Downsides of OpenGL [Blogpost]

[gorobei]

what was the last major game that used open GL?

rage is the last one, wolfenstein new order is the newest upcoming.

 

[Pottuvoi]

Clean start would be nice.

 

[Jodell88]

rage is the last one, wolfenstein new order is the newest upcoming.

There's also OpenGL versions of Metro: Last Light, BioShock Infinite, Borderlands and a few others.

 

[Elixer]

Nvidia's and AMD's OpenGL driver are the same on at Windows/Linux, it could be the same one they use on Mac OSX as well.

Not true.
AMD's 14.4's on windows is broken for a certain openGL call, and on linux, it works as it should.

Here is a post about the current state:
http://www.g-truc.net/post-0655.html#menu

 

[Jodell88]

Not true.
AMD's 14.4's on windows is broken for a certain openGL call, and on linux, it works as it should.

Here is a post about the current state:
http://www.g-truc.net/post-0655.html#menu

What G-truc is saying to what you're saying is two different things.

And the drivers are pretty much the same.

Q: About what percentage of the driver's code-base is shared between Linux and Windows platforms?

I'd estimate greater than 90% of the Linux driver is cross-platform code. The NVIDIA GPU software development team has made a very conscious effort to architect our driver code base to be cross-platform (for the relevant components). We try to abstract anything that needs to be operating system specific into thin interface layers.


Some examples:
The NVIDIA kernel module is nearly all cross-platform code; the majority of the same code for this component runs on Windows XP, Windows Vista, Windows Win7, MacOSX, Solaris, FreeBSD, and Linux. In fact, the exact same nv-kernel.o binary file can be used on all three of Solaris, FreeBSD, and Linux. The only bits that are Linux-specific are provided as source code in the kernel interface layer of the NVIDIA kernel module.


The NVIDIA OpenGL driver is mostly cross-platform; the only bits that are not cross-platform are abstracted into the window system layer (e.g., GLX, WGL).
The NVIDIA X driver is more UNIX-specific. It shares some code with the NVIDIA display drivers for other operating systems, but due to differences in window systems, it doesn't make sense to share a lot more code here.
The VDPAU driver leverages a lot of the low-level video decoding algorithms from the Windows video driver.


We couldn't provide the Linux product that we do if we didn't leverage so much common cross-platform driver code.

http://www.phoronix.com/scan.php?page=article&item=nvidia_qa_linux&num=2

Similar situation at AMD.

 

[Elixer]

What G-truc is saying to what you're saying is two different things.

I didn't mean for those things to be related... I was just stating what I found, then, I was stating what I read at G-truc's site...

And the drivers are pretty much the same.
http://www.phoronix.com/scan.php?page=article&item=nvidia_qa_linux&num=2

Similar situation at AMD.

And I am saying, it isn't the case for my specific code. I have code that works with 14.4's on linux, and is broken on 14.4's on windows.
While they may share lots of things, there is some stuff, for whatever reason, that isn't shared and they diverge.

 

[Jodell88]

And I am saying, it isn't the case for my specific code. I have code that works with 14.4's on linux, and is broken on 14.4's on windows.
While they may share lots of things, there is some stuff, for whatever reason, that isn't shared and they diverge.

Ah gotcha. Any idea what feature is broken?

 

[blackened23]

Since the guy at Valve stated essentially the same, I really feel that AMD's most detrimental aspect is the fact that their software team does NOT have the funding or manpower than nvidia has. Intel has the manpower, but they apparently just don't care (which is understandable, since they're not pursuing the same segments that AMD/NV are for dGPU). The comments from the Dolphin developer and this guy from Valve re-inforce this fact. In fact, the guy from Valve basically stated "AMD are idiots in terms of software as a corporation".

There have been numerous reviewers that have mentioned this. Ryan Shrout from PCPer. He visited both AMD and NV numerous times, and on one podcast I remember him stating that NV just had way more people for software development than AMD, and it generally shows. Ryan here at AT also made a similar remark around a year back, speculating that NV had more manpower. Josh Walrath, as well, has also made similar remarks about how AMD doesn't invest ENOUGH in their software teams.

I just don't get it. Hire some more people for software. While it's true that OpenGL needs a reboot, seeing all of the issues with Mantle beta drivers and the continued fix one thing break two other things software status quo from AMD, this really needs to change. AMD is making more money now. I cannot understand why they INSIST on spending that money on marketing instead of software man power. Software makes hardware. It always has. They have a lot of potential here with Mantle, but we see Mantle working on some cards and not others and Beta/WHQL drivers fixing one thing and breaking 7 other things.

I really, really, truly wish that situation would fix itself. Yes, OGL needs a reboot. But reading those comments on AMD's driver team from a Valve developer was really telling. You could literally interchange those comments with their DX driver, it was and probably still is a similar story. AMD makes great dGPU hardware, not perfect, not always polished, maybe not as refined as NV at times, but still great hardware nonetheless. The performance for AMD GPUs is generally always there and competitive. Not always the king of the hill, but competitive. But software can really drag an otherwise good experience down. Here's hoping that AMD actually hires some more freaking people for their software development team. It would just be beneficial for everyone, and would up the ante in terms of competition. IMO. I really want AMD to fix this because it has been their Achilles heel for a while. And you have to wonder how this will play out for the upcoming Wolfenstein game, which of course will be using OGL.

 

[Obsoleet]

This is why as long as the price/performance crown is still as dramatically in AMD's favor as today when SteamOS is v1.0 and taking off that if I buy a GCN card I'll have OGL and Mantle, vs with NV stuck with just OGL. It's been all-AMD bang for buck domination since the post GF8 era, and I doubt this will change anytime soon.

I suspect when Oculus and SteamOS are here, I'll be rocking a GCN card for both. Certainly don't want to be stuck with Nvidia/OGL-only in the SteamOS era.

 

[Elixer]

Ah gotcha. Any idea what feature is broken?

Yeah, and AMD's developer relations does know about it, and they said they would fix it, but, there has been no word yet on when.
It was reported to them with example code about 3 1/2 months ago, and I really did hope the 14.4's would fix it, but, alas, they didn't.

 

[24601]

Linux needs to seriously think about replacing OpenGL with a DirectX emulator.

OpenGL has fallen flat on its face since it's original inception, and it's not getting any better.

I have personally watched people try to design engines in OpenGL and its just madness how buggy every single aspect of OpenGL is ubiquitously on every level in every version.

 

[3DVagabond]

It's all about ROI. Until games are made on OpenGL with any frequency, AMD isn't going to invest much into it. As far as AMD being idiots, that's just what some people would like to believe. Look at their execution on the GPU side, both hardware and software, and it suggests otherwise.

 

[Elixer]

Linux needs to seriously think about replacing OpenGL with a DirectX emulator.

Right... DX isn't open, so, it will never, ever happen. Wine does do emulations of DX into openGL though.

While the state of openGL is better today than it was in the past, it still full of thorns.
Maybe openGL 5.0 will finally take a broom to what needs cleaning out.

 

[Mondozei]

AMD is indeed rumored to have terrible OpenGL drivers, but his rant kind of misses the mark. They've put their A-team on Mantle and AMD is already ahead of Nvidia on single-stream 4K monitor support.

So my main point is that while the OpenGL drivers are pretty bad(or so everyone, essentially, says), his bitterness in that narrow area has overshadowed his judgement overall by condemning the entire driver space.

Overall, I expect the OpenGL problems to gradually become resolved if SteamOS starts to take off. We're already seeing major game engines supporting native Linux desktop support in increasing numbers. SteamOS isn't a desktop OS, but it is more or less a skin of one, based on debian.

 

[BrightCandle]

AMD has always had bad openGL drivers, back 10 years we used to all be complaining about it. I guess its just one of the reasons why DirectX grew while OpenGL shrunk. Since now there is a good chance of openGL coming back reasonably strongly as its a lot more portable it would be nice for them to get it fixed, for their customers sake.

 

[blackened23]

There's also the fact that OGL is used for things other than gaming. In the context of professional applications, many use OGL. Perhaps that's one of the many reasons why AMD has not done so well in the professional sector. It would be another situation of great hardware, while software is questionable in some areas. Software is an area where NV throws a lot of money, and it does show since CUDA has picked up so much steam, and they put a lot of attention into OGL as well. I simply think AMD needs to put more money to the same thing. Everyone benefits, AMD users and competition alike.

Either way, their software engineers clearly need more manpower. Not just OGL, for everything. I won't get into specifics but it was all too obvious during the Tahiti era. Too many people in the know from review websites that have visited AMD stated exactly that, and here we have a developer from Valve have stated the same thing. He pulls no punches in saying that AMD are incompetent software wise as a company. AMD has issues with software, and that would include OGL. It doesn't hurt anyone but AMD to say screw OGL, OGL is for more than just games.

But it is clear from the context of gaming that OGL could use a reboot. I say, do that. And AMD should hire way more people for their software engineering. It seems to be a clear turnover/manpower issue where they can devote their time only in a narrow focus, but that hurts the broad picture. I also don't get the push-back at this notion of AMD diverting their funds away from their stupid marketing nonsense towards software. It hurts no one for AMD to have more software manpower but benefits everyone. Clearly a lot of people stating just that, and these aren't forum goers, they're real reviewers and game developers in the know - AMD has more money now and they could do it if they wanted. The question is will their management be smart enough to do it. I think they should be. Yet their management hasn't always been smart.

 

[monstercameron]

Right... DX isn't open, so, it will never, ever happen. Wine does do emulations of DX into openGL though.

While the state of openGL is better today than it was in the past, it still full of thorns.
Maybe openGL 5.0 will finally take a broom to what needs cleaning out.

lol, I just have to; Wine Is Not an Emulator

 

[f1sherman]

The truth about OpenGL driver quality.
http://richg42.blogspot.com/2014/05/the-truth-on-opengl-driver-quality.html

Vendor B driver's key extensions just don't work.
They are play or paper extensions, put in there to pad resumes and show progress to managers.
Major GL developers never use these extensions because they don't work. But they sound good on paper and show progress.
Vendor B's extensions are a perfect demonstration of why GL extensions suck in practice.

Coming from Valve engineer ^^, guess this pretty much explains why Vendor A is used across the board for graphics in Steam Machine.

 

[monstercameron]

Vendor B driver's key extensions just don't work.
They are play or paper extensions, put in there to pad resumes and show progress to managers.
Major GL developers never use these extensions because they don't work. But they sound good on paper and show progress.
Vendor B's extensions are a perfect demonstration of why GL extensions suck in practice.

Coming from Valve engineer ^^, guess this pretty much explains why Vendor A is used across the board for graphics in Steam Machine.

like these:

1. http://www.woot.com/offers/cruel-tease-sbx-wt01-steam-game-console
2. http://www.pcgamer.com/2014/01/07/cyberpowerpc-reveals-its-500-steam-machine-2/

 

[Jodell88]

Yeah, and AMD's developer relations does know about it, and they said they would fix it, but, there has been no word yet on when.
It was reported to them with example code about 3 1/2 months ago, and I really did hope the 14.4's would fix it, but, alas, they didn't.

I guess Unigine ran into the same problem? (maybe you work for them? :biggrin
Unigine's Heaven and Sanctuary benchmarks wouldn't run on Windows when using OpenGL. http://www.phoronix.com/scan.php?page=article&item=amd_r9hawaii_linwin&num=2

 

[exar333]

It's all about ROI. Until games are made on OpenGL with any frequency, AMD isn't going to invest much into it. As far as AMD being idiots, that's just what some people would like to believe. Look at their execution on the GPU side, both hardware and software, and it suggests otherwise.

Interesting post, because this whole thread seems to say otherwise. I like AMD products too, but they have a long way to go in some software areas, and you can't dispute the facts laid-out in this thread on OGL compatibility. It is embarrassing for AMD, honestly.

 

[BrightCandle]

Back in the day when a lot of OpenGL games were about AMD was famous for having problematic drivers. AMD has had a series of scandals around their drivers in the past couple of years, so while they have clearly improved (you couldn't even install their drivers before and a lot of games just crashed) the fact is they still have quality issues not just on openGL but on DirectX as well.

One of the ways in which we often see this is that initially a lot AAA games come out with poor performance. The reports are that Wolfenstein New order for example has serious FPS issues out of the box. AMD will no doubt release an updated driver that will fix it. But there is an issue here, AMD does a lot of releasing of drivers to fix problems with particular games, if they don't care enough about a game you can get and continue to have problems. It usually takes them a couple of weeks to get a game working well. This dependence on the driver team to fix the code to make that one game work is exactly the issue they are talking about on openGL as well.

All of this workaround like culture from AMD is driving a bigger problem, its sapping time away from the development team. They must spend a lot of time with particular games putting in one off fixes which only deducts time away from them for dealing with making the drivers overall better. AMD needs a culture change in its driver team or this problem is just going to continue forever.

 

[Jodell88]

Back in the day when a lot of OpenGL games were about AMD was famous for having problematic drivers. AMD has had a series of scandals around their drivers in the past couple of years, so while they have clearly improved (you couldn't even install their drivers before and a lot of games just crashed) the fact is they still have quality issues not just on openGL but on DirectX as well.

One of the ways in which we often see this is that initially a lot AAA games come out with poor performance. The reports are that Wolfenstein New order for example has serious FPS issues out of the box. AMD will no doubt release an updated driver that will fix it. But there is an issue here, AMD does a lot of releasing of drivers to fix problems with particular games, if they don't care enough about a game you can get and continue to have problems. It usually takes them a couple of weeks to get a game working well. This dependence on the driver team to fix the code to make that one game work is exactly the issue they are talking about on openGL as well.

All of this workaround like culture from AMD is driving a bigger problem, its sapping time away from the development team. They must spend a lot of time with particular games putting in one off fixes which only deducts time away from them for dealing with making the drivers overall better. AMD needs a culture change in its driver team or this problem is just going to continue forever.

While AMD does have buggy OpenGL drivers, part of their problem is Nvidia not following OpenGL specifications.

 

[zlatan]

... problem is Nvidia not following OpenGL specifications.

Actually the real problem is that OpenGL has a very bad specification. Some features can be implemented in two or three different ways. In this case every implementation is valid ... just not compatible with each other.