Re: New Year. Renewed activity? New Chair?

Speaking as a hardcore software developer (I do have usage interests in 
FO, primarily in the ECM publishing/rendition space, say ECM + DITA XML 
+ FO engine) this would be interesting to spec out, and a fun challenge 
to work on.

Fact is, with a spec to drive appropriate XSL-FO APIs for 
notifications/events from rendering/layout, and also for R/T 
programmatic access to fixed & optional statistics for the object trees, 
you could then contemplate a feasible and practical set of layout engine 
runtime instructions, including things like Patrick mentioned or alluded "give me a complete dump of the layout for page 133 and why 
you the engine did that". Or "let's keep an eye on this condition loaded 
up by this rules file", which is a scenario inspired by what several 
people said.

My gut feeling is that more of the work associated with this is 
specification and API design - fact is, if an FO engine has been 
well-designed and implemented then much of this is reporting what 
already exists.


On 02/08/2013 04:04 AM, Dave Pawson wrote:
> On 7 February 2013 22:01, David Carlisle <> wrote:
>> On 07/02/2013 20:48, G. Ken Holman wrote:
>>> Or, you say declaratively, "this chunk of text is to be rendered
>>> within the following dimensions" (which isn't (yet) in XSL-FO).  Why
>>> does the creator of the XSL-FO have to be worried about the possible
>>> ways this is done?  If there are multiple ways this could be done,
>>> then parameterize the ways as properties of the intention to keep
>>> the text within the dimensions.  Then the renderer knows all of the
>>> characteristics of the author's intent with the block of text.  One
>>> of those properties would give the formatter constraints to play
>>> with the font size.
>> FO only gives so many fixed (parametrised) layouts I don't think you
>> can say (which is I think What Patrick says in (lua)tex). Here is a
>> database dump of hundreds of text fragments, arrange them in a suitable
>> order to avoid bad page breaks and typeset the result. Obviously if you
>> are typesetting a text book, that isn't the kind of layout requiremt you
>> want, but it's not exactly uncommon either.
>>> Perhaps your ideas could be incorporated in a new processing model,
>> well of course it's an old model, I think the lack of feedback from the
>> renderer is the main issue anyone coming from TeX or or a TeX-like
>> system faces when looking at XSL-FO.
> IMHO the prime request is for this feature,  yet it was hardly
> discussed in the WG.
> Given an 'if' or a 'choose' element in the vocabulary,
> what conditions would you want to test, using feedback from the layout engine?
> e.g. if 'pagebreak-due' to test if the next block would require to be broken.
> What conditions would you like to test?
> DaveP

Received on Friday, 8 February 2013 09:02:28 UTC