lego.C

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/// \file
/// \ingroup tutorial_eve_7
///  This example display only points in web browser
///
/// \macro_code
///
 
#include "TRandom.h"
#include <ROOT/REveElement.hxx>
#include <ROOT/REveScene.hxx>
#include <ROOT/REveManager.hxx>
#include <ROOT/REvePointSet.hxx>
 
namespace REX = ROOT::Experimental;
 
REX::REvePointSet *createPointSet(int npoints = 200, float s = 2, int color = 28)
{
   TRandom &r = *gRandom;
 
   REX::REvePointSet *ps = new REX::REvePointSet("MyTestPoints", "list of eve points", npoints);
 
   for (Int_t i = 0; i < npoints; ++i)
      ps->SetNextPoint(r.Uniform(-s, s), r.Uniform(-s, s), r.Uniform(-s, s));
 
   ps->SetMarkerColor(color);
   ps->SetMarkerSize(3 + r.Uniform(1, 2));
   ps->SetMarkerStyle(4);
   return ps;
}
 
void lego()
{
   auto eveMng = REX::REveManager::Create();
 
   // disable default view
   eveMng->GetViewers()->FirstChild()->SetRnrSelf(false);
 
   auto scene = eveMng->SpawnNewScene("Lego", "LegoView");
   auto view = eveMng->SpawnNewViewer("Lego", "");
   view->AddScene(scene);
 
   auto ps = createPointSet(100);
   scene->AddElement(ps);
 
   {
      TPad *p = new TCanvas("LegoPad", "Lego Pad", 800, 400);
      p->SetMargin(0, 0, 0, 0);
 
      // *** Load std CMS calo demo
      const char *histFile = "http://root.cern/files/cms_calo_hist.root";
      TFile::SetCacheFileDir(".");
      auto hf = TFile::Open(histFile, "CACHEREAD");
      auto ecalHist = (TH2F *)hf->Get("ecalLego");
      auto hcalHist = (TH2F *)hf->Get("hcalLego");
 
      THStack *s = new THStack("LegoStack", ""); // "ECal and HCal";
      ecalHist->SetFillColor(kRed);
      ecalHist->GetXaxis()->SetLabelSize(1);
      ecalHist->GetXaxis()->SetTitle("#eta");
      ecalHist->GetYaxis()->SetLabelSize(1);
      ecalHist->GetYaxis()->SetTitle("#varphi");
      ecalHist->GetZaxis()->SetLabelSize(1);
      s->Add(ecalHist);
      hcalHist->SetFillColor(kBlue);
      s->Add(hcalHist);
      p->Add(s);
 
      TGraph2D *line = new TGraph2D(200);
      for (int i = 0; i < 200; ++i)
         line->SetPoint(i, std::cos(i * 0.1), std::sin(i * 0.1), i * 0.25);
      line->SetLineWidth(5);
      line->SetLineColor(kCyan - 2);
      p->Add(line, "LINE");
 
      p->Modified(kTRUE);
 
      TString json(TBufferJSON::ToJSON(p));
 
      ps->SetTitle(TBase64::Encode(json).Data());
 
      s->Draw();
   }
 
   eveMng->Show();
}