TRACKPixx support

@Kohitij: As of the current nightly build, I think MWorks’ support for the TRACKPixx3 is in pretty good shape.

VPixx recently released version 3.12 of their software tools, which you should install on any Mac you want to use with the TRACKPixx. In addition to providing the latest API, this release also fixes the issue with vpixxdeviceserver slowing itself down by generating huge log files, as well as the issue that caused device initialization to fail when setting the expected iris size.

The latest VPixx tools also add support for setting the tracking mode to “headfixed NHP”. According to the release notes, doing so “will greatly improve the tracking for head fixed subjects”. However, the notes also say that this feature requires DATAPixx3 firmware version 24 . When I tried installing this firmware, I found that the DP3 could no longer drive the display I had connected to it. Reverting to firmware version 22 resolved the issue. This might be an issue with the specific display I was using, so maybe you’ll have better results, but I thought you should know.

Also, while MWorks does support the TRACKPixx’s built-in calibration routines (see this example experiment for a demonstration), they seem to be a little flaky. Specifically, immediately after performing a gaze calibration, MWorks reports a bunch of errors saying “TRACKPixx returned out-of-bounds schedule frame buffer write address”, which suggests that a buffer on the DATAPixx has gotten corrupted somehow. However, the eye data that MWorks does receive still seems valid, and if I close and reopen the experiment and load the saved calibration from the TRACKPixx, everything works fine. Also, the TRACKPixx pupil-size calibration doesn’t seem to work at all. All that said, if you’re going to let MWorks calibrate the eye data (i.e. by feeding the TRACKPixx’s raw eye positions in to a linear eye calibrator), then these issues shouldn’t affect you.

I think that covers it. If you have any questions or run in to any issues, please let me know!