Area tree formats

When implementing the FOP extension I just woke up to the different area
tree formats delivered by FO processors

 

AHF structure

-----------------

<AreaRoot is-first="true" is-last="true" version="601.0"
xmlns="http://www.antennahouse.com/names/XSL/AreaTree">

<!-- . -->

</AreaRoot>

 

FOP structure

-----------------

<areaTree version="2.0">

<!-- . -->

</areaTree>

 

If you want to manipulate the area tree, you need to implement one and the
same functionality for each FO processor.

Of course you can implement some functions like "block-by-id" in
ppl-extensions.xslt, but manipulating an area tree in common way can't be
handled here.

 

As I don't want to implement functions twice, if it isn't necessary,
area-tree function should deliver a "standard" area tree, which is
transformed by the extension directly. And if so, there should be a
function, which transforms it back to processor's tree format.

 

area-tree($fo-tree) returns ppl tree format from FO tree by transforming
processor's tree with processor dependent XSLT

area-tree($ppltree) returns processor's tree format from ppl tree by
transforming ppl tree with processor dependent XSLT

area-tree-native($fo-tree) returns processor's tree format from FO tree
(that's what we have now)

 

Are there any thoughts?

 

Markus Wiedenmaier