Problem with broken contour

Hello everybody,
I have a little problem and I don’t know, what to do with it. In Glyphs contour looks ok,

but in Figma contour looks like this.

Does anybody can help me ?

I recommend that you put an anchor point right where the curve changes, this goes against the orthogonality criterion, but it is an exception

  1. Export with CFF curves rather than TT curves.
  2. Keep number of points low
  3. Understand interpolation kinks, see Avoiding Kinks in this tutorial:
  4. Avoid short handles and small segments. Grid rounding will cause kinks.

I have a similiar issue with a font, but the app is not Figma it is a custom app. (The client has build his own software for a machine to produce signage. ) Some letters gets twisted contours while exporting to an pdf. I do not know what causes this. Never seen this before. It does not appear in other apps. I do not think this is an issue with other fonts that they use. They are on a windows environment. Any suggestions?
(PS. For some reason they uses Font Forge on the fonts. I have no idea why.)

Could be an outline direction or hinting issue. You can verify the font with OTMaster.

Since it is Windows, it may be a format issue. Most Windows software is not capable of properly processing CFFs (.otf). Try giving them an unhinted TTF and see if that improves results.

PDF Generation on Windows is a dodgy business. Most of the PDF generators on Windows are buggy. Do you know which rendering engine they are using, and which PDF generator they implemented in their software?

Some rendering engines have a problem when he starting point is an off curve point.

I will ask them which rendering engine they use and send them different versions of ttf, which is the format that they use. I get back.

They use wkhtmltopdf. Any suggestions?

I don’t know that one. Is there support from the people who make wkhtmltopdf? It might be a known problem.

Have you tried resetting the start point?

It doesn’t really matter what software is generating the pdf (as long as it isn’t decomposing the outlines).

What app is used to show/rasterise the pdf? Does it look broken in all of them (e.g. try in Apple Preview).