Applying a watermark-like effect

ROOT
1

Hello Rooters,
Myself and some of my colleagues have wondering if there is anyway to apply a watermark-like effect so out ROOT output.
But this I mean that the end result would have something like PRELIMINARY printed across the slide, but transparent so that you can still see what lies beneath the text.
I know there are various image editors for this sort of thing, but being able to apply this effect directly would save a huge amount of time and effort.

My thanks,
Scott MacEwan
Mount Allison University

2

The is no easy way to make transparent text right now. I can suggest you something like:

{
   hpx->SetFillColor(1);
   hpx->SetFillStyle(3004);
   hpx->Draw("");

   tex = new TLatex(-4.224138,-76.55602,"Very Preliminary");
   tex->SetTextColor(17);
   tex->SetTextSize(0.1991525);
   tex->SetTextAngle(26.15998);
   tex->SetLineWidth(2);
   tex->Draw();
   hpx->Draw("SAME");
   gPad->RedrawAxis();
}

Which gives the attached plot. Transparent text (outline) would requite more work. Do you want it on screen or on PostScript ? or both ?

c1.gif696×472 15.5 KB

3

Many thanks, couet, for your quick reply.
Is it possible to get such an effect on a set of data points as opposed to a histogram? I’ll be honest, I’m acting as the middleman here for a colleague who does not have access to these forums.
Also, he says that he uses .eps for output and really only needs it there.
Thanks again for your swift response.
Scott MacEwan
Mount Allison University

4

I guess what you mean by “Data Points” is TGraph ? The idea is the same as for histograms, first you draw the frame (axis), then you draw on top the large text with some light color, then you draw the graphs, and finally you redraw the axis which have been damaged. The following macro is an example:

{
   const Int_t n = 10;
   Double_t x[n], y[n];
   for (Int_t i=0;i<n;i++) {
      x[i] = i*0.1; 
      y[i] = 10*sin(x[i]+0.2);
   }
   gr = new TGraph(n,x,y);
   gr->SetMarkerStyle(20);
   gr->SetMarkerColor(kBlue);
   gr->Draw("AP");

   tex = new TLatex(0.,3.,"Very Preliminary");              
   tex->SetTextColor(17);
   tex->SetTextSize(0.1991525);
   tex->SetTextAngle(26.15998);
   tex->SetLineWidth(2);
   tex->Draw(); 

   gr->Draw("LP");
   gPad->RedrawAxis();
}

It gives the following output:

c1.gif696×472 10.3 KB

5

Great! Thank you very much for your help.
It never ceases to amaze me the amount of support there is for ROOT!