Bug 130840

Summary:

Add Support for Glyph-level mirroring

Product:

WebKit

Reporter:

Frédéric Wang (:fredw) <fred.wang>

Component:

Text

Assignee:

Nobody <webkit-unassigned>

Status:

NEW ---

Severity:

Normal

CC:

cfleizach, mmaxfield, mrobinson

Priority:

Version:

528+ (Nightly build)

Hardware:

All

OS:

All

Bug Depends on:

Bug Blocks:

123018

Attachments:

Description	Flags
testcase	none

Description Frédéric Wang (:fredw) 2014-03-27 08:37:49 PDT

Created attachment 227948 [details]
testcase

Currently, Font::glyphDataForCharacter accepts a mirror boolean to apply Character-level mirroring. However it does not allow to apply Glyph-level mirroring. See

http://www.microsoft.com/typography/OTSPEC/TTOCHAP1.htm#ltrrtl

This is needed for MathML operators such as integrals or sums, that don't have character-level mirroring defined in Unicode. 

In Blink & Gecko with the XITS fonts installed, the attached testcase shows mirroring of the bracket (character-level) and sum (glyph-level). The latter relies on the 'rtlm' feature of the XITS. Note that for MathML purpose, all what is needed is a way for Font::glyphDataForCharacter to use the rtlm substitution table, not to implement the font-feature-settings CSS property.