Google Earth: Walk-Through / Guide.

[Guest Sid-Vicious]

I posted this in another thread:

I've been and looked at lots of places that i've found on google earth only to find they're shit for one reason or another. Try using google street too if possible. I'd say your lucky if 1 in 10 is any good.

Goggle earth doesn't show pheasant feeders, bee hives, bird boxes, heights of surrounding trees, fences, benches. Loads of things.

IME a good site needs to be scoped out during the day. Unless its a risky one. If you only visit at night you could end up planting 2 steps from a path.

[Toasted]

I was just contemplating checking out a nice long strip of grass and never even thought of Google Earth.

I should, I use it all the time.

You have to remember Google Earth isn't going to show you a field or whatever as it is now, it could be overgrown far more etc, because Google Earth is way out of date, I know this from looking at a car park near me that got resurfaced with black tarmac probably a year ago and it still shows the old grey concrete surface.

Just warning ya, you could go there to find a multistory car park has been slapped on top of where you were gonna grow!

[allcityjunglist]

For those looking for the otherplaces.kmz file, I couldn't find it either, but a quick search helped me out in finding the components of it that you need, the weather overlay and the ordinance survey overlay, here are the links

gavin's unofficial ordinance survey overlay: http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&sqi=2&ved=0CC4QFjAC&url=http%3A%2F%2Fwww.thegeographer.co.uk%2Fuploads%2FGavin's%2520Unofficial%2520OS%2520overlay.kmz&ei=p4l5T5aDHNCp8QPFmdCpDQ&usg=AFQjCNETjyyWNCQefeexj_noy-E1kSn-lw&sig2=Fs-QKvqGkX6QrvgQWOxLQw

it should download as soon as you enter the link

and the UK weather channel maps: https://groups.google.com/a/googleproductforums.com/forum/?fromgroups#!topic/gec-dynamic-data-layers/RgXL5hrXRGQ

when adding these to google earth just follow weed_G's instructions for adding otherplaces.kmz

hope this helps

[kookachu]

Cheers Weed_G, top tutorial mate

And allcityjunglist, cheers for the link... welcome to the site..

[tom420]

Very detailed and helpful post just you lost me a bit there, can't seem to get it to work..

[SamBell]

I have been having a hack at Google Earth and have managed to get it so that Gavin's OS overlay (http://www.brock-family.org/gavin/google-earth/osmaps.html) is partially transparent, meaning you can see Google Earth pictures and OS data at the same time.

The picture from Gavin Brock's site to illustrate what the OS overlay does:

Pretty much the same place and view but with transparent backgrounds on the map tiles:

How this works:

Google Earth's requests are sent through a proxy, Squid.

Squid runs a perl script against every URL requested.

- If the URL is an OS URL it downloads the tile to a temporary location, modifies the tile so that it has transparent background, and redirects Google Earth to a web server serving content from the temporary location.

Software used

The OS I use is Linux, though re-implementing this on OSX should be easy. I think all the software necessary does exist for Windows too, but it will likely be unpleasant to try use that.

Squid

Perl

Imagemagick

wget (though curl can probably be used)

lighttpd (though any web server should work)

Google Earth

Squid configuration:

I only made the following changes to /etc/squid.conf

http_port 31280
url_rewrite_program /tmp/redir.pl
url_rewrite_concurrency 5

I changed the port number as I already use 3128. The URL concurrency has to be greater than 1 else the redirect script doesn't get passed the correct data.

The default settings otherwise seemed fine, though I'm not massively familiar with Squid so it could have some issues or security concerns.

The redirect script:

I saved the script to /tmp/redir.pl as I am lazy, and because Squid forks sub-processes running as nobody, so somewhere nobody could easily read and write was needed.

#!/usr/bin/perl

$|=1;
$count = 0;
$pid = $$;
while (<>) {
   chomp;
   @X = split;
   $url = $X[1];
# Most zoomed out maps
   if ($url =~ /osmapapi\/ts.*LAYERS=100/i) {
       system("/usr/bin/wget", "-q", "-O","/tmp/os/www/tmp/$pid-$count$2", "$url");
       system("/usr/bin/mogrify", "-transparent", "#fcfbeb","/tmp/os/www/tmp/$pid-$count$2");
       system("/bin/chmod", "777", "/tmp/os/www/tmp/$pid-$count$2");
       print $X[0]." 302:http://127.0.0.1:3000/tmp/$pid-$count$2\n";
# Landranger
   } elsif ($url =~ /osmapapi\/ts.*LAYERS=5/i) {
       system("/usr/bin/wget", "-q", "-O","/tmp/os/www/tmp/$pid-$count$2", "$url");
       system("/usr/bin/mogrify", "-transparent", "#ffffff","/tmp/os/www/tmp/$pid-$count$2");
       system("/bin/chmod", "777", "/tmp/os/www/tmp/$pid-$count$2");
       print $X[0]." 302:http://127.0.0.1:3000/tmp/$pid-$count$2\n";
# Zoomed out maps
   } elsif ($url =~ /osmapapi\/ts.*LAYERS=25/i) {
       system("/usr/bin/wget", "-q", "-O","/tmp/os/www/tmp/$pid-$count$2", "$url");
       system("/usr/bin/mogrify", "-transparent", "#fcfcfe","/tmp/os/www/tmp/$pid-$count$2");
       system("/bin/chmod", "777", "/tmp/os/www/tmp/$pid-$count$2");
       print $X[0]." 302:http://127.0.0.1:3000/tmp/$pid-$count$2\n";
# Most zoomed in maps
   } elsif ($url =~ /osmapapi\/ts.*LAYERS=1/i) {
       system("/usr/bin/wget", "-q", "-O","/tmp/os/www/tmp/$pid-$count$2", "$url");
       system("/usr/bin/mogrify", "-transparent", "#ffffee","/tmp/os/www/tmp/$pid-$count$2");
       system("/bin/chmod", "777", "/tmp/os/www/tmp/$pid-$count$2");
       print $X[0]." 302:http://127.0.0.1:3000/tmp/$pid-$count$2\n";
   } else {
       print $X[0]." \n";
   }
 $count++;
}

This script has its roots in one of the upside-down-ternet hacks that is out there. I have just hacked at it and fiddled until I got reasonable results, I am an utter amateur at perl.

The webserver

I just run this as my normal user

$ /usr/sbin/lighttpd -D -f /home/SamBell/bin/os/lighttpd.conf

~/bin/os/lighttpd.conf

server.document-root = "/tmp/os/www/" 

server.port = 3000

mimetype.assign = (
 ".html" => "text/html", 
 ".htm" => "text/html", 
 ".txt" => "text/plain",
 ".jpg" => "image/jpeg",
 ".png" => "image/png",
 ""     => "image/png"
)

dir-listing.activate = "enable" 

Google Earth

And finally I start Google Earth, telling it to use Squid running locally as the proxy.

$ HTTP_PROXY=http://127.0.0.1:31280 googleearth

This arrangement works for all the different zoom levels the OS maps provide, and as Manchester Airport is in the news today I have picked there to take a couple more screenshots.

Hope this is of use to some guerillas out there!

E2A: The temporary location will need clearing out of files once the Google Earth session is done too, to save wasting disk space.

Edited June 7, 2012 by SamBell

[matty970]

very informative sam but fuck me drunk it may aswell b in japaneze

[eye 1 der]

a great tool for checking aspect, access and privacy but i wouldnt be placing location pins ...found many great places for GG dont disregard 'brown field sites' and industrial parks if you can get in and out easy..sewerage works are a firm favorite, once used 2 sheets of kingspan to get out onto slurry lagoons(be very careful its very easy to get over your head in deep shit!)but its free fertilizer and not requiring watering

[Mattock Man]

is it just me or is the sun/timeslider designed to be impossible to use?

driving me round the fucking bend - I have a computer based degree Im not an idiot but I just cant get it to work like in the tutorial - hit and miss doesnt come ino it ita all miss.

This is like the fifth time ive given it a go with the same result..

The settings window will only let me set 1 date (the start date is greyed out)

try as I might i cant get it to display a sinle day of sun over the landscape

shittest part of the application it may as well no be there.

Ive had to resort to drawing paths to try and get an idea of sun activity east to west but obviously this doesnt come close to what the sun really does in summer

[ismokepot]

Same problem earlier Freda, also I accidentally got stuck in star mode? confused the hell out of me xD

[Pierresenberg]

is it just me or is the sun/timeslider designed to be impossible to use?

driving me round the fucking bend - I have a computer based degree Im not an idiot but I just cant get it to work like in the tutorial - hit and miss doesnt come ino it ita all miss.

This is like the fifth time ive given it a go with the same result..

The settings window will only let me set 1 date (the start date is greyed out)

try as I might i cant get it to display a sinle day of sun over the landscape

Ive had to resort to drawing paths to try and get an idea of sun activity east to west but obviously this doesnt come close to what the sun really does in summer

Same problem earlier Freda, also I accidentally got stuck in star mode? confused the hell out of me xD

To look at the suns path on a specific day you have to do this....

Open up google earth, go to your're desired location, go to ground level, (zoom in as far as you can)when you hit ground level view it will display it in the top right hand corner.

Now look at the 13 tabs along the top, there should be a tab with a sun above a cloud (it's between a tab that looks like a clock and a planet that looks like saturn) select the sun above the cloud tab and make sure no other tabs are highlighted (the background of the tab will be highlighted blue, when active)

Now you should be able to look at the suns path throughout the day, but the time of year will need to be changed.

You can do this by going to the slider (in the top left hand corner), on the slider there should be a spanner (in the top right of the slider), this is where you set the time of year you want to view the suns path. Once you have set the time of year click OK, now adjust the slider back and forth, this will now show you the time of day and the suns path. Remember when your in ground level view you will have to look up and follow the sun manually (which can feel awkward at first)

Hope this helps

Pierre

[ST0N3R S1MPS0N]

Is there another link to the 'Other Places.kmz'? I cant seem to find it?

[ST0N3R S1MPS0N]

Should of read the rest of the feed! Top work Weed G thanks for that mate! Happy Growing!

[drops boms]

Just google

Gavins unofficial os map overlay

Or

Gavin kmz

Thats what I did then as soon as it downloads its in googe earth

Hope it helps

Ill put the exact link in tonight

....Drops

[ravsta]

Google and OS side by side

http://wtp2.appspot.com/wheresthepath.htm