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transp_text.C File Reference

Detailed Description

This macro is based on labels1.C by Rene Brun.

Updated by Timur Pocheptsov to use transparent text. The macro requires OpenGL - either enable by gStyle->SetCanvasPreferGL(kTRUE); or by setting OpenGL.CanvasPreferGL to 1 in $ROOTSYS/etc/system.rootrc.

//Includes for ACLiC (cling does not need them).
#include "TPaveText.h"
#include "TCanvas.h"
#include "TRandom.h"
#include "TError.h"
#include "TColor.h"
#include "TStyle.h"
#include "TH1F.h"
//Aux. functions for tutorials/gl.
#include "customcolorgl.h"
void transp_text()
//1. Try to 'allocate' free indices for our custom colors -
//we can use hard-coded indices like 1001, 1002, 1003 ... but
//I prefer to find free indices in a ROOT's color table
//to avoid possible conflicts with other tutorials.
Int_t indices[2] = {};
Error("transp_text", "failed to create new custom colors");
//2. Create special transparent colors for both pavetext fill color and text color.
const Int_t grayColorIndex = indices[0], blackColorIndex = indices[1];
new TColor(grayColorIndex, 0.8, 0.8, 0.8, "transparent_gray", 0.85);
new TColor(blackColorIndex, 0., 0., 0., "transparent_black", 0.5);
//3. Create a TCanvas.
TCanvas * const c1 = new TCanvas("transparent text","transparent text demo", 10, 10, 900, 500);
if (!c1->UseGL())
::Warning("transp_text", "to use this macro you need OpenGL");
const Int_t nx = 20;
const char *people[nx] = {"Jean","Pierre","Marie","Odile",
TH1F * const h = new TH1F("h4", "test", nx, 0, nx);
for (Int_t i = 0; i < 5000; ++i)
h->Fill(gRandom->Gaus(0.5 * nx, 0.2 * nx));
for (Int_t i = 1; i <= nx; ++i)
h->GetXaxis()->SetBinLabel(i, people[i - 1]);
TPaveText * const pt = new TPaveText(0.3, 0.3, 0.98, 0.98, "brNDC");
//Transparent 'rectangle' with transparent text.
#define h(i)
Definition: RSha256.hxx:106
int Int_t
Definition: RtypesCore.h:45
const Bool_t kTRUE
Definition: RtypesCore.h:100
void Error(const char *location, const char *msgfmt,...)
Use this function in case an error occurred.
Definition: TError.cxx:187
void Warning(const char *location, const char *msgfmt,...)
Use this function in warning situations.
Definition: TError.cxx:231
R__EXTERN TRandom * gRandom
Definition: TRandom.h:62
R__EXTERN TStyle * gStyle
Definition: TStyle.h:413
virtual void SetFillColor(Color_t fcolor)
Set the fill area color.
Definition: TAttFill.h:37
virtual void SetTextAlign(Short_t align=11)
Set the text alignment.
Definition: TAttText.h:41
virtual void SetTextColor(Color_t tcolor=1)
Set the text color.
Definition: TAttText.h:43
virtual void SetTextSize(Float_t tsize=1)
Set the text size.
Definition: TAttText.h:46
The Canvas class.
Definition: TCanvas.h:23
The color creation and management class.
Definition: TColor.h:19
1-D histogram with a float per channel (see TH1 documentation)}
Definition: TH1.h:575
A Pave (see TPave) with text, lines or/and boxes inside.
Definition: TPaveText.h:21
virtual TText * AddText(Double_t x1, Double_t y1, const char *label)
Add a new Text line to this pavetext at given coordinates.
Definition: TPaveText.cxx:183
virtual void Draw(Option_t *option="")
Draw this pavetext with its current attributes.
Definition: TPaveText.cxx:234
virtual Double_t Gaus(Double_t mean=0, Double_t sigma=1)
Samples a random number from the standard Normal (Gaussian) Distribution with the given mean and sigm...
Definition: TRandom.cxx:274
void SetCanvasPreferGL(Bool_t prefer=kTRUE)
Definition: TStyle.h:325
TPaveText * pt
return c1
Definition: legend1.C:41
unsigned FindFreeCustomColorIndices(T(&indices)[N])
Definition: customcolorgl.h:40
Timur Pocheptsov

Definition in file transp_text.C.