Re: [Tm4j-developers] Graph presentation

[Murray A. <m.a...@op...>]

Kal Ahmed wrote:
[...]
>> I have a preliminary XTM-to-TouchGraph converter working, though it is
>> missing a good deal of the topic map (such as occurrences and any sort
>> of interactive features). As a display tool for topics, associations,
>> and *some* of the scopes it works passably. But for now I won't be
>> spending so much time on it as my Ph.D duties are calling louder. But
>> perhaps working together on a Java API for XTM-in-TG I'd be happy to
>> lend a hand
> 
> That sounds cool. I think that there are two independent things which we 
> could collaborate on here - one is a common visualisation for XTM in TG 
> (e.g. what should be displayed as TG nodes and what should be TG arcs, 
> conventions on the use of colour, shapes and labels) such that two 
> different apps displaying XTM in TG could do so in a consistent manner. 
> The second would be a generic topic map viewer using TG (possibly built 
> on top of TMAPI). The third thing might be if I can just pick your 
> brains if I get stuck on the TG coding... ;-)

Gad, I hope you don't have to pick my brains. I was thinking it'd be
the other way around. Sometime this spring I hope to be able to release
my Ceryle application, which should provide a framework upon which some
of this can be built. It has a working implementation of Xindice plus
XNode (the API I wrote for putting metadata-laden XML into Xindice that
will hopefully make it into the Apache submission), plus a working
of TG that will (hopefully) have some sort of import and export to and
from GXL and XTM, though currently I'm not at all happy with it.

[...]
>> I instead decided to look at how GXL could be used for this purpose,
>> and that's when the light bulb went off -- it was an obvious choice for
>> a common syntax. I've also written a TG-to-GXL converter in the process,
>> then realized I wanted a more generalized approach.
>
> An XML graph vocabulary is the obvious lowest-common-denominator 
> representation for TMs, CGs, RDF et al. I haven't (yet) looked deeply 
> into GXL - I have skimmed over some of the pages from Jacks's reference. 
> My feeling is that GXL as a vocabulary is interesting though as you 
> point out somewhat limiting for use by humans because of its verbosity. 
> In using it as a lingua-franca for different represntational forms, you 
> will undoubtedly run into semantic problems. However, having said all 
> that, the nice simple graph model that GXL encodes would be an 
> interesting basis for a "node engine" that handles multiple higher-level 
> representations of which TM4J could be one.

I don't think GXL will be any more limiting than RDF, in fact I like it
a lot better than RDF as a syntax because it doesn't mix the lexical
with the grammar, no XML namespaces, etc. I think Jack, you and I are
thinking pretty alike on this. I'm just watching as the GXL researchers
develop a suitable schema language -- there's been a post recently in
this regard on their mailing list, but I've not had time to investigate
further.

Cheers,

Murray