Tag Archives: symbols

Maps, missiles, and moving labels

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This is my second fear mongering post seemingly focused on 10,000km-range North Korean missiles (the first can be found here). I’m really not all that concerned about North Korean missiles in my day-to-day life. The real point of this post is that the web map (here) features animated SVG symbols that are (that is, appear to be) animated along circles, not simple polylines (they actually are polylines in the shape of geodesic circles). Also, notice that the “symbols” are in fact numbers, not simple shapes, which took a while to code, so I hope you enjoy them.

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Are you within reach of North Korea?

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Want to know if you’ll be safe from North Korea’s 10,000km-range rockets? Here’s a map to figure it out. Interesting fact: the border between Glendale and Phoenix, AZ is 10,000km from Pyongyang.

Note: my web map is a total, shameless, absolute rip-off of the very interesting post and map presented on the disastermapping blog.

Random Movement, Dynamic Symbology: Part II

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After another round of revisions, here is a randomized example of the grizzly bear/oil well animation (first draft here).

Changes:

– swapped heat map for bread crumbs

– smoke rings appear at visited wells

– terrain map changed for satellite

– toned down oil well symbology

– improved algorithm calculating distance to wells

Update: FRI AGM Tour Route

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Above is an update on last month’s post, FRI AGM Tour Route. The new features include: a jQuery UI accordion control (for “Tour Information” and “What to Bring” sections) and a styled, animated bus symbol.

Random Movement, Dynamic Symbology

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Here‘s another visualization I’ve been working on. Lots of wildlife biology these days deals with how animals interact with the human world around them. Here in the forests of western Alberta, that generally means either forestry activity (cutblocks) or oil infrastructure (wells, pipelines, seismic lines, facilities, etc.). This is a proof-of-concept map, showing a randomized individual (maybe a bear…?) moving amongst randomly placed points (maybe oil wells…?). As the individual moves closer to a point, the point size increases.

The tricky part was managing the distance calculations. It was bogging down in the attempt to calculate the distance to every point on the map (500 of them) each time a new point was drawn. To overcome this limitation, I set it so for every 25 new locations it would find all of the points within 50km and remember them – usually it was about 50 points. Then, for each newly drawn point, it would cycle through only those 50 nearest points and adjust their symbology to be inversely related to distance.

Note: works fine in Chrome, not so well in Firefox, and don’t even bother trying it in Internet Explorer.

FRI AGM Tour Route – Preliminary

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The Foothills Research Institute’s Annual General Meeting is approaching, and part of it will be an interpretive bus tour. Above is a draft version of the bus tour, showing some of the stops (they could very well change in the future). More to my tastes, the map uses the Google Maps API in a variety of ways, including calculating optimal directions between waypoints to produce the polyline, and animating both marker and polyline symbols. Future development will focus on loading content into infowindows.

Visualize GPS Data in Google Maps

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Obviously, maps are a great way to show spatial data. But have you ever tried to show how things on the landscape change through time? Where do animals move, where are wildfires burning, where are Mountain Pine Beetles going to and coming from? Most often, this is accomplished by showing a series of maps – lifeless, static, blah. The map series can be animated by certain pieces of software (generally costing a pretty penny), but we haven’t found anything nearly as smooth as what we’ve produced using a little bit of Python programming to format GPS data, and HTML/Javascript to display the animated map using the Google Maps API (a way for the public to use the Google Maps framework). This is all free of charge, by the way.

The Grizzly Bear Program at the Foothills Research Institute have fitted several bears with GPS collars. They collect an immense amount of locations and give an awful lot of presentations; showing those paths in an engaging way is important. The solution Python-whiz Julie Duval and I came up with takes GPS location files (text files), and produces an HTML file ready to display an animated map of bear movements on a Google Map.

You can look at an example here, although it only shows randomly generated paths – sorry, I can’t show you the location of local grizzly bears! The site is best viewed in Chrome or Firefox, not Internet Explorer.

If you are an FRI partner, please contact me (dwiens@foothillsri.ca) for more information on how you might better display your time-dependent data. Also, in a few days we should have a distributable copy of the ArcGIS script tool that you can use to plot your own data on a Google Map (sorry, partners only).