Strange Behavior With Chinese Fonts

[Dr-NULL]

Bug Report

Description of the problem

PDFKit has a strange behavior when uses a chinese font, and use certain chinese characters.

Details:

• When inserts the first string ("冷冻去骨牛肉 / Frozen Boneless Beef / Carne Bovina sin Hueso Congelada"), this displays fine.
• But when inserts some characters (like "产品名"), the texts which inserted next only shows a few characters.
• Some normal characters such two-dots ":" doesn't rendered by PDFKit.

Code sample

I made a project with a extensive documentation of the problem:
https://github.com/Dr-NULL/Issues-PDFKit

Your environment

• pdfkit version: 0.10.0
• Node version: 10.16.3
• Operating System: Windows 10 x64 bits

[dasoncheng]

dcto.font(join(__dirname, "somewhere/fonts/苹方黑体-准-简.ttf"));

May be your font load error or do not support Chinese, i tried and it worked

see Dr-NULL/Issues-PDFKit#1

[Dr-NULL]

I was testing some fonts, specifically with Google Fonts (.OTF) and two open source fonts (Ping Fang and Founder Type Hei Ti). My observations are as follows:

• PDFKit has problems with OTF files.
• PDFKit normally works with TTF fonts.

I made some changes to the Issues-PDFKit repository. I added more fonts in the "./source" folder and added them to the "./src/global.ts" file. To test the other sources you just need to change the property called on line 14 of the "index.ts" file to another one inside the Global.Path.Fonts module.

Finally, I attach a preview of how PDFKit renders some of the fonts tested in the attached screenshots:

Font NotoSansSC OTF:

Font NotoSerifSC OTF:

Font PingFang TTF:

Font FZHei TTF:

[Dr-NULL]

Finally that report give me some doubts:

• ¿Really PDFKit has OTF files support and definitedly this is a bug?¿Or PDFKit hasn't ificial OTF files support?
• In the case if OTF files aren't officially supported, ¿Do you have contemplated add OTF files full support?

[blikblum]

Some OTF bugs were fixed recently.

Please create a self contained example, with font using https://repl.it/@blikblum/minimal-pdfkit so we can look at it

[Dr-NULL]

The problem still occurs with OTF fonts. The example code is HERE. When you run the project, that create 2 PDF files. One file is created with a OTF Font (fails), and the another PDF is created with a TTF Font (working).

[blikblum]

I confirm a bug exists but is not necessarily related with OTF format.

I tested with PingFang otf and ttf formats and both works fine

Testing with noto sans otf shows the bug. I could not find a noto sans ttf version and the online converters do not properly work with this font.

[v-python]

Some Chinese fonts apparently use obscure features. Someone sent me a Chinese TTF font that most font web sites can't successfully manipulate. And some browsers can't display it correctly, seems there are some special flags that some tools & browsers don't handle properly, but that are the basis for sharing strokes among glyphs which can make a Chinese font significantly smaller.

[blikblum]

This specific font works in other web tools.
I already identified a bug in fontkit, looking into it

[blikblum]

Fixed a bug that affect noto sans otf font at foliojs/fontkit#207. Hopefully will fix this.

[Dr-NULL]

Thanks for all @blikblum , but I can't access to the last changes applied into the lib. I assume that I'll waiting for test these changes to the master branch when the push request will done.

[Dr-NULL]

The problem continues, I tried with updating PDFKit, the last version that NPM downloads is 0.10.0 and this is the result with NotoSansSC.otf:

...and with PingFang.ttf:

The most strange part is if I try to print the pdf with OTF broken font using SumatraPDF (by console), returns the following error:

[blikblum]

The fix is not released yet