I’ve been toying around with setting up a grating experiment online and I’ve realised that PsychoJS seems to reflect angles about the vertical line, with respect to what one sees with the same experiment in psychopy. It does, of course, report the correct orientation.
If I display a bar with an orientation of -20 degrees, in psychopy this bar is tilted slightly counter-clockwise of vertical. In psychoJS this bar is tilted slightly clockwise of vertical, but is still logged as -20 degrees.
This issue has been previously reported here https://discourse.psychopy.org/t/orientation-of-an-imagestim-is-set-differently-in-local-and-online-versions/12902
For now I can work around this, but it would be good to get a fix!