On Fri, 16 Sep 2005 07:10 pm, Luca Furini wrote:
> Manuel Mall wrote:
> > if we have a baseline-shift, eg.
> >
> > some X<fo:inline font-size="smaller"
> > baseline-shift="super">2</fo:inline> ...
> >
> > how is that intended to be modelled with respect to the
> > lead,height, and middle values to be stored in the created
> > KnuthInlineBoxes for the fo:inline?
>
> I think that more (or different) information needs to be stored in
> the KnuthInlineBoxes in order to fully implement the properties
> concerning the vertical positioning of objects.

I was afraid that would be the case.

>
> Lead, total and middle are only enough to handle vertical-align =
> top, bottom or middle; anyway, maybe three attributes could be
> enough: one identifying the alignment baseline (alphabetic,
> ideographic, text-before-edge, ...) and two specifying the box heigth
> above and below this baseline.

Not sure that would be enough. Its the baseline-shift that worries me. 
The system also has to cater for multiple levels of nested 
fo:inline/fo:character with changing baseline tables while exposing all 
this (in some form) up to the Line LM so it can calculate the proper 
line dimensions.

From my POV this needs quite a bit more thought and spec reading (this 
seems to become my pasttime now - don't read a good book - no, read the 
spec - again). Looks like we won't get sub/superscripts in a hurry as I 
want to tidy up other things first (still waiting for my apache 
account, so I can commit the changes accumulating here) before 
attacking this and trying to implement all the alignment stuff.

Would be really nice to get some wider variety of fonts to play with. 
May be including some unusual scripts with strange baselines. Do we 
need something like OFFO for fonts, i.e. a repository of open licensed 
but incompatible with Apache license fonts already converted for use 
with fop?

>
> The LineLM should look at these values when creating the lines: each
> box height will be interpreted differently according to its baseline:
> I think this will be the tricky part of this work!
>
> HTH, even if it' not much :-)

yeah, good one :-) I am still wondering what I let myself in for by 
joining this party.

>
> Regards
>      Luca
Regards

Manuel

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