Re: [Fenfire-dev] darcs patch

[Benja Fallenstein]

Hi Tuukka,

thanks for the patch! Applied (with some small twids, see fencommits).

Tuukka Hastrup wrote:
> I know these aren't implemented correctly, but they work for me in 
> FenFeed. Took me some 12 hours to get this far,

:-/

> so now please tell what I did wrong :-)

Actually, it's good except for ugliness of having the 
visibleFractionModel in ViewportLob, which is probably what you're 
referring to. Even that's a reasonable compromise if you shy away from 
introducting new lobs, though. ;-) The better solution would be--

> Particularily, getting Lob sizings as Models would be helpful.

--by using wrapper lobs that do that, like this:

    AssignedSizeGetterLob
             |
        ViewportLob
             |
   PreferredSizeGetterLob
             |
         (content)

(I have a hard time coming up with good names for these, any 
improvements appreciated!)

Each of these would have two float models, one for each axis. 
AssignedSizeGetterLob would, when setSize is called, write the size 
assignment into its models; PreferredSizeGetterLob would, when 
constructed and when chg() is called (which is how children notify 
parent lobs of changes in size request), request the child's preferred 
size and write it into its models.

These would extend AbstractMonoLob.

AssignedSizeGetterLob will also have an application in a redesign of 
Breaker I'm planning, which will move the linebreaking code into a 
SequenceModel. Then the current Breaker(textmodel) will look like this:

    AssignedSizeGetterLob(xmodel, ymodel, content =
        Box(Y, model =
            LinebreakingModel(model = textmodel, width = xmodel)
        )
    )

-- i.e., the linewidth, which is a parameter to LinebreakingModel, will 
be set by AssignedSizeGetterLob.

I'm too lazy to implements AssignedSGL and PreferredSGL now -- you can 
do it if you like, otherwise it stays ugly for now :-)

- Benja