Augmented Reality: virtual world not overlapping real world correctly

[Jeff]

In your code, two coordinate swaps are applied to the position data. One to the headtracker and one to the viewlink. Do all virtual movements (left,right,up,down) match the physical ones? If so, then that's probably fine but it should only be necessary to apply coordinate swaps once.

You may need to account for a unit conversion between Phasespace and Vizard but applying an additional scale factor should not be necessary. I would recommend testing with a simple script, just add an axes model linked to the head tracker and print out the data every frame. Verify that works properly on its own before incorporating the tracking data into this script. Is the Phasespace origin calibrated to the ground plane?

To account for the offset between the user's eyes and position tracker mounting, apply a preTrans operation to the viewlink. The values you are using indicate the position tracker is mounted in front of the user's eyes. Is that the case?

viewLink.preTrans([0,-0.08,-0.05])