S3TC Now Golden For Linux & Open-Source?

Many Phoronix readers have written in asking about the news this week concerning HTC joining the Open Invention Network. In particular, many Phoronix readers are interested in HTC joining OIN due to their acquisition of S3 Graphics earlier in the year and the accumulated graphics IP portfolio.

The Open Invention Network issued a press release where they announced 28 new companies and organizations joined OIN to support Linux during this past quarter. Notable OIN licensees during this past quarter include HTC and LG Electronics.

For anyone that happens to have been living under a rock the past few years, any individual or company is able to use Open Invention Network patents as long as they agree not to assert their own patents against the Linux stack. Here's their official description about how this works, "Patents owned by Open Invention Network are licensed royalty-free to any company, institution or individual that agrees not to assert its patents against the Linux System. This enables companies in the OIN community to continue to make significant corporate and capital investments in Linux – helping to fuel economic growth. By broadly licensing its rapidly expanding patent portfolio, OIN is disseminating protections across the Linux community and promoting an active dialogue among entities committed to freedom of action in Linux. The web of Linux developers, distributors, sellers, resellers and end-users that license OIN’s patent portfolio acknowledge and affirm OIN’s commitment to enable Linux and address the ongoing threat from companies that seek to limit, exclude or tax open source initiatives."

Among the S3 patents that are relevant and sought after by open-source graphics driver developers is that for S3 Texture Compression (S3TC), which is commonly used by many modern OpenGL games and applications for compressing textures.

The S3TC compression algorithm for textures has been implemented as an external Mesa library since developers have been concerned about legal action by S3 Graphics / HTC. Some enthusiasts build and use this library, but overall it's not widely used nor shipped by default in the tier-one distributions. S3TC is, however, needed by many newer OpenGL games and applications as it's become rather critical in the OpenGL world for compressing textures well.

Over the years of S3TC being important, there's been various attempted workarounds, but nothing that has allowed it to be enabled by default. Back in September I heard the S3TC patent might be invalid due to a recent court ruling with HTC, but I haven't heard anything since.

Assuming the S3TC patents are covered by HTC with their OIN commitment (or if the S3TC patent is invalid), the texture compression support should quickly be pushed into Mesa and enabled by default.

S3TC isn't the only worthwhile patent in the S3/HTC portfolio, but there's more than one thousand graphics-related patents assigned to S3 Graphics. (See this Google Patents search.)