November 2006

Open jACOB Draw2D

Andreas Herz has added diagramming features (connectors, ports, tool selection) on top of Walter Zorn's famous DHTML graphics library to create Open jACOB Draw2D. There are several interactive demos that let you create simple diagrams. There is also javadoc style documentation (though it mostly documents the class hierarchy).

I think a discussion of the underlying wz_jsgraphics library (which currently also uses) is in order. First of all, the good: this approach works in all Javascript-enabled browsers (in particular, Flash is not needed). But wz_jsgraphics is rather inflexible: it's merely a compiler for a few graphics primitives (lines, filled rectangles and XY-alligned ellipses) to an "assembly" language consisting of stacked DIVs. Because the library doesn't keep track of the DIVs associated with each primitive, there's no way to undo a shape (short of clearing the entire drawpad). wz_jsgraphics can also be slow (anything but rectangles and horizontal / vertical lines requiring large number of DIVs). However, these shortcomings aren't fatal for a diagramming application.

Open jACOB is supposed to be a bigger framework, including a server-side part, though at the moment there isn't much to see besides Draw2D. Overall, this is a promising start; hopefully this project will stay active and yield (further) useful results.

Adobe will discontinue the SVG plugin

Adobe will discontinue (end of life) their SVG plugin starting January 1, 2008. This is not so surprising given their new-found interest in Flash after acquiring Macromedia; what is surprising is that they plan to actually remove the plugin from the Adobe download area after 2009 (and no, third parties are not allowed to redistribute it under the current licence).

While Opera and Firefox have native SVG support, Internet Explorer, which still has the dominant market share, has no good alternatives (Mark Finkle's VML-based SVG emulation is only a start). This is sure to spark outrage among application developers (though, to be honest, everyone knows that other than Flash or DHTML, there is no safe way).

Update: Adobe has yielded to pressure and agreed to continue distributing the plugin indefinitely (though there will be no further releases, in particular no Vista version).