BF: should not fix units="pix" when drawing TargetStim during calibration

[mh105]

This was hell of a bug to hunt down...

The problem is as the following: when using the EyeTracker Calibration/Validation components in Builder, the GUI allows setting of Outer radius and Inner radius, and the Spatial units is grayed out as following the screen unit in the experiment settings. This is great and parsimonious design. But after some convoluted layers of overloaded dict() calls, we get to this part of psychopy.iohub.devices.eyetracker.calibration.procedure.BaseCalibrationProcedure. And it assumes the target_attributes to contain outer_diameter and inner_diameter in pixels.

This causes the strange behavior that the validation component works (because it correctly uses unit_type) while the calibration component fails to display any targets, giving the appearance of screen freezing. It is actually because the default value for these components under height unit setting for screen is 0.01. Since it's less than one pixel, nothing got displayed.

Fortunately the fix is simple because the unit_type got carried all the way into this function call, and we just need to set units=unit_type when using layout.Size(). Then everything works nicely and the calibration screen gets displayed.

[mh105]

Ah, looks like this was fixed by d62efd5 already, and we had the exact same fix :) Nevertheless, I think the ENH commit above is worth merging, since there's no need to keep the confusing Pix variables around when everything can be organized cleanly as arguments for the visual.TargetStim() constructor.

[TEParsons]

I think that code was added initially as a fix for Tobii eyetrackers, they use their own proprietary calibration code which needs to be in pixels. I'll test this branch with a Tobii next time I've got one to hand (we have one in the office), it may well be unnecessary following yours and @KirstenWilliams's other fixes but want to confirm before pulling in

[mh105]

It is possible that the layout.Size and getattr() call to get the radius and innerRadius variables are still necessary. Closing this PR since the core fix of using unit_type is incorporated in release 2024.1.5.