Google Earth and .kml · PDF file1 Google Earth and .kml files GeoSci020 Class Trainers’ Forum Summer Camp Overview of Presentation • Discussion of GeoSci020 Projects –Q and

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Google Earth and .kmlfiles

GeoSci020 ClassTrainers’ Forum Summer

Camp

Overview of Presentation

• Discussion of GeoSci020 Projects–Q and A

• Overview of components and process–Q and A

• More detailed discussion of specific components (if time permits)–Q and A

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Use in GeoSci020

• 2 different lab assignments with 2 different goals– stream flow analysis assignment– rock identification assignment

Stream Flow• http://www.de2.psu.edu/faculty/uxg3/google/parivers/

• Use real-time data provided by USGS water monitoring stations along PA rivers–Google Earth used as the interface to

provide access to all data points• e.g. links to USGS web sites

– Put in context where these rivers and stations are located in PA

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Clicking on a link on a web page downloads a .kml file and launches Google Earth to display the coordinates and points defined in the .kml file

Clicking on a point in Google Earth opens a description containing information about that water monitoring station.

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Clicking on link in description opens URL in lower portion of Google Earth window.

Cumberland Cemetery• http://www.de2.psu.edu/faculty/uxg3/google/cumberland/

• Geoarchaeological exercise looking at design and different weathering patterns depending on type of stone used for a tombstone–Google Earth used as a backup in

case of inclement weather (snow) limited access to cemetery

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Web page created and linked to from ANGEL.

Clicking on link downloads .kml file and launched Google Earth.

Points (push pins) mark (via lat/long) location of each tombstone to be studied. Each student assigned specific letters (tombstones)

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Clicking on push pin opens description including link to web page with supporting materials (images).

Questions on GeoSci020 Projects

Please save ‘how-to’questions until next section.

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Screen capture of Google Earth showing 3 locations in Valley Forge National Park

Methods Explored for Project• Google Maps API• Use of .kml files

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Google Maps API

• Must request a ‘key’ from Google• Much more flexibility• Much more programming• Did not see any real benefit in Google

Earth but hope to do more testing• If interested -

– “Beginning Google Maps Applications with PHP and AJAX” Michael Purvis, Jeffrey Sambells, and Cameron Turner

Use of .kml files

• Less functionality but more flexibility since key not required– .kml file is a simple text file containing

latitude and longitude– .kml file is an XML document with specific

tags unique for Google Earth/Maps• Simple copy/paste to add more locations

• User must have Google Earth installed

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Google Earth

• Current version is 4.1• Free version sufficient• Mac / Windows versions• Download - http://earth.google.com

• Possible to use Google Maps w/.kml files if it is not possible to download Google Earth

Coordinates

• Need latitude and longitude of each location in decimal form–More decimal places, greater

accuracy• Google Earth supports up to 10 decimal

places

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Coordinates

• Use GPS Unit and record latitude / longitude of each location

• Use http://lat-long.com–Allows searching by location

• Convert to decimal format– http://www.calculatorcat.com/latitude_longitude.phtml

Screen capture of lat-long.com searching on Pennsylvania and then Valley Forge

Screen capture of calculator input

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Create .kml file

• Simple text file created by Notepad, Dreamweaver, TextEdit(Mac)

• XML file with specific code used by Google Earth / Maps

<?xml version="1.0" encoding="UTF-8"?><kml xmlns="http://earth.google.com/kml/2.1"><Document>

<Placemark><name>Anthony Wayne Statue</name><description>Information about location</description><Point><coordinates>-75.444472,40.08639,0</coordinates>

</Point></Placemark>

</Document></kml>

The code below, saved as a .kml document (e.g. vf.kml)and launched in Google Earth will produce 1 point.

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<?xml version="1.0" encoding="UTF-8"?><kml xmlns="http://earth.google.com/kml/2.1"><Document><Placemark><name>Muhlenberg's Brigade</name><description><![CDATA[<h3>Field</h3> <a

href="http://www.de.psu.edu/">Intelligently places itself at the height of the underlying terrain.</a>]]></description>

<Point><coordinates>-75.4258,40.0972,0</coordinates>

</Point></Placemark>

</Document></kml> Addition of the ![CDATA[ …]]

statement in the <description> statement allows for html code to be added

Create any ‘support’documents• Optional

–Additional html pages containing more information about the locations (e.g. images, text, etc.)

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Test locally

• Click and drag icon of .kml file over Google Earth icon to launch Google Earth using the .kml file to load the data

Each time Google Earth loads a .kml file, it is stored in ‘Temporary Places’. During testing, you will not want to save these items. If you do save a test .kml file, it is possible to delete the file from ‘Temporary Places’ (right-click, delete)

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Moving files to web server

• IF Google Earth not used (using Google Maps instead) - create web page with a link containing following code– href="http://maps.google.com/maps?f=q&hl=en&q=http://

www.de2.psu.edu/faculty/uxg3/google/parivers/SchuylkillandSusquehannaRivers.kml"

1st URL address of Google maps with code to launch external .kml file

2nd URL address of your .kml file

Moving files to web server

• IF Google Earth to be used, following MIME types needed– AddType application/vnd.google-earth.kml+xml .kml

– AddType application/vnd.google-earth.kmz .kmz

• Add to web server• If using www.personal.psu.edu - create a

file named .htaccess in any subdirectory containing the .kml file

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• Use Notepad, Dreamweaver, etc. to create a file with these 2 lines– AddType application/vnd.google-earth.kml+xml .kml– AddType application/vnd.google-earth.kmz .kmz

• Save with a name of .htaccess• Copy to a folder on ‘personal’

– The .htaccess file name is used for many things on an Apache web server. It will become ‘hidden’ when copied.

You may also experience problems attempting to name a file with only an extension (e.g. .htaccess). If so, give it a temp. name and then use the Portal to rename the file once it is in www.personal.psu.edu

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Review of using .kml files

• Decide Google Earth / Google Maps• Get lat/long coordinates in decimal• Build .kml file with text editor

Google Earth w/.kml

• Build web page with link to .kmlfile

• Move both to web server• Add MIME types

– .htaccess if Apache web server

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Google Maps and .kml

• Build web page with link to Google Maps–Link needs to contain some specific

code and the URL (web) address of the .kml file

Questions on Components and Process