[HarfBuzz] Wrong offset returned by HarfBuzzShaper::offsetForPosition in some cases

• Component: Platform
• Status: RESOLVED FIXED

[Carlos Garcia Campos]

This bug has been revealed after enabling complex text by default in GTK and WPE ports in r221909.

[Carlos Garcia Campos]

Created attachment 320647 [details]
Patch

It doesn't fix all the failures after r221909, but many of them and produces results similar to the mac ones in others. I still need to investigate the weird space issues.

[Michael Catanzaro]

Comment on attachment 320647 [details]
Patch

r=me because this is the path to a better future, but this exacerbates our complex text selection rendering glitch, bug #148220. You can see that some of the expected results are now worse than before. E.g. editing/selection/select-across-readonly-input-4 shows the issue clearly.

[Michael Catanzaro]

(In reply to Michael Catanzaro from comment #2)
> Comment on attachment 320647 [details]
> Patch
> 
> r=me because this is the path to a better future, but this exacerbates our
> complex text selection rendering glitch, bug #148220.

To be clear, I mean r221909 has exacerbated bug #148220. Not this patch. I assume this patch is fine, but I don't know because I don't understand it. I'm just approving it because we have no font reviewers.

[Carlos Garcia Campos]

Committed r221974: <http://trac.webkit.org/changeset/221974>

[Myles C. Maxfield]

At some point we should do https://bugs.webkit.org/show_bug.cgi?id=167566.

[Michael Catanzaro]

(In reply to Myles C. Maxfield from comment #5)
> At some point we should do https://bugs.webkit.org/show_bug.cgi?id=167566.

I'd be excited to share as much code as possible, but I fear we don't have anyone who can help with this. :/

[Radar WebKit Bug Importer]

<rdar://problem/34694467>