Logo ROOT   6.21/01
Reference Guide
glvox1.C
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1 /// \file
2 /// \ingroup tutorial_gl
3 /// This macro demonstrates how to use "glcol" option for TH3.
4 ///
5 /// \macro_image(nobatch)
6 /// \macro_code
7 ///
8 /// \author Timur Pocheptsov
9 
10 void glvox1()
11 {
12  //Create and fill TH3.
13  const UInt_t nX = 30;
14  const Double_t xMin = -1., xMax = 1., xStep = (xMax - xMin) / (nX - 1);
15 
16  const UInt_t nY = 30;
17  const Double_t yMin = -1., yMax = 1., yStep = (yMax - yMin) / (nY - 1);
18 
19  const UInt_t nZ = 30;
20  const Double_t zMin = -1., zMax = 1., zStep = (zMax - zMin) / (nZ - 1);
21 
22  TH3F *hist = new TH3F("glvoxel", "glvoxel", 30, -1., 1., 30, -1., 1., 30, -1., 1.);
23 
24  //Fill the histogram to create a "sphere".
25  for (UInt_t i = 0; i < nZ; ++i) {
26  const Double_t z = zMin + i * zStep;
27 
28  for (UInt_t j = 0; j < nY; ++j) {
29  const Double_t y = yMin + j * yStep;
30 
31  for (UInt_t k = 0; k < nX; ++k) {
32  const Double_t x = xMin + k * xStep;
33 
34  const Double_t val = 1. - (x * x + y * y + z * z);
35  hist->SetBinContent(k + 1, j + 1, i + 1, val);
36  }
37  }
38  }
39 
41 
42  hist->Draw("glcol");
43 }
3-D histogram with a float per channel (see TH1 documentation)}
Definition: TH3.h:267
virtual void SetBinContent(Int_t bin, Double_t content)
Set bin content.
Definition: TH3.cxx:3198
R__EXTERN TStyle * gStyle
Definition: TStyle.h:410
Double_t x[n]
Definition: legend1.C:17
void SetCanvasPreferGL(Bool_t prefer=kTRUE)
Definition: TStyle.h:323
virtual void Draw(Option_t *option="")
Draw this histogram with options.
Definition: TH1.cxx:2981
unsigned int UInt_t
Definition: RtypesCore.h:42
double Double_t
Definition: RtypesCore.h:55
Double_t y[n]
Definition: legend1.C:17
you should not use this method at all Int_t Int_t z
Definition: TRolke.cxx:630