%%cpp -d
#include "RooRealVar.h"
#include "RooDataSet.h"
#include "RooGaussian.h"
#include "TCanvas.h"
#include "TAxis.h"
#include "RooPlot.h"
#include "TText.h"
#include "TArrow.h"
#include "TFile.h"
using namespace RooFit;

RooRealVar x("x", "x", -10, 10);

RooRealVar sigma("sigma", "sigma", 1, 0.1, 10);
RooRealVar mean("mean", "mean", -3, -10, 10);
RooGaussian gauss("gauss", "gauss", x, mean, sigma);

std::unique_ptr<RooDataSet> data{gauss.generate(x, 1000)};

gauss.fitTo(*data, PrintLevel(-1));

RooPlot *frame = x.frame(Name("xframe"), Title("RooPlot with decorations"), Bins(40));
data->plotOn(frame);
gauss.plotOn(frame);

gauss.paramOn(frame, Layout(0.55));

data->statOn(frame, Layout(0.55, 0.99, 0.8));

TText *txt = new TText(2, 100, "Signal");
txt->SetTextSize(0.04);
txt->SetTextColor(kRed);
frame->addObject(txt);

TArrow *arrow = new TArrow(2, 100, -1, 50, 0.01, "|>");
arrow->SetLineColor(kRed);
arrow->SetFillColor(kRed);
arrow->SetLineWidth(3);
frame->addObject(arrow);

TFile f("rf106_plotdecoration.root", "RECREATE");
frame->Write();
f.Close();

new TCanvas("rf106_plotdecoration", "rf106_plotdecoration", 600, 600);
gPad->SetLeftMargin(0.15);
frame->GetYaxis()->SetTitleOffset(1.6);
frame->Draw();

%jsroot on
gROOT->GetListOfCanvases()->Draw()