Monthly Archives: July 2012

Exporting vector layer as kml in QGIS

In my previous post I described how to export a vector layer from GRASS GIS as kml file. The key was to use the dsco parameter to define the columns that should be used for the Name and Description fields in your kml file.

In QGIS you use the ‘save as’ option in QGIS. You can get this using the context menu (right click mouse on the layer) or the menu ‘Layer | Save as..’. In the menu that opens, there are two fields under the header ‘OGR creation options’; ‘Data source’ and ‘Layer’. Continue reading

Exporting point file as kml in GRASS GIS

The v.out.ogr function in GRASS GIS let you export your vector layer to any format supported by OGR (it is basically an interface to the GDAL/OGR function ogr2ogr). This includes kml files. E.g.,

v.out.ogr input=labels layer=1 dsn=/home/paulo/test.kml format=KML

will export the vector layer ‘labels’ as the kml file test.kml Continue reading

Creating alternative emails from your gmail

In Gmail there is no easy way to sort. The good folks at Google seem to have this idea that everything should be done by searching. Sure, I use the search function all the time. But really… No option to sort your emails on anything other then date?!

Anyway, while looking for ways to sort my emails in Gmail, I came across this site with a few tips on sorting your email. It mentioned one feature I had not heard of before, the option to create new Gmail ID’s with a plus (+).  Continue reading

A great way to try out open source GIS software

I just came across an email thread on the QGIS email list that mentioned OSGeo-Live. This is a “self-contained bootable DVD, USB thumb drive or Virtual Machine based on Xubuntu, that allows you to try a wide variety of open source geospatial software without installing anything”. Worth exploring if you are looking for new great geospatial software.

From multiple rasters to one Google earth layer

To create a Google earth map, I would normally export my raster layers as a geo-referenced png file and subsequently use maptiler (or gdal2tiles.py) to create the Google earth map (see here for more details). Because I want to create a map based on several layers, I can not simply export a raster layer. Instead, I need to create a map in QGIS map composer and georeference that map, following the steps described here.

Unfortunately, as it turns out there are limits in the size of the map you can create in QGIS map composer. Perhaps there is a way to increase this, but I am not sure how. An alternative solution is to smaller create sub-sets of the map. But how to get them together as one Google earth map again? Continue reading