December 28, 2006

worldKit 3.1

I'm taking advantage of a little quiet in the interholiday to bring the worldKit distribution and documentation up to date. There's a bunch of small new features, some sponsored by MetaCarta, and a few experiments since the summer.

FP 8

The biggest change is that Flash Player 8 is now the required minimum version. Penetration is now high enough to do this safely. It fixes some bugs in the javascript communication (the ExternalInterface class), and allows worldKit to work with PNGs and GIFs. And it greatly simplifies support. Hopefully this will be relatively painless for everyone.

Look and Feel

In the toolbar, there are two new icons to switch between zoom (rubber band zoom) and pan modes. The config options "zoomselect" and "grabber" now simply set the default mode.

When in annotation mode, the cursor is replaced by a small crosshairs icon.

And worldKit now responds to the Mouse Wheel, by zooming in or out.


MediaRSS is now the preferred namespace for using images in worldKit. It's widely supported and a "mature" standard (as mature as a web standard can get these days). media:content is for specifying images in GeoRSS, and media:icon for specifying the annotation icon.

In addition to the recent update of the docs to GeoRSS, the "Box" geometry is also now supported.

New RSS Config Options

  • <fade> Specifies a number seconds for an annotation to fade to transparent. Useful for visualizing transient information. The default value is "-1", which means no fade.

  • <rssbbox> Set to "true", the bounding box of the current view is appended to the RSS feed url. url&bbox=WEST,SOUTH,EAST,NORTH. This is useful for displaying only part of a large data set. Default value is "false".

New Javascript Communication

Even more integration with Javascript. The amount of functionality here is getting complex .. I expect all these "APIs" could use some rationalization in the future.

worldKit -> JS: <onzoompan>, <fadeditemcallback>, and <newitemcallback> are configuration options for specifying javascript callbacks to these events.

JS -> worldkit: JItemActComm, JNavmodeComm, and JGetExtentComm are new functions available to javascript.

TileMap and WMS

Tiling schemes for map data sources is a hot topic among open source geo developers. Tiling speeds up access to WMS dramatically. worldKit already supports tilings schemes for OnEarth. Tile Map Service is a specification under active development, and worldKit now supports the global geodetic profile. More information in the docs.

Also, <wms now accepts "minview" and "maxview" optional attributes, for setting the viewable range of a WMS.

That's It!

Do get in touch with any comments, suggestions or bug reports.

Posted by Mikel at December 28, 2006 03:46 PM