Ruler in paint doesn’t normally work

What I did:
I’m trying to use ruller in my paint
I need the horizonltal line
I’ve set roller to 0 rotating it clockwise
And try to paint line

What happened:
The result line isn’t horizintal.
See screens



What I expected:

Things that might be helpful to know (Agenda version, OS and model, etc):

Please let us now about your device and OS version for it’s perfectly straight when I try that on my iPad Pro 12.9 2018 iPadOS 13.2. In full view as in preview.

Kind regards

Mick

iPadPro 11, iPadOS 13.1.2
It have several positions and all with 0 angle, especially if you rotate it clockwise

Hmm, it’s very odd. The ruler is entirely in the realm of Apple’s frameworks. We have no. control over that.

Does the line look horizontal in the drawing view? Ie is it just the inline version that looks odd? Is it just a question of a small image being blown up, so the antialiasing of the line causes a strange effect?

No, it’s not an antialiasing effect anв not a problem of small image, see the screen of large preview.