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Comment Re:Unregulated currency (Score 2, Insightful) 704

When buying, selling and trading bitcoins there are two things which make it work.

Exchanges, where you can buy or sell bitcoins to "normal" money.
Wallets, where you store your bitcoins.

Some sites are both (like mtgox) and others are only one (from what I can tell Flexcoin was a wallet, not an exchange).

When you buy and sell bitcoins at an exchange you tend to need to transfer money to them and have it sit in an account until you want to exchange it to bitcoins. (This is similar to buying tokens at a casino or something like that. You don't have bitcoins yet but your money is still on their server.)

Once you have bitcoins you can transfer them to a different wallet (which can be another site or just a digital file on your PC).

Both this and the Mt Gox case have a similar problem and resolution. Don't leave your money with people you don't trust. That is a good life lesson to learn, and hopefully it won't cost you too much. The same goes for putting a bunch of money into other shady businesses like online casinos and similar.

It seems like most people who are angry about how "obviously broken" bitcoins are just don't understand how they work. (And to be fair, most websites don't really explain it well either.)

You can still make a perfectly valid argument that putting your money into bitcoins can be a terrible investment. But the same goes for a lot of things. (Like the people who stocked up for food cans before Y2K.)

Comment Re:not Fun, but honest clip (Score 2) 104

I found that more reminiscent of Louis CK's rant on "Everything is amazing and nobody is happy". :-)

There are some valid points though, the screen door is an issue on the dev kits. Personally I find that after a while you don't think about it too much. It feels more like watching "the real world" with a net in front of your eyes than a low resolution screen.

That the current screen is a compromise is not really a surprise to anyone who has followed the project. They had to swap screens as they started to produce the dev kits, so they went with a 7" screen because that was the best they could get with respect to resolution and refresh rate. Unfortunately it leaves a large part of the screen area unused as it's outside what you can actually see through the lenses.

Comment Re:Hope they will fix the motion sickness problem (Score 1) 104

My experience is that for the best experience you really need a powerful graphics card. If you get lag you will get motion sickness. (Or at least I do.)

For that reason I think if you want to use a laptop as a real demo station you'll need a gaming laptop with a fast GPU. Ideally you'd want a desktop most likely.

It might be worth checking how many FPS you get on your setup. I believe you want at least 60 FPS.

Comment Re:Hope they will fix the motion sickness problem (Score 1) 104

I find that it depends a lot on the demo you are trying.

The included Tuscany demo is very slow paced and most people have no problem handling that. I think out of 30+ people I have demoed my dev kit to only two people have gotten sick from that. Games like HL2 is a lot worse though, and I'm not sure why. I think speed has something to do with it, but it might also be that the rather cramped settings you are playing in aggravates the problem of not tracking head position. (Basically, when you sway your head side to side the game world doesn't match. This effect is more noticeable on things which are close to you in the world.)

I have also found that a few demos I have tried have had noticeable lag. These make me sick very quickly.

Comment Re:Tripod (Score 1) 78

Movi (which this guy was apparently inspired by, he says so in the youtube clip at least) has an example movie shot by Vincent Laforet at Vimeo. (He's the guy that shot the first 5D mk 2 video as well.)

The Movi system is for professional use though, and it costs $15k so it's not exactly for people to play around with.

If you want to understand more about why a gimbal system is so cool then look at the behind the scenes video from the Movi demonstration as well:

Comment Re:Jorgenson is full of shit (Score 1) 339

I think you put the emphasis on the wrong part of the quote.

The point isn't that you can't learn programming by reading a book and experimenting.

The point is that this is not something everyone can learn (at least that way).

Those who are interested in computers will learn that way. But most people will not learn anything.

Comment Re:The best way to find programmers (Score 1) 260

Interview question #4: Justify why you didn't know that C++ can also do those things

The fundamental issue I have with C++ as a language is it has a "improv theater style" design where the answer is always "Yes, and...". A more sensible language tends to be designed with "No, because ..." answers to at least some features.

Comment Re:So... (Score 1) 154

Considering his main complaint is about replacing the users vision with that from a camera is moot I think it's fair to say that the skepticism is well placed.

Google Glass doesn't have a complete AR viewfinder. It's screen is only in the corner of your eye, so you don't have to look at it unless you want to.

And testing the effect he describes doesn't take any fancy equipment either. Just try walking around by looking through the viewfinder of your smartphone or compact camera. Even that is quite disorienting.

Comment Re:Where have I seen this before? (Score 1) 94

Considering that the two were on stage together at QuakeCon talking about this issues I don't think it's all that strange. ;-)

The Virtual Insanity session ( is well worth watching if you are interested in these things. As is Carmacks keynote from QuakeCon 2012.

Comment Re:It was not just hardware (Score 1) 94

I looked into this claim when the Oculus Rift was first presented (and the same references were made). BTW the experiments were funded by Sega as they were also looking into making a VR headset.

The only claims I could find are made by one guy. (Who I can't remember the name of right now, but he was involved in the Sega VR project.) And it seems like this is the only person to have said that there are medical problems with using VR. (IIRC he was also involved in the more recent scare that 3D TVs could hurt your eyes.)

The research results done for Sega VR were never published, they only said that it wouldn't be a good idea. (Not specifying if this was for medical reasons or that the VR experience just wasn't good.)

Palmer Luckey (the guy behind the Oculus Rift) has a sizeable collection of VR stuff already. And has apparently worked with some military VR stuff, so I'm pretty sure he knows what they are doing.

Comment Re:Invest in AR, not VR (Score 1) 94

Carmack, Abrash and Palmer Luckey talked about this during the Virtual Insanity session at QuakeCon (, And they point out that augmented reality is harder than VR for a few reasons.

The biggest ones are that your latency tolerances are much lower since you are comparing with reality. So any latency you add will be very obvious to the user as the things will seem to "float" on top of the real objects. Furthermore the way our eyes perceive depth makes it very difficult to completely fool the eyes that what they are seeing is real. Eg most systems today will cause you to focus at infinity. This works well enough in a VR environment, because everything is the same. But in a AR situation if you are looking at something you hold in your hand and replace part of it with AR then that part will be at infinite focus. So when you look at it it looks wrong. (It's similar to if you see a reflection in a screen, and you can consciously shift focus to the screen or to the object being reflected.)

You also don't need to completely fool the brain in order to get feelings of height and stuff like that. Even people who try Cave systems say that you get a feeling of falling if you jump of a virtual cliff.

And there are systems which actually do directly manipulate your sense of balance and movement. Look up galvanic vestibular stimulation (,

Comment Re:the real reason houses don't collapse.... (Score 1) 432

Yes and no.

I'd point out that modern computer programs are often extremely complicated when compared to other things. It's less like building a house as it is building an entire city at once. It's also worth pointing out that building houses usually has a lot more stable requirements and environments (the laws of physics), software is changed all the time.

And the final nail in the coffin for me is that we have tried building software like "houses" or other large scale engineering projects. They tend to fail. (See the waterfall method, or "Mythical man month".) Assuming that software engineers are not simply less intelligent than other forms of engineers I think it's safe to conclude that the same methods may not work.

Comment Re:I don't do a lot of programming (Score 1) 432

I was expecting your post to go "the most interesting programmer in the world" route with that start. Now I'm kind of disappointed. :-)

Regarding making diagrams and such... I find it depends on what kind of program I'm writing and in what language I'm writing it. If I'm working with low level stuff (like asm, or low level C) then I'd be a lot more inclined to diagram things first with quite a lot of detail. If I'm coding applications for phones I can usually do with making a rough sketch (usually starting with the first UI screens) and work from there quite free form.

Reuse is something I find I rarely do outright (unless I know that something will be used in multiple places). Modern IDEs make refactoring easy so my experience is that I'm better off doing that work when I need to. (Usually you will still have to adapt the code anyways because your new use will not match perfectly with what the old code did.)

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