[tei-council] how about this one?

[Conal Tuohy]

Hi Arianna

Just one point I wanted to pick up on from your email:

On Wed, 2007-08-15 at 17:32 +0100, Arianna Ciula wrote:
> Things get 
> complex though, because I think <zone> would have to allow nesting.

I don't think this is true ... see below

> To give a concrete example, since I would argue that, depending on the 
> interests of the encoder, the opening of a book could be considered a 
> <surface> where the wrapper <zone> could contain the <graphic> for the 
> opening and two further <zone>s children (the two pages contained in 
> it), we could have:

So this is a "double-page spread", right?

I agree that it should be possible to treat this as either 2 surfaces,
or as a single surface (with a crease down the middle ;-)

In your example, you've used nested zones, like so:

<facsimile>
<surface xml:id="opening157-158">
   <zone xml:id="op157-158" box="...">
     <graphic url="op157-158.png"/>
     <zone xml:id="157v" box="...">
      <graphic url="157v.png"/>
     </zone>
     <zone xml:id="158r" box="...">
       <graphic url="158r.png"/>
     </zone>
   </zone>
</surface>
</facsimile>

However, I don't think it's necessary to use nested zones to do this,
since presumably the areas defined by the @box attributes of the nested
zones "157v" and "158r" will fall within the area defined by the @box
attribute of the outer zone "op157-158". So the fact that the inner
zones are graphically part of the outer zone is already expressed using
the @box attributes and doesn't need to be redundantly expressed in the
nesting of XML elements. 

I can see that nesting makes things more complicated for encoders, and
even introduces the possibility of a difference between the inter-zone
relationships expressed by the nesting, and those expressed by the @box
attributes. For instance: it may be that the outer zone (containing a
"double-page" graphic) has been cropped tightly to show only the 2
pages, whereas the 2 inner zones (containing graphics of each page
individually) might have substantial margins in which you can see a
strip of the bed of a book-scanner. In such a case, these zone/zone/@box
attributes might not fall entirely within the @box of their parent zone.
In such a case, would you encode the single-page zones inside the
double-page zone, or not? I don't think it's even helpful to pose this
conundrum, so I'd recommend a single, flat, list of zones, without
nesting.

Cheers

Con