CAVE tracking question

[NASA GRC]

I'm having some trouble getting cave tracking to work correctly. I've implemented it successfully on our one-wall system (using VRPN), but am having frustrations on our four-wall system. To solve my problems, I need a better understanding of whats going on in the example code in the vizard documentation.

This line:
cave.setTracker(pos=viewtracker)

should that be sufficient in linking the viewpoint to the tracker? By using this line alone in our fourwall system, there is an apparent linkage occuring, but the results are not accurate.

When I add this line:
caveorigin = vizcave.CaveView(viewtracker)

that solves some problems but introduces others.

Then the following lines:
origintracker = viztracker.KeyboardMouse6DOF()
originlink = viz.link (origintracker, caveorigin)

from the docs confuse me. Namely, why is the caveorigin being assigned the viewtracker at initialization, when its value is just being overwritten with the vizlink later? In fact, in my one-wall solution, I set the matrix of caveorigin explicitly as a result of lots of matrix math from the wand values. Why is the viewtracker value used with caveorigin to begin with?

So my two questions are:

1) should that first line of code alone be sufficient in setting the tracker to the viewpoint (hypothetically if moving the origin is not desired)?

2) why is viewtracker used to initialize caveorigin, when caveorigin is redefined later with vizlink.

These answers should help me find where my troubles are. Thanks.