[css3-page] Variable dimension (was: Paged Media Level 3 - how stable is the margin boxes spec?)

Le 15/02/2012 03:13, fantasai a écrit :
> On 02/15/2012 12:54 AM, Mike Lawther wrote:
>> >  Hi guys,
>> >
>> >  I just wondering how stable the spec for Paged Media is (http://dev.w3.org/csswg/css3-page/).
>> >
>> >  In particular, is the margin box stuff likely to change? Is it stable enough to consider doing a (vendor prefixed) implementation?
> The names of the margin boxes is very stable: there are at least 4 implementations
> at this point, IIRC. The layout algorithm, less so. Simon Sapin had some comments
> on it, see
>     http://lists.w3.org/Archives/Public/www-style/2012Jan/0441.html

Hi,

We do have a released partial implementation:
http://weasyprint.org/#sample-output

I did not prefix the @-rules, I’m not sure if I should have... (As 
fantasai said, the names are unlikely to change.)

The biggest pain point was Margin Box Variable Dimension Computation 
Rules. The current spec is very hard to implement and no one implements 
it correctly AFAIK. I think it should be changed.

The implementation difficulty lies in 'auto' values for margins.
Changing to something like this would makes things much easier from an 
implementer point of view:

     If 'margin-*' computes to 'auto', its used value is is '0'.

 From an author point of view, it would mean that many interesting 
layouts with auto margins are not possible anymore. But are they really 
interesting?

Regards,
-- 
Simon Sapin

Received on Wednesday, 15 February 2012 14:22:43 UTC