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Rotation direction inconsistency

URL of experiment: https://run.pavlovia.org/hsogo/muller_lyer/html/

Description of the problem:
I used Line Components to draw Müller-Lyer figure in this demo experiment and noticed that behavior of “Orientation $” parameter is different between local (i.e. python) experiment and online experiment. In local experiment, positive orientation results in clockwise rotation. On the other hand, in online experiment, positive orientation results in counter-clockwise rotation. I had to use Code Component to deal with this inconsistency.

Is this rotation direction inconsistency intended behavior? Or, is it a bug? I’m planning to write a document of how to build Pavlovia experiment and want to know whether this behavior will be modified in the near future or not.

Hi there Hiroyuki. Thanks for letting us know. That’s likely to be a bug.

For PsychoPy I chose to go with the “clock” standard rather than the engineering standard of polar coordinates. This is actually one break with convention that I probably regret, but I suspect the difference with PsychoJS is that it has reverted to traditional counter-clockwise orientations

@apitiot could you check/amend it? Thanks

Thank you for your reply. Maybe counter-clockwise rotation would have some advantages, but I have no problem with clockwise rotation :wink: