[css3 writing modes] text orientation and vrt2/vert

Since the algorithm for the proposed 'text-orientation' property relies
on the use of the 'vrt2'/'vert' features, I've put together a simple
testpage that tests the use of the OpenType 'vrt2' and 'vert' features
in commonly available Japanese fonts, Hiragino Mincho (OSX), Meiryo
(Windows) and Kozuka Mincho (Adobe). The range of codepoints listed is
the union of the cmaps from all three fonts:


This testpage requires the use of Firefox 4 or higher, since it uses the
'-moz-font-feature-settings' vendor-specific property to enable specific
OpenType features.  Under Internet Explorer and Webkit Nightly, it uses
a vertical writing mode, so the testpage illustrates the orientation
mapping table (i.e. upright or rotated) used by those apps instead of
the OpenType features.

A few simple observations:

- Greek/Cyrillic don't rotate when 'vrt2' is enabled but Latin does
- Meiryo is very inconsistent, some extended Latin codepoints are not
  included (i.e. they remain upright while other Latin codepoints rotate)
- some ranges are consistent across these fonts but inconsistent with
  other codepoints, e.g. pre-formed fractions U+2153:215e for which half
  the codepoints rotate, half remain upright
- arrows seem to rotate but only when left/right/up/down (e.g. U+2190:2199)
- math symbols rotate (Meiryo inconsistent)
- currency symbols rotate, units do not
- full-width characters remain upright but vertical alternates exist for
  things like brackets
- half-width katakana rotates
- Both IE9 and Webkit Nightly do wacky things with non-BMP ideographic
  characters, IE9 rotates them, Webkit Nightly doesn't display them at all (!!!)

Received on Sunday, 24 July 2011 07:13:26 UTC