Map Tales vs Google Earth Tours

Over at my other blog there's a post comparing Google Earth Tours with a web service offering similar functionality.

Misleading BBC Landscape Animation

This is a lovely science story:  A massive range of mountains completely covered by the Antarctic ice sheet has been mapped in 3D detail.  The story is nicely explained in an animation similar to a Google Earth Tour.

Unfortunately it contains a visualization howler:  The vertical exaggeration is about x200 and although this is marked on the above diagram, it isn't emphasized (the 4000m scale bar is off in a corner).  When you play the animation, it gets worse, you aren't told about the exaggeration at all.  The outcome is that untrained viewers of this visualisation will think that under the ice the topography is much steeper than the Himalayas whereas I estimate the steepest slope they have visualized is no more than 1:500.

Flood London's Bankers!

I was recently asked to produce something to showcase new big screened computers in a new media room at Southampton University.  VIPs watching including our Vice-Chancellor.  I revisited an earlier idea where I flooded London, I rewrote the code using an animated update to produce a tour which will raise the water from 20 to 200m in 3 seconds.

Open this

Flood London.kmz

and turn off all layers in the layers panel except 3D buildings which should be on.

1] Double click 'Space to High' and you will be flown from space to a high view over london.
2] Double click 'Flood London' and sea level rises from 20m above current to 200m
3] Double click 'High to City' to be flown to the city of London.  You should see the skyscrapers of London's banking center already partly flooded.  Turn off the tour (black cross in tour control, bottom left of main screen) then
4] Double click 'Flood London' and the sea rises again.  Experiment with controlling the tour controller bottom right to see you can become a virtual Canute. 

It shows two nice teaching facilities:

• Animated update which will require you to get into KML if you want to do it for yourself in another location.  
• A set of tours:  By combining tours which fly the user around with one which controls the flood level we can build some interesting visualisations.

Google Earth vs Web Maps for Education

As I said over at my new blog, I still think GEarth more useful for education than other web maps systems. Frank Taylor commented that I should note that here, I think he makes a good point and that it deserves a post.

Creating maps via the web is now wonderfully simple either by web maps or virtual globes (Google Earth, OSM, Google Maps, GeoCommons) when compared with traditional GIS.  This opens all sorts of opportunities for educational development that haven't previously existed.  However, I think GEarth is still the best tool for education because it has features that web maps lack:

• Tours:  Google Earth Tours allow educators to pre record flights around the globe either to be used as a replacement for powerpoint or for use in a class activity where students see a tour then practise a skill.  Tours functionality is only available in ESRI's virtual globe apart from Google Earth.
• Offline:  You can cache imagery, load maps and create maps all offline with Google Earth.  That has considerable advantages for many uses in education.
• 3D:  When looking at cities (3D buildings) and landscapes where terrain is important the 3D aspect of Google Earth becomes important.
• Others:  Other advantages include the transect tool, great usability, a wealth of KML files on the web that can be customized for educational use and the fact that many students are used to the basic GEarth controls.

GIS for Schools:  I've always said that in schools visualization is the important feature of a computer mapping system, the analysis that comes with GIS is just too complex to teach at school level, its more than enough to get students used to concepts such as symbolisation, choropleths, layers, rasters, vectors, zooming and panning.  So the fact that GEarth can be used to teach all these concepts is more than enough, spending money buying anything extra is not worth it IMHO.

I'll be continuing to discuss GEarth in education here.

New Blog!

Welcome back, before I left I promised an announcement.  As of today I'm switching the majority of my blog writing to a new blog:  Web Map Design.  Check out the welcome message to see what this means for this blog and my reasons for the switch.  I've also already written posts over there on Google's London Transport Map, and Goldilocks Maps.

Blog Holiday

Today's was the last post until September - I'm taking some holiday and I also need to focus on some other projects.  Do check back after August is over as I have something exciting in development to announce.

Navigation - Too much freedom?

I'm currently writing a paper about the use of GEarth Tours in education.  I thought I'd discuss one aspect that's come up: the problems of navigation in 3D software (thats Maps as well as GEarth as you effectively move through 3D space using pan and zoom).

The Problem: In GEarth you have 5 degrees of freedom:
  Altitude, Latitude, Longitude, Camera Pitch, Camera direction

Controlling these is complex and so causes problems - users can:

• become lost in virtual space
• get disorientated 
• become confused as they fly through model walls (ie inside a building only designed to be seen from outside)
• navigate around missing the views that the designer of a GEarth project wanted them to see.

As you may imagine any combination of these leads to the same result:  users become disheartened and leave to go and look at something else.

Similar Problems in other Software:  It isn't just GEarth - map systems, information spaces with pan and zoom functionality and Virtual Worlds all suffer from similar problems.  In some software its possible to fly straight into the ground with nothing visible at all which is when you get 'desert fog', users don't know where they are with no visual clues on screen to help them.

Solutions:  There are multiple solutions I've found in the literature, one is illustrated by Google Body:  Constraining freedoms of movement from 5 to 2.  When viewing the body your camera angle is fixed and you can only fly around a cylinder of fixed distance from the body (in fact it feels more like you are moving the body rather than your camear position but actually they add up to the same thing).  

GEarth Tours:  The solution readily available in GEarth is the GEarth tour, effectively you are constraining the user to 1 degree of freedom as within a tour they only have the ability to play or rewind  - nothing else.  This means that providing the tour is designed well we mitigate or solve all the problems I listed above.  

In education removing those issues comes at a cost:  users watching a tour are far more passive than if they are navigating around so we have to be careful to insert active tasks into tour.  For example, turning the tour off for a while and having students go and search for a landscape linked to the GEarth tour they've just viewed.  How to do this is the theory that we are investigating with our Google Research Award.