1204903 - [PDF Viewer] Incorrect OS/2 font rendering (error: bad cap_height)

Status: RESOLVED FIXED

(Firefox :: PDF Viewer, defect, P2)

Description

[niklas]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:40.0) Gecko/20100101 Firefox/40.0
Build ID: 20150826023504

Steps to reproduce:

This bug introduces itself when generating a PDF with [TCPDF](http://www.tcpdf.org) and using [Google's Roboto font](https://github.com/google/roboto/tree/558379729452a4409bc632bddd60e5b7f1fdba41) as the PDF font. Both Safari and Chrome shows these PDF:s just fine using their own engines.

I am atttaching a screen shot comparing Safari 8.0.8 and Firefox 40.0.3. I am also attaching a compressed archive containing a testcase. Drop the testcase into your web server and visit the URL with Firefox.


Actual results:

Ugly/incorrect characters show.


Expected results:

Four english sentences should be visible in the PDF.

Comment 1

[niklas]

Attachment: Safari vs Firefox PDF rendering (Screen Shot 2015-09-15 at 16.41.49.png)

Comment 2

[niklas]

Attachment: PHP test case for creating the incorrectly rendered text

I tried attaching a complete zipped archive of the fonts, tcpdf, and the php script, but it hit the file size ceiling. You will have to assemble it again, sorry.

Comment 3

[Loic]

We don't need the php script to generate the PDF, but we need the resulting PDF. Please, attach the PDF file to the bug report.

Comment 4

[niklas]

Attachment: Generated PDF

Comment 5

[Loic]

Console (FF40):
PDF fee49ca4650e4d3496ca1f62806496f9 [1.4 TCPDF 6.2.12 (http://www.tcpdf.org) / -] (PDF.js: 1.1.114) viewer.js:6397:1
downloadable font: OS/2: bad cap_height: -21 (font-family: "g_font_4" style:normal weight:normal stretch:normal src index:0) source: data:font/opentype;base64,T1RUTwAJAIAAAwAQQ0ZG(...)
downloadable font: OS/2: bad cap_height: -40 (font-family: "g_font_6" style:normal weight:normal stretch:normal src index:0) source: data:font/opentype;base64,T1RUTwAJAIAAAwAQQ0ZGI(...)

No error message in FF43, the rendering is better but still broken.

Comment 6

[Loic]

Attachment: ff25-screenshot.png

In the past, the rendering was almost normal, only bold/italics were missing, see my screenshot.

Reg range:
http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=5ceea82a79c7&tochange=a4c1961bf723
Ryan VanderMeulen — Bug 897554 - Update pdf.js to version 0.8.377. r=bdahl

Comment 7

[niklas]

I just want to drop by and say that 41.0.1 did include some improvements, the characters all render as they should but tracking (or kerning) is way off.

Comment 8

[niklas]

Updated to version 45 today and can indeed confirm that the issue has been fixed. Thanks!