CL/GL interop didn't fail to work. It did work quite well. Despite this I have to admit that it is way more complicated than the DX11 compute shaders, BUT it DID work. In fact I could port DX11 compute shaders to OpenCL and make it work together with OpenGL. see:
http://www.gamedev.n...via-opencl-r233
I'm looking forward to trying out OGL compute shaders though, as it seems more reasonable to use it for processing textures / lighting.
The debugging feature is quite an improvement as such functionality was missing.

I'd consider OpenCL to be more of an alternative to nvidias CUDA than to DirectCompute aswell, OpenCL works without a OpenGL render context and can also be used with Direct3D (atleast on nvidia hardware, which is quite an advantage if you want to use different renderers but still use the same GPGPU solution), OpenGL definitly needed built in compute shaders aswell but OpenCL still has its place). One can debate if the OpenCL interop should be in core rather than as an extension though. (it might have made more sense to keep the interop functions as an extension and pushed in compute shaders earlier)

I think it's fair to say that both APIs have a healthy (or unhealthy, delete as appropriate) dollop of "worse is better" in them, so it really does come down to target platforms and personal preferences.

Regarding Intel, have you been following the Valve blog about porting Steam and L4D to Linux? Intel are definitely playing quite an active role, working with Valve, and taking feedback on board. Currently it's only the Linux driver, of course, but it seems reasonable to guess that some of the quality improvements coming out of this can also be fed into their drivers for other platforms.

The overall feeling here is definitely one of OpenGL coming into the ascendant again, while D3D appears to be languishing with a somewhat unknown/uncertain future. Can it be sustained? No idea, but the next few years sure won't be boring.

[quote name='samoth' timestamp='1344337679' post='4966978']
What else could it mean but serious OpenGL support from IHVs?

Maybe, or it could take the same route that OpenGL on Windows takes to some extent; make it work for Game X.

For some time if you wanted performance you had to hit the same path as iD games, maybe the same will happen when it comes to following Valve's lead onto Linux? Do it their way or fall off the 'fast' path.

We'll see how it works out - I remember when Linux games appeared in the shops for a short while around 1999 with the iD games going on sale; at the time that failed to set the world alight as it seemed no one wanted to buy them. Maybe, 10+ years on Linux users (note: users. I maintain Stallman is a crazy person) as a little more pragmatic about things and Steam will work out and enough of a market share will be carved out for a good feedback loop to be generated with regards to market share, driver development and tool development going forward.

My only 'worry' about that is the continued involvement of the ARB who, historically, simply don't make good choices.
OpenGL2.0 and 3.0 are proof of this and nothing they have done since then has convinced me otherwise - if gaming on Linux makes it then it'll be down to Valve, NV and AMD working together and not the ARB.

I'm watching with intrest to see how this pans out, not least of all because it might well affect my day job
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The big problem with IDs Linux push was that there was essentially only one game you could find in stores (Quake3) and the number of stores carrying the Linux version was extremely limited, most Linux users ended up buying the Windows version and downloading the Linux binary anyway since that was the easiest option (The pragmatic users went with the path of least resistance)

With steam the big change is that everything is available for everyone at any time and buying a game for PlatformX usually lets you install and play the same game on PlatformsY and Z aswell (So even users of dualboot systems don't have to choose between buying for Windows and buying for Linux, they just buy it and play on whatever OS they happen to be logged into at the moment) (Personally i primarily buy Windows versions even though i use Linux aswell since it is far easier to get Windows games running in Linux than vice versa and having to reboot or switch machine to play a different game is far too annoying (With work there isn't much choice, Linux is simply the better OS for what i'm doing (apart from some legacy ASP.Net systems i have to maintain that just won't work properly with mono)).

As for what Valves Linux move will do for OpenGL i'd expect pretty much the same as AAA OpenGL use on Windows and Mac have done, IHVs will optimize the paths used by big AAA titles, it doesn't really matter that much though, indie titles will not push the limits far enough for that to matter and end users don't care if random indie title X runs at 3000 fps or 6000 fps (They will however care if expensive AAA title Y runs at 25fps or 60fps but as long as the IHVs optimize for the AAA titles its all good), The API is fine, you can complain about the ARB making bad or slow decisions but the API itself is fine(it might not be perfect but it doesn't have to be), it gives developers access to the features they need on the platforms they're targeting and according to Valve OpenGL also still performs better on both Windows and Linux than D3D9 does and they did manage to get better performance in Linux than on Windows so overall things are looking decent.

The main problems i see with gaming on Linux, (apart from the low number of available titles) is hardware support, There still isn't a really good solution for more advanced controllers, the soundsystem(s) are a bit of a mess and the desktop enviroments take far too much tweaking to get really good(Which really scares users away, Unity might be easy to use but its a real pain if you want to do anything even remotely advanced while Gnome/KDE have become quite a mess in the latest versions.

When it comes to OpenGL the biggest problem is Apple, they add support for newer versions at an extremely slow pace, 4.3 will not be relevant for another 2-3 years (The main reason to use OpenGL is to support OS X, and that means using OpenGL 2.1+extensions today or possibly 3.2)

You guys are no fun . I was having so much fun with compute shaders (actually, still have ).
gravitational n-body: https://github.com/progschj/OpenGL-Examples/blob/master/experimental/XXcompute_shader_nbody.cpp

Linux + OpenGL : 3.17ms/frame
Win7 + D3D9 (270fps): 3.7ms/frame
Win7 + D3D9 (304fps): 3.29ms/frame

The 303.4fps was Win7 + OpenGL, not D3D9. But yes, D3D9's high per batch overhead is old news, what isn't old news is that (nvidias) OpenGL drivers are still good enough to take advantage of this. (Most "recent" games with both OpenGL and D3D9 renderers have gotten far worse performance with OpenGL and it does show that OpenGL performance is "good enough"). As for what OpenGL version they're using it is quite likely that it is 2.x since they didn't make a clean rewrite, (its based on the Mac version afterall).

I think people are over-excited about Valve's contribution to all of this. Desura has already been providing a viable portal for Linux games for some time now. I don't see Valve's entry as groundbreaking; rather, they do not want to be left behind. The endorsement of Valve however is good for OpenGL because Desura doesn't have the brand name recognition or pull that Valve has.