GNOME Bugzilla – Bug 99523
Add support for additional writing directions (vertical)
Last modified: 2007-05-24 20:16:32 UTC
Pango needs support for additional writing directions. In the initial version of Pango, support is only present for right-to-left and left-to-right text. However, vertical writing is also important in many applications. One reason why vertical text has not been implemented in Pango-1.0 is that the target rendering system, X, has week facilities for handling text in other than a horizontal location. The obvious, though not the only, way of treating vertical writing is to keep the logic in PangoLayout the same, but to have an implicit transformation of the coordinate system. Doing it this way, the only extra code in Pango that is needed is to transform glyph metrics as appropriate. (some characters will rotate, some not), and also to handle selecting appropriate glyph variants when a font has separate variants for vertical and horizontal text. (CJK punctuation being a common example of this.) [ From TODO.xml ]
Situation is a better now for the target rendering system ... with Pango-1.8 we have pretty comprehensive support for rotated coordinate systems for all non-obsolete backends.
*** Bug 311982 has been marked as a duplicate of this bug. ***
Unicode Technical Note #22, Robust Vertical Text Layout: http://www.unicode.org/notes/tn22/
Created new bug 323172, bug 323173 and bug 323174 to split this into separate sub-tasks
Closing this one as it's been split into three, and the basic support has already been committed.
Remaining bits here are: - gravity and gravity_hint attributes and markup - more documentation - handling vert features in basic module Reopening to get these done.
attributes and markup are done. Remains to fill in the "Vertical Text" section of documentation with some text and samples, and to handle vert features in basic module.
'vert' was already fixed. 2007-05-24 Behdad Esfahbod <behdad@gnome.org> * docs/tmpl/vertical.sgml: Document how Pango's vertical text support works.