Wednesday, July 27, 2005


Space Shuttle, and other maps

More worthwhile mapping mashups and resources:

Tuesday, July 26, 2005


Improving the UI of mapping sites using CSS

When run in Mozilla/Firefox, MSN Virtual Earth does not have quite the same visual appearance as it does in Internet Explorer - specifically the banner header holding the search controls at the top of the screen is solid in Mozilla, but is semi-transparent on IE.

I realized that this could be fixed by a simple change to the CSS. Whilst I was at it, I went further to see what else I could improve in the Virtual Earth UI, using just CSS. The changes I put in my CSS file for Virtual Earth are:
I also made a similar CSS file for Google Maps, which gives a similar set of improvements:
These CSS files can be used in Mozilla by using the "Add User Style Sheet..." option in the Web Developer toolbar.

Update: 5th Oct 2005: There is a new layout to Google Maps that means this CSS file no longer works. I'll have to see if I can find time to fix it for the new layout.

Update: 6/10/05 I've updated the CSS file now.

Sunday, July 24, 2005


VirtualEarth from MSN

MSN have launched Virtual Earth - their attempt to catch up with Google Maps.

Having tried it out for a few hours, I think they've generally missed. There are a few areas where they exceed the capabilities of Google Maps, but these are outweighed by those where they fall short.

The capability that is likely to get the most press is the fact that they show the USGS colour data at full resolution (ie at the resolution that Google Earth uses, not the reduced resolution that Google Maps currently displays). However, outside of the USGS colour areas (around 30+ US cities), they only show the black and white USGS data - which is a very poor substitute for the sometimes lower resolution, but coloured photos that Google uses. Google also has detailed coverage for many cities throughout the world, whereas Virtual Earth is limited to detailed data in the USA only.

A possible other reason to prefer VirtualEarth is it has a larger part of the screen given over to the map, since it does not reserve space alongside the map for search results.

The list of areas they fall short of Google Maps is longer:
Virtual Earth comes with what they call an API - which simply means that they have documented the URL format used to bring up a page at a specific location and zoom level etc. Unfortunately the URLs use the pipe character "|" when constructing the URLs - I've always considered this an invalid character (though the RFC may be ambiguous in this respect), and I know of plenty of tools which will not cope with such URLs - wikis for example, which often use the pipe character to separate a URL from the label a link will use. It's worth noting that its possible to separate the latitude from the longitude in the URL using a comma instead of the pipe character, but they really need to remove the pipe character altogether.

Saturday, July 23, 2005


Hybrid mode for Google Maps

Google Maps has gained a hybrid mode, which overlays mapping data on top of the satellite images. To achieve this, they have had to rescale their photographic images, which were not to the same scale as the maps. This appears to have been done by resampling the existing images, so for example the Google copyright watermarks have been stretched along with the rest of the images.

In most cases the maps and the images line up well - though as always people take great pleasure in finding the exceptions. A discussion on Slashdot found the following examples:

Monday, July 18, 2005


Update to Yahoo Maps API to allow POSTING

Whilst I'm unconvinced of the general usefulness of the Yahoo maps API (since the maps cannot be integrated or otherwise embedded into other pages), they have just made them potentially a bit more useful.

The original API took a URL that supplied the RSS feed describing the map points. This URL therefore had to be accessible to Yahoo's servers - thus ruling out use on intranet sites, and on many sites where the data could not easily be written to a file.

The changed API allows the data to be supplied directly via the API, in the form of an HTTP POST. Details in a new POST section on the API documentation page.


Google Maps showing a scale

Google Maps have started to show a scale on their maps, in the position previously used by the Google logo.

This scale does not always appear on the maps, but does seem to be there whenever you go to a map via a "link to this page" URL. The scale is provided with the tooltip "Scale at the center of the map" and gives a horizontal scale. As you scroll the map, the scale changes dynamically as the area in the center of the map changes, which dramatically illustrates the fact that the scale is not constant over the whole of the visible map. No attempt is made to provide a scale in the vertical direction, which is not normally the same as the horizontal one.

The scale is shown for both the maps view, and the satellite view, and gives both imperial and metric units (with the unit changing as appropriate to keen the numbers managable).

I've not been able to determine if there is a way for applications using the Google Maps API to get to show this scale.

Update: Its not been documented yet, but the API now supports the Scale control via a command such as:
map.addControl(new GScaleControl());

Friday, July 15, 2005


Nuclear blasts on Google Maps

Eric Meyer has produced an interesting, if slightly bugged application of Google Maps with his HYDESim maps which are an indicator of structural damage to buildings from a nuclear blast.

The maps show rings of overpressure caused by the blast - which is unfortunately where they go wrong. Google Maps do not have the same scale both vertically and horizontally, so these rings should really be ellipses. The error is not too bad in much of the mid-USA, but moving further North or South the errors mount up, and switching to satellite mode the difference can be even greater. For example at -96.24298095703125, 63.87451171875 on the satellite image the ratio between the vertical and horizontal scales is roughly 23:10.

Thursday, July 14, 2005


Pixsy - the random image search engine

Pixsy is a new image search engine that "searches blogs, mobile blogs ("moblogs"), social networks, and other sites that have unique content" in order to find images that most search engines miss.

That's all very well, but unfortunately viewing any of the results seems to be a lottery. Like most engines, it does not show all the results on one page, but offers Next and Previous links. The URL of a results page is currently - note that it has a parameter of next, that steps you through the groups of results each time you get to that page. Thus the standard operation of "view an image then press back to get back to the results page" does not take you to the same results page, but instead advances you to a new set of results.

Even on a single page of results, the details links are always numbered from zero for the first visible image, (so the first image on the first page and that on the second page etc all have the same URL), so it seems to be random when you view the detailed image result as to whether you will get the image you thought you would, or rather some other image that shares the same URL on a different page of results.

Wednesday, July 06, 2005


Weather maps of the USA

It may not last long at this URL (which is just a development one), but Weather Maps is presenting Weather Underground information on Google Maps.

The markers for each point artfully show all of temperature, wind strength and direction, and weather observation, and the popup info window adds humidity and a temperature chart.

There are also links to webcams so you can see the realtime weather, and data can be downloaded for display in Google Earth.

Update: More weather presented on maps at:

Tuesday, July 05, 2005


Roundup of more mapping highlights

Google MapsGoogle Earth

Monday, July 04, 2005


Official Google toolbar for Firefox on its way

Fritz Schneider has contacted the Googlebar developers to let them know that Google are expecting to release an official Google Toolbar for Firefox this week.

It will work with Firefox 1.0+, on Win2k/XP, MacOS X 10.2, and Linux 8.0+. With the exception of the popup blocker (which Firefox already has), it will match the features of the latest IE toolbar. Thus we can expect spellcheck, autolink functionality, and probably a PageRank display.

For a while now, if you visited the Google toolbar page using Firefox, it suggested that you install the independently developed Googlebar thus:
Googlebar: We encourage Firefox, Mozilla, and Netscape® 7.x users to install the open-source Googlebar, developed and supported by Google fans.

Saturday, July 02, 2005


Google Earth feeds and files

Google Earth is the downloadable application from Google that uses the same satellite data as Google Maps, but which literally takes it into another dimension. The images can be scrolled as with Google Maps, but can also be viewed from an angle and rotated - and since the data is augmented with altitude data, some of these views can be most spectacular.

[The downloads page has been temporarily disabled, whilst Google increase capacity of their servers]. The free entry level version of the application runs on Windows, but the enterprise version runs on Linux.

Data for overlaying the images with points of interest is stored in KML files. Google have put together documentation for the KML file format so that other people can produce these files.

You can search via Google for kml files (and their compressed kmz equivalent), though beware that these will also bring up some non-google earth kml files.
Specific feeds of interest include:

More static files of interest include: - visual effects, and drag-and-drop framework is a javascript framework which provides (currently) a number of visual effects, and drag-and-drop support. It's available for use under an MIT style licence.

There's an example puzzle, to illustrate the drag-and-drop, that although very simple is quite entertaining.


More Google Maps API applications

Google Maps API applications are coming thick and fast now. A few that caught my eye:


Lengthfinder - Google Maps based app for measuring distances

LengthFinder is a Google Maps based page that allows you to interactively plot a path on a map, and display the length of that route.

The developer is Australian, so the map (or actually satellite image) comes up centred on Sydney, and distances are given in Km only. There is also a conversion to walking/cycling time - I guess they walk slow in the Australian heat since the conversion assumes just 4Km per hour walking pace!

Friday, July 01, 2005


Another maps web service is another site which aims to simplify using the Google Maps API, by simply serving up a map as a web service.

It also supports geocoding of locations, and is designed to be placed in a iframe.


Greasemonkey script to add Google Map to any page

Greasemap is a Greasemonkey script which adds a Google map to a page if it finds any geocodable addresses or other geotags on the page.

The map is placed in an iframe served up from - which gets around the restrictions that the Google maps key registration mechanism imposes.

Currently recognised locations are of the form
The actual script is very short - it simply packages up any geotags on the page, together with any addresses recognised by a regular expression, and then passes it via a URL to the server which produces the iframe contents to be placed in an injected iframe tag.

All geocoding of addresses is done on the server. The server is thus a useful webservice in its own right. Take a look at:,Seattle,WA

- it produces a twin map layout, showing a wide angle view, and a close-up.