The Perils of Open Source

Croquet is Open Source. This has had both a positive impact on the project and in some ways a decidedly negative impact. The positive is the positives that most open source projects enjoy - lots of interest and creativity building around the system, visibility, strong academic relationships - it even helps allay concerns of larger enterprise customers knowing that there will not be a Microsoft-type lock-in with a single vender.

From the start Croquet was developed completely out in the open. Even the very first, barely useful versions of the system were readily available to download, deconstruct, and criticize. Nothing wrong with this - we invited it, and the project profited from it. The big problem we had to deal with is people were disappointed with how much of the system was or wasn't working. I have heard people say "Yeah, I tried Croquet a few years back, but it.... " (you can fill in the blank with a number of choices). I can understand why people would be irritated. Some critical problems in Croquet took much longer for us to solve than we ever thought they would, we had spent a minimal amount of time on UI, back-end infrastructure, performance, etc... Getting something like Croquet to work at all was a monumental task. We didn't exactly have a model to work from. We were inventing - not reverse engineering.

Of course, anyone that has ever developed a larger project has seen these kinds of issues. I certainly have dealt with them many times. The big difference was no one saw any of my project's warts except my colleagues and me. And we worked hard to remove, or at least hide them before we unveiled the final polished application. Croquet was different - people have been able to randomly sample the state of the project and critique it based upon that sample. Even today, the Croquet API is not quite a user-centric architecture. It is much more akin to the Linux kernel, looking for a front end to empower the user and a back-end to help users find each other and provide additional services. On the other hand, it is doing almost everything we said it would - and it really works well. We have even started a company Qwaq, Inc. based upon the same open source system that you can download today. We are getting great reviews for our first product Qwaq Forums, even though it is till in beta today.

What is my point? I have enjoyed this very open development process. I have learned a lot, and made a huge number of new friends and colleagues. Overall, it has been fun in spite of certain comments from people. I do think that next time - if there is one - I will probably hold off releasing a new system until it is a bit more mature and robust. In some ways that is sad - I think people that have stayed with the project from the beginning have learned a lot about how a complex system gets built and how it evolves. Most of this would be missed if you were to jump into a more complete end-user experience. On the other hand, it would probably increase the probability of success. In marketing, you only have one chance to make a first impression. Qwaq Forums is making a GREAT first impression. It would have been nice if Croquet had the same opportunity.

David A. Smith

3D Worlds and Interoperability

I attended a working lunch this week at Harvard to discuss 3D interoperability. It was an interesting discussion. I think the biggest problem was simply the definition of interoperability. For some people at the conference, it meant as little as reconstructing someone elses content in another 3D environment, or maybe being able to somehow copy 3D data sets from one place to another. Others viewed it as being able to reuse and dress-up your personal avatar for shopping or for role-playing.

We even discussed the possibility of hooking Croquet up to Second Life via Croquet portals. This should be relatively straightforward to do - it would require a compound application of some sort, but since Croquet is already designed to hand off rendering to the adjacent Island (Croquet Islands and Second Life Islands are different kinds of things) when rendering through a portal, handing it to the Second Life client would not be much different. Coming back the other way might require a bit more finesse, as we would have to add some portal support to SL, and would have to call into an image based system. We have been doing something similar recently, so it is quite possible.

I think David Reed (one of my fellow Croquet architects) really nailed what 3D interoperability should be. When we share 3D objects, we also need to share their behaviors. In most ways, the visual representation of an object is its least interesting aspect. What it can do, and how it interacts with the users and the worlds around it, however is REALLY interesting and very valuable.

This is also really hard to do. Everyone uses different languages and scripts, and some - like Croquet - use a very different mechanism for enabling behaviors. Croquet has TeaTime and the concept of future replicated messages to manage its behavior. This enables a peer-to-peer approach to designing interactions, which otherwise would be near impossible. The only other solution is what everyone else has to do, which is maintain a central server and replicate the results of the computations.

UBC Joins Croquet Consortium

The University of British Columbia (UBC), home of the recently established Arts Metaverse project, has just joined the Croquet Consortium! We look forward to having our colleagues from UBC join the rest of us in helping to create open source tools to support the unique needs of higher education.

Arts Metaverse is a 3D virtual environment based on the open-source Croquet platform. It is being developed under the guidance of Tim Wang and Ulrich Rauch in the The University of British Columbia's Arts Instructional Suppport & Information Technology unit. Arts Metaverse is intended to provide a way for scholars, teachers, students, and interested individuals to create their own virtual spaces in which they can interact and collaborate with others.

Croquet was chosen as the foundational technology for the Arts Metaverse project because it provides:

• A powerful P2P network support. When Croquet runs, it automatically detects other computers that are running Croquet.
• Portal technology that allows application sharing between different operating systems. So that you can play a PC game with your Mac friends.
• Video conferencing and other communication tools without using server technology.
• Ability for users to freely define the space being created, providing “land owners” (the academics) complete customizable controls of the environment. (e.g. not just define the gravitational force in the land).
• Ability to back up the contents published using Croquet, take worlds on line and off line, and avoid many copyright issues.
• A structured p2p Croquet network that is much more secure than a server based large scale metaverse.