/*
 * The modified version of original DynamicSlice.C macro for gamma-gamma matrices.
 * The X & Y projections corresponding to the cursor position are calculated
 * and displayed on two canvases. The peaks above "threshold" are labeled
 * with their energies. It is assumed that the 2D-histogram has 0.5 keV/bin
 * calibration.
 *
 *
 * Dr. Ajay Y. Deo
 * Dept. of Physics,
 * IIT Roorkee, INDIA
 * ajay.deo@ph.iitr.ac.in
 *
 * July 2, 2020
 *
 *
 * To run this macro:
 * 	First load the root file containing 2D-Histogram
 * 	and then execute it as:
 *
 * 	root[].x DynamicSlice_GG_v1.C
 *
 *
 */

void DynamicSlice_GG_v1()
{
   // Create a new canvas.
   TCanvas* c1 = new TCanvas("c1","Dynamic Slicer",10,10,700,500);

   //TFile *f = new TFile("gg_DySl.root");
   TFile *f = new TFile("test54.root");
  
   //TH2F *his2D_wb = (TH2F*)gROOT->FindObject("his2D_wb");
   TH2F *his2D_wb = (TH2F*)gROOT->FindObject("his2D_clean");
   his2D_wb->GetXaxis()->SetRangeUser(100., 2000.);
   his2D_wb->GetYaxis()->SetRangeUser(100., 2000.);
   
   Double_t xmin = his2D_wb->GetXaxis()->GetXmin();
   Double_t xmax = his2D_wb->GetXaxis()->GetXmax();
   
   Double_t new_xmin = xmin/2;
   Double_t new_xmax = xmax/2;
   
   his2D_wb->GetXaxis()->SetLimits(new_xmin, new_xmax);
   his2D_wb->GetYaxis()->SetLimits(new_xmin, new_xmax);
   
   his2D_wb->Draw("colz");

   //Add a TExec object to the canvas
   c1->AddExec("dynamic","DynamicExec()");
   c1->SetLogz();
   c1->Update();

   gPad->SetCrosshair();
}

void DynamicExec()
{
   // Example of function called when a mouse event occurs in a pad.
   // When moving the mouse in the canvas, a second canvas shows the
   // projection along X(/Y) of the bin corresponding to the Y(/X) position
   // of the mouse. The crosshair cursor shows the current bin position in Y(/X).

   TObject *select = gPad->GetSelected();
   if(!select) return;
   if (!select->InheritsFrom(TH2::Class())) {gPad->SetUniqueID(0); return;}
   TH2 *h = (TH2*)select;
   gPad->GetCanvas()->FeedbackMode(kTRUE);

   int px = gPad->GetEventX();
   int py = gPad->GetEventY();

   Float_t upy = gPad->AbsPixeltoY(py);
   Float_t y = gPad->PadtoY(upy);
   Float_t upx = gPad->AbsPixeltoX(px);
   Float_t x = gPad->PadtoX(upx);

   //create or set the new canvas c2
   //TVirtualPad *padsav = gPad;
   TCanvas *c2 = (TCanvas*)gROOT->GetListOfCanvases()->FindObject("c2");
   if(c2) delete c2->GetPrimitive("Projection");
   else   c2 = new TCanvas("c2","X-Projection Canvas",710,10,700,500);
   c2->SetGrid();
   c2->cd();

   //draw slice corresponding to mouse position
   Int_t biny = h->GetYaxis()->FindBin(y);
   TH1D *hp = h->ProjectionX("",biny-4,biny+4);
   hp->SetFillColor(38);
   char title[80];
   sprintf(title,"X-Projection of %d keV from %d to %d", (biny/2), ((biny-4)/2), ((biny+4)/2));
   hp->SetName("Projection");
   hp->SetTitle(title);
   hp->Draw();

      Int_t npeaks = 100;
      Double_t threshold = 0.1;
      TSpectrum *s = new TSpectrum(2*npeaks);
      Int_t nfound = s->Search(hp,3,"",threshold);
      Double_t *xfound;
      xfound = s->GetPositionX();

      Double_t pPosition[nfound];
      Double_t pHeight[nfound];

      for(Int_t p=0; p<nfound;p++){
          pPosition[p] = xfound[p];
          Int_t xbin = hp->GetXaxis()->FindBin(pPosition[p]);
          pHeight[p] = hp->GetBinContent(xbin);

	  TText *t1 = new TText(pPosition[p]-1,pHeight[p]*0.90,Form("%g",pPosition[p]));

          t1->SetTextAngle(90);
          t1->SetTextColor(kBlue);
          t1->SetTextSize(0.03);
          t1->Draw();
      }

          TList *functions = hp->GetListOfFunctions();
          TPolyMarker *pm = (TPolyMarker*)functions->FindObject("TPolyMarker");
          functions->Remove(pm);
   c2->Update();
   //padsav->cd();

   //create or set the new canvas c3
   //TVirtualPad *padsav2 = gPad;
   TCanvas *c3 = (TCanvas*)gROOT->GetListOfCanvases()->FindObject("c3");
   if(c3) delete c3->GetPrimitive("yProjection");
   else   c3 = new TCanvas("c3","Y-Projection Canvas",710,10,700,500);
   c3->SetGrid();
   c3->cd();

   //draw slice corresponding to mouse position
   Int_t binx = h->GetXaxis()->FindBin(x);
   TH1D *hpy = h->ProjectionY("",binx-4,binx+4);
   hpy->SetFillColor(38);
   char title2[80];
   sprintf(title2,"Y-Projection of %d keV from %d to %d", (binx/2), ((binx-4)/2), ((binx+4)/2));
   hpy->SetName("yProjection");
   hpy->SetTitle(title2);
   hpy->Draw();

      Int_t npeaks2 = 100;
      Double_t threshold2 = 0.1;
      TSpectrum *s2 = new TSpectrum(2*npeaks2);
      Int_t nfound2 = s2->Search(hpy,3,"",threshold2);
      Double_t *xfound2;
      xfound2 = s2->GetPositionX();

      Double_t pPosition2[nfound2];
      Double_t pHeight2[nfound2];

      for(Int_t p=0; p<nfound2;p++){
          pPosition2[p] = xfound2[p];
          Int_t xbin2 = hpy->GetXaxis()->FindBin(pPosition2[p]);
          pHeight2[p] = hpy->GetBinContent(xbin2);

	  TText *t2 = new TText(pPosition2[p]-1,pHeight2[p]*0.90,Form("%g",pPosition2[p]));

          t2->SetTextAngle(90);
          t2->SetTextColor(kBlue);
          t2->SetTextSize(0.03);
          t2->Draw();
      }

          TList *functions2 = hpy->GetListOfFunctions();
          TPolyMarker *pm2 = (TPolyMarker*)functions2->FindObject("TPolyMarker");
          functions2->Remove(pm2);
   c3->Update();

   //padsav2->cd();
}