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Grant [Tobii]

Hi @jespa007, glad you found the document useful. Let me try to address your points.

1. For example when I capture calibration gaze information through the function tobii_calibration_collect_data_2d, is enough calling one time or it has to be more times ?

tobii_calibration_collect_data_2d should be called once per coordinate you want to calibrate, so for a typical 5 point calibration sequence it should be called 5 times.

2. Another thing is, If I’ve calibrated 5 points I suppose that what tobii_calibration_point_data_receiver it returns is a pointer with a total size of
the size of tobii_calibration_point_data_t multiplied by the total of points calibrated (in my case 5) ?

tobii_calibration_point_data_receiver_t will be called once for each tobii_calibration_point_data_t that is contained in the “calibration blob” so the pointer is a pointer to a tobii_calibration_point_data_t

3. It seems that only gives one plot per calibrated point, and not gives and array of eyetracker calibrated points … but again. May be I misunderstood something.

Consumer trackers (4C, ET5) will only return an average point that is computed from all of the collected samples. Tobii Pro trackers returns each individual sample. So, with ET5 it will not be possible to reproduce the image in the document from the calibration results. The way to solve that is to show additional stimuli points and collect additional data after the calibration is completed and base the visualization (and calibration quality assessment) on that data instead. It has several advantages, most of all that it will represent actual eyetracking quality better than the calibration data.

Hopefully this clarifies the situation, please let us know if we can provide any further information. Best Wishes.