Still chiselling away at the event propagation stuff in 3Dwm. I actually spent Easter in Tarnaby/Hemavan a Swedish ski resort, so I haven't had the chance to do much than work on my tan and my downhill skiing, but now I am back in front of my computer again. My current challenge is computing the bounding volumes for the scene graph nodes and making sure that changes to these are propagated correctly in the graph. When toiling away at the design for this mechanism, I realized that this, and many similar things, are actually simply events that need to be routed and handled in the scene graph.
Armed with this discovery, I am now rebuilding lots of the scene graph code to also contain a generalized event framework. This will not only make it easy to add internal events like the bounding volume computation mechanism, it will also be excellent for input events that needs to be routed and handled by controllers in the scene graph.
Me and my friend Robert Karlsson, also a member of the 3Dwm core developers, are going to be attending a press seminar at the Museum of Architecture in Stockholm on the 24th of April. We will be presenting the project and demonstrating the wearable computer that we will use as a hardware platform for the system.