Exclusion line problem on vertical sections

ROOT
1

Hi
I have encountered a problem where the exclusion fill will switch sides when there are vertical sections.

An example with 3 points:

TH1 *frame = new TH1F("frame","",1000,-1,3);
frame->SetMinimum(-1);
frame->SetMaximum(3);
frame->SetTitle("problems with exclusion plot");
frame->Draw(" ");

TGraph * graph=new TGraph(3);
graph->SetFillColor(3);
graph->SetFillStyle(3001);
graph->SetLineWidth(2000);
graph->SetPoint(0,1.,1.);
graph->SetPoint(1,1.,0);
graph->SetPoint(2,0.,0.);
graph->Draw("*L");

The odd thing is, if I exchange points 0 and 2, and thus the sense of the graph, the issue disappears.
I think the issue should be in TGraphPainter::PaintPolyLineHatches, but I have not figured it out yet.

Root version: 5.32/00, OS: OSX 10.6.8

Any input is greatly appreciated,
Knut

exclusionexample.png696×472 3.74 KB

2

Thanks for reporting. I will check.
a way to bypass it right now would be do:

graph->SetPoint(1,1.0001,0);

3

Yes, some dithering will make it work.
I had not looked at the possibility of looping over the graph, but I got it now.
Thanks!

Knut

4

This is now fixed in the SVN trunk.
Thanks fo reporting.