Latency Onlive


We briefly discuss in the book the new class of thin client service characterized by OnLive and Gaikai. They require very little local client software, but at the expense that the images are computed remotely. Thus, the worst case end to end latency becomes the local latency (i.e. there is no longer any local control of camera direction, immediate actions such as firing etc.). This is the difference between locall end-to-end latency and distributed end-to-end latency (Paths A and D in Figure 10.1!).

Anyway, Digital Foundry have measured the latency of Onlive:

OnLive latency has finally been measured, and the results are pleasantly surprising. In Digital Foundry's independent tests, we achieved an optimum response of 150ms - similar to playing Killzone 2 locally, and in line with Rare's claims for lag when using the new Kinect camera controller.

They've used a simple video camera technique to measure latency, which we'll have more to say about in one of our first articles; the method is easy to reproduce but prone to some confounding factors. It is, however almost the best you can do for a game engine though it doesn't very accurately tell you about the network. A lot has been done in the VR community recently about more precise latency estimates, but they've used input systems that you have more control over.



NetGames 2010


The 9th Annual Workshop on Network and Systems Support for Games (NetGames 2010)
(in conjunction with ACE 2010)
November 16 and 17, 2010
Taipei, Taiwan

The 9th Annual Workshop on Network and Systems Support for Games (NetGames 2010) will be held in Taipei, Taiwan, on November 16-17, 2010. The NetGames workshop brings together researchers and developers from academia and industry to present new research in understanding networked games of today and in enabling the next generation of future networked games. Submissions are sought in any area related to networked games.

Important Dates:

Paper registration: July 19, 2010
Paper submission: July 26, 2010
Author notification: September 24, 2010
Camera ready submission: October 15, 2010
Workshop dates: November 16-17, 2010

Website Back


Apologies for the extended downtime on the site: the site disappeared behind the institutional firewall for a few days. More material, including updated versions of all the code samples coming in the next week.

Ryzom Goes Open Source



PARIS, FRANCE, May 6, 2010 -- Winch Gate Properties Ltd, the developer and publisher of massively-multiplayer online science-fantasy role playing games, is proud to announce the release of the source code and artistic assets of the popular MMORPG Ryzom to the Free Software Development Community.

Developers can now access the source code of the end-user client, content creation tools and server in order to make modifications, enhancements or to create their own virtual worlds. This move marks a milestone in Ryzom's long history and dedication to the free software movement. In order to ensure that Ryzom continues to grow and foster as a free software project, Winch Gate is now releasing Ryzom under the terms of the Free Software Foundation's GNU Affero General Public License.

Winch Gate is also excited to provide the free software community with high quality professional artistic assets including 3D objects, animation tracks, particle effects and thousands of textures. All of the Ryzom artistic assets will be licensed under the Creative Commons Attribution-ShareAlike to ensure that they and any derivative art will be available to all free software projects. These assets will be hosted in a new online repository in partnership with the Free Software Foundation.

By freeing Ryzom code, Winch Gate is transforming the MMORPG marketplace and is setting a precedent for how gaming software should evolve--in freedom. The source code released totals over two (2) million lines of source code and over 20,000 high quality textures and thousands of 3D objects.


Second Life Services


Howard Look gave the keynote speech at IEEE Virtual Reality last week. He talked about Linden Labs' plans for the next few years of development. Apart from better user experience through better client viewer software, he talked about the back-end services and their plans for openning these services up. As noted elsewhere in this blog, the openning up of the client software meant that both new clients and replacement servers were built. However, up until now the official server has been a closed box (albeit one which you can buy in a 2U case for your corporate data center).


The key point about the services was the number of services proposed. Howard's slides mentioned:

  • Linden Dollars
  • Map
  • Chat
  • Voice
  • Media
  • Search
  • Scripting
  • Events
  • Physics
  • Groups
  • Identity
  • Presence
  • Inventory
  • Classifieds


A second important point was that they were working with the IETF on some of them; some of the functionality competes with existing standards, so it'll be interesting to see if Linden move to supporting such standards.