A new beta version of Google Earth for Mac OS X is available for download. If you’re still running Mac OS 10.3.9 you’ll probably be pleased to hear that GE now supports your system. (via Google Earth Blog)
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Tag Archive for 'Google Earth'
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The hype about Google Earth even gets more interesting as they joined OGC as principal member. Can we expect an OGC interoperable Google Earth in near future? (via All Points Blog)
Looking at those screenshots I suppose Arc2Earth is going to be my favorite piece of software in the year 2006.
Stefan from Ogle Earth links to a very interesting online article in the San Francisco Chronicle about how Google Earth is changing the way environmentalists work.
I think it’s not only limited to environemtalists, in my opinion Google Earth is changing a lot more work environments though. As employee of a company which deals mainly with spatial planning issues I can see how Google Earth gets more and more used and accepted by my colleagues. The main advantage is the extremely fast and free availability of basic geodata (especially aerial and satellite imagery) which was a few years ago difficult to get and mostly not affordable within our project budgets.
Google Earth helps us to easily validate locations. We can compare given land use plans against actual land use and validate certain input data. It’s not our main task to validate or create data so we don’t have base material for that purposes readily available. But from time to time we need to check certain locations on a larger scale and until now it was only possible if you have good knowledge of that places or you try to get more accurate material from certain sources which usually takes a long time in Austria. The combination of Google Earth and professional GIS tools even more simplifies this process. I can integrate and rudimentary display my own data in Google Earth.
On the other side, because Google Earth is a freely available application, I can publish my data as KML and offer it to our clients. Even if they are not familiar with GIS tools there is a good chance that they know how to use Google Earth. For our workflow the use of Google Earth is a huge step forward.
My favorite point on what Google Earth is changing is that suddenly former data access constraints do not work anylonger:
“Instead, it’s starting to look like a killer app that could change the power balance between grassroots environmentalists and their adversaries.”
Yes, Google Earth means something like communism to geoinformation. Everyone has (visual) access to every place, worldwide. Nothing remains hidden. As long as Google and certain governments limit their urge to censor maps.
Google Earth for Mac OS X (10.4) is now officially available for download here! This time it seems to be an authentic Mac version without any weird Direct X preferences.
The proposed use of Google Earth to mark some places and produce simple datasets emerged as big success and was widely adopted by some of my colleagues. Actually one of them is using Google Earth pretty intensive.
So I extended my begun KML to CSV XSL stylesheet to take over Google Earth KMLs in a more convenient way. With the help of this XSL stylesheet you can transform a KML to a GML file. As input examples I took the three listings at Keyholes KML-tutorial. They cover three geometry types, so the developed XSL stylesheet should support:
- Placemarks
- Paths
- Polygons.
With the help of Marc Liyanages TestXSLT I was able to test my XSL stylesheet against Sablotron, Gnome Libxslt, Saxon and Xalan-J. You’ll need one of those (or any other) XSLT processor to transform your KML to GML.
For processing XSLT on Mac OS X you can just use Marcs application, it’s easy to use and extremely helpful for developing and testing XSLT.
An online implementation of Gnome libxslt you can find here. Just copy & paste my XSL stylesheet and your KML into the corresponding fields and hit process. Copy the result in any text editor and save it as GML. E voilà!
How to transform XML with a simple java application is described in that tutorial and based on .NET here.
As in the former KML to CSV transformation you first have to delete the KML namespace declaration before processing your KML, otherwise it won’t work:
xmlns="http://earth.google.com/kml/2.0"
If you want to get some ESRI shapefiles out of your GML you can further use ogr2ogr for instance:
ogr2ogr -f "ESRI Shapefile" myfile.shp myfile.gml
I only did some very basic testing with Quantum GIS (which opens GML directly) and ArcGIS (via ogr2ogr). Possibly it won’t work with every KML.
Suggestions will be appreciated!
On my morning news check I found an interesting link. Seems to be a Mac OS X beta version of Google Earth. Unfortunately I can’t download and test it right now, but there are already a few screenshots and reviews around.
Update:
At home and able to test Google Earth on Mac OS X: on an iMac G5 2GHz RevB equipped with 1.5 GB RAM and connected via 3072/384 kbps to the internet it works nicely! After observing memory & cpu consumption for a while I would suggest to stuff some extra memory into your Mac before using Google Earth. Well, some extra memory for Mac OS X is always a good advice. IMHO the performance is comparable to the Windows XP machine in my office (a P4 3GHz with 1GB RAM). Anyhow, great to see Google Earth finally on Mac OS X!!
Note:
The link above obviously leads to a leaked beta version of Google Earth for Mac OS X hosted by yousendit.com. If you think this download violates your rights please send any further comments directly to abuse@yousendit.com.
Today I had to take over some places a collegue marked in Google Earth. Maybe I was too blind or actually too stupid but I was not able find a simple tool for converting KML to an ArcGIS-compatible format. Except FME of course, but that would be the overkill for my purposes. So I wrote a quick and dirty XSLT-hack to convert a KML-file to a very basic CSV-structure, which I could later import as X/Y coordinates to ArcGIS.
I had following structure in Google Earth:
My Places
__Folder
____Placemark 1
____Placemark 2
Saving the folder as kml brought me this file (GE_original.kml).
For some reasons (I’m no XSLT expert) I had to delete the KML namespace declaration and of course add the XSL-stylesheet information. See the modified KML file here (GE_modified.kml).
The XSL-file I wrote you can find here (kml2csv.xsl).
Put your modfied KML file in the same folder as kml2csv.xsl and open it in a XSLT compatible Browser. You should see now coordinates and placemark names in a CSV structure instead of a KML-XML-tree:
Name,X,Y,Z
Placemark 1,13.08349600542125,47.79234503541417,0
Placemark 2,13.27061184961974,47.68484958984244,0
Save it as text file, open it in ArcGIS (or in your prefered GIS client, spatially enabled DBMS, spreadsheet app or wherever you want) and add the X/Y coordinates to your layer. For now the XSLT is limited to placemarks and it only works if your placemarks are contained by exactly one folder – as I said, a quick and dirty hack.
Further improvements to come (as soon as I have some time left):
- the conversion of KML to GML would be a more elegant way
- support of lines and polygons
Google Earth is a nifty tool to create some spatial notes and simple geographic objects. It’s easy to use, offers access to basic geodata but it’s definitely not a tool to produce large and complex geodatasets.
A useful document if you want to create KML files: Google Earth KML Tutorial.
“I believe we need a ‘Digital Earth’. A multi-resolution, three-dimensional representation of the planet, into which we can embed vast quantities of geo-referenced data.”
(Al Gore, Vice president of the United States of America, 1998)