um.. hire him for galium/mesa/llvmpipe/x11 devs?
Originally Posted by siride
When I referred to complexity I was talking about computational complexity ... having fixed functions with only a couple of parameters tunables is way more easier to optimize and to make shorcuts than having more stages in the pipeline, and those not being "fixed", but programmable (specially 3.x, that's designed around shaders)
Originally Posted by Geri
Of course is going to be fast with OpenGL 1.x, when he implements 2.x or better yet, 3.x then I'll get amazed if he gets a similar performance to this or llvmpipe.
but yes, this does have a niche use case, but there's too much hype for what this actually is.
I agree with you. This is especially true because compositing window managers these days have a hard dependency on OpenGL 2.x, with GL 1.4 fallback paths quickly disappearing due to maintenance and performance issues. Some people, e.g. the kwin maintainer, even wants to require GL 3.x support, though I imagine that's still a little ways off from being implemented (in the sense that the GL 1.x AND 2.x renderers will be removed).
Originally Posted by vertexSymphony
The other aspect that reduces the utility of any potential optimizations you'd see in TitaniumGL is that these optimizations won't work for any hardware accelerated 3d paths on modern cards. Modern cards are all fully programmable and likely do not even have fixed function code paths, so the optimization techniques are completely different in order to achieve respectable GL 2.x performance on, say, Nvidia Fermi (GTX400 series) or ATI Evergreen (HD5000) or later. And since GL 3.x / 4.x is much newer, it's pretty much a trade secret within the halls of ATI and Nvidia as to how to make these new APIs fast.
What I'm saying is that, in the best case, TitaniumGL would be open sourced and we could draw some useful algorithms from it, for doing GL 1.4 on the CPU. Since these algorithms likely wouldn't be compatible with LLVM, they would only be able to affect the performance of the softpipe driver. And we'd have to somehow re-architect softpipe to use these faster algorithms for GL 1.4, while switching over to the slow old way for GL 2.x, because it's programmable, and TitaniumGL offers no advice on how to optimize a programmable pipeline.
This best case is not reality, though, because it's closed source and likely doesn't offer any truly novel algorithms.
Last edited by allquixotic; 03-11-2012 at 06:41 PM.
I don't think that's accurate. Have a link?
Originally Posted by allquixotic
What I understood, was that he wants the code kwin uses to run in the core profile without having to use any of the functionality that was deprecated in 3.x. So that it's simple to use the same code in GL2, GL3, and GL ES contexts. I don't think I ever heard of a plan to get rid of GL2 support, though.
By the time kwin supports OpenGL 3, the majority of free and open source video card drivers will support it too.
Originally Posted by smitty3268
It still has OpenGL 1.5 support for crying out loud, and he's only NOW talking about killing that off. OpenGL 1 is ancient and it's pretty hard to justify continuing to support it when almost nobody has hardware that old and its only other job is to be there to work around AMD's utterly craptastic proprietary driver.
I'm not sure the proprietary "TitaniumGL" malware (it opens sites full of ads every time something invokes it) which isn't even properly compliant with OpenGL 1 is even worth paying any consideration to.
Well maybe take a look at the OpenGL version string of a standard Intel netbook...
Even those have some (limited) support for GLSL shaders through an extension which should be sufficient for kwin's purposes.
Originally Posted by Kano
I tried activating kwin compositing on my Eeepc 901 before it broke down completely, turned the entire desktop into a slide show. Unless the "standard" improved significantly over the Eeepc 901, Intel notebooks just can't handle compositing.
Originally Posted by Kano
The Eeepc 901 is not a "notebook"; it's a netbook. Although it uses a similar Intel-manufactured GPU (not Imagination Technologies) to the ~2006 era laptops, it is slower for these reasons:
Originally Posted by Ansla
1. The memory in the netbook is slower/cheaper than laptop memory. It's DDR2, where you can expect DDR3 on a real laptop.
2. The Atom processor could be a bottleneck, since the CPU is heavily involved in graphics processing for such a small device. Atom processors are pathetic -- they don't hold a candle to something as "revolutionary" as a first-gen Core 2 from ~2007.
3. The mobo used is going to have a slower FSB and less bandwidth for transferring data between the GPU and the CPU and RAM.
I have a ThinkPad X61 which uses an Intel integrated GPU which is one generation newer than yours -- instead of 945, it's 965. By today's standards, it's still quite old. The CPU is a low-power Core 2 Duo. Even with these fairly pedestrian specs, I get extremely smooth performance with any compositor I can throw at it on Windows or Linux: Aero, Mutter, Cinnamon, Kwin, whatever. To put it simply, this is a 3 or 4 year old integrated graphics chip that's now 2 micro-architecture generations behind (it'll be 3 generations behind when Ivy Bridge hits later this year) and compositing is simply perfect.
Granted, any more advanced 3D on this hardware is going to get badly bogged down. But hardware-accelerated compositing for workloads like web browsing and office applications, works GREAT.
So saying "Intel's hardware makes compositing a slideshow" is a gross understatement. I can only imagine how fast it is with Sandy Bridge graphics, which you can buy today; or Ivy Bridge graphics, which you'll be able to buy later this year.
It was a typo, both Kano and I were actually talking about netbooks, not notebooks.
Originally Posted by allquixotic