A look at GNOME Shell [LWN.net]

A look at GNOME Shell

Posted Jun 10, 2010 14:13 UTC (Thu) by michaeljt (subscriber, #39183)
Parent article: A look at GNOME Shell

I've complained about this before in other places, but what effects does GNOME Shell actually use that require an accelerated 3D graphics card? I don't have hardware I can use it on without installing a proprietary driver (which I haven't yet bothered doing), but it looks to me from the videos I saw as if most of the time things are running with all windows at their normal size at their normal angle relative to the viewer, and from time to time they are zoomed in and out. I really don't see why that needs accelerated hardware. I do understand that they are using a generic engine (Clutter) for this which can do lots of other fancy things that won't work as well without acceleration, but surely this sort of edge case could be detected somewhere in the stack and fall back and work nicely even without acceleration.

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A look at GNOME Shell

Posted Jun 10, 2010 15:06 UTC (Thu) by MisterIO (guest, #36192) [Link]

I heard(more like "read", actually) people talking about using Gallivm3D's llvmpipe as a fallback option in case your gpu can't do adequate acceleration(for whatever reason), but, at the moment, it doesn't work and you'd still need a rather powerful cpu, I guess. As for what exactly needs acceleration, I don't really know. I hope just a few effects that can be disabled. I mean, come on, even Windows lets you disable its stupid visual effects, but gnome doesn't? That'd be ridiculous!

A look at GNOME Shell

Posted Jun 10, 2010 18:26 UTC (Thu) by drag (subscriber, #31333) [Link]

> I do understand that they are using a generic engine (Clutter) for this which can do lots of other fancy things that won't work as well without acceleration, but surely this sort of edge case could be detected somewhere in the stack and fall back and work nicely even without acceleration.

I don't think it's worth it for a forward looking project to care about stuff like that.

The GPU is part of modern PC architectures. Just as much as your processor, memory controller, Sata controller, and so on and so forth. For Gnome shell to take advantage of it to accomplish it's goals just means that they are writing efficient software.

For fall-backs you will need to use software rendering pretty much no matter what. It's still somewhat common to have real 2D acceleration and that was used for composition in the pre-mutter version of Metacity, but that is rapidly going the the way of the dodo. GPU is the only 'acceleration' that is available going forward and it's easier/better to use a standard API to take advantage of it.

Software rendering of OpenGL should technically be OK, but the Mesa software rasterizer is really shitty and gives extremely poor performance. the LLVMpipe-based software rendering should be sufficient (even getting games like Unreal Tournament 2004 playable on very fast processors), but the API not complete enough yet to support clutter.

A look at GNOME Shell

Posted Jun 11, 2010 2:36 UTC (Fri) by k8to (subscriber, #15413) [Link]

It's worth limiting compatability if there's either no need or huge wins.

For an infrastructure product, there is need. And I don't see any huge wins.

A look at GNOME Shell

Posted Jun 11, 2010 14:22 UTC (Fri) by jond (subscriber, #37669) [Link]

This is a good rationale if the objective is to only target modern systems and that modern systems are correctly described as having a supported GPU. Unfortunately, I frequently make use of virtual machines these days, or systems where the GPU is not supported well (many modern GPUs, nvidia stuff, older ATIs, intel poulsbo, etc.), so these axioms do not apply to me. Which means that the future of GNOME is not my future, and that's unfortunate.

I can't really see many end-user wins, either.

A look at GNOME Shell

Posted Jun 14, 2010 21:50 UTC (Mon) by aigarius (subscriber, #7329) [Link]

Could, maybe, working over a VNC connection or on a remote X terminal be a good reason?

VNC connections are very, very common for remote administrative assitance and remote X terminals are what largest school deployments use to allow dozens of students to connect to one powerful X terminal server.

If GNOME Shell becomes unusable over a remote X of VNC connection, then it will be of a very limited use and likely fail as a generic replacement for Gnome panel.