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OpenGL 3.0 Released, Developers Furious
ikol writes "After over a year of delays, the OpenGL ARB (part of the Khronos industry group) today released the long-awaited spec for OpenGL 3.0 as part of the SIGGRAPH 2008 proceedings. Unfortunately it turns out not to be the major rewrite that was promised to developers. The developer community is generally furious, with many game developers intending to jump ship to DX10. Is this the end of cross-platform 3d on the cutting edge?"
Part of the reason for DX's success is that nobody else seems interested in developing anything to compete with it. OpenGL is the only cross platform 3D API I'm aware of and it and DX are all that there is these days. GLs problem is that it isn't keeping up with the hardware. The "just use vendor specific extensions" isn't a realistic solution in most cases. Thus GL is suffering and DX is winning by default.
If someone like Apple did develop a good 3D API, it might do well. However nobody seems interested.
That's most of the problem though... they did rewrite OpenGL, then they scrapped it. So in the process, we got a few years of the new version not existing. And a year of communication (from ARB/Khronos) not existing, particularly frustrating after they'd spent the previous year saying they were going to work on communications and transparency.
Even better, GL2 was supposed to be a cleaned up API, so this was the second time they promised a rewrite and scrapped it.
So either they were completely wrong about the justification for the rewrite both times (which doesn't bode well for the group in charge of the API) or we are missing out on the benefits the rewritten API would have provided.
Probably the biggest problem was the communications though, if they'd admitted the problems as they happened, there probably would have been less backlash. As it is, everyone was still pretty much expecting the original 3.0 design, so not getting that, on top of a year's worth of promised status updated, on top of the previous poor communication the promised status updates were supposed to fix, on top of the promised-then-scrapped 2.0 update, etc. leads to unhappy community.
(For those not following the situation, advertised benefits included:
simpler api = simpler drivers = better conformance + fewer driver bugs
new object model = less need for consistency checking in drivers = faster drivers with fewer bugs
getting rid of outdated code paths = easier to understand the api, easier to tell what will be fast
probably some more I forgot)
.
Vista is approaching 20% of the market. Top Operating System Share Trend You can't expect expect Linux ports if entry level DX9l/DX10 outperforms OGL.
...and probably irrelevant in the longer term.
This is not the first time this has happened. GL2 was also supposed to be a cleanup, but turned out to be anything but. This latest fiasco is more significant as a failure of governance than of technology. All the right ideas were there; they were published in some detail over a year ago in the Pipeline newsletters. But the ARB very obviously a) can't agree to get anything meaningful done, and b) now has subzero credibility with developers. It's not coming back from that.
So yes, I think cutting-edge cross-platform 3D is dead for the next 2-3 years. Let's face it, it was never exactly healthy. It's not the end of the world. Linux share is currently growing mostly at the low end, netbooks etc, while the Mac seems to be thriving despite the fact that Apple doesn't give a flying fsck about gaming and never has.
Fast forward a couple of years, though, and things like Larrabee will be hitting the market; embarrassingly parallel hardware that can be programmed with standard languages and tools. The API's role as gatekeeper of functionality will be gone. And suddenly, 3D rendering libs can be written by anyone with the time and expertise, without having to go through Microsoft or the ARB or NV or AMD/ATi or Intel or anyone. Experimentation, competition, cross-fertilization, evolution. Remember Outcast's voxel engine? Seen things like Anti-Grain? This will happen.
(Or, yes, people could just reimplement the DXwhatever API directly, but that would be a little disappointing.)
Today was not a good day, by any stretch of the imagination. But it's not the end.
the legacy crud that plagues OpenGL.
Did you read "the deprecation model" (appendix e) of the OpenGL 3.0 spec? OpenGL 3.0 apparently provides for a mode (a "forward compatible context") that helpfully excludes deprecated "legacy crud".
This sounds very handy for people trying to update codebases - they can presumably switch to a forward-compatible context, do a build, see what breaks.
Choice of masters is not freedom.
MPC: So, you said Rage is a 60Hz game. Is it an OpenGL or DirectX game?
JC: Itâ(TM)s still OpenGL, although we obviously use a D3D-ish API [on the Xbox 360], and CG on the PS3. Itâ(TM)s interesting how little of the technology cares what API youâ(TM)re using and what generation of the technology youâ(TM)re on. Youâ(TM)ve got a small handful of files that care about what API theyâ(TM)re on, and millions of lines of code that are agnostic to the platform that theyâ(TM)re on.
MPC: Are you using DirectX 9 equivalent? For Doom 4 as well?
JC: Yes to both. Itâ(TM)s one of those things I get asked a lot. Whatâ(TM)s big and exciting for DirectX 10 or DirectX 11? Thereâ(TM)s not a whole lot of⦠really not a whole lot. The big touted geometry shaders were in many ways, a mistaken belief that people desperately wanted to create stencil shadow volume.
So less than a month ago John said that he's still developing with OpenGL and that DX10 isn't really a worthwhile improvement.
And congratulations on referring me to something he said ages ago, when you find something more recent feel free to reply
Oh and source of interview: http://www.maximumpc.com/article/features/e3_2008_the_john_carmack_interview_rage_id_tech_6_doom_4_details_and_more?page=0%2C0
Please stop modding up this troll.
That article is 6 years old.
Most of those patents are hardware patents totally irrelevant for OpenGL (or Direct3D for that matter).
Also, Microsoft is not a member of the group that actually writes the OpenGL specification. They have no vote on what gets in OpenGL or don't.
Of course this might give them leverage on some of the hardware vendors (like Nvidia) that will have to implement the new OpenGL standard in the future. But history does not show them trying to use this in any way against OpenGL.
But claiming they "own OpenGL" is nonsense.
Basically they've got tangled in the implementation details and decided to play it safe with OpenGL 3.0 instead of starting from scratch.
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What happened to Longs Peak?
In January 2008 the ARB decided to change directions. At that point it had become clear that doing Longs Peak, although a great effort, wasn't going to happen. We ran into details that we couldn't resolve cleanly in a timely manner. For example, state objects. The idea there is that of all state is immutable. But when we were deciding where to put some of the sample ops state, we ran into issues. If the alpha test is immutable, is the alpha ref value also? If we do so, what does this mean to a developer? How many (100s?) of objects does a developer need to manage? Should we split sample ops state into more than one object? Those kind of issues were taking a lot of time to decide.
Furthermore, the "opt in" method in Longs Peak to move an existing application forward has its pros and cons. The model of creating another context to write Longs Peak code in is very clean. It'll work great for anyone who doesn't have a large code base that they want to move forward incrementally. I suspect that that is most of the developers that are active in this forum. However, there are a class of developers for which this would have been a, potentially very large, burden. This clearly is a controversial topic, and has its share of proponents and opponents.
While we were discussing this, the clock didn't stop ticking. The OpenGL API *has to* provide access to the latest graphics hardware features. OpenGL wasn't doing that anymore in a timely manner. OpenGL was behind in features. All graphics hardware vendors have been shipping hardware with many more features available than OpenGL was exposing. Yes, vendor specific extensions were and are available to fill the gap, but that is not the same as having a core API including those new features. An API that does not expose hardware capabilities is a dead API.
Thus, prioritization was needed, and we made several decisons.
1) We set a goal of exposing hardware functionality of the latest generations of hardware by this Siggraph. Hence, the OpenGL 3.0 and GLSL 1.30 API you guys all seem to love ;\)
2) We decided on a formal mechanism to remove functionality from the API. We fully realize that the existing API has been around for a long time, has cruft and is inconsistent with its treatment of objects (how many object models are in the OpenGL 3.0 spec? You count). In its shortest form, removing functionality is a two-step process. First, functionality will be marked "deprecated" in the specification. A long list of functionality is already marked deprecated in the OpenGL 3.0 spec. Second, a future revision of the core spec will actually remove the deprecated functionality. After that, the ARB has options. It can decide to do a third step, and fold some of the removed functionality into a profile. Profiles are optional to implement (more below) and its functionality might still be very important to a sub-set of the OpenGL market. Note that we also decided that new functionality does not have to, and will likely not work with, deprecated functionality. That will make the spec easier to write, read and understand, and drivers easier to implement.
3) We decided to provide a way to create a forward-compatible context. That is an OpenGL 3.0 context with all deprecated features removed. Giving you, as a developer, a preview of what a next version of OpenGL might look like. Drivers can take advantage of this, and might be able to optimize certain code paths in the forward-compatible context only. This is described in the WGL_ARB_create_context extension spec.
4) We decided to have a formal way of defining profiles. During the Longs Peak design phase, we ran into disagreement over what features to remove from the API. Longs Peak removed quite a lot of features as you might remember. Not coincidentally, most of those features are marked deprecated in OpenGL 3