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Google Earth Pro print options advanced formating

When Google Earth Pro was first made available for free we had a look at the advanced printing options in Google Earth Pro that are not found in the standard version.

We recently had an enquiry from a GEB reader about how to change the background colour of the Title element. This YouTube video from Google gives some idea about what is possible and points out that the HTML Area element can contain just about anything that can be done with HTML, including an external website. However, it doesn’t mention that the Title and Legend elements can also be styled with HTML and CSS.

If you want a fancy title, one easy solution is to simply turn off the title element and use the HTML Area element instead, as that is easier to work with. However, if you want more than one section of text on your map you may find it easier to use both.

To change the background colour or transparency of the Title element, have a look at the contents of the HTML Area element element to get an idea of how it works there. The HTML Area element has a DIV with an id of ‘white_box’. It turns out that both the Title and the Legend boxes also have an identical DIV.

So for example, if you want to get rid of the background in the Title element simply edit the element and paste the following text anywhere. We recommend putting it at the end of the description for neatness.

<style>#white_box{background:none}h1{color:white}p{color:white}</style>

The above also changes the heading and description to white to make them more visible and to produce high quality materials. Note that the heading can be styled with the H1 tag and the description using the P tag.

The Legend element works exactly the same way – simply paste the above or your own styles into any of the legend entries.

Unfortunately, it seem that CSS gradients are not supported.

If you spend a long time working on the print settings be sure to save them, as they will otherwise be lost when you exit Google Earth Pro.

The above Title was formatted by adding the following text to the description:

<style>#white_box {background-color: #a2d7d8;border:5px #fcd059 solid;border-radius:20px}h1{color:#de5842;text-align:center}p{color:black;text-align:center;font-style:italic;font-weight:bold}</style>

Correcting map data – placemarks

Back in July last year we wrote a Google Earth Blog FAQ to try and answer some of the most common questions we receive via email. One of the questions we answered was about making corrections to mapping data. This post is intended to be a more detailed look at how to get corrections made to mapping data. In this post we will look specifically at the placemarks and even more specifically the easiest ways to update placemarks. In later posts we will look at other ways to update placemarks and other types of mapping data such as roads, road names and addresses and borders.

The first thing to note is that the primary source of mapping data is Google Maps. This data is replicated from Google Maps to Google Earth somewhat infrequently. So, the first thing to do when you notice an error in a Google Earth placemark is to find it in Google Maps and check whether or not it has already been corrected in Maps. If it has been corrected then you don’t need to do anything further and it should get replicated to Google Earth at some point.

The first step in correcting placemark errors is to open Google Maps and either click on the placemark or search for it in the search bar. The place should then be opened in the side bar on the left as seen below:

  1. The placemark is incorrectly placed in the centre of a crossroads.
  2. Clicking on the placemark or searching for it in the search bar opens it in the side panel.
  3. Click “Suggest an edit” in the side panel.

We found that in some countries (Zambia, for example) the “Suggest an edit” link is not shown. We believe that this is because Zambia does not yet have a Regional Lead for the Google Map Maker program. We will discuss Map Maker more in a later post. If you do not see the “Suggest an edit” link in your area then there is not a lot you can do to correct map data at this time unless you are willing to put in a lot of effort and get involved in the Map Maker program.

When you click “Suggest an edit” you should now see the “Report a data problem” window as seen below.

There are three main types of errors you may wish to fix: a misplaced placemark, incorrect information about the place, or a placemark that shouldn’t be there at all, such as a business that has closed down or a duplicate placemark. The first step for all three types of corrections is

Misplaced placemark: Simply drag and drop the placemark to the correct location. You may also wish to update the address as well, which you can do by simply clicking on the address then typing in the correct address. When done, click submit.

Incorrect information: Simply click on the information you wish to update and fill in the correct information. When done, click submit.

Removing a placemark: Click the button at the top where it says “Place is permanently closed or doesn’t exist”. You will then be given the option to say whether it is permanently closed, doesn’t exist, spam, private, moved elsewhere or a duplicate. Select the appropriate option and click submit.

The actual updates are managed via Google Map Maker. For most edits this will require someone from the Map Maker community or a Google employee to review your edit before it is published, so expect a few days before your edits show on the map. It may take significantly longer for the edits to show in Google Earth, depending on the type of edit. Some information in Google Earth, such as what shows in the popups, is essential live Google Maps data, whereas the locations of placemarks is not live and may take a lot longer to update.

Explore Mars in Google Earth

This has been a big week for Mars with the new NASA discovery of flowing water on the red planet, and the release of a blockbuster movie “The Martian” based on the New York Times best seller of the same name by Andy Weir and starring Matt Damon. An excellent book by the way! So, this is a good time to remind everyone that Google Earth also can portray Mars just like it does for the Earth. Mars in Google Earth has a fantastic archive of data from NASA (and other sources) from orbital imaging platforms, and Mars landers including 3D terrain, global imagery, high resolution orbital imagery, lander photos, and even lander 360 panoramas. The lander locations and tracks can be viewed, as well as their last known positions. Most of the data is current showing even the latest position of Curiosity and Opportunity. Mars for Google Earth only works in the desktop application (not on Google Earth for mobile).

Mars option in Google Earth 5

To get started, you simply look for the little planet icon at the top center of Google Earth and click on it for a list of options including Mars (you’ll see there are also versions for Sky and Moon). Click on Mars, and the Earth globe will turn into Mars. Mars was released in February 2009 (see original Mars review).

See below for my original video review of what Mars for Google Earth is really like:

You can spend hours exploring Mars and the layers Google created to explore the data from the various landers and orbiters. I especially enjoy the panoramas by Opportunity and Curiosity. An important tip if you want to explore the panoramas is that you might need to expand the time slider selectors that appear in the upper left so they show the full time span. Otherwise the panoramas may load up invisible until you find the time when it was taken.

And here’s a cool trick even long-time users of Google Earth might not have discovered. Fans know that Google Earth has a built-in flight simulator (read more), well you can also use the flight simulator on Mars! Kind a fun to fly around the crater at the top of Mons Olympus, or through the huge canyon of Valleris Maneris. Just look for the menu choice “View->Flight Simulator”. I recommend the F-16 for faster flying. You’ll need to learn the flight simulator a bit to fly well. Here’s a view of flying on Mars.

Flying on Mars
Flying on Mars

I’m planning to see the movie this weekend. Can’t wait to see it!

Geocoding with Google Earth Pro Import

When Google Earth Pro was made available for free earlier this year we showed you that it could import addresses to Placemarks. However, what may not have been so obvious is that the geocoding that it does works equally well with locations such as suburbs, cities or even countries.

To demonstrate how it works we chose three lists from Wikipedia.

The first is a list of countries and dependencies by area. The first step was to copy the data into Microsoft Excel and clean it up a bit. We decided to keep only the figures for the total area in square kilometres. We then saved the data as a csv file and imported it into Google Earth. There were 47 countries or dependencies that Google Earth failed to geocode on the first try. We managed to resolve some of the dependencies by removing the country name which was in brackets.

Strangely enough there were still 18 entries that failed:

We also noted that in the resulting KML, many of the Placemarks do not match the exact locations of country names as seen in Google Earth although, the ones we checked were at least in the correct countries.

It is also possible to colour code the Placemarks based on the figures in one of the columns, but we found that it didn’t really work well for this particular dataset, as the large area of Russia in relation to all the others caused the colour scale to be ineffective and the Placemarks are not really large enough to see the effect on the map.

The second is a list of the cities of Japan. We used the English name column as the Japanese characters would have posed some challenges. Google Earth Pro failed to geocode 125 of the 812 cities in the list. We tested some of the failed entries by searching in Google Maps and it was able to find them without any problem.


Japanese Cities according to Wikipedia. The colour of the icon reflects population density, and the height reflects population.

The third is a list of Cape Town Suburbs. To help with the geocoding we added the city and country to a column in Excel. On the first attempt, it failed to geocode 17 of the 125 suburbs. 7 were easily repaired by removing alternate names listed in brackets. However, there were still 10 suburbs that it failed to geocode. We tried searching for them in Google Maps and some were correctly found in Google Maps, while some where not.


Suburbs of Cape Town with Post Codes in the popups.

Notes:

  • It appears Google Earth Pro is not using Google maps data for geocoding.

  • When Google Earth Pro fails to geocode some location and you proceed without correcting them, they are all given the coordinates 0° latitude 0° longitude. You can then, if you wish, manually relocate them.

  • What we did not do for any of the above lists was to check whether the locations were accurate.

  • The geocoding returns just a Placemark with its latitude and longitude. A search for countries, cities or suburbs in Google Maps outlines the geographic area. Having a geocoding service that similarly returns the region for display in Google Earth would be very useful.

Overall, it looks like a useful service, however, if you find that there are a large number of failures, as we did for Japan, you may wish to search the web for alternative geocoding services and then import the data after the geocoding is already done.

To view the above datasets in Google Earth download this KML file.

The Google Earth cache

The Google Earth cache not only provides significant performance benefits but also allows Google Earth to be used offline. For more on how to do this, see this post by Frank.

The cache settings can be found in Tools->Options->Cache. A common complaint by Google Earth users is that the maximum sizes have not been increased for a long time and thus seem somewhat small for todays computers. Currently the maximum disk cache size is 2048 MB and the maximum memory cache size is 1024 MB. If you have sufficient memory and hard disk space then set them to their maximum.

The default location of the cache in Windows is in %AppData%\LocalLow\Google\GoogleEarth, but it is possible to move it to the location of your choice by modifying the registry setting HKEY_CURRENT_USER\Software\Google\Google Earth\CachePath for the standard version and HKEY_CURRENT_USER\Software\Google\Google Earth Pro\CachePath for Google Earth Pro. Since mechanical hard disks are often the slowest part of a modern computer you should experience some performance gains by putting the cache on an SSD if you have one or even a USB 3 memory stick.

We found while using the Google Earth plugin to map historical imagery density that the Google Earth cache filled up about 700mb for each 5 x 5 degree square of the earth. That figure is just approximate, as the area covered by 5 degrees of longitude varies considerably by latitude, and how much the cache gets filled varies depending on what zoom you are at in Google Earth. In addition, we were in ‘historical imagery’ mode, which loads significantly more imagery than the default view. Nevertheless, it demonstrates that caching a whole continent at high resolution is impossible within the current 2 GB limit.

We also discovered that the Google Earth plugin creates its own cache rather than reusing the Google Earth cache. In addition, having multiple instances of the Google Earth plugin open results in multiple caches being created. In our case the total cache folder ended up growing to well over 8GB.