Sat, 25 Feb 2006

World Wind and shapefiles

How should NASA's World Wind handle the introduction of a shapefile layer? Well, I can think of two reasonable ways to do this.

  1. somewhere there exists a .zip file containing the three component files of the shapefile. A third party has written an XML which describes how they want that shapefile drawn (e.g. with and without labels). Their XML file specifies the URL of the shapefile.
  2. somebody wants to publish a shapefile directly usable by WW. They create the .zip with the three shapefile files, and add to it the .xml needed by WW.

    I can think of only one benefit to #2: you don't have to deal with telling your webserver that a .xml file is an XML file rather than some kind of mutant HTML. A big advantage of #1 is that anybody can describe anybody else's file for use in WW, *and* they don't have to host that shapefile.

    We could support both formats, of course. If you tell WW to use a shapefile, WW could look at the filetype / extension. If it's XML, then the XML specifies the shapefile with a URL. If it's .zip, then the .zip contains the XML file.

    Now, the second question is how to handle versions. Is there any reason to keep permanently a shapefile given that WW doesn't permanently keep any imagery data? Basically, WW is an online data viewer and only caches imagery data. Why should it save a shapefile? Thus, whenever you turn on a shapefile, WW should re-fetch the shapefile (checking the HEAD just as a web browser does). If somebody *really* wants to display local data, they can specify file:// as the URL.

Posted [22:14] [Filed in: gis] [permalink] [Google for the title] [digg this]

"Our Oil?"

Various people claim that we are in Iraq to protect "our oil".

What you mean "our oil", Kimosabe? Yes, many people make the charge that our military presence is in Iraq to protect "our oil"? If that's true, then we ought to be in some way exploiting our franchise. For example, other countries might only be able to buy a limited amount of "our oil". Or we might get "our oil" prior to other countries. Or other countries might have to pay a higher price for "our oil".

I think it's possible to make the case that our military is protecting "our oil". To do so, you would have to present evidence that we are treating it like "our oil". If you can't do that, then you have to make the claim that we are expending treasure and lives to protect other people's access to oil. We might be doing so -- but if we are, you can't argue that we're being selfish.

Posted [15:09] [Filed in: economics] [permalink] [Google for the title] [digg this]