Superimposing without drawing

Hi Rooters,
I am trying to output a large number of TH2F's, and I am having the following issue. I am trying to take a data set in a graph, impose two lines on it, and then output the graph as a .gif file. The only way I have found to do this is by drawing the graph, drawing the lines on top, and then printing. This takes a very long time for so many graphs, and it is not needed for this program. The following is a test version of what i'm doing:

{
TCanvas *c1 = new TCanvas("testgraph","testgraph"); TH1F *graph1 = new TH1F("graph1", "graph1", 10, -5, 5); graph1->FillRandom("gaus", 100);
TLine *line1 = new TLine(-3,0,-3,30);
TLine *line2 = new TLine(3,0,3,30);
line1->SetLineColor(6);
line2->SetLineColor(6);
c1->cd();
graph1->Draw();
line1->Draw("SAME");
line2->Draw("SAME");
c1->Print("graph1.gif");
}

What I would like to do is somehow skip the Draw() portion and simply print the canvas, with no output to the screen.

Thanks,
Adam Roe
Northeastern University
CMS Experiment, CERN Received on Tue Sep 05 2006 - 12:24:06 MEST