Google has partly scrapped a browser plug-in project called O3D, instead throwing its full weight behind a 3D Web graphics technology called WebGL that got its start at Mozilla.

The move, first reported by CNET, has the potential to simplify the effort to bring hardware-accelerated 3D graphics to the Web, an idea that has appeal to those trying to refashion it as a foundation for applications such as games. However, it also means the functioning--if experimental--O3D technology is going back to the drawing board for a while.

The overall idea of O3D, a higher-level interface than the 3D nuts and bolts provided by WebGL, will live on, though. Google is rebuilding it as a library of pre-build software others can use on top of a WebGL foundation, Engineering Director Matt Papakipos and programmer Vangelis Kokkevis announced the move on the final O3D blog post Friday.

One of the big changes with the O3D rebirth is that instead of running as a fast, compiled C++ program, the library instead will use the relatively slow JavaScript used in Web applications. Fortunately for the project, the top five browser makers--Microsoft, Mozilla, Google, Apple, and Opera--all are making significant improvements in JavaScript execution speed.

Another tricky issue is that WebGL is a variant of the 3D graphics interface called OpenGL, which is used on Mac OS X and Linux as well as the iPhone and Android phones. On Windows, though, it's second fiddle to Microsoft's Direct3D interface. Google hopes to bridge that gap with its ANGLE project to translate OpenGL commands into Direct3D parlance.

Said Papakipos and Kokkevis:

We did not take this decision lightly. In initial discussions we had about WebGL, we were concerned that JavaScript would be too slow to drive a low-level API like OpenGL and we were convinced that a higher level approach like the O3D scene graph would yield better results. We were also cognizant of the lack of installed OpenGL drivers on many Windows machines, and that this could hamper WebGL's adoption.

Since then, JavaScript has become a lot faster. We've been very impressed by the demos that developers have created with WebGL, and with the ANGLE project, we believe that Chromium will be able to run WebGL content on Windows computers without having to rely on installed OpenGL drivers.

There's another obstacle yet, though: Apple, Mozilla, Opera, and Google are working on WebGL support, but Microsoft, despite its IE9 browser overhaul, appears to have little enthusiasm.

Asked in an interview this week about Microsoft's WebGL stance, Internet Explorer General Manager Dean Hachamovitch said, "I think it's different markup," meaning something not universally supported on browsers. "You're telling developers, 'Go write something else.'"

Google's answer: Chrome Frame, a plug-in that sneaks a copy of Chrome into Internet Explorer, an idea Microsoft scorns.

Said Henry Bridge, another Google programmer involved in the effort:

As for IE, we could have gone down the route of making the O3D plug-in also ship WebGL for IE, but we realized that then developers would be lacking other APIs [application programming interfaces] that they need for their apps, like Audio or WebSockets. If we then added those APIs to the O3D plug-in also, well, it starts to look a lot like ChromeFrame: a plug-in implementation of Web APIs for IE. We're confident that ChromeFrame will be as easy if not easier to install than O3D, so it seemed better to focus the team's graphics expertise on making WebGL great in Chrome/ChromeFrame and on making the O3D library useful to developers.

Canceling O3D also ruffled some feathers.

"I spent a lot of time learning and developing for O3D and now I got stabbed in the back. Very disappointing," said one O3D programmer, Angelo Franco, in a mailing list message. He did back down a bit, though, adding later, "Please keep up the good work with the JavaScript library. For sure, I'll continue to use it, despite the WebGL."