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WorldViz Peripherals
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analogDev = vrpn.addAnalog('PPT_WAND%d@%s:%d' % (markerid, hostname,
8945))
#create button device for the buttons
buttonDev = vrpn.addButton('PPT_WAND%d@%s:%d' % (markerid, hostname,
8945))
VRPN (GENERIC)
The Virtual-Reality Peripheral Network (VRPN) is the preferred method of connecting
to your host application. The Ethernet-based network connection is versatile and
offers lower latencies than serial communication, especially for large numbers of
markers and high update rates. If your host application does not currently support a
VRPN connection, adding this functionality is straightforward. Both VRPN6 and VRPN7
are supported.
Instructions:
1. Please make sure you have a calibrated PPT system and have the PPT Studio
running.
2. In PPT Studio settings, select the correct number of markers for tracking and
select the VRPN 7 plugin as the Output plugin in the Configuration panel.
3. If PPT Wand is used, please make sure you have both MarkerID and PPT Wand
plugins selected. For the MarkerID plugin, make sure the PPT wand is detected by
the PPT with the correct ID (default ID number 3 for single LED mode [power switch
DOWN]). For the PPT Wand plugin, please make sure the light number showing in
the Sensor Option window is corresponding to its marker ID number and is in
connected mode (if you can see the dynamically updated yaw, pitch, and roll data).
4. Press the TALK button (top left corner of the PPT Studio window) if it is not ON.
5. You should be able to access the PPT data through VRPN from your own
application by using the sample code below. In the following sample C++ code, you
can retrieve the position, orientation, button, and joystick data of a PPT Wand.
Similarly, you can just keep the tracking related functions if it is only for regular
marker tracking.
a. You'll need the VRPN library (header files) from this site.
http://www.cs.unc.edu/Research/vrpn/index.html