Blurry marker sting produced by threex-arpatternfile.js (pr)

[XiaNi]

I want to add pull-request to fix blurry marker parts generated by threex-arpatternfile.js (will do it tomorrow if everything is ok with this change).

What is the current behavior?
i visualized marker string onto canvas and found that rotated versions are blurry.
here on screenshot first three small images are channels of unrotated marker image, and then goes rotated 90deg and it was blurry:

What is the expected behavior?

zoomed version:

[nicolocarpignoli]

you can open it, of course :D