PDFsharp & MigraDoc Foundation

Hi folks!

I've been using PDFSharp in one of my apps but I've noticed that if we've got emojis in a text string they're not outputting correctly - I just get a rectangular shape instead.

Can I check if this is a known limitation or if there's anything I need to look out for when outputting such content?

Thanks all and apologies if this is a newbie question

Mike

This is a limitation of the current implementation.

Code that supports surrogate pairs can be found via this page:
https://github.com/empira/PDFsharp-1.5/issues/63

_________________
Best regards
Thomas
(Freelance Software Developer with several years of MigraDoc/PDFsharp experience)

I have done research on this for a couple days and have only found that PdfSharp/MigraDoc just do not support surrogate pairs.

I hear that there is a pull request with a fix for this, but I can't find the code anywhere.

Has anyone been able to make this work?

the link doesn't resolve. Is this code available anywhere?

The link works.

_________________
Best regards
Thomas
(Freelance Software Developer with several years of MigraDoc/PDFsharp experience)

Code that supports surrogate pairs can be found via this page:
https://github.com/empira/PDFsharp-1.5/issues/63

_________________
Best regards
Thomas
(Freelance Software Developer with several years of MigraDoc/PDFsharp experience)

Perfect, that was precisely what I needed! Thanks!

I had to apply all the code changes that @TheRealSourceSeeker suggested but in the end it works great. Now if I could only get color emojis to work.

I recently got colored emojis working in the current 6.0 version by supporting color-tables stored in font-files.
I took the code from the mentioned issue and expanded from there.
See this commit (and this for a small optimization)

Note there are 2 Versions of color-tables (Version 0 and Version 1).
https://learn.microsoft.com/en-us/typog ... /spec/colr

Version 0 basically supports only "flat" colors per layer.
Version 1 is more advanced, supporting gradients and such.
The code in the commit ONLY supports version 0 tables

I have to admit i'm absolutely NOT an expert regarding encodings, font-handling and what have you; so be aware the code may contain flaws that are not obvious to me.

That said, i testet this successfully with the Segoe UI Emoji font, which has a version 0 color table.
I also added a test-case to render all characters supported by a certain font.
All characters of the mentioned Emoji font showed up correctly (as far as i can tell).

I'm not 100% certain, but it should not be too hard to port this to 1.5, if you need it there.