[css3-text-layout][svg] writing-mode values across CSS and SVG

(Copying Doug as I am not sure whether this is a concern of the FXTF
or the SVG WG proper)

Currently, CSS3 Text Layout defines the writing-mode property as taking:

	lr-tb | rl-tb | tb-rl | bt-rl | tb-lr | bt-lr

In SVG1.1, Second Edition [2], writing-mode supports :

	lr-tb | rl-tb | tb-rl | lr | rl | tb | inherit

1) In addition to the inherit keyword, SVG adds shorthand values
for lr-tb (lr), rl-tb (rl) and tb-rl (tb). 

2) SVG also drops bt-rl, tb-lr and bt-lr. 

To make both authors and implementors lives easier - especially in mixed
documents - both WGs should harmonize the values this property supports.

At a minimum, I propose that the CSS3 definition of writing-mode:
	1. Include the inherit keyword
	2. Include the shorthand values defined by SVG i.e. lr, rl and tb.

I suspect SVG drops certain direction combinations due to the lack of 
known script for them but those may be useful for other purposes.


[1] http://dev.w3.org/csswg/css3-text-layout/#writing-mode
[2] http://dev.w3.org/SVG/profiles/1.1F2/publish/text.html#WritingModeProperty

Received on Tuesday, 29 June 2010 14:22:36 UTC