Surveying, Mapping and GIS

It's been a very busy few weeks, so I haven't had much chance to post... things going on with Virtual Earth, ArcIMS Route Server and GDT/TeleAtlas, survey-grade GPS data collection, emergency response, logistics, modeling and simulation, and plenty of other things flying around.

It's all fun stuff, but I always enjoy rolling the sleeves up and getting dirty... doing the AJAX thing, mashing various web services with Virtual Earth's V5 API via pure JavaScript clients as various proof-of-concept applications.

Here's one quick app: Virtual Earth and the NASA MODIS WMS server:

Here I'm showing the VE and MODIS side-by-side, both views refresh dynamically. The next step will be to explore the "Roll Your Own Tile Server" approach to seamlessly getting custom WMS content directly into VE.

The next one was even more fun: Virtual Earth and the MetaCarta JSON API:All pure Web 2.0, neogeo, slippy AJAXIAN goodness, "Look, Ma! No "SUBMIT" button!!" Type in your query, (searching for documents about toxic substances here...) and it fetches results from the MetaCarta appliance and sprays them back into the VE map view. Pan, zoom, and instantly you get new stuff popping up. All self-contained in a few k of DHTML, CSS and JavaScript, no Java, .NET, Ruby, Python or other infrastructure needed. Both written in a total of about 2.5 hours, just noodling around in the APIs without any real thought ahead of time.

As I mentioned a few days ago, I was just finishing reading one of the books in the "Head First" series that Kathy Sierra developed, namely Head Rush Ajax by Brett McLaughlin.

This is a fun read. It really makes Ajax very easy and accessible, with a fun dialogue, irreverent and entertaining style, and plenty of practical examples and online code to work with. I have been playing with Ajax code since around November of 2005, but largely just hacked my way through most of it, brute-force-style, without any coherent source of information, other than the school of hard knocks.

As such, I figured there might be a few areas where I might grumble through the but given there were a lot of things that I already knew, but on the other hand I still learned quite a few nuances and new things while reading this book.

The book presents Ajax in a good, progressive way, with bite-sized yet savory nuggets, which all contribute to a soundly filled tummy full of Ajax. Unlike many of the technical tomes I digest routinely, this one didn't put me to sleep. It was deceptively simple in how the book followed a linear progression, with each piece building upon the one before it - it's not at all written "reference-style" with disconnected globs of information as so many other technical tomes tend to be.

True, some parts of the book were still perhaps overly "nØØb"-oriented (for me at least) and overly rich with "greasy kid stuff" but that's not necessarily a bad thing. The way that the book tackled otherwise sticky topics, such as navigating and managing the DOM was nice, as were the ways in which a request is sent, processed and received. All in all, the presentation was quite robust, with no meaningful detail omitted.

The only downsides: 1. The emphasis on JSON toward the end. I have expressed my bias and concern regarding JSON before, mainly as I still cling to the paradigm of not only server-to-client communication via XML, but also server-to-server communication. 2. It had a PHP focus - I don't deal much with PHP, mainly .NET and Java.

As an aside, two things I'd like to see some objective study someday on:

• How truly bloated is XML, compared to JSON? Seems JSON can suffer from its share of bloat as well.
• How much is JSON supported on the server side. Not just libraries for generating JSON, but also libraries for parsing and processing JSON? What languages? Seems to me that generating JSON might be the easy part, even doable through XSLT transforms - but parsing?

Though I wasn't able to attend ESRI DevSummit 07, I did get some good feedback - my own people report on the continued push toward web-based GIS and server-based GIS and SOA, with SOAP, REST, JavaScript and AJAX APIs being made available, along with tremendous demand from the .NET developer community.

I also scoured the blogosphere and scavenged together a set of posts and resources - dig through these, as there are copious notes, slides and podcasts to be had.

In no particular order:



Very Spatial 3/28: Dev Summit Overview "VSTV Episode 12": http://veryspatial.com/?p=1486

Very Spatial 3/28: Daily Podcasts: http://veryspatial.com/?p=1485

Very Spatial 3/26: Daily Podcast talking to DevSummit Attendees: http://veryspatial.com/?p=1478

Very Spatial 3/24: Standards and Interoperability Podcast: http://veryspatial.com/?p=1475

Very Spatial 3/23: ArcWeb Services Podcast: http://veryspatial.com/?p=1473

Very Spatial 3/22: ESRI Support Team Podcast: http://veryspatial.com/?p=1471

Very Spatial 3/22: Keynote Session Podcast: http://veryspatial.com/?p=1468

Very Spatial 3/21: Keynote Comments: http://veryspatial.com/?p=1466

Very Spatial 3/21: Gartner Keynote: http://veryspatial.com/?p=1463

Very Spatial 3/20: Plenary Session Podcast: http://veryspatial.com/?p=1462

Very Spatial 3/20: Plenary Part 2: http://veryspatial.com/?p=1458

Very Spatial 3/20: Plenary Session: http://veryspatial.com/?p=1457

Very Spatial 3/18: Preconference Podcast: http://veryspatial.com/?p=1453

After a great meeting this afternoon, I am looking to rehash some of my previous MetaCarta work. Looks like some of the previous kinks that I was running into with using a SOAP call to the HeadNode service originally developed on MetaCarta 3.0.1 have been worked out in newer versions (we are currently standing up two boxes with 3.7), and further, it may be a good opportunity to look at the JSON API that MetaCarta has developed.

I am also anxiously awaiting some of the document focus and other enhancements that MetaCarta has coming down the pike later this year. Other things I'd like to look at are streamlined, enhanced and more-focused document crawling.