Posts Tagged ‘gis’

Last year I attended and wrote about FOSS4G 2011 in Denver. The 2012 FOSS4G event was supposed to take place in Beijing this September. Last month OSGEO announced that the conference was cancelled.
Cameron Shorter has posted a detailed analysis on how the conference fell apart. His post does a great job of looking at the sequence of events that lead up to the current situation.

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Slides from my 2012 PGCon presentation Making your Own Maps are now available

The presentation covered

  • Common reasons people render their own maps
  • Where to get OpenStreetMap data and how to load it into your PostGIS database
  • How to use Tilemill to design your own map style
  • How to render map tiles, both statically and dynamically
  • How to use OpenLayers to display your map

The presentation was recorded. I will update this post when the recording comes online.

I’ve been a regular attendee of PGCON since the first year it was held in Ottawa. Like past years I enjoyed the conference and I would like to thank Dan Langille for putting together another first-rate conference. My favourite part of PostgreSQL conferences is meeting and reconnecting with users people in the community.

Updated: The video is available here

Peninsula Lake Map

Peninsula Lake, Huntsville Ontario

I have published a new version of the Peninsula Lake map. This edition includes new cartography and map updates based on my survey work last summer.

I had written the previous map style in Cascadnik, a CSS like language that translates to mapnik XML. Cascadnik has since been replaced by Carto so I have decided to rewrite the map style using TileMill (Map design software that uses Carto and Mapnik).

One of my goals while redesigning the map was to put to use what I have learned about cartography over the past year. The original PenLake map style was based on a sample Cascadnik style adapted to my colour scheme, nautical features and a print scale. The new style was designed by me from scratch to focus on

  • The lake and nearby rivers, streams and marshes
  • Recreational attractions around the lake including hotels and golf courses
  • Roads near the lake
  • The water depth of the lake including suspected rocks

This style is much smaller than the previous one ( the style is less than 300 lines of CSS) and it behaves well at different zoom levels between 12 and 18. I suspect the number of layers can still be further reduced for faster rendering times.

I have made a web version of the map available on Peninsula Lake Map my map hosting site. The map tiles are currently being served by MapBox.

Some of the water depth data in this version of the map is based on observations I manually made while kayaking on the lake in the summer of 2011. I have tried to correct this data to match the sounding datum used by the CHS in their observations. I don’t expect the observations taken by me with a kayak, rope and a tape measure to match the accuracy of the CHS with their fancy sonar but we have to work with the equipment that we have available to us. The depths on the map should be based on a datum of 913 feet.

The Source code is still available from github

My talk on PostGIS replication at FOSS4G 2011 went well. It looked like there were about 150 people in the room. Most of them had not yet deployed a PostGIS replication solution.

My talk covered Slony and streaming replication. It gave an overview of different replication patterns that can crop on in the GIS space. I then gave an overview of the key features and limitation of Slony and streaming replication.

A video of the talk is available at FOSSLC

My slides are available here

Peninsula Lake, June 2011

The June 2011 version of the Peninsula lake map is ready. You can download a PDF or get the SVG and the map styles from github

This version includes more buildings, docks and rocks traced into OpenStreetMap from Bing imagery along with a few bay names and some cleaner text. My next step is to try and collect depth data in some areas the that the Hydrological service skipped. I’ve already been out in a kayak with a weighted container and rope trying to develop techniques.

Tonight, I gave a short talk at OpenData, Waterloo Region on ‘Consuming & Presenting OSM Data‘. A discussion on how to use OSM data followed. The audience had a range of OSM experience. Some people had heard of OSM but never used it, a few people had used the data in applications or while traveling and some experienced mappers were also in attendance. The talk was geared to give an introduction to drive an informal discussion/Q&A versus as a ‘how to’ tutorial.

The meetup was held at ‘Mitsy Mountain Coffee‘. Mitsy Mountain is a spacious coffee shop that has room at the back with a meeting table and large screen that can be used by groups such as ours for meetings. Mitsy wasn’t around when I moved out of Waterloo, but seems like a nice place and is worth visiting again the next time I’m in KW.

My slides from the talk are available here
consumingOSMData

Yesterday I attended a meeting of SiliconHalton, a technology group in Halton region. The topic of the meeting was OpenData.

Nik Garkusha, an Open Source strategy lead at Microsoft was gave a really good presentation on what open data is, and why it is important. Based on the quality of Nik’s presentation I suspect that he often gives presentations on Open Data. I particularly liked that he started the presentation talking about how OpenStreetMap was used in Haiti after the earthquake and how crowd sourcing projects are mapping the floods in Quebec and Manitoba.

There were about 30 people in the room and most of them were not ‘opensource’ people. I hope some of them left having a better understanding of open data.

I was also talking to someone who works in the I.T. department of one of the local municipalities. He was saying that they were talking about releasing more of their data under open licenses but are worried about losing revenue. He said they currently charge land developers a lot money for some of the data. As open data advocates, I feel we need to convince these municipalities that the things that can be done by the public when the data is opened outweights the relatively small amount of money they collect selling this data.