Last weekend I went to the 10th Free and Open Source Developers European Meeting in Brussels. This year was the first time that FOSDEM had hosted a track on Mono, so I went along to find out what’s going on with Mono, tell the Mono folk what our plans are for C# and fill in some gaps.

I started Saturday on the monitoring track which included a terrible talk about an interesting tool that I hadn’t heard of: SystemTap — a scriptable system monitoring tool designed to allow diagnosis of problems at run time on production servers without the usual instrument, compile, analyse loop. stap looks really interesting and useful as a tool for augmenting or replacing our current simulator performance tools.

After the stap talk I headed over to the XMPP track for the rest of the day and saw some great talks on BOSH, onsocialweb, pubsub, strophe.js, collecta and node.js. Federated, open social networks seem to be a big thing at the moment (@blaine was talking about them at @scalecampuk ) and there was lots of interest in using XMPP to build them as it already has standards for identity, presence, friends and events. Given that jabber and XMPP is a decade old it makes you wonder why the standards weren’t used the first time round. A possible reason is that XMPP doesn’t have it’s rails/django yet and still looks pretty clunky to work with although Strophe.js may help. Another reason may be that XMPP hasn’t been the web up until now, although BOSH may be the bridge that’s needed there.

While everyone else was thinking about using XMPP to build Twitter and Facebook I started thinking about what an open, federated virtual world platform built on XMPP might look like. I wasn’t the only one. The realXtend folks turned up to show off their latest new from the ground up viewer which uses XMPP and jingle for voice and IM integration and were obviously thinking along the same lines. As realXtend seem to be moving away from SL tech now, expect an XMPP based back end from them soon…

I spent Sunday camped out in the Mono room which was interesting from a cultural point of view. Miguel de Icaza seems to have completed his transition from champion to enemy of freedom in the open source community’s eyes. Last time he was at FOSDEM he was accused of talking about “Coca Cola” when showing off the closed source Unity engine that uses Mono, so stayed strictly to open technologies in his talk this year. Luckily, due to Microsoft’s Community Promise and open sourcing of the DLR, IronPython and IronRuby, that includes a lot of the .NET platform and gave him lots to talk about. Most of the legitimate worries of patents around Mono have been resolved, but talking about C# and the CLI at FOSDEM still requires a poster asking people to leave their religion at the door, apparently.

In my Second Life talk, I gave a summary of the interesting things we did to get LSL on Mono working in 2008 and then outlined our plans for C# in the future including lots of question marks around how we’re currently planning to implement them. Lots of my questions were answered after the talk and it turns out that the Unity developers are wrestling with the same problems at the moment, so we should be able to work together over the next few months to make a lot of progress.

Overall FOSDEM was hugely informative and enjoyable and I have a big shopping list of exciting new technologies to play with over the next few months. Hopefully the Mono room will become a regular fixture and we’ll be able to head back next year.

Was without a doubt the phrase I heard most often yesterday, especially if you include variants like “Not Like Second Life”, “A bit like Second Life” and “Unlike Second Life”. Whatever else it’s achieved, Second Life has definitely become the frame of reference for the small and somewhat myopic crowd that made up the delegates at the sparsely populated Virtual Worlds Conference in London yesterday.

Vastpark is not like Second Life because it works in a web browser. Everyone on the web integration panel seemed to agree that virtual worlds in a browser is the next step, so I was glad to be there to question the TechCrunch consensus. How does having a world in a browser help? What does back and forward mean to a virtual world? What does it mean for presence to have 10 tabs open looking in to different parts of the same virtual world? Why would you want your view further constained by extra web browser widgets? Isn’t 3D in the browser going to be a blood bath for the next few years? Aren’t you really just using the browser as a download path? I suggested that the final question was the real reason that developers are pushing virtual worlds on the web and that the integration that most people want is to be able to use existing web and 2D media while using virtual worlds and use web services as a universal data bus between virtual worlds and other web aware platforms.

MPEG-V is not like Second Life because it’s a standard defined by 35 companies which is much better than the emerging Linden led standard according to Dr. Yesha Sivan in what was the worst talk I’ve heard in a long time. Not only did he make the standardisation process sound like a 3 year political bun-fight by people who didn’t know much about virtual worlds and who might come up with a bad standard, he managed to spell MPEG and Google incorrectly, called Sun’s Darkstar, Blackstar and attributed a Ugotrade quote to Philip Rosedale amongst other clangers. He was roundly rebutted by a large part of the audience including Tara5 Oh who questioned the need for old fashioned standards processes in the web era. Thank goodness for rough consensus and running code.

Most of the virtual worlds talked about in the investment panel were not like Second Life, but were nearly all Club Penguin clones. This copy the big exit attitude was called out by one of the audience as it seemed to be at odds with a lot of the talk about wanting to back the first in a market, but at least one of the panel is still looking for a successful 18+ social world play. The panel ended with a show of hands from people wanting money and people wanting to invest, but the economic climate made the whole affair very muted with lots of the panelists saying that they are slowing down rates of investment as it’s difficult to get existing companies off their books.

As with Virtual Policy 08 and the Virtual Worlds Forum the most valuable parts of the conference were the spaces between sessions. I had another very worthwhile discussion with Adam Frisby of OpenSim about C# script compatibility between OpenSim and Second Life. The straw man design we talked about was to have an idiomatic .NET interface for event handling that can be used by C# scripts and adapted for LSL scripts and a set of static library methods for manipulating the world that would be used directly by LSL scripts and wrapped by user created libraries to provide an idiomatic object oriented interface. Adam was particularly interested in the idea of user created wrapper libraries as it would allow the creation of an OpenSim interface library that could be ported to Second Life and implemented in terms of the ll* static methods. OpenSim could then agree to support the common behaviour of this library in Second Life and OpenSim instead of having to support the gamut of ll* methods some of which don’t map well to OpenSim internals. As well as defining a common set of events and ll* static methods that are supported on both platforms there would need to be a way of extending the interface with new events and library methods. In addition Adam was interested in making the event propogation configurable so that a single script could respond to events on many objects in a scene. This would effectively add a script interest management layer to OpenSim’s scripting interface. Where platforms provide differing interfaces to scripts we would also need to decide how scripts query the available interfaces or how they behave when interfaces are not available.

Overall a worthwhile trip, but not because of the conference. This Friday I’ll be talking at the online head conference about conferencing in Second Life which has the advantage of requiring no travel making marginal conferences like the Virtual Worlds Conference less risky to attend while allowing all of the serendipitous networking opportunities that make real life conferences worthwhile.