Help for a beginner!!

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Keerthan (kpv8370++at++usl.edu)
Sun, 06 Apr 1997 18:00:45 -0500

Please excuse me if this question is too trivial!! I think that the
origin in a Performer window is at the center and the view point lies
there. If this is correct, then the object in the simple.C
(pguide/libpf/C++)program should lie at the center once loaded.In order
to view the object, I use

        pfCoord view;
        view.xyz.set(0.0f,0.0f,15.0f);
        view.hpr.set(0.0f,-90.0f,0.0f);
        chan->setView(view.hpr,view.xyz);
         
I am setting my camera 15 units along z-axis and rotating the pitch 90
degrees in clockwise direction so that the camera will look downwards.Is
my assumption right?If so why am I not able to see the object?Has it got
anything to do with the bsphere.radius stuff.If so why?

Also ,could someone explain what the following segment does, especially
how the new position is computed?

while (t < 20.0f)
    {
        pfCoord view;
        float s, c;

        // Go to sleep until next frame time.
        pfSync();

        // Initiate cull/draw for this frame.
        pfFrame();
        t=pfGetTime();

        // Compute new view position.
        pfSinCos(45.0f*t, &s, &c);
        view.xyz.set(2.0f*bsphere.radius*s,
                     -2.0f* bsphere.radius*c ,
                     0.5f *bsphere.radius);
        view.hpr.set(45.0f*t, -10.0f, 0.0f);
        chan->setView(view.xyz, view.hpr);

        pfFrame();
  // }

I dont know if performer has got any coordinate system like openGL(where
you set using glOrtho)

Thanks,
Kiran
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