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

Hi, Sylvain-

Sylvain Galineau wrote (on 6/29/10 3:21 PM):
> (Copying Doug as I am not sure whether this is a concern of the FXTF
> or the SVG WG proper)

In general, if there is a question or issue that affects both CSS and 
SVG, it should be sent to the FXTF.  That way the participants of both 
groups know about it, and can deal with it in their own specs as well as 
any joint specs.


> 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.

Agreed.


> 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.

That sounds good to me.


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

Without knowing the background of the exclusions, my opinion is that the 
SVG WG should simply align to whatever CSS defines here (and I suspect 
the rest of the group will say the same).

I believe that these 'writing-mode' property may have come from XSL-FO 
originally... in any case, we should all align together (CCing Liam Quin).

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

Regards-
-Doug Schepers
W3C Team Contact, SVG and WebApps WGs

Received on Wednesday, 30 June 2010 10:13:56 UTC