Watercolour OSM maps

It’s possible to do all kinds of custom renderings and create special map views, but this one really wins the prize. Stamen Design has produced a custom OpenStreetMap rendering system that gives you what looks like a hand-drawn watercolour image on fibre paper – beautiful! It’s possible to do all kinds of custom renderings and …

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Rotating a point grid in QGIS

Good ol’ GIS.stackexchange … I finally ended up posting a bounty of 50 reputation points for my rotation problem, and got an answer within a couple of hours! If you want to rotate a grid of points around (originX, originY) and degrees θ, enter the following values into the dialog (see image to the right): Scale …

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The quest for a tool to rotate a point grid …

While writing the Aerial Survey Manual for WCS last year, we decided to do the transect layout in ArcView since UWA was using that application – and rotating a grid of points was fairly straightforward during an edit session. Being able to use this set of points to lay out transects at any arbitrary angle …

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Spatial operations: R vs. spatialite

R and sqlite / spatialite have very different performance for the same spatial operation – in this example, an intersection. The example here is overlaying a point on a set of polygons and returning the data (census tract number). A quick R function that solved the problem (using US census tract data from TIGER): library(maps) …

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Roadsides in Tete

Conservation, counting critters, GIS & miscellanea

I suspect the ‘picnic site’ is the dirt on the right …

This was taken on the way out of Mfuwe, Zambia yesterday morning. This was taken on the way out of Mfuwe, Zambia yesterday morning.

Troubleshooting install of QGIS in OSX

Yesterday afternoon I found I couldn’t run QGIS at all – it kept crashing on startup, whenever it got to the splash page “loading plugins” bit. I tried restarting without plugins running (/Applications/QGIS.app/Contents/MacOS/QGIS –noplugins) but it would still crash when I went to the “Manage Plugins …” menu option, so no chance of turning them …

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Yet another depressing thing about Ricoffy

It never fails to amaze me that, in the continent that hosts the original coffee plants, we continue to suffer with instant coffee pretty much everywhere. In the highlands of northern Tanzania, where there is some dynamite coffee grown and roasted, you’re still likely to be served instant at most guesthouses or mid-range hotels. Thankfully, this …

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