AVWorlds tests Bullet physics

AVWorlds is a brand new grid — at just 26 regions, it doesn’t even make our monthly Top 40 list — but it has big ambitions.

The grid launched with the highest priced land in OpenSim, but then abandoned that strategy and is now actually offering more free residential plots to residents than any other grid.

Today, the grid made another bold step, rolling out the Bullet physics engine. It can be tried out right now on the grid’s AVW Bullet region.

“The region seems very stable  and works great,”  AVWorlds CEO Alexsandro Pomposelli told Hypergrid Business. “I will be rolling out Bullet to all our regions next week.”

That would make AVWorlds the first OpenSim grid using anything other than the default OpenSim physics engine, ODE.

The Bullet region was set up by Dreamland Metaverse, the hosting company which provides the infrastructure and grid management services for AVWorlds, using the new BulletSim plugin developed by Intel’s Robert Adams, a new OpenSim contributor.

What is Bullet?

OpenSim has long been handicapped by the fact that it default ODE physics engine doesn’t perform as well as the Havok engine used by Second Life. Havok has also been used in hundreds of video games and dozens of movies. ODE — not so much.

According to Pomposelli, Bullet physics works as well as Havok — but without the steep price. Havok is free for individuals and non-profits but is out of the reach of commercial grids like AVWorlds. In addition, it has to be customized quite a bit in order to work with OpenSim, Pomposelli said.

“Linden Lab spent months modifying it,” he explained. “For me, it is clear that Bullet is the way to go.”

Bullet also required modification — but that part has been taken care of by Adams, who is a research scientist at Intel. The result was BulletSim, a version of Bullet that is compatible with OpenSim and will now be included in the standard OpenSim distributions as one of the alternatives to the default ODE engine.

Users won’t have to change anything to get their objects to work with BulletSim — all existing scripting commands work the same way they did before in OpenSim or in Second Life.

Robert Adams

“BulletSim uses the existing OpenSimulator physics engine interfaces so, when it is fully functional, a user should not notice a difference other than more perfomant physics,” Adams told Hypergrid Business. “As of today, BulletSim implements basic in-world physics — avatar movement, gravity, collisions, physical object interactions — and has code that starts to implement some of the more advanced in-world features, like linksets and vehicles.”

To enable it, Adams said, grid or region managers have to open the OpenSim .INI file and specify BulletSim as the physics engine. No other changes are required.

However, it is a new feature for OpenSim and early adopters will probably see some wrinkles that need to get ironed out, he warned.

“There is a lot to be debugged and tuned before BulletSim can be considered a replacement for the existing ODE implementation,” he said.

However, it has already been shown to work better than ODE in testing.

For example, the existing ODE engine can support 800 balls in a box of pegs at 30 frames per second — BulletSim can handle 1,900, more than twice as many, according to Adams.

Justin Clark-Casey

“Also, Bullet is more actively maintained,” OpenSim core developer Justin Clark-Casey told Hypergrid Business.

Unlike ODE, Bullet is actively being used in many high-profile projects.

For example, the Bullet physics engine was used in the Toy Story 3 video game, Grand Theft Auto IV, Sony’s Free Realms games, and Activision’s Blood Drive.  It also shows up on the big screen, where it was used for special effects in such movies as “Hancock,” “The A-Team,” “Sherlock Holmes,” “Megamind” and “Shrek 4.” It is also used in Blender for animations.

Much of the early testing of BulletSim has been done by OSGrid president Michael Emory Cerquoni (also known as Nebadon Izumi in world). He has uploaded a couple of videos of BulletSim in action.

However, Cerquoni isn’t rolling out BulletSim on OSGrid just yet.

“It’s still pretty far from ready for being used,” he told Hypergrid Business. “I have been testing it locally, there is quite a bit that still does not work right yet.”

I visited the AVW Bullet region on AVWorlds, rezzed some balls, and ran around playing soccer with them. That part worked fine. However, when my avatar was standing still, it would occasionally start to slide, on its own, across the flat ground.

I got the idea for kicking balls from the following video by Cerquoni, in which an avatar runs around a region filled with 4,000 balls.

maria@hypergridbusiness.com'

Maria Korolov

Maria Korolov is editor and publisher of Hypergrid Business. She has been a journalist for more than twenty years and has worked for the Chicago Tribune, Reuters, and Computerworld and has reported from over a dozen countries, including Russia and China.

  • Yes. It does need adjustments. Its not perfect yet. AVW BULLET is here to give us an idea and also so we can test it and report back to the developers. Anyone interested to come take a look is more than welcome. Feel free to join and test it for yourselves.

  • sarahblogging

    > when my avatar was standing still, it would occasionally start to slide, on its own, across the flat ground.

    That happens with my standard installation, too.

  • Yes the slide is one of the adjustments needed. Nothing really bad but our developer will start to look at this next week. Thats the name of the game. Tests and more Tests. But it is worth it. We will continue to support this development and aim to more fine tuned engine at the end.

  • Also forgot to mention that the idea here is to implement this new engine soon before the grid gets bigger. We are a new grid and it would be too much trouble to get a new engine placed in thousands of regions. So if we start growing with the BULLET all we need then is keep updating it as we go along but the grid would already have it in its roots. We have 26 regions now so the work wont be so extensive. So the advantage here is to take the momentum now since we are new and still growing.