Re: animation

Rene Brun (Rene.Brun@cern.ch)
Mon, 10 May 1999 10:57:12 +0000


Hi Feodor,
Below, you will find an example of a macro producing an animated
picture.
It uses the TTimer class. You can adapt it to your needs replacing
the 2-d function TF2 by a TGraph or equivalent.

Rene Brun

///macro anim.C
Double_t pi;
TF2 *f2;
Float_t t = 0;
Float_t phi = 30;
void anim()
{
gStyle->SetFrameFillColor(42);
TCanvas *c1 = new TCanvas("c1");
c1->SetFillColor(17);
pi = TMath::Pi();
f2 = new TF2("f2","sin(2*x)*sin(2*y)*[0]",0,pi,0,pi);
f2->SetParameter(0,1);
f2->SetNpx(15);
f2->SetNpy(15);
f2->SetMaximum(1);
f2->SetMinimum(-1);
f2->Draw("surf1");
TTimer *timer = new TTimer(20);
timer->SetCommand("Animate()");
timer->TurnOn();
}
void Animate()
{
t += 0.05*pi;
f2->SetParameter(0,TMath::Cos(t));
phi += 2;
gPad->SetPhi(phi);
gPad->Modified();
gPad->Update();
}

Feodor Ogrin wrote:
>
> Hi everyone,
>
> I've just joined the ROOTcompany, so I am full of stupied questions which
> I hope you do not mind to help me with.
>
> What I would like to do is to use ROOT as a graphical implement for my C
> programs. In the very simple case I would like to draw a simple vector
> which would move as its coordinates change during the execution of my
> program, in other words, I would like to watch the dynamics of the
> process. I know that it is possible with ROOT to draw different
> STATIC objects and I have tried to make a simple loop which would draw
> the same object with different coordinates on the canvas,
> but it did not work. Although the loop was executed without errors what I
> saw on the canvas was the object with the last coordinate set from the
> loop. The canvas did not draw the coordinates from the preceding steps.
>
> Could anyone suggest how to implement this sort of animation
> with ROOT?
>
> best regards
>
> Feodor Ogrin.