Bug 36114 – REGRESSION: Some Chinese fonts like MingLiU (新細明體) render incorrectly

• Component: Layout and Rendering
• Status: RESOLVED INVALID

Created attachment 50702 [details]
screenshot 

I'm using Safari 4.0.5 for Windows. (WebKit 531.22.7)

See the screenshot I attached.
I found that 2 Chinese fonts are rendered incorrectly, both of which are from Microsoft.

PMingLiU (新細明體 MingLiU.ttc)
DFKai-SB (標楷體 KaiU.ttf)

This bug never happens in Safari 4.0.4 or earlier.

<!-- HTML tested in the attached screenshot: -->
<p style="font-size: xx-large"><span style="font-family: 微軟正黑體;">微軟正黑體</span><br/>
<span style="font-family: 新細明體; color: red;">新細明體 12345abcde</span><br/>
<span style="font-family: 標楷體; color: red;">標楷體 12345abcde</span><br/>
<span style="font-family: Trebuchet MS;">Trebuchet MS</span><br/>
<span style="font-family: 華康新儷粗黑;">華康新儷粗黑 12345abcde</span><br/>
<span style="font-family: 華康儷粗黑;">華康儷粗黑 12345abcde</span></p>

Currently I have a not-so-good workaround:
Set the Font Smoothing in the Preferences to "Windows standard".

[Alexey Proskuryakov]

<rdar://problem/7754643>

This probably needs to be addressed in Apple’s Core Graphics library.

Um... What should I do for now?

[Simon Fraser (smfr)]

Explorer: please attach the test file you're using to generate the screenshot. It would also be useful to see a screenshot with the correct and incorrect rendering side by side.

Created attachment 51204 [details]
testcase2

Created attachment 51205 [details]
comparison screenshot

I'm too lazy to reinstall the old version, so I attached the screenshot with font smoothing on (above) and with font smoothing off (below).

[Simon Fraser (smfr)]

Could you be more precise about the "render incorrectly"? Does the "comparison screenshot" show the difference between "bad" and "good" rendering, or does only the original screenshot show the "bad" rendering?

Yes, in my "comparison screenshot", the window above shows the bad rendering, and the window below shows the good rendering.

Also, it seems that the bug only affects CJK Ideographs.

I've now downgraded to Safari 4.0.4, but I cannot see it work again.

Created attachment 51917 [details]
screenshot with newer font version

I've done another experiment.

After manually upgrading my system fonts, I found that MingLiU and PMingLiU works for font version 6.02 (the version included in Windows Vista).

However, DFKai-SB still fails with the latest font version. (5.00 , also included in Windows Vista)

Created attachment 52492 [details]
font file (DFKai-SB)

(In reply to comment #3)
> This probably needs to be addressed in Apple’s Core Graphics library.

Further investigation confirmed that this is a regression in the version of Core Graphics that shipped with Safari 4.0.5. Addressing it is outside the scope of WebKit, so I am closing this report. As mentioned above, the issue is tracked by Apple as <rdar://problem/7754643>.

Thanks for filing the report!

This is fixed in Safari 5.