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Comment Re:I guess they realised... (Score 1) 130

I disagree. Wayland is essentially a subset of what X11 can do. It is based on sending messages over a unix domain socket and sharing buffers. This is exactly what modern X clients also do. This is no surprise: It was designed to support exactly what is needed for modern clients and no more with the explicit goal to get rid of everything else. But it does not add anything which you cannot also do in basically the same way with X.

Trying to say that just because it uses sockets makes it like X11 doesn't make it so.

This is true. This is about retaining backwards compatibility.

Right... so we must maintain backwards compatibility for barely used functionality even when it impacts on performance in the every day use case. And even when you can have backwards compatibility by running Xwayland or by running X11 without Wayland while everyone else enjoys a better experience.

Extensions are nice way to make modern rendering possible without breaking backwards possibility. "fool" "2D-centric" "1980" is just FUD to make it sound bad, but X supports modern applications just fine. You have no technical argument.

It's not FUD, it's true. X11 is from an age where the screen screen was a bitmap and every window to be a region in that bitmap. When you moved one window over another the server would throw out damage events and every client would repaint their areas. And x, y coordinates for mouse moves were simple transforms from screen to window coords.

This model is totally discordant with a modern compositing desktop. X11 has gained a compositor extension which is hacked into this model but underneath it still thinks the same way. So the compositor must duplicate state from X11 except sometimes windows might be scaling or otherwise not where X11 thinks they are. So all the x, y mouse coords are screwed up and don't map properly. Oh and because the compositor is a separate process it means extra context switches in and out of the damage event so the server can preserve its worldview.

In Wayland the compositor, server and window manager are the same process. So the state isn't duplicated or mismatched and compositing does not require a context switch.

Because modern clients work essentially in the same way on X as on Wayland,nothing is slower or less efficient. Just because some API is based on an extension or not doesn't make it faster or slower. This is simply FUD.

Wrong. X11 incurs more context switches than Wayland to recomposite or to handle input messages. There is a simple diagram that demonstrates this point.

No. Mostly, it will break backwards compatibility, and remove features. The few kilobytes on unused drawing API in X11 will not make any noticable different on desktops (or mobiles) with gigabytes of ram.

Run X11 over Wayland if you want backwards compatibility or start the desktop with the X11 backend. There's no reason your esoteric needs should impact on the experience everyone else suffers from. And thankfully that reality will soon be realized.

Comment Re:And this is what that means: (Score 1) 279

Has adblock "won". I think it's better to say its winning, but the more people use it the more likely that sites will develop effective countermeasures.

It would be relatively straightforward to circumvent adblock. All it requires is that the ads be delivered from the same domain for urls used to fetch the content and ads cannot be separated by pattern matching. This might be too much effort for some smaller websites but I see no reason that bigger sites couldn't do it. e.g. 3rd party advertisers could offer some kind of webapp that runs inside the host's DMZ and works in conjunction with some kind of frontend url resolver that sends requests one way to fetch content or the other for ads (and ad clicks) so they both appear to originate from the same host.

It would also be simple to block the adblockers by looking for page elements which should be there but aren't and blocking the user until they disable ad blocking on the site. Some sites already do this and more might do it in time.

Comment Re:I guess they realised... (Score 1) 130

The Wayland API is nothing like X11 except in broad concepts that all display / input APIs share - listening for input events, connecting to a display, creating a drawing area and so on. It's just that Wayland's map onto modern concepts such as GPU surfaces and compositing so that rendering is as efficient as possible.

As for the primitives, nobody has ever said they slow modern clients. The point is that clients don't even use the primitives any more and its the same story applies for most of the rest of X11. It has a 1980s 2D-centric, damage based view of the desktop and extensions are used to fool it into supporting surfaces and composition. But those extensions are workarounds which are design compromised by the architecture and so they are slower and less efficient than they would be.

Hence the push for Wayland. It will ultimately lead to a more lightweight and responsive desktop. Fedora Core 23 will be released soon and GNOME 3 should be feature complete for Wayland. And 24 might flip the switch and make Wayland the default. It doesn't stop people using X11 if they want so I don't see the problem.

Comment Re:I guess they realised... (Score 1) 130

X11 isn't perfect. Nobody's ever argued that. It's just nobody's really asking for a replacement, and if they were, they wouldn't be asking for Wayland. X11 is an extraordinary piece of technology, it takes some gal to claim everyone should just throw it out and replace it with a ground up rewrite that adds no new features and doesn't support the major features X11 is famous and loved for.

I think you'll find lots of people are asking for a replacement, starting with the people most familiar with X11. And more generally anybody who wants Linux to be able to host a modern, responsive desktop experience without suffering the latency and other bottlenecks of an arcane and mostly obsolete architecture for no reason whatsoever.

Comment Re:I guess they realised... (Score 1) 130

Exactly. X11 was designed for a different world where there was clipping, damage, rendering primitives, immediate rendering etc. It doesn't have any concept of compositing or GPU surfaces and thus a raft of extensions have appeared to support those things. But of course they're still hampered by a brain damaged pipeline which still thinks in the old way and they are constrained by.

Comment Re:VR is going to land with a thud (Score 1) 174

I play Stumovik Cliffs of Dover which has some amazing cockpit models and I can't help but think what it would be like if I was actually looking around with my head instead of with some stupid hat control. But sims are a niche. Not everyone likes flying planes around (or trains, trucks, tractors etc.). And even of those that do, only a fraction stump up for a stick let alone a peripheral costing $350 and requiring high end hardware.

So I don't see that sims would save the tech. Nor do I expect Oculus would be happy if it launches with great fanfare and ends up being mostly used by someone driving a tractor on a virtual farm.

Comment VR is going to land with a thud (Score 4, Insightful) 174

There is no denying VR sounds cool. In some cases it might actually be cool - I'm thinking particularly of racing / flight / space sims where you sit in a cockpit and the range of movements in game roughly correspond to real life - you sit in the game, you sit in real life, you have buttons and controls in the game, you have buttons and controls in real life.

But for other kinds of game I really don't see the benefit. Yeah it could be used for first person shooters (for example) but then the game has to somehow reconcile a person running, spinning, jumping, aiming, shooting, standing, crouching and throwing stuff to someone in real life sat on a couch. It's likely that it will be extremely disorientating and puke inducing.

And aside from FPSs what can we expect? Probably some lame jump scare horror games. Probably some table top style games. But nothing that particularly justifies the experience. I bet most games will work as well if not better in 2D.

The strange part is there are at least 3 major efforts to do VR plus a number of smaller ones and they'll end up cannibalizing the market for what it is. It's going to be a bloodbath.

Comment Re:700 ms latency, though... (Score 1) 58

And the latency is because the the satellites are in a geostationary orbit a horribly way long way away - signals having to go out 35000km out to the satellite and back again to some base station.

The other alternative is lots of satellites in a low earth orbit, with one coming into a range as another one leaves and some kind of data relay mechanism for sending data to a base station. A more complex solution but latencies would be much lower and it would probably scale better. The same satellites could even be used to service parts of Africa and South America.

Comment Of course it increases security (Score 1) 317

Chip and pin devices are more secure than magnetic stripes in a number of ways.

Buying something with a magstripe normally involves swiping the card in a reader and scrawling a signature onto a screen. Theoretically the cashier might ask for ID or compare the signature to the card but they rarely do. And the cashier might even be cahoots with the thief, knowing the card is stolen and not do any check at all. On top of that the merchant might store transaction details insecurely, or their software may be hacked. And in some scenarios such as bars & restaurants, the card might be taken from the sight of the customer which increases the risk of it being skimmed. All of these are major vulnerabilities that thieves have been known to exploit.

A chip and pin reader means that the card holder must authenticate themselves before proceeding. That stops someone from picking up a card, or cloning one and being able to use it without the pin. And authentication is to the payment processor and not to the store or cashier so it's not possible to bypass this check. It also means the store never captures the credit card info (they only get partial info and some payment authorization code) so hacking the store does not put details at risk. And chip & pin devices are portable so payments in bars & restaurants can be made in the presence of the customer so they are less likely to be swiped.

So yes it closes some very obvious security flaws. Is it perfect? Of course not, but it's a hell of a lot better than a magnetic stripe. It's a damned shame that it's taken the US so long to even switch to chip and pin. The next step would be to get rid of the magnetic stripe altogether but I expect we can look forward to years of lobbying by ATMs and banks how this couldn't possibly be done.

Uncertain fortune is thoroughly mastered by the equity of the calculation. - Blaise Pascal