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Is GML a "Format"?

posted by Satri on Thursday November 10, @10:00AM        Permalink  Trackback URI  Slashdotthis  Diggthis  Del.icio.us
from the concepts-and-wilderness dept.

The Geo-web blog as a discussion wondering if GML is a "format". From the blog: "GML is NOT a format. Creators of software that read or write GML do not think of how the XML is layed out in a file and have no access to it. There are specifications for the length of records or even the order of records within a file structure. Software accesses the data through various data models built by parser (e.g. DOM, SAX etc.) and in which the items of interest are defined by the associated XML Schema (GML Application Schema)."

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• James Fee on this

  (Score:1)

  by Satri (3) on Friday November 11, @09:40AM (#195)
  ( http://alexandreleroux.blogspot.com/ | Last Journal: Friday March 17, @05:07PM )

  Spatially Adjusted blogged about this:
  http://www.spatiallyadjusted.com/2005/11/10/the-pr oblem-with-gml [spatiallyadjusted.com]
• Simplicity and GML

  (Score:1)

  by Satri (3) on Friday November 11, @09:47AM (#197)
  ( http://alexandreleroux.blogspot.com/ | Last Journal: Friday March 17, @05:07PM )

  Humm... another interesting entry from Jeff Thurston's Vector One:
  «One of the entries to the discussion caught my attention. Ron Lake, speaking about the topic of simplicity and the ongoing discussions said:
  I guess I must say I am tired of this mantra of “simplicity” – as if simplicity itself just by some sort of wishing can transcend reality.
  Ron Lake for those unaware is the original author of Geography Mark-up Language (GML). His comments are right on the money and I agree.»
  
  Read it all on:
  http://geovisualisation.com/WordPress/?p=192 [geovisualisation.com]
• Ron doesn't go far enough

  (Score:3, Interesting)

  by Ben (62) on Sunday November 13, @04:08PM (#200)
  ( http://vterrain.org/ )

  Ron says GML isn't a format because it's a logical, rather than physical description of what goes into a file. He's absolutely right, but doesn't go far enough. GML isn't a "file format", in the way most people use the term, because it doesn't even describe a single set of logical descriptions. Instead, you must make a "profile" of GML in order to describe anything. GML is something more like a "format description language", a set of building blocks for you to define a file format. Hence, statements like "convert from GML" or "convert to GML" are meaningless.
  
  If you create a file formats which is built on top of GML, say "ABC", then it could be meaningful to talk of "converting to ABC". However, there is no such thing as "raw" GML.
  
  The number of people that understand this so far is a tiny fraction of those who are jumping into GML, which i find horribly frustrating, to the point where i must conclude that GML's complexity is so far beyond most people's comprehension that it proves ultimately fatal to GML's adoption.