Tripping the Bits
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FOSS4G NA 2012

Here's a collection of raw notes I took at sessions during FOSS4G NA 2012.


  • PostgreSQL 9.2 in about September
  • many geeky performance updates
  • index-only scans will affect spatial data the most
  • new visiblilty map: in-memory bitmap of data currently loaded
  • takes 1% as long as getting this info from the physical table (heap)
  • read/write scalability; better support for cloud hosting
  • cascading replication & other replication improvements
  • multi-master replication, hopefully in 9.3
  • "I don't know how it's going to happen, but it has to."
  • we love "weird data", e.g., spatial data
  • new weird data in 9.2 is JSON!!!!
  • JSON <==> Hstore for indexed JSON!
  • write views in JavaScript!
  • spatial index directly in PostgreSQL, should (will?) be used in PostGIS 2.1


  • presented by: @jatorre
  • some new, awesome apps using CartoDB
  • CartoDB demo
  • download wifi hotspot data from NYC OpenData
  • support different data types (spoke too fast), zipped shape files
  • drag & drop from desktop
  • I wonder if they fixed the issue where uploading a .geojson export from QGIS failed
  • can edit geometry when designing map
  • individual vertex editing for polygons
  • style with CartoCSS
  • uses new PostGIS 2.0 already
  • can query for styled tiles with "Maps API"; style query string argument
  • can query for actual data with "SQL API"
  • can use new PostgreSQL index nearest query
  • "I have seen the future and it is not made of tiles"
  • I would say: not only made of tiles
  • 8 Bic map demo looks great!
  • open source; they make money from tiered hosting plans
  • free tier
  • can import OSM data


  • presented by: @tmcw
  • presentation is here:
  • Google "begat" Maps API because people were creating their own mashups by hand
  • open source options adopt big software company's interface to help with conversion
  • google helped change mapping
  • tiles don't need to reload
  • cartography: not all roads need to be shown
  • start thinking in frames per second
  • eliminate old ideas users don't care about: scale bar
  • users can make/design maps with greater detail than any company (including MapBox)

UX Panel

  • why does the interface suck?
  • the more stuff your product does, the more complicated the ui has to be
  • we have to get designers involved because we're software engineers
  • is $1M the price of a good UI?
  • current OSM UI already cost well over $1M in time


  • github gives credit to more contributors
  • good mobile support
  • tile animation
  • new Zoom control (only +/- buttons)
  • nice accessability features
  • writes tiles to localStorage automatically?
  • do they know there's not much space for that? Can we shut it off?
  • the important part about HTML5 is that you think it's cool
  • UTFGrid integration
  • continuous zooming
  • does it switch to higher tile zoom (and scale backwards) at a middle threshold?
  • improved APIs
  • can pass plain objects to some functions
  • can abort tiles
  • OpenLayers is the cat chasing a mouse
  • "There's some question about the size of the cat."
  • hosted build tool would be an improvement

OpenLayers in 3D

  • presented by: @pelicanmapping
  • original plugin didn't work in Chrome
  • nice 3D mountain demo
  • OpenLayers 2D to 3D with a click of a checkbox
  • GeoTIFF to encode elevation data = "home grown, JSON-encoded tile" = nice idea!


  • NOT backwards compatible
  • because serialize to disk is different
  • PostGIS 1 had unaligned data storage
  • new 3D functions: ST_3dDistance, etc.
  • new 3D types: triangle, tin
  • 3D index-based query: &&&
  • new PostGIS connection GUI
  • batch shapefile loading in the GUI
  • dump spatial tables to shapefiles
  • geometry data type can include geometry type, e.g., MultiPolygon, and SRID
  • can still use un-typed geometry table
  • better raster support
  • load raster with raster2pgsql command
  • join between raster and geometry tables?
  • rasters are large collections of tiny chips
  • rasters are for analysis, not visualization
  • can snap rows: ST_Snap "work in progress, but mostly works"
  • force features to valid: ST_MakeValid
  • nearest neighbor indexed searches
  • order by geom <-> ... limit 10

jQuery Geo

<shameless plug />
  • presented by: @ryanttb
  • AppGeo has had an internal map widget for over eight years
  • feature set akin to OpenLayers, size close to Modest Maps
  • "jQuery Geo is designed to change the way that you write JavaScript...for mapping"
  • like jQuery, one script tag hosted on worldwide CDN
  • can use map services not in web mercator

Challenges Panel


  • 200,000 employees in all agencies
  • moderate degree of specialization
  • low degree of colabaration between agencies
  • 17 developers/analysis in department
  • everything built internally, maintained internally
  • some apps have lived many, many years past their lifespan
  • in house mapping framework developed 4/5 years ago (open layers wasn't ready yet)
  • geoserver in that framework, as is geowebcache
  • app shows all streets that are closed, based on OpenGeo stack w/o PostGIS (because Oracle shop)
  • all components available for other city agencies on shared service environment
  • oracle not going away any time soon
  • many other commercial software to integrate
  • painful integration with SharePoint
  • "legacy solutions being built every day"
  • simple operations support doesn't need knowledge transfer, e.g., start/stop services
  • moving off of Solaris to RedHat Linux
  • first group in DoITT to move toward open source
  • it takes leadership to create adoption of open source
  • having a support model around an open source solution is "key"
  • legal issues do not exist, do it and apologize later
  • don't ask attornies unless you have to, they will find things
  • not "most interested" in any one part of OpenGeo stack
  • it's all about what the project needs and what best fits it
  • simulated the traffic hit while trying to generate new tiles, etl, etc. for snow removal app
  • concern is scalability
  • especially on "our antequated servers"
  • OpenGeo team came to help
  • would like to know what community wants from agencies like DoITT
  • biggest app to use OpenGeo is City Map
  • most popular is snow plow app
  • see us continuing down the open source road
  • excited by projects out there
  • hopefully the agency follows along
  • getting open source software had to go through the same accreditation/security audits of all software


  • brought on for national broadband map
  • many silos in fcc
  • focus on what we can do in the future
  • broadband map introduced new technologies to fcc
  • agency has a lot of QGIS usage
  • people have come to it w/o thinking a GIS problem, but to look at data, e.g., census
  • use MapBox & TileMill for authoring Maps (publish all maps on
  • legacy of expertise, esp. in database
  • PostgreSQL wasn't mature enough at the time for some projects
  • idea of moving to more loosly-coupled systems
  • should be able to work from an API call instead of proprietary third party solution
  • open source developers used to doing a lot of system admin, usually have root access
  • now, ops admins don't let devs get too close to hardware
  • but devs are trying to push that boundary
  • internally, you need to cultivate change (to open source)
  • most users don't care if they're using open source, some seek it out
  • if there's a license that other agencies have used, then there's not much to worry about
  • PostGIS on a super computer can do a lot of analysis
  • didn't offer horizontal scaling that IT staff thought it could
  • "OpenGeo team scrambled to support us"
  • likes that people want to build apps around government data
  • having open APIs is a way we give back
  • giving code back to the community is good (open sourced Drupal code for MapBox)
  • part of RFQs now mention that source must be put on public site like github
  • some good ideas snuck through with broadband map
  • fully RESTful
  • use OGC
  • app must use own API
  • would like to stop hosting own hardware
  • see us moving geoserver to cloud space
  • looking for OpenGeo to guide us

Round trip

I had a great time at FOSS4G NA and look forward to a great year of open source!


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