Monday, June 26, 2006
Overplot mashes quotes heard in New York
The technical details include having to use an overlay instead of individual pushpins, since there are so many clustered results to show, and the use of the canvas object to draw areas. Although there is a fallback to ExplorerCanvas to support IE, the code makes no allowances for earlier Mozilla browsers that didn't support the canvas object, which is a shame, since it looks as if this was a late change to improve performance - presumably the earlier code could have been left in place (with reduced performance) to cover a fuller range of browsers.
Sunday, June 25, 2006
Geoportail - impressions of the homepage
- The site is all in French! OK, so thats the political reality of this being set up by French government dictact, but if the objective is to encourage interest in France and French culture, then making it more accessible to those outside the country, speaking different languages, would seem to be a valuable feature. (The site is also (un)available at geoportail.com, but this just redirects to geoportail.fr)
- There are 3 stages outlined
- Summer 2006 (now) - aerial images and scanned maps
- Autumn 2006 - 3D viewer, and initial data sets
- 2007 - a rich set of public information available, plus WebServices
- The page is hardcoded for a screen size of 1024x768 - if you have a smaller screen then there's a lot of scrolling needed, and a larger one wont give anymore useful info. This is not the way to handle such graphically rich applications as mapping - they really do need to use all available screen space to show as large a map as possible. The layout is achieved via tables, rather than via CSS.
- Coverage entends to
- ST MARTIN
- ST BARTHELEMY
- ST PIERRE ET MIQUELON
- NOUVELLE CALEDONIE
- ILES KERGUELEN
- ILES CROZET
- The initial map shows the whole globe - with no zooming or other controls on it. If you move the mouse over the map, certain hidden areas are clickable - merely indicated by the mouse pointer changing to a hand pointer. (These areas are of course those listed above).
- There's a built in feature for bookmarking favourite locations. The current top 3 are
- Le Terminal Trans-Manche (62)
- Le Mont-Saint-Michel (50)
- Le Château de Chambord (41)
- The geoportail site is for the "visualisation"; there is a separate site for the "geocatalogue" (and this site, since it has nothing but a holding page until Sept 2006, is available). The visualisation does not include any search box, to direct the map to a particular location.
- In a commendable effort to be openly available to as many users as possible, the site is
- Much of the site is using php to serve up the pages, even for what would appear to be static information - perhaps that's part of the problem as to why the servers cant cope with the demand.
compatible with IE6 and greater, Mozilla 1.7 and greater, Firefox 1.0 and greater, Safari 2.0 and greater, and OSs Windows 2000, XP, Linux (Redhat, Suse, Debian), Mac OS X
Friday, June 23, 2006
French support of Google Earth
There they have some very well crafted KML files, which show information about the interior region of France, to the west of Toulouse. The files on offer include both sets of placemarks, and also presentation of statistics such as employment and population figures. Neat features about the KML used include snippet control, the addition of a fixed logo, and a copyright string down the left of the view, though unfortunately the statistics key now appears just where the (semi-transparent) controls of Google Earth 4 are.
It looks as if the data files were prepared with the help of GE-Data, a French company which specializes in producing data files for Google Earth.
... and as for geoportail itself, as I write this, the website is unavailable, so all we have to go on are some screenshots and early user reports.
GNT, a French tech blog, has coverage of the inaccessibilty of geoportail, IGN (which produced it), and of GNT itself, which happened to also rank highly in Google for the search "geoportail". The screenshot included in this report is quite unlike the others - I assume it is from an earlier prototype of the site.
Thursday, June 22, 2006
Opera 9 ships, but still fails in its support of xml
Although web browsers are primarily used to browse HTML formatted documents, they can also be used to view a number of other types of documents. Foremost amongst these are xml documents, a close relative of HTML documents, but in many ways far more powerful - that x stands for Extensible. Viewing a raw xml file is rarely the best way to do it, so xml files are generally viewed with the aid of a stylesheet - written in xsl (Extensible Stylesheet Language), and the the process of transforming the xml into a viewable form is known as XSLT.
The Opera 9 spec document states that
It sounds from that as if the support of xml is pretty extensive, but in practice there's aparently a lot of flexibility in those words. The "near-complete support of XSLT 1.0" seems to mean that they don't support the vitally important document() function - which rather takes the teeth out of XSLT. The document() function reads xml from a named document URL, making the XSLT process powerful, allowing it to pull information in from a number of xml documents. Consider a page of product information that pulls in current prices from a specific price document, and stock levels from another document.
Opera can parse and display XML documents. Opera can be both a validating and non-validating processor.
Documents with Content-type "text/xml", "application/xml" or with a subtype ending on "+xml" will be treated as an XML document. If a Content-type is not available, the ".xml" file extension will also make the document be treated as XML. Opera does not use US-ASCII as the default character set for
text/xml, but otherwise follows RFC3023. We recommend using
text/xmlor use explicit character set declaration.
XSLT, XPath, and XSL-FO
Opera has near-complete support of XSLT 1.0 and XPath 1.0
Opera does not support XSL Formatting Objects.
(The previous version, Opera 8, had no support of XSLT, so partial support might sometimes be considered an improvement. However, in many cases its a step backwards - in Opera 8, since the XSLT instructions associated with a xml file are ignored, at least you get to see the raw xml data. In Opera 9, it starts to process the file, but fails on an unsupported base feature, so nothing but an error message is displayed).
Without fully supporting XSLT 1.0, Opera languishes a long way behind the other browsers in supporting xml - IE 6 has great support for XSLT, as does the Mozilla / Firefox family (if a little slow at times).
Update: A fascinating interview on Slashdot, with Håkon Wium Lie of Opera. He notes that:
From that perspective, it makes sense to leave ### half-implemented. You can claim support (and many journalists will believe you), and you also ensure that no-one can use the unimplemented (or worse: buggily implemented) features of the standard. The only way to change the equation is to remind ### how embarrassing it is to offer a sub-standard browser. And to use better browsers.How true this is - the sentence could so easily apply be completed with XSLT and Opera filling in the gaps. Actually, the published quote was about CSS2 and Microsoft!
Håkon Wium Lie was the father of CSS, and I think reading the whole article gives an insight into the thinking at Opera - they view CSS as all important, and are happy to let XML and XSLT take a back seat. This also comes through across in another reply, which notes
... CSS is an intrinsic component of AJAX. The "AJAX" name sounds great, but allow me to propose a few alternate spellings that I find more accurate:
Wednesday, June 21, 2006
Bloglines upgrades their Atom parser
However, in "Duplicates; real and imagined" it mentions that it is introducing a new Atom parser, and the Atom protocol makes it much easier to detect duplicates, especially when articles are syndicated into different feeds.
It looks like this parser is available now - so now I can read Tim Bray's Ongoing in its full text form, rather than in just the summary form that he also made available in RSS format. (Looking at the stats from Bloglines, I see that Tim has 49 Bloglines subscribers for his Atom feed, but 3465 via his RSS feed - expect that pattern to change now that the much better Atom feed can be displayed properly).
Tuesday, June 20, 2006
An API for Picasa?
Specifically, Picasa offers the following
- upload to a Web Album (new in the Picasa 2.5 beta version)
- upload to Joga (in the customized version of Picasa available at Joga.com)
- upload to Blogger
"we had to spend a couple of days reverse-engineering a complicated desktop application/server-based protocol, then more time debugging it, and as of late, more time bringing it up to date for the 2.5 release of Picasa."Picasa has some other potentially useful integration points
- the oem.xml file is used by the Joga customized variant to supply the customization of the title bar
- Picasa 2.5 uses kml files to interact with Google Earth, with the communication in the reverse direction acomplished by Picasa acting as a web server
- Picasa also shows a webserver interface when you use the Ctrl-L shortcut, which gives a close approximation to the Picasa UI within a web browser
- Picasa Web Albums offer a "download to Picasa" link that works by using a url of the form "picasa://downloadfeed/?url=http%3A%2F%2Fpicasaweb.google.com%2Flh%2FrssAlbum" so Picasa must register a url handler for the "picasa://" protocol.
Thursday, June 15, 2006
Keyboard shortcuts in Picasa
However, its documentation is a bit sparse, and hard to find (and from a developers point of view it's one of the few Google offerings without an API).
Certainly underdocumented are the many keyboard shortcuts that the program offers, which both serve to make using the program easier and faster, and in some cases offer facilities that are not available with the mouse, or via the menus.
My favourites are:
- CTRL + ALT - displays the image the mouse is over at full screen size
- CTRL L - brings up a web browser view of the whole Picasa interface
- Google's official list of keyboard controls for Picasa
- An expanded unofficial list helpfully given in alphabetical order
Tuesday, June 13, 2006
Google Book Search - Shakespeare
A sidebar on the page suggests "Take a Literary Field Trip - Download Google Earth to visit the Globe Theater and other Shakespearean landmarks right from your desktop.", but unfortunately it doesn't provide a KML file link on the page to actually provide this tour.
There is also no actual search box on the page, so although you can browse through the various Shakespearean plays by title, you cant do a simple search for a word, or half remembered piece of dialog - surely some mistake from a search engine!
Major mapping upgrades from Google
- Version 4 (beta) of Google Earth, which is now available for Windows, Mac, and Linux. This has an improved UI that give lots more space to the photo data, and allows textured 3D models
- A new version of the KML file format, that supports the new 3D model changes, improves network links, adds regions for different details at different zoom levels, adds radio buttons
- A new version of SketchUp, now available for Windows and Mac, that produces textured 3D models
- Geocoding in the Google Maps API - available for US, Canada, France, Germany, Italy, Spain and Japan, with data returned as xml, kml, or JSON
- Support for KML in Google Maps
- why no UK geocoding suport? - Google claim that "More countries will be added as Google Maps launches in new countries", but the UK was the first country after the USA to get comprehensive Google Maps coverage
- Supporting KML for Google Maps as well as Google Earth is great, but it looks as if the Maps version is severely limited - for example loading my Countries of the World KML file gives corrupted balloons, just 67 data points, and a message that "Parts ... could not be displayed because it is too large"
Sony SLR digital camera
Its an obvious development of the Konica Minolta 5D, using the Minolta lens mount, and so compatible with many existing lenses. The highlights of the camera include
- 10 megapixel CCD
- camera integrated anti shake
- anti dust mechanism
- 40 segment honeycomb metering
- 2.5" 230,000 pixel LCD monitor
- Lithium ion battery with a claimed capacity of 750 shots