941629 - inaccurate full-justification of lines with automatic hyphens combined with CSS letter-spacing

Status: RESOLVED FIXED

(Core :: Layout: Text and Fonts, defect)

Description

[Jonathan Kew [:jfkthame]]

Attachment: screenshot of testcase rendering in Nightly on OS X

See testcase in the URL. Screenshot of rendering on OS X is attached.

Expected: all the line-final hyphens should align vertically, and should match the line ends non-hyphenated lines.

Actual: the automatic hyphens on lines 1, 3 and 4 project further than the explicit hyphen from "overly-narrow" on line 2, and the unhyphenated text on line 5.

Comment 1

[Jonathan Kew [:jfkthame]]

Attachment: take account of letter-spacing when adding the width of an automatic hyphen to the natural width of a justified line

This happens because PropertyProvider::SetupJustificationSpacing() fails to take account of any letter-spacing that should be in effect when adding the hyphen width. With this patch, the hyphens in the testcase all line up nicely.

Comment 2

[Jonathan Kew [:jfkthame]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/da7cc88ee78e

Comment 3

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/da7cc88ee78e