I've played with a few PDF libraries and font rendering in general could be a lot better.
There is not such thing as not supported font, maybe you used other format than ttf or otf, in any case probably your problem in rendering it's the library's fault, not the font (trying to keep the answer short, I don't want to bore you with typography and fonts 😅).
I have a huge gap in my knowledge when it comes to that kind of things :/
I thought, and apparently I'm wrong, that because I used a Linux server, the font I was using needed to be supported by all OS to make sure the rendering would not differ.
Now, I'm only referencing fonts from the CSS, with a good old font-family property.
I don't know if I'm clear, nor if my approach is right (it's probably not). But don't be afraid to bore me, I would love to learn more :D
Your approach is perfectly fine. I wanted to relieve you about the rendering bug, it's not your fault.
Helvetica is probably one of the most widely used font families (Arial is Microsoft helvetica version, but that's another story).
You're doing great taking into consideration the limitations here.
You've discovered that working with fonts is harder than you thought and that's okey!
That's reassuring. I guess I'll postpone thinking about this when I would need to add support for different fonts
This post from Coding Horror may be of help.
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