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Comment: Re:c++? (Score 2) 407

I'm not sure that's really fair to Obj-C. Another way to explain the differences would be to say that Obj-C comes from the Smalltalk family of OO languages and C++ comes from Simula.

Smalltalk-family languages (eg. also Ruby, Swift, etc.) have late binding: you can join up things at runtime. This is great for GUIs, many common patterns become far easier. Simula-family languages are much more rigid. Almost everything is known at compile-time, so it's safer, but the rigidity makes some things harder to implement.

Writing a GUI in plain C++ is very painful, so all toolkits (that I can think of) add a late binding mechanism. Qt, for example, has signals and slots. Seen from this angle, Obj-C is something like Qt, but with the signal/slot mechanism made part of the core language and syntax.

Comment: Re:just want I wanted! (Score 2) 307

by jcupitt65 (#48958091) Attached to: Microsoft Announces Windows For Raspberry Pi 2

The r-pi has an accelerated desktop now, thank goodness. It was all software on a dumb frame buffer at launch, but those days are far behind us.

Who knows, maybe Wayland support will come soon, we can hope.

a href="http://www.raspberrypi.org/preview-the-upcoming-maynard-desktop/">http://www.raspberrypi.org/preview-the-upcoming-maynard-desktop/

Comment: Lawrence Lessig on this (Score 3, Informative) 495

Pre-2000, the US had "open access", meaning that cable owners had to sell use of their infrastructure. This made it relatively easy for startup ISPs to enter the market: every time you sign up a customer, you just need to buy time on the extra bit of cable you need to serve that person. Almost every country in the world uses this regulatory model.

Under intense pressure from lobbyists the US changed to a closed model in 2000. Now cable owners are also ISPs and have exclusive rights to the bits of wire they own. There are only a few ISPs, it's very, very expensive for anyone else to enter the market, and they can charge what they like, not only to customers, but upstream as well, as we're now seeing.

tl;dr: this is a failure of regulation.

Lessig talking about this:

http://blip.tv/lessig/america-s-broadband-policy-3505079

Comment: It's lightfield, it is holography (sorta) (Score 4, Informative) 171

by jcupitt65 (#48873423) Attached to: Hands On With Microsoft's Holographic Goggles

It's not using simple stereo screens, they have lightfield projectors:

Project HoloLens is built, fittingly enough, around a set of holographic lenses. Each lens has three layers of glassâ"in blue, green, and redâ"full of microthin corrugated grooves that diffract light. There are multiple cameras at the front and sides of the device that do everything from head tracking to video capture. And it can see far and wide: The field of view spans 120 degrees by 120 degrees, significantly bigger than that of the Kinect camera. A âoelight engineâ above the lenses projects light into the glasses, where it hits the grating and then volleys between the layers of glass millions of times. That process, along with input from the device's myriad sensors, tricks the eye into perceiving the image as existing in the world beyond the lenses.

http://www.wired.com/2015/01/microsoft-nadella/

They track eye movement and adjust for that as well. I think you need the lightfield stuff so that the eye if forced to adapt focus for different distances, it's a depth cue that Oculus don't have.

It'll be interesting to see what frame rate and latency they achieve. It sounds like they have a lot of hardware in the headset, so it could be quite good. Plus they only need to render the bit right in the centre of the field of view at high quality.

Comment: Re:Why don't they ever try to "link" good stuff? (Score 2) 222

by jcupitt65 (#48607623) Attached to: Linking Drought and Climate Change: Difficult To Do

The temperature graph in that article is not very useful. It ends in 1850, before most of the modern warming, and in any case it's only the temperature for Greenland, it's not global temperature.

The Wikipedia page on Paleoclimatology is probably better:

http://en.wikipedia.org/wiki/Paleoclimatology

They have this graph for the global temperature for the last 10,000 years:

http://en.wikipedia.org/wiki/Paleoclimatology#mediaviewer/File:Holocene_Temperature_Variations.png

Comment: Re:Too weak because humans are not the cause (Score 1) 145

by jcupitt65 (#48456205) Attached to: Prospects Rise For a 2015 UN Climate Deal, But Likely To Be Weak

I think all the solar activity graphs look like that, they are based on the same satellite data. For example:

http://upload.wikimedia.org/wikipedia/commons/0/0d/Solar-cycle-data.png

How can increased solar activity be causing global warming if solar activity is not increasing? Isn't it more likely that the huge increase in CO2, a strongly-warming gas, is the cause?

Comment: Re:Too weak because humans are not the cause (Score 1) 145

by jcupitt65 (#48456175) Attached to: Prospects Rise For a 2015 UN Climate Deal, But Likely To Be Weak

HadCRUT goes back a little further, 1850:

http://www.cru.uea.ac.uk/cru/data/temperature/HadCRUT4.pdf

There aren't sufficient historical records to go back much further with direct measurement. You have to start relying on proxies, like tree measurements and ice cores.

Comment: Re:Too weak because humans are not the cause (Score 1) 145

by jcupitt65 (#48448289) Attached to: Prospects Rise For a 2015 UN Climate Deal, But Likely To Be Weak

It is warmer now than it's ever been in modern times, according to the people who try to measure global temperature. Here's the NOAA global temperature since 1880:

http://www.ncdc.noaa.gov/sotc/service/global/glob/201410.gif

I realise that it's horribly cold in a lot of the US at the moment, but globally the world is very warm.

Comment: Re:Too weak because humans are not the cause (Score 1) 145

by jcupitt65 (#48447601) Attached to: Prospects Rise For a 2015 UN Climate Deal, But Likely To Be Weak

Are you sure? Here's the usual solar activity / climate graph and there's no clear correlation between the Sun's activity and temperature, but a very obvious link to CO2.

The article you link shows how cosmic rays can seed cloud formation, which may well be correct, but I don't think there's any evidence of the next step, increased temperature.

Comment: Re:Lucky sods (Score 1) 334

by jcupitt65 (#48340687) Attached to: Americans Rejoice At Lower Gas Prices

That's only the figure for the national road network, ie. motorways and some A roads (but not all, I think?). Local authorities spend bucketloads of money maintaining minor roads, more than enough to wipe out the direct taxes motorists pay.

Or that was all true last time I looked into it, perhaps things have shifted since.

The price one pays for pursuing any profession, or calling, is an intimate knowledge of its ugly side. -- James Baldwin

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