Using ioTracker through VRPN and OpenTracker, applications
for previous magnetic tracking are updated to make use of new optical tracking equipement available
on the VizWall. Interaction methods are updated to work with the new equipment
Optical tracking is a method to register the spatial location and
orientation of a marker relative to a coordinate system based on the location of the cameras that do the tracking.
Tracking is accomplished by sending out infared flashes, which are then reflected of specific areas on the markers.
The reflection is picked up by cameras, and based on triangulation the location of the marker can be determined.
Tracking and volume rendering
Volumeshop had several plugins which allowed for tracked interaction
with a volume rendering. The magnetic tracking system allowed for movement, as well as interaction with a mouse pointer.
With the optical tracking system a similar response to movement was used, but since no mouse clicking is available on the optical
system, a marker is used for mouse interaction. The current approach uses one marker for movement and one to directly control the
orientation of the volume visualized. Other interaction techniques were explored, but this was decided to be the most intuitive interaction scheme.
Open the "Optical Tracking" folder on the desktop of the vizwall computer and launch Volumeshop.
Proceed to open the OpticalTrackingExample.xml with Volumeshop. Markers 6001 and 6005 are currently in use. For good results
keep all reflective parts of the markers visible to all cameras. To test the Hello world application, open "Optical Tracking"
on the desktop of the VizWall computer and launch "Hello World".