SGI Releases OpenGL As Free Software

StoneLion writes "Since its release, the OpenGL code that is responsible for 3-D acceleration on GNU/Linux has been running on licenses that were accepted by neither the Free Software Foundation (FSF) nor the Open Source Initiative. Today, however, the FSF has announced that the licenses in question have been rewritten, the problems resolved, and the code freed. Peter Brown, executive director of the FSF, says, 'This represents a huge gift to the free software community.'"

Comments

How does this effect the OpenGL patents?

[Black Art]

There are still a number of patents covering portions of the OpenGL functions. Does this grant a license for use or are we stuck with partial implementations?

Re:How does this effect the OpenGL patents?

[RiotingPacifist]

IT completely removes the patent stuff from the license. So you can redistribute the code even if it breaks patents, but then of course your subject to the patent laws of your country

SGI's press release is pretty awesome too

[Anonymous Coward]

http://www.sgi.com/company_info/newsroom/press_releases/2008/september/opengl.html

Free Software Foundation and Khronos Group Both Herald New License of Industry Standard Graphics Software

SUNNYVALE, Calif. (Sept. 19, 2008) â" As software developers the world over prepare to mark the 25th anniversary of the GNU System, Silicon Graphics, Inc. (NASDAQ: SGIC) today announced it is releasing a new version of the SGI Free Software License B. The license, which now mirrors the free X11 license used by X.Org, further opens previously released SGI® graphics software that has set the industry standard for visualization software and has proven essential to GNU/Linux® and a host of applications.

Today's announcement affects software created by SGI that forms the building blocks of many elements of today's gaming, visual computing, and immersive experiential technologies, including a wide range of proven visualization solutions provided by SGI.

Previous SGI contributions to the free and open source community are now available under the new license. These contributions include the SGI® OpenGL® Sample Implementation, the GLXâ API and other GLX extensions. GLX provides the glue connecting OpenGL and the X Window Systemâ and is required by any OpenGL implementation using X. GLX is vital to a range of free and commercial software, including all major Linux distributions.

SGI first released the software under a licensing model in 1999. But now SGI is pleased to release an updated version of the license that meets the free and open source software community's widely accepted definition of "free."

"SGI has been one of the most ardent commercial supporters of free and open source software, so it was important to us that we continue to support the free software development community by releasing our earlier OpenGL-related contributions under this new license," said Steve Neuner, director of Linux, SGI. "This license ensures that all existing user communities will benefit, and their work can proceed unimpeded. Both Mesa and the X.org Project can continue to utilize this code in free software distributions of GNU/Linux. Now more than ever, software previously released by SGI under earlier GLX and SGI Free Software License B is free."

The important lesson here is.

[LWATCDR]

Don't be a jerk about it. From the article.

"Someone came to me on IRC and asked if people should start sending angry faxes to SGI, telling them to please clean up their licenses. And I was like, 'No, that's not the right message right now.' We were trying to avoid that kind of reaction, because among the people in the GNewSense community, there was a visceral reaction initially, and it took some time for people to realize that we needed to give them a chance. And it really paid off. SGI was very willing to work with us throughout the entire process.""

Re:The important lesson here is.

[JohnFluxx]

I think it depends really.

In the recent Ubuntu/Mozilla case, both Ubuntu and Fedora had behind-the-scenes quiet negotiations with Mozilla over the EULAs. However Mozilla insisted that it wanted and needed the EULA.

It wasn't until there was a fairly big uproar about it did Mozilla come back to the table to renegotiate.

So sometimes the squeaky wheel does get the grease :)

Big news

[mnmn]

I'm surprised that opengl was never really 'open'. It now makes sense why it wasnt a part of glibc and/or xfree86 until recently.

The opening of video card drivers and now opengl are major steps in the success of linux on the desktop (and for gamers).

Just imagine, we can now add opengl to Heretic and Command and Conquer, and it can all still be very much free. I can't wait for when I can port Halflife2 to Linux.

Re:Big news

[mikael]

SGI offered a sample software implementation of an OpenGL device driver to hardware vendors. This source code would provide a software specification of the way that any hardware should behave. It could be used as a fallback if a hardware vendor didn't choose to implement a particular feature of OpenGL functionality directly in hardware. It would be the responsibility of the hardware vendor to choose what to implement in hardware and software. Early consumer boards just did the rasterization, and used the Intel MMX2/AMD 3DNow! instructions to do the TLC (transformation/lighting/clipping).

A professional board or gaming card would do everything in hardware. Because of the way OpenGL is implemented, there are a multitude of ways of sending down geometry - any combination of vertices plus optional outward normals/texture coordinates/colors for triangles, quads, triangle strips, triangle fans, line or points. And these might be integers, 16-bit/32-bit/64-bit floating point. Each particular combination might or might not be optimized for the hardware. There was a big fuss in the past, because vendors chose only to optimize the particular combinations for the Quake game. Home developers were confused why their implementations would run slower than the real Quake.

For every possible option at a particular layer (vertex transformation, vertex lighting, vertex clipping, triangle rasterization), there would be a function pointer choosing which function call to make - either to the software implementation or writing to hardware registers.

Mesa-GL is a open-source implementation of the OpenGL specification, written by the open-source community and not SGI. OpenGL was originally a rewrite of SGI proprietary SGI-GL API which worked on all workstations from Indigo's to Extreme's. SGI was charging vendors a license fee for access to their software implementation, which included a verification test suite for hardware. Because of this, they were reluctant to make the software open source.

But with the evolution of 3D hardware, the free availability of an open-source version of OpenGL and the possibility that programmers might even get to be able to use the GPU to write directly to the framebuffer once again, it is strategic for SGI to make this software open source.

Before DirectX and OpenGL, game programmers only used either Mode 13 with 320x200x256 color palette (or other VESA 256 color modes) to write directly to the hardware. Programmers could just use whatever algorithm they could think of - use the 256 color-palette as a Z-buffer for rendering spheres, depth-shading effects, color cycling, sprite animation. Have 16 sub-palettes each a shade darker than the others and you could do shadow effects. Create a pixelmap C++ class that could be memory-mapped to the framebuffer, add some block copy, point drawing line drawing, textured triangle/quad filling routines and you have your own mini 3D API. Since the framebuffer itself was a pixelmap, you could use the framebuffer itself as a texture map (this technique was actually patented in hardware).

Re:Good news?

[apathy maybe]

The code was already "free" for a given definition of "free", however, three problems were identified.

The old licences:

• "forbid the distribution of code that infringes on somebody else's intellectual property rights"
• distributors of the code are required to obey any export laws that might apply
• require users to inform the distributor if they learn of any potential intellectual property infringement of code releases under the licenses

As such, it was easy to modify the code, but it wasn't free or open enough by the standards of either the Free Software Foundation or the Open Source Initiative.

OpenGL is a standard, just like Java is. The fact that there are many implementations of those standards doesn't mean that there is a problem. Besides which, it doesn't really matter, most people will code for the reference implementation (Sun Java and SGI OpenGL).

Re:Good news!

[BPPG]

What are you talking about? Hibernation requires you to draw two large black polygons to cover your screen to save power.

Just to set the record straight.

[Anonymous Coward]

This wont magically solve your driver issues.
This wont magically port your game to opengl.

The openGL headers have always been available to compile against.

This is the source for the reference implementation of openGL. It would be of interest if your planning on writing a 3D 'rendering' engine (not 3d game engine) from scratch, or are interested in how the opengl stack works.

FYI, mesaGL's source has always been readily available and is based off SGI's implementation.

Re:Is OpenGL a player anymore?

[ckaminski]

OpenGL has NOT gone the way of the Dodo, and as far as I know, is still kingpin of the 3D visualization world outside the gaming community (CAD/CAM/Modelling).

OpenGL was never very big in the gaming world either. Quake/HL was a standout in this regard, but most 3D game engines have been very custom, or based on DirectX - DirectX was sort of mandatory once game authors lost direct access to hardware.