WorldViz PPT-E, Руководство по эксплуатации, Страница: 57 / 163

Using 3D Data
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For cases in which the PPT wireless marker's actual altitude should be retained and
only the X and Z axes reset to zero, remove the viz.RESET_Y flag from the example
above.
Accessing the raw data
To access the raw data from the PPT marker (including orientation data if the marker
is running in 6DOF mode), use the following technique.
data = tracker.getData()
# Access the raw data
print data # Print the array of data
Applying Scale factors
To apply a scale (gain) factor on your position data, use the link's postScale method
to arbitrarily establish a non-identity scale along any of the three dimensions. In the
example below, the X and Z dimensions are given a 2.0 scale factor while the Y
(altitude) dimension is kept to the default of 1.0.
link.postScale([2,1,2],target=viz.LINK_POS_OP)
Connect to PPT using viztracker
This is the most convenient method if you do not need to perform transformations on
the tracking data and just want to use the tracker within a 3D world. To help you get
started with viztracker for PPT, you should install the latest Vizard release (at least
3.16). You should then write a file called vizsetupcfg.py with your tracker
configuration (included below). The main advantage of using viztracker is it abstracts
the tracking details so that changing your tracker configuration ideally has no impact
on your Vizard applications.
In your application, the viztracker module is called to configure the display and
trackers.
import viztracker
tracker = viztracker.go()