Umlauts are corrupted on printing

[Markus87]

I noticed a curious problem on printing on a real printer from Windows.
If we print from our software umlauts they are corrupted starting with v7.210.
Also this problem only shows if printing with a physical printer, the pdf or xps printer do not show it.

They are okay with v7.200, so we just downgraded.
But maybe this is useful for you somehow.

[kalapi]

Hello @Markus87

Thanks for filing the issues. Unfortunately i'm not able to reproduce this on my end. I'm using the following:

Software/Hardware	Name/Version
Operating System	macOS 10.15.5
App	TextEdit
Font format	OTF & TTF
Weight(s)	Thin, ExtraLight, Light, and Regular
Printer	HP Laserjet P 1102w

If you can provide similar info, it would be easier to pinpoint the issue :)

[JulietaUla]

Thank you @[email protected] <[email protected]> :) El lun., 27 jul. 2020 a las 3:16, Kalapi Gajjar (<[email protected]>) escribió:

…

Hello @Markus87 <https://github.com/Markus87> Thanks for filing the issues. Unfortunately i'm not able to reproduce this on my end. I'm using the following: Software/Hardware Name/Version Operating System macOS 10.15.5 App TextEdit Font format OTF & TTF Weight(s) Thin, ExtraLight, Light, and Regular Printer HP Laserjet P 1102w If you can provide similar info, it would be easier to pinpoint the issue :) — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#108 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACXUQKQRVKPNGELYO3H7LN3R5ULURANCNFSM4PEX73LA> .

-- :) +54 911 5668 5843 Julieta Ulanovsky Buenos Aires

[Markus87]

Hi @kalapi

Thanks for the quick response and sorry for the little detail of the issue.
I was afraid that this will not be easy to reproduce. It happens out of our application we make, and we have custom print code, so its absolutely possible it is our fault. Maybe I can reproduce it with a program Windows provides.
I am currently on holidays, but I will try to provide you with better information when I am back at work.

[kalapi]

It could be on your end, but it also could be a regression in v7.210 especially because the previous version works and not much has changed in the text layout code in the relevant tables. However, my initial checks haven't produced any issues.

I'd love to get more info If/when you and back and have time.

Thanks again!

[moyogo]

This could be a buggy printer TrueType interperter, as some fail to handle glyphs with nested components (composite glyph using another composite glyph as a component).
The fontmake/ufo2ft flattenComponents filter is used in the UFO-source based Montserrat that was made for Google Fonts, see googlefonts@653c946.

[Markus87]

@kalapi I finally had time to investigate this issue again and I was able to create a small program which reproduces the issue we have in our application.
I also noticed the issue can only be reproduced if printing in landscape mode, switch to portrait and it works. 🤷‍♂️

Software/Hardware	Name/Version
Operating System	Windows 10 (Version 2004)
App	Custom Application(see attached example)
Font format	TTF
Weight(s)	Default (Regular?)
Printer	HP PageWide 377dw MFP

Example program:

• Example good prints with v7.200
• Example bad prints with v7.210
• The program will close itself after printing
  

Prints look like that:

Download source
Download application