Slowly but surely, the web is becoming a more hospitable place to host high-end games with sophisticated 3D graphics. That’s one of the reasons Unity Technologies says that version 3.0 of its game development platform is its most important yet.

Games with cool 3D graphics must often be loaded onto a computer via a DVD. Or they can be downloaded over the web in a very long transfer of gigabytes and gigabytes of data. That means that anyone with a weak computer or a slow broadband connection can’t play those games on their desktops. And forget about playing on a laptop or netbook.

But Unity makes a plug-in for web browsers that allows them to display high-end graphics without the disk loads or time-consuming downloads. If developers fashion their games using Unity’s development kit, their games will be able to run in web browsers. Today’s version 3 release of the Unity 3 development platform will enable 10-fold performance improvements and more than 100 additional enhancements to deliver better 3D games over the web.

Unity’s technology will likely always lag the performance capabilities of games that are stored on computers, but if it becomes good enough for most games, it could have enormous implications. One of them is the removal of friction from online games. Many online games with sophisticated 3D graphics can’t reach broader audiences because of the limitations of users’ computers and broadband connections. If those barriers are overcome through Unity’s plug-in technology, (which could eventually be built into browsers), then a lot more people would be able to play online games.

Unity has gained more than 200,000 registered game developers since it was introduced for the first time more than five years ago. By putting sophisticated 3D development tools in the hands of everyone, Unity is a force for democratizing game development, which has been the province of big companies on the game consoles.

“This audacious dream of building a truly unified platform for game development is coming to fruition,” said David Helgason, chief executive of Unity Technologies. “With tens of thousands of teams of every shape and size using Unity, across every genre and all major platforms, across all parts of the game industry as well as most other industries, economies of collaboration and sharing and scale of stunning dimensions are being realized.”

With Unity 3, Helgason said that the 3D graphics quality is going up, allowing for features such as beast lightmapping and deferred rendering. (That means that images will look even better than they previously did in Unity-based games). Unity has a free version of its product for entry-level developers. It charges $1,500 for its pro version.

Unity was started in Denmark and moved to San Francisco. The company’s platform is compatible with a wide number of systems, including the iPhone, iPad, PC, Mac, Android, Wii, Xbox 360 and the PlayStation 3. Game publishers using the platform include Electronic Arts, Disney, Cartoon Network, Bigpoint and Nexon. So far, users have downloaded the plug-in to play games based on Unity more than 35 million times.

The company was founded in 2003 by Helgason (pictured top right), user experience chief Nicholas Francis (top, middle), and chief technology officer Joachim Ante (top left). The company has 80 employees. Rivals include Epic Games’ Unreal Engine and Adobe’s low-end Flash technology.

The company raised a $5.5 million round from Sequoia Capital. Other investors include VMware founder Diane Greene and David Gardner.