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We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

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Comment: Re:Or maybe... (Score 1) 417

by ShakaUVM (#49315293) Attached to: How 'Virtual Water' Can Help Ease California's Drought

>... don't plant water-intensive crops in a drought zone? Naaa, that would require actual understanding of the situation. As it is, the only thing that will help is all those water-wasters going bankrupt. Reality is merciless.

I know several almond farmers here in the Central Valley.

Contrary to what you and TFA think, they've been engaging in very significant water cutbacks on their crops for years now, testing to see how little water they can get by with needing. I think they're currently at about 10% of the water that they were using a decade ago. How? They have water sensors in the soil, making sure they don't overwater below the root line, that wirelessly report back their findings to the farmer, who can then turn on a very small amount of water as needed to trees that are bone dry. They've also found the trees are a lot more drought tolerant than anyone thought, and can get by with less water than is recommended.

Overall, their water efficiency is about 90% currently, with the remaining 10% waste being hard to get rid of, as its used for things like backwashing dirt out of filters and the like.

Farmers here aren't these naive "water wasters" as you so ignorantly put it, and have a much better "understanding of the situation" than you do.

Comment: Re:Sim Sickness (Score 1) 164

>In my experience it's not just a head tracking issue. Just the feeling of seeing your avatar walking around in the virtual world, while your real body is stationary, was enough to cause nausea in a lot of people.

Well. You shouldn't be seeing your own avatar. Other than that, there's nothing inherently sim sickness-causing about moving around a world. You could be a tank or an airplane or a person as far as your inner ear is concerned. What *does* cause a massive amount of nausea is when you are in a FPS and you're constantly snapping your neck around to see if someone is behind you, above you, besides you, etc. But that's not necessarily sim sickness - you'll get nausea in real life if you made the same head movements. You'll also wear our your neck muscles, which is another big issue... once VR headsets weigh past a certain amount, they cause neck problems.

Comment: Re:Sim Sickness (Score 1) 164

>Actually most of what you describe is solved. the head tracking latency is a solved problem, or at least well understood what is required to remove it as a cause for sickness

Well. A problem can be (and is) well understood without necessarily having a good solution for it.

I recall talking to Michael Abrash about how we quasi-solved it back in the day when he asked about it a couple years ago. And he was working on VR for Valve. So maybe, yeah, they solved it. But at the time he thought it was pretty much impossible to do right.

Comment: Re:Sim Sickness (Score 1) 164

>In your experience would you say that people can adapt to sickness caused by VR over time? Does it vary?

For some people, yes. They get used to it.

For me, I actually got more nauseous over time. But we also moved between software products and switched the prediction software, which was also part of it.

The interesting thing is that the people who are most in tune with their bodies get the most sick. My boss had a friend who was a pole vaulter who put it on and got instantly sick. Whereas people who aren't really physical have an easier time with it on average.

Comment: Sim Sickness (Score 5, Informative) 164

by ShakaUVM (#49191347) Attached to: Developers Race To Develop VR Headsets That Won't Make Users Nauseous

Source: I worked in VR 20 years ago for a defense contractor.

Sim Sickness is caused by a disconnect between what your eyes see and what your inner ear is telling you is happening. Your eyes are extremely sensitive to latency. If you snap your head quickly, even a small lag will cause a certain percentage of people to get nauseous. Having a fast and accurate motion tracking system is crucial, but you also need to have an extremely fast rendering engine and a headset capable of updating quickly as well. Motion prediction helps, also, but does not eliminate the problem. As does making sure your program doesn't require you to spin around a lot.

We can only put up with the horribly slow latencies on flat screen displays because they're not attached to our heads.

Comment: Re:Lots of weird crap coming out of Congress latel (Score 1) 517

by ShakaUVM (#49191301) Attached to: White House Threatens Veto Over EPA "Secret Science" Bills

>First, there is no reason to believe that list is exhaustive. According to the page itself, it is "a partial list of the chemical constituents in additives that are used or have been used in fracturing operations."

It a comprehensive list provided by the major fracking companies as to the compounds used in the last five years.

> It was only released in 2011 in response to a congressional investigation, having been held secret for 60 years.

Yeah. Four years ago. And yet you're defending people who made these claims:

"Like the fracking example parent mentioned; nobody is able to research their methods and the compounds used, because trade secrets"

"There is no scientific literature on how nasty fracking fluid is (blatantly not just inert chemicals) because the companies using it refuse to disclose what's in it."

My purpose in posting here is to note that these claims are, in fact, factually wrong.

>Perhaps you are willing to have your dinner grown next to a factory that can hold its chemical waste secret for 60 years, and then be unable to regulate that waste for another few years or decades, waiting for someone to bother to measure their health effects.

Clearly, your logic is, "Well, ShakaUVM corrected a factual error in two posters, therefore he must hate the environment and want everyone to get cancer."

Perhaps you should think that through a little more next time.

Comment: Re:Lots of weird crap coming out of Congress latel (Score 1) 517

by ShakaUVM (#49191261) Attached to: White House Threatens Veto Over EPA "Secret Science" Bills

>The point is they were widely being used before being scrutinized.

No, the point is you watched Gasland back in 2010, and thought your claim was still true today in 2015.

>Some of the compounds listed in that report (which I don't think claims to be exhaustive) are known or suspected carcinogens.

No kidding. I didn't say they were safe. I said your claim that nobody knows what is in them is wrong.

Comment: Re:Lots of weird crap coming out of Congress latel (Score 1) 517

by ShakaUVM (#49191241) Attached to: White House Threatens Veto Over EPA "Secret Science" Bills

>Read: http://www.reuters.com/article... [reuters.com]

Welcome to Slashdot, where a vote by a state legislature gets moderated up higher than a congressional report detailing all the chemicals used in fracking.

>http://www.newsweek.com/theres...

Or where a person tries to cover up the fact that he got proved wrong because he hasn't checked his facts since Gasland came out in 2010 by stating, "Well, there's still more stuff we can know."

Shall we take a peek at what you originally claimed? Ah yes - "because the companies using it refuse to disclose what's in it."

Bullshit. And you know it's bullshit. Don't try to cover it up by saying, "Well, we don't know *everything* about all the chemicals". This is not the same, and you know it.

Comment: Re:Lots of weird crap coming out of Congress latel (Score 1, Informative) 517

by ShakaUVM (#49187477) Attached to: White House Threatens Veto Over EPA "Secret Science" Bills

>Like the fracking example parent mentioned; nobody is able to research their methods and the compounds used, because trade secrets.

You mean the compounds so secret that there's a wikipedia page listing them all?

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

They were disclosed back in 2011.

Comment: Re:C++ is probably a little bit better (Score 1) 407

>Debugging has always been a problem. One of the other posts here suggested using CLANG because of it's better error reporting. Thats right now, after 25 years. Let's face it, C++ is legendary for the obscurity of it's compile and link time error reporting. Beyond that, it's not like the run time debugging environment is any better. All that it supports is the kind of break point debugging that was in C. No value added beyond K&R.

This is true. I teach introductory computer science using C++, and one of the biggest hurdles for my students is understanding the error messages from the compiler. Half the time they don't mean anything unless you already know what it's supposed to mean.

And that's before even getting to templates. Once you get into templates... /shudder. The error messages are insane.

I tried compiling the rather simple boost program from the "getting started" section here: http://www.boost.org/doc/libs/...

Without the proper library linked in (i.e. just doing a "g++ test.cc"), I get 38 lines of vomit that look like this: .text._ZN5boost11 basic_regexIcNS_12 regex_traitsIcNS_16cpp_regex_ traitsIcEEEEE6assignEPKcS7 _j[_ZN5boost11basic_ regexIcNS_12regex_ traitsIcNS_16cpp_regex_traitsIcEEEEE6assignEPKcS7_j]+0x22

Comment: Re:Just release a special edition Bluray (Score 1) 133

Detaching boosters does not provide boost.

They ran out of fuel, and then just barely escaped the falling into the black hole in the slingshot maneuver by disconnecting the dead weight, which magically accelerated backwards propelling the spacecraft it detached from magically into Mars orbit.

There's artistic license (like the drawing of the wormhole, which is whatever, it doesn't bother me), and then there's a landing shuttle which can magically boost in and out of a .99999C gravity well without ill effect or expending much any fuel at all, and yet magically has to expend all of its fuel supplies to slingshot around the black hole, and then accelerates further by detaching boosters, and all sorts of dumb shit like that.

Comment: Re:Just release a special edition Bluray (Score 1) 133

>It's a movie. Most people don't care but for those sticklers, all they have to do is release a special edition that contains a "director's cut" of the film as well as a "science advisor's cut."

There wouldn't be much left, then.

As much as Kip Thorne and NDT have touted the science of it, anyone with even a basic understanding of physics would develop a severe allergic reaction from watching the movie.

No, Nolan, disconnecting an object travelling with you doesn't magically boost you out of a gravity well.

No, Nolan, there is no way to have enough delta-V to boost out of a .99C gravity well.

Kip Thorne has defended the notion of a stable planet right next to the event horizon of a black hole, and maybe he's right, but horrid mistakes like this are scattered throughout the movie.

Comment: Re:Not sure why this is on Slashdot (Score 1) 327

by ShakaUVM (#49036241) Attached to: Ask Slashdot: Panic Button a Very Young Child Can Use

>Pro-tip: When posting to Slashdot, or any other website, write your post in an off-line text editor, then cut-and-paste it into the textarea. That way if their buggy JavaScript, or you fat fingers, delete it, you can just re-paste.

OR you could just install Lazarus and let technology handle the grunt work for you.

http://getlazarus.com/

You are lost in the Swamps of Despair.

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