Re: Viewpoint in 3D

From: Roger Mason <rmason_at_esd.mun.ca>
Date: Mon, 18 May 2009 07:14:47 -0230

Hello Rene,

Rene Brun <Rene.Brun_at_cern.ch> writes:

> Try this...

I modified your example to try to rotate the viewpoint and I now have this:

{
  TCanvas *c = new TCanvas("c","Graph2D example",0,0,600,400);

  TGraph2D *dt = new TGraph2D("graph.dat");

  gStyle->SetPalette(1);

  Double_t contours[] = {20,40,60,80,100,120,140,160,180,200};

  // Set the canvas range a bit bigger than the x,y data ranges

  c->Range(0,0,160,160); // does not work
  c->SetTheta(84);
  c->SetPhi(45);
  TH2D* h = new TH2D();
  h = dt->GetHistogram();      // Get histo interpolated between
                               // control points in dt.
  h->SetContour(10,contours);     // Set 10 contour levels (default is
  20)
  h->Draw("surf2");            // Draw interpolated points as surface
  h->Draw("cont1 same");       // Contour the surface
  dt->SetMarkerStyle(8);       // Marker for the control points
  dt->Draw("p same");             // Superimpose the control points

  dt->GetZaxis()->SetNdivisions(2);
  //draw text at each point
  Double_t xyz[3], uv[2];
  Int_t np = dt->GetN();
  c->Update();

  TView *view = c->GetView();

  Double_t longit = view->GetLongitude();    Double_t lat = view->GetLatitude();
   Double_t psi = view->GetPsi();

   cout << "Longit: " << longit << " Lat: " << lat << " Psi: " << psi <<    endl;
   Int_t irep;
   // view->SetView(longit,view->GetLatitude(),view->GetPsi(),0);    view->SetView(10,0,100,irep);
   c->Modified();
   c->Update();

//   TText t;
//   t->SetTextSize(0.035);
//   for (Int_t i=0;i<np;i++) {
//      xyz[0] = dt->GetX()[i];
//      xyz[1] = dt->GetY()[i];
//      xyz[2] = dt->GetZ()[i];
//      view->WCtoNDC(xyz,uv);
//      t->DrawText(uv[0]+0.01,uv[1],Form("point %d",i));
//   }

    return c;
}

Using view->SetView() does not change the viewpoint. What am I doing wrong?

Thanks for your help.

Roger Received on Mon May 18 2009 - 11:54:36 CEST