TPaletteAxis *palette;
      TList *functions = theScatter->GetGraph()->GetListOfFunctions();
      palette = (TPaletteAxis*)functions->FindObject("palette");
      TView *view = gPad->GetView();
      if (palette) {
         if (view) {
            if (!palette->TestBit(TPaletteAxis::kHasView)) {
               functions->Remove(palette);
               delete palette; palette = nullptr;
            }
         } else {
            if (palette->TestBit(TPaletteAxis::kHasView)) {
               functions->Remove(palette);
               delete palette; palette = nullptr;
            }
         }
      }
      if (!palette) {
         Double_t xup  = gPad->GetUxmax();
         Double_t x2   = gPad->PadtoX(gPad->GetX2());
         Double_t ymin = gPad->PadtoY(gPad->GetUymin());
         Double_t ymax = gPad->PadtoY(gPad->GetUymax());
         Double_t xr   = 0.05*(gPad->GetX2() - gPad->GetX1());
         Double_t xmin = gPad->PadtoX(xup +0.1*xr);
         Double_t xmax = gPad->PadtoX(xup + xr);
         if (xmax > x2) xmax = gPad->PadtoX(gPad->GetX2()-0.01*xr);
         palette = new TPaletteAxis(xmin,ymin,xmax,ymax,minc,maxc);
         palette->SetLabelColor(h->GetLabelColor());
         palette->SetLabelFont(h->GetLabelFont());
         palette->SetLabelOffset(h->GetLabelOffset());
         palette->SetLabelSize(h->GetLabelSize());
         palette->SetTitleOffset(h->GetTitleOffset());
         palette->SetTitleSize(h->GetTitleSize());
         palette->SetNdivisions(h->GetNdivisions());
         functions->AddFirst(palette);
      }
      if (palette) palette->Paint();
   }
 
   // Draw markers
   auto nbcol = gStyle->GetNumberOfColors();
   int logx = gPad->GetLogx();
   int logy = gPad->GetLogy();
   int logz = gPad->GetLogz();
   if (theColor && logz) {
      if (minc>0) minc = log10(minc);
      if (maxc>0) maxc = log10(maxc);
   }
   theScatter->SetMarkerColor(theScatter->GetMarkerColor());
   theScatter->TAttMarker::Modify();
   double x,y,c,ms;
   int nc;
   for (int i=0; i<n; i++) {
      if (theColor) {
         if (logz) {
            if (theColor[i]>0) c = log10(theColor[i]);
            else continue;
         } else {
            c = theColor[i];
         }
         nc = TMath::Nint(((c-minc)/(maxc-minc))*(nbcol-1));
         if (nc > nbcol-1) nc = nbcol-1;
         theScatter->SetMarkerColor(gStyle->GetColorPalette(nc));
      }
      if (theSize)  {
         ms = (MaxMarkerSize-MinMarkerSize)*((theSize[i]-mins)/(maxs-mins))+MinMarkerSize;
         theScatter->SetMarkerSize(ms);
      }
      if (theColor || theSize) theScatter->TAttMarker::Modify();
      if (logx) {
        if (theX[i]>0) x = log10(theX[i]);
        else break;
      } else {
        x = theX[i];
      }
      if (logy) {
        if (theY[i]>0) y = log10(theY[i]);
        else break;
      } else {
        y = theY[i];
      }
      gPad->PaintPolyMarker(1,&x,&y);
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint a simple graph, without errors bars.
 
void TGraphPainter::PaintGraphSimple(TGraph *theGraph, Option_t *option)
{
   if (strstr(option,"H") || strstr(option,"h")) {
      PaintGrapHist(theGraph, theGraph->GetN(), theGraph->GetX(), theGraph->GetY(), option);
   } else {
      PaintGraph(theGraph, theGraph->GetN(), theGraph->GetX(), theGraph->GetY(), option);
   }
 
   PaintHighlightPoint(theGraph, option);
 
   // Paint associated objects in the list of functions (for instance
   // the fit function).
   TList *functions = theGraph->GetListOfFunctions();
   if (!functions) return;
   auto lnk = functions->FirstLink();
 
   while (lnk) {
      auto obj = lnk->GetObject();
      TVirtualPad::TContext ctxt(true);
      if (obj->InheritsFrom(TF1::Class())) {
         if (obj->TestBit(TF1::kNotDraw) == 0) obj->Paint("lsame");
      } else  {
         obj->Paint(lnk->GetOption());
      }
      lnk = lnk->Next();
   }
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint a polyline with hatches on one side showing an exclusion zone. x and y
/// are the vectors holding the polyline and n the number of points in the
/// polyline and `w` the width of the hatches. `w` can be negative.
/// This method is not meant to be used directly. It is called automatically
/// according to the line style convention.
 
void TGraphPainter::PaintPolyLineHatches(TGraph *theGraph, Int_t n, const Double_t *x, const Double_t *y)
{
 
   Int_t i,j,nf;
   Double_t w = (theGraph->GetLineWidth()/100)*0.005;
 
   std::vector<Double_t> xf(2*n);
   std::vector<Double_t> yf(2*n);
   std::vector<Double_t> xt(n);
   std::vector<Double_t> yt(n);
   Double_t x1, x2, y1, y2, x3, y3, xm, ym, a, a1, a2, a3;
 
   // Compute the gPad coordinates in TRUE normalized space (NDC)
   Int_t ix1,iy1,ix2,iy2;
   Int_t iw = gPad->GetWw();
   Int_t ih = gPad->GetWh();
   Double_t x1p,y1p,x2p,y2p;
   gPad->GetPadPar(x1p,y1p,x2p,y2p);
   ix1 = (Int_t)(iw*x1p);
   iy1 = (Int_t)(ih*y1p);
   ix2 = (Int_t)(iw*x2p);
   iy2 = (Int_t)(ih*y2p);
   Double_t wndc  = TMath::Min(1.,(Double_t)iw/(Double_t)ih);
   Double_t hndc  = TMath::Min(1.,(Double_t)ih/(Double_t)iw);
   Double_t rh    = hndc/(Double_t)ih;
   Double_t rw    = wndc/(Double_t)iw;
   Double_t x1ndc = (Double_t)ix1*rw;
   Double_t y1ndc = (Double_t)iy1*rh;
   Double_t x2ndc = (Double_t)ix2*rw;
   Double_t y2ndc = (Double_t)iy2*rh;
 
   // Ratios to convert user space in TRUE normalized space (NDC)
   Double_t rx1,ry1,rx2,ry2;
   gPad->GetRange(rx1,ry1,rx2,ry2);
   Double_t rx = (x2ndc-x1ndc)/(rx2-rx1);
   Double_t ry = (y2ndc-y1ndc)/(ry2-ry1);
 
   // The first part of the filled area is made of the graph points.
   // Make sure that two adjacent points are different.
   xf[0] = rx*(x[0]-rx1)+x1ndc;
   yf[0] = ry*(y[0]-ry1)+y1ndc;
   nf = 0;
   for (i=1; i<n; i++) {
      if (x[i]==x[i-1] && y[i]==y[i-1]) continue;
      nf++;
      xf[nf] = rx*(x[i]-rx1)+x1ndc;
      if (xf[i]==xf[i-1]) xf[i] += 0.000001; // add an epsilon to avoid exact vertical lines.
      yf[nf] = ry*(y[i]-ry1)+y1ndc;
   }
 
   // For each graph points a shifted points is computed to build up
   // the second part of the filled area. First and last points are
   // treated as special cases, outside of the loop.
   if (xf[1]==xf[0]) {
      a = TMath::PiOver2();
   } else {
      a = TMath::ATan((yf[1]-yf[0])/(xf[1]-xf[0]));
   }
   if (xf[0]<=xf[1]) {
      xt[0] = xf[0]-w*TMath::Sin(a);
      yt[0] = yf[0]+w*TMath::Cos(a);
   } else {
      xt[0] = xf[0]+w*TMath::Sin(a);
      yt[0] = yf[0]-w*TMath::Cos(a);
   }
 
   if (xf[nf]==xf[nf-1]) {
      a = TMath::PiOver2();
   } else {
      a = TMath::ATan((yf[nf]-yf[nf-1])/(xf[nf]-xf[nf-1]));
   }
   if (xf[nf]>=xf[nf-1]) {
      xt[nf] = xf[nf]-w*TMath::Sin(a);
      yt[nf] = yf[nf]+w*TMath::Cos(a);
   } else {
      xt[nf] = xf[nf]+w*TMath::Sin(a);
      yt[nf] = yf[nf]-w*TMath::Cos(a);
   }
 
   Double_t xi0,yi0,xi1,yi1,xi2,yi2;
   for (i=1; i<nf; i++) {
      xi0 = xf[i];
      yi0 = yf[i];
      xi1 = xf[i+1];
      yi1 = yf[i+1];
      xi2 = xf[i-1];
      yi2 = yf[i-1];
      if (xi1==xi0) {
         a1 = TMath::PiOver2();
      } else {
         a1  = TMath::ATan((yi1-yi0)/(xi1-xi0));
      }
      if (xi1<xi0) a1 = a1+3.14159;
      if (xi2==xi0) {
         a2 = TMath::PiOver2();
      } else {
         a2  = TMath::ATan((yi0-yi2)/(xi0-xi2));
      }
      if (xi0<xi2) a2 = a2+3.14159;
      x1 = xi0-w*TMath::Sin(a1);
      y1 = yi0+w*TMath::Cos(a1);
      x2 = xi0-w*TMath::Sin(a2);
      y2 = yi0+w*TMath::Cos(a2);
      xm = (x1+x2)*0.5;
      ym = (y1+y2)*0.5;
      if (xm==xi0) {
         a3 = TMath::PiOver2();
      } else {
         a3 = TMath::ATan((ym-yi0)/(xm-xi0));
      }
      x3 = xi0-w*TMath::Sin(a3+1.57079);
      y3 = yi0+w*TMath::Cos(a3+1.57079);
      // Rotate (x3,y3) by PI around (xi0,yi0) if it is not on the (xm,ym) side.
      if ((xm-xi0)*(x3-xi0)<0 && (ym-yi0)*(y3-yi0)<0) {
         x3 = 2*xi0-x3;
         y3 = 2*yi0-y3;
      }
      if ((xm==x1) && (ym==y1)) {
         x3 = xm;
         y3 = ym;
      }
      xt[i] = x3;
      yt[i] = y3;
   }
 
   // Close the polygon if the first and last points are the same
   if (xf[nf]==xf[0] && yf[nf]==yf[0]) {
      xm = (xt[nf]+xt[0])*0.5;
      ym = (yt[nf]+yt[0])*0.5;
      if (xm==xf[0]) {
         a3 = TMath::PiOver2();
      } else {
         a3 = TMath::ATan((ym-yf[0])/(xm-xf[0]));
      }
      x3 = xf[0]+w*TMath::Sin(a3+1.57079);
      y3 = yf[0]-w*TMath::Cos(a3+1.57079);
      if ((xm-xf[0])*(x3-xf[0])<0 && (ym-yf[0])*(y3-yf[0])<0) {
         x3 = 2*xf[0]-x3;
         y3 = 2*yf[0]-y3;
      }
      xt[nf] = x3;
      xt[0]  = x3;
      yt[nf] = y3;
      yt[0]  = y3;
   }
 
   // Find the crossing segments and remove the useless ones
   Double_t xc, yc, c1, b1, c2, b2;
   Bool_t cross = kFALSE;
   Int_t nf2 = nf;
   for (i=nf2; i>0; i--) {
      for (j=i-1; j>0; j--) {
         if (xt[i-1]==xt[i] || xt[j-1]==xt[j]) continue;
         c1  = (yt[i-1]-yt[i])/(xt[i-1]-xt[i]);
         b1  = yt[i]-c1*xt[i];
         c2  = (yt[j-1]-yt[j])/(xt[j-1]-xt[j]);
         b2  = yt[j]-c2*xt[j];
         if (c1 != c2) {
            xc = (b2-b1)/(c1-c2);
            yc = c1*xc+b1;
            if (xc>TMath::Min(xt[i],xt[i-1]) && xc<TMath::Max(xt[i],xt[i-1]) &&
                xc>TMath::Min(xt[j],xt[j-1]) && xc<TMath::Max(xt[j],xt[j-1]) &&
                yc>TMath::Min(yt[i],yt[i-1]) && yc<TMath::Max(yt[i],yt[i-1]) &&
                yc>TMath::Min(yt[j],yt[j-1]) && yc<TMath::Max(yt[j],yt[j-1])) {
               nf++; xf[nf] = xt[i]; yf[nf] = yt[i];
               nf++; xf[nf] = xc   ; yf[nf] = yc;
               i = j;
               cross = kTRUE;
               break;
            } else {
               continue;
            }
         } else {
            continue;
         }
      }
      if (!cross) {
         nf++;
         xf[nf] = xt[i];
         yf[nf] = yt[i];
      }
      cross = kFALSE;
   }
   nf++; xf[nf] = xt[0]; yf[nf] = yt[0];
 
   // NDC to user coordinates
   for (i=0; i<nf+1; i++) {
      xf[i] = (1/rx)*(xf[i]-x1ndc)+rx1;
      yf[i] = (1/ry)*(yf[i]-y1ndc)+ry1;
   }
 
   // Draw filled area
   gPad->PaintFillArea(nf+1,xf.data(),yf.data());
   theGraph->TAttLine::Modify(); // In case of PaintFillAreaHatches
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Paint the statistics box with the fit info.
 
void TGraphPainter::PaintStats(TGraph *theGraph, TF1 *fit)
{
 
   Int_t dofit;
   TPaveStats *stats  = nullptr;
   TList *functions = theGraph->GetListOfFunctions();
   TIter next(functions);
   while (auto obj = next()) {
      if (obj->InheritsFrom(TPaveStats::Class())) {
         stats = (TPaveStats*)obj;
         break;
      }
   }
 
   if (stats) dofit  = stats->GetOptFit();
   else       dofit  = gStyle->GetOptFit();
 
   if (!dofit) fit = nullptr;
   if (!fit) return;
   if (dofit  == 1) dofit  =  111;
   Int_t nlines = 0;
   Int_t print_fval    = dofit%10;
   Int_t print_ferrors = (dofit/10)%10;
   Int_t print_fchi2   = (dofit/100)%10;
   Int_t print_fprob   = (dofit/1000)%10;
   Int_t nlinesf = print_fval + print_fchi2 + print_fprob;
   if (fit) {
      if (print_fval < 2) nlinesf += fit->GetNumberFreeParameters();
      else                nlinesf += fit->GetNpar();
   }
   Bool_t done = kFALSE;
   Double_t  statw  = 1.8*gStyle->GetStatW();
   Double_t  stath  = 0.25*(nlines+nlinesf)*gStyle->GetStatH();
   if (stats) {
      stats->Clear();
      done = kTRUE;
   } else {
      stats  = new TPaveStats(
               gStyle->GetStatX()-statw,
               gStyle->GetStatY()-stath,
               gStyle->GetStatX(),
               gStyle->GetStatY(),"brNDC");
 
      stats->SetParent(functions);
      stats->SetOptFit(dofit);
      stats->SetOptStat(0);
      stats->SetFillColor(gStyle->GetStatColor());
      stats->SetFillStyle(gStyle->GetStatStyle());
      stats->SetBorderSize(gStyle->GetStatBorderSize());
      stats->SetTextFont(gStyle->GetStatFont());
      if (gStyle->GetStatFont()%10 > 2)
         stats->SetTextSize(gStyle->GetStatFontSize());
      stats->SetFitFormat(gStyle->GetFitFormat());
      stats->SetStatFormat(gStyle->GetStatFormat());
      stats->SetName("stats");
 
      stats->SetTextColor(gStyle->GetStatTextColor());
      stats->SetTextAlign(12);
      stats->SetBit(kCanDelete);
      stats->SetBit(kMustCleanup);
   }
 
   char t[64];
   char textstats[50];
   Int_t ndf = fit->GetNDF();
   snprintf(textstats,50,"#chi^{2} / ndf = %s%s / %d","%",stats->GetFitFormat(),ndf);
   snprintf(t,64,textstats,fit->GetChisquare());
   if (print_fchi2) stats->AddText(t);
   if (print_fprob) {
      snprintf(textstats,50,"Prob  = %s%s","%",stats->GetFitFormat());
      snprintf(t,64,textstats,TMath::Prob(fit->GetChisquare(),ndf));
      stats->AddText(t);
   }
   if (print_fval || print_ferrors) {
      Double_t parmin,parmax;
      for (Int_t ipar=0;ipar<fit->GetNpar();ipar++) {
         fit->GetParLimits(ipar,parmin,parmax);
         if (print_fval < 2 && parmin*parmax != 0 && parmin >= parmax) continue;
         if (print_ferrors) {
            snprintf(textstats,50,"%-8s = %s%s #pm %s%s ",fit->GetParName(ipar),"%",stats->GetFitFormat(),"%",stats->GetFitFormat());
            snprintf(t,64,textstats,fit->GetParameter(ipar)
                            ,fit->GetParError(ipar));
         } else {
            snprintf(textstats,50,"%-8s = %s%s ",fit->GetParName(ipar),"%",stats->GetFitFormat());
            snprintf(t,64,textstats,fit->GetParameter(ipar));
         }
         t[63] = 0;
         stats->AddText(t);
      }
   }
 
   if (!done) functions->Add(stats);
   stats->Paint();
}
 
 
////////////////////////////////////////////////////////////////////////////////
/// Smooth a curve given by N points.
///
/// The original code is from an underlaying routine for Draw based on the
/// CERN GD3 routine TVIPTE:
///
/// Author - Marlow etc.   Modified by - P. Ward     Date -  3.10.1973
///
/// This method draws a smooth tangentially continuous curve through
/// the sequence of data points P(I) I=1,N where P(I)=(X(I),Y(I)).
/// The curve is approximated by a polygonal arc of short vectors.
/// The data points can represent open curves, P(1) != P(N) or closed
/// curves P(2) == P(N). If a tangential discontinuity at P(I) is
/// required, then set P(I)=P(I+1). Loops are also allowed.
///
/// Reference Marlow and Powell, Harwell report No.R.7092.1972
/// MCCONALOGUE, Computer Journal VOL.13, NO4, NOV1970P p392 6
///
/// -  npoints   : Number of data points.
/// -  x         : Abscissa
/// -  y         : Ordinate
 
void TGraphPainter::Smooth(TGraph *theGraph, Int_t npoints, Double_t *x, Double_t *y, Int_t drawtype)
{
 
   Int_t i, k, kp, km, npointsMax, banksize, n2, npt;
   Int_t maxiterations, finished;
   Int_t jtype, ktype, closed;
   Double_t sxmin, sxmax, symin, symax;
   Double_t delta;
   Double_t xorg, yorg;
   Double_t ratio_signs, xratio, yratio;
   Int_t flgic, flgis;
   Int_t iw, loptx;
   Double_t p1, p2, p3, p4, p5, p6;
   Double_t w1, w2, w3;
   Double_t a, b, c, r, s=0.0, t, z;
   Double_t co, so, ct, st, ctu, stu, xnt;
   Double_t dx1, dy1, dx2, dy2, dk1, dk2;
   Double_t xo, yo, dx, dy, xt, yt;
   Double_t xa, xb, ya, yb;
   Double_t u1, u2, u3, tj;
   Double_t cc, err;
   Double_t sb, sth;
   Double_t wsign, tsquare, tcube;
   c = t = co = so = ct = st = ctu = stu = dx1 = dy1 = dx2 = dy2 = 0;
   xt = yt = xa = xb = ya = yb = u1 = u2 = u3 = tj = sb = 0;
 
   npointsMax  = npoints*10;
   n2          = npointsMax-2;
   banksize    = n2;
 
   std::vector<Double_t> qlx(npointsMax);
   std::vector<Double_t> qly(npointsMax);
   if (qlx.empty() || qly.empty()) {
      Error("Smooth", "not enough space in memory");
      return;
   }
 
   //  Decode the type of curve (draw type).
 
   loptx = kFALSE;
   jtype  = (drawtype%1000)-10;
   if (jtype > 0) { ktype = jtype; loptx = kTRUE; }
   else             ktype = drawtype%1000;
 
   Double_t ruxmin = gPad->GetUxmin();
   Double_t ruymin = gPad->GetUymin();
   if (ktype == 3) {
      xorg = ruxmin;
      yorg = ruymin;
   } else {
      xorg = TMath::Max((Double_t)0,ruxmin);
      yorg = TMath::Min(TMath::Max((Double_t)0,ruymin),gPad->GetUymax());
   }
 
   // delta is the accuracy required in constructing the curve.
   // If it is zero then the routine calculates a value otherwise
   // it uses this value. (default is 0.0)
 
   delta         = 0.00055;
   maxiterations = 20;
 
   //       Scale data to the range 0-ratio_signs in X, 0-1 in Y
   //       where ratio_signs is the ratio between the number of changes
   //       of sign in Y divided by the number of changes of sign in X
 
   sxmin = x[0];
   sxmax = x[0];
   symin = y[0];
   symax = y[0];
   Double_t six   = 1;
   Double_t siy   = 1;
   for (i=1;i<npoints;i++) {
      if (i > 1) {
         if ((x[i]-x[i-1])*(x[i-1]-x[i-2]) < 0) six++;
         if ((y[i]-y[i-1])*(y[i-1]-y[i-2]) < 0) siy++;
      }
      if (x[i] < sxmin) sxmin = x[i];
      if (x[i] > sxmax) sxmax = x[i];
      if (y[i] < symin) symin = y[i];
      if (y[i] > symax) symax = y[i];
   }
   closed = 0;
   Double_t dx1n   = TMath::Abs(x[npoints-1]-x[0]);
   Double_t dy1n   = TMath::Abs(y[npoints-1]-y[0]);
   if (dx1n < 0.01*(sxmax-sxmin) && dy1n < 0.01*(symax-symin))  closed = 1;
   if (sxmin == sxmax) {
      xratio = 1;
   } else {
      if (six > 1) ratio_signs = siy/six;
      else         ratio_signs = 20;
      xratio = ratio_signs/(sxmax-sxmin);
   }
   if (symin == symax) yratio = 1;
   else                yratio = 1/(symax-symin);
 
   qlx[0] = x[0];
   qly[0] = y[0];
   for (i=0;i<npoints;i++) {
      x[i] = (x[i]-sxmin)*xratio;
      y[i] = (y[i]-symin)*yratio;
   }
 
   //          "finished" is minus one if we must draw a straight line from P(k-1)
   //          to P(k). "finished" is one if the last call to PaintPolyLine has < n2
   //          points. "finished" is zero otherwise. npt counts the X and Y
   //          coordinates in work . When npt=n2 a call to IPL is made.
 
   finished = 0;
   npt      = 1;
   k        = 1;
 
   //           Convert coordinates back to original system
 
   //           Separate the set of data points into arcs P(k-1),P(k).
   //           Calculate the direction cosines. first consider whether
   //           there is a continuous tangent at the endpoints.
 
   if (!closed) {
      if (x[0] != x[npoints-1] || y[0] != y[npoints-1]) goto L40;
      if (x[npoints-2] == x[npoints-1] && y[npoints-2] == y[npoints-1]) goto L40;
      if (x[0] == x[1] && y[0] == y[1]) goto L40;
   }
   flgic = kFALSE;
   flgis = kTRUE;
 
   //           flgic is true if the curve is open and false if it is closed.
   //           flgis is true in the main loop, but is false if there is
   //           a deviation from the main loop.
 
   km = npoints - 1;
 
   //           Calculate direction cosines at P(1) using P(N-1),P(1),P(2).
 
   goto L100;
L40:
   flgic = kTRUE;
   flgis = kFALSE;
 
   //           Skip excessive consecutive equal points.
 
L50:
   if (k >= npoints) {
      finished = 1;  // Prepare to clear out remaining short vectors before returning
      if (npt > 1) goto L310;
      goto L390;
   }
   k++;
   if (x[k-1] == x[k-2] && y[k-1] == y[k-2])  goto L50;
L60:
   km = k-1;
   if (k > npoints) {
      finished = 1;  // Prepare to clear out remaining short vectors before returning
      if (npt > 1) goto L310;
      goto L390;
   }
   if (k < npoints) goto L90;
   if (!flgic) { kp = 2; goto L130;}
 
L80:
   if (flgis) goto L150;
 
   //           Draw a straight line from P(k-1) to P(k).
 
   finished = -1;
   goto L170;
 
   //           Test whether P(k) is a cusp.
 
L90:
   if (x[k-1] == x[k] && y[k-1] == y[k]) goto L80;
L100:
   kp = k+1;
   goto L130;
 
   //           Branch if the next section of the curve begins at a cusp.
 
L110:
   if (!flgis) goto L50;
 
   //           Carry forward the direction cosines from the previous arc.
 
L120:
   co = ct;
   so = st;
   k++;
   goto L60;
 
   //           Calculate the direction cosines at P(k).  If k=1 then
   //           N-1 is used for k-1. If k=N then 2 is used for k+1.
   //           direction cosines at P(k) obtained from P(k-1),P(k),P(k+1).
 
L130:
   dx1 = x[k-1]  - x[km-1];
   dy1 = y[k-1]  - y[km-1];
   dk1 = dx1*dx1 + dy1*dy1;
   dx2 = x[kp-1] - x[k-1];
   dy2 = y[kp-1] - y[k-1];
   dk2 = dx2*dx2 + dy2*dy2;
   ctu = dx1*dk2 + dx2*dk1;
   stu = dy1*dk2 + dy2*dk1;
   xnt = ctu*ctu + stu*stu;
 
   //           If both ctu and stu are zero,then default.This can
   //           occur when P(k)=P(k+1). I.E. A loop.
 
   if (xnt < 1.E-25) {
      ctu = dy1;
      stu =-dx1;
      xnt = dk1;
   }
   //           Normalise direction cosines.
 
   ct = ctu/TMath::Sqrt(xnt);
   st = stu/TMath::Sqrt(xnt);
   if (flgis) goto L160;
 
   //           Direction cosines at P(k-1) obtained from P(k-1),P(k),P(k+1).
 
   w3    = 2*(dx1*dy2-dx2*dy1);
   co    = ctu+w3*dy1;
   so    = stu-w3*dx1;
   xnt   = 1/TMath::Sqrt(co*co+so*so);
   co    = co*xnt;
   so    = so*xnt;
   flgis = kTRUE;
   goto L170;
 
   //           Direction cosines at P(k) obtained from P(k-2),P(k-1),P(k).
 
L150:
   w3    = 2*(dx1*dy2-dx2*dy1);
   ct    = ctu-w3*dy2;
   st    = stu+w3*dx2;
   xnt   = 1/TMath::Sqrt(ct*ct+st*st);
   ct    = ct*xnt;
   st    = st*xnt;
   flgis = kFALSE;
   goto L170;
L160:
   if (k <= 1) goto L120;
 
   //           For the arc between P(k-1) and P(k) with direction cosines co,
   //           so and ct,st respectively, calculate the coefficients of the
   //           parametric cubic represented by X(t) and Y(t) where
   //           X(t)=xa*t**3 + xb*t**2 + co*t + xo
   //           Y(t)=ya*t**3 + yb*t**2 + so*t + yo
 
L170:
   xo = x[k-2];
   yo = y[k-2];
   dx = x[k-1] - xo;
   dy = y[k-1] - yo;
 
   //           Initialise the values of X(TI),Y(TI) in xt and yt respectively.
 
   xt = xo;
   yt = yo;
   if (finished < 0) {  // Draw a straight line between (xo,yo) and (xt,yt)
      xt += dx;
      yt += dy;
      goto L300;
   }
   c  = dx*dx+dy*dy;
   a  = co+ct;
   b  = so+st;
   r  = dx*a+dy*b;
   t  = c*6/(TMath::Sqrt(r*r+2*(7-co*ct-so*st)*c)+r);
   tsquare = t*t;
   tcube   = t*tsquare;
   xa = (a*t-2*dx)/tcube;
   xb = (3*dx-(co+a)*t)/tsquare;
   ya = (b*t-2*dy)/tcube;
   yb = (3*dy-(so+b)*t)/tsquare;
 
   //           If the curve is close to a straight line then use a straight
   //           line between (xo,yo) and (xt,yt).
 
   if (.75*TMath::Max(TMath::Abs(dx*so-dy*co),TMath::Abs(dx*st-dy*ct)) <= delta) {
      finished = -1;
      xt += dx;
      yt += dy;
      goto L300;
   }
 
   //           Calculate a set of values 0 == t(0).LTCT(1) <  ...  < t(M)=TC
   //           such that polygonal arc joining X(t(J)),Y(t(J)) (J=0,1,..M)
   //           is within the required accuracy of the curve
 
   tj = 0;
   u1 = ya*xb-yb*xa;
   u2 = yb*co-xb*so;
   u3 = so*xa-ya*co;
 
   //           Given t(J), calculate t(J+1). The values of X(t(J)),
   //           Y(t(J)) t(J) are contained in xt,yt and tj respectively.
 
L180:
   s  = t - tj;
   iw = -2;
 
   //           Define iw here later.
 
   p1 = (2*u1)*tj-u3;
   p2 = (u1*tj-u3)*3*tj+u2;
   p3 = 3*tj*ya+yb;
   p4 = (p3+yb)*tj+so;
   p5 = 3*tj*xa+xb;
   p6 = (p5+xb)*tj+co;
 
   //           Test D(tj,THETA). A is set to (Y(tj+s)-Y(tj))/s.b is
   //           set to (X(tj+s)-X(tj))/s.
 
   cc  = 0.8209285;
   err = 0.1209835;
L190:
   iw -= 2;
L200:
   a   = (s*ya+p3)*s+p4;
   b   = (s*xa+p5)*s+p6;
 
   //           Set z to PSI(D/delta)-cc.
 
   w1 = -s*(s*u1+p1);
   w2 = s*s*u1-p2;
   w3 = 1.5*w1+w2;
 
   //           Set the estimate of (THETA-tj)/s.Then set the numerator
   //           of the expression (EQUATION 4.4)/s. Then set the square
   //           of D(tj,tj+s)/delta. Then replace z by PSI(D/delta)-cc.
 
   if (w3 > 0) wsign = TMath::Abs(w1);
   else        wsign = -TMath::Abs(w1);
   sth = 0.5+wsign/(3.4*TMath::Abs(w1)+5.2*TMath::Abs(w3));
   z   = s*sth*(s-s*sth)*(w1*sth+w1+w2);
   z   = z*z/((a*a+b*b)*(delta*delta));
   z   = (z+2.642937)*z/((.3715652*z+3.063444)*z+.2441889)-cc;
 
   //           Branch if z has been calculated
 
   if (iw > 0) goto L250;
   if (z > err) goto L240;
   goto L220;
L210:
   iw -= 2;
L220:
   if (iw+2 == 0) goto L190;
   if (iw+2 >  0) goto L290;
 
   //           Last part of arc.
 
L230:
   xt = x[k-1];
   yt = y[k-1];
   s  = 0;
   goto L300;
 
   //           z(s). find a value of s where 0 <= s <= sb such that
   //           TMath::Abs(z(s)) < err
 
L240:
   kp = 0;
   c  = z;
   sb = s;
L250:
   theGraph->Zero(kp,0,sb,err,s,z,maxiterations);
   if (kp == 2) goto L210;
   if (kp > 2) {
      Error("Smooth", "Attempt to plot outside plot limits");
      goto L230;
   }
   if (iw > 0) goto L200;
 
   //           Set z=z(s) for s=0.
 
   if (iw < 0) {
      z  = -cc;
      iw = 0;
      goto L250;
   }
 
   //           Set z=z(s) for s=sb.
 
   z  = c;
   iw = 1;
   goto L250;
 
   //           Update tj,xt and yt.
 
L290:
   xt = xt + s*b;
   yt = yt + s*a;
   tj = s  + tj;
 
   //           Convert coordinates to original system
 
L300:
   qlx[npt] = sxmin + xt/xratio;
   qly[npt] = symin + yt/yratio;
   npt++;
 
   //           If a fill area must be drawn and if the banks LX and
   //           LY are too small they are enlarged in order to draw
   //           the filled area in one go.
 
   if (npt < banksize)  goto L320;
   if (drawtype >= 1000 || ktype > 1) {
      Int_t newsize = banksize + n2;
      std::vector<Double_t> qtemp(banksize);
      for (i=0;i<banksize;i++) qtemp[i] = qlx[i];
      qlx.resize(newsize);
      for (i=0;i<banksize;i++) qlx[i]   = qtemp[i];
      for (i=0;i<banksize;i++) qtemp[i] = qly[i];
      qly.resize(newsize);
      for (i=0;i<banksize;i++) qly[i] = qtemp[i];
      banksize = newsize;
      goto L320;
   }
 
   //           Draw the graph
 
L310:
   if (drawtype >= 1000) {
      gPad->PaintFillArea(npt,qlx.data(),qly.data(), "B");
   } else {
      if (ktype > 1) {
         if (!loptx) {
            qlx[npt]   = qlx[npt-1];
            qlx[npt+1] = qlx[0];
            qly[npt]   = yorg;
            qly[npt+1] = yorg;
         } else {
            qlx[npt]   = xorg;
            qlx[npt+1] = xorg;
            qly[npt]   = qly[npt-1];
            qly[npt+1] = qly[0];
         }
         gPad->PaintFillArea(npt+2,qlx.data(),qly.data());
      }
      if (TMath::Abs(theGraph->GetLineWidth())>99) PaintPolyLineHatches(theGraph, npt, qlx.data(), qly.data());
      gPad->PaintPolyLine(npt,qlx.data(),qly.data());
   }
   npt = 1;
   qlx[0] = sxmin + xt/xratio;
   qly[0] = symin + yt/yratio;
L320:
   if (finished > 0) goto L390;
   if (finished < 0) { finished = 0; goto L110;}
   if (s > 0) goto L180;
   goto L110;
 
   //           Convert coordinates back to original system
 
L390:
   for (i=0;i<npoints;i++) {
      x[i] = sxmin + x[i]/xratio;
      y[i] = symin + y[i]/yratio;
   }
 
}
 
////////////////////////////////////////////////////////////////////////////////
/// Static function to set `fgMaxPointsPerLine` for graph painting. When graphs
/// are painted with lines, they are split into chunks of length `fgMaxPointsPerLine`.
/// This allows to paint line with an "infinite" number of points. In some case
/// this "chunks painting" technic may create artefacts at the chunk's boundaries.
/// For instance when zooming deeply in a PDF file. To avoid this effect it might
/// be necessary to increase the chunks' size using this function:
/// `TGraphPainter::SetMaxPointsPerLine(20000)`.
 
void TGraphPainter::SetMaxPointsPerLine(Int_t maxp)
{
   fgMaxPointsPerLine = maxp;
   if (maxp < 50) fgMaxPointsPerLine = 50;
}