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Comment: It's their business model. (Score 3, Informative) 304 304

When you expect to get most of your revenue from selling apps in the iStore - it's essential that people are unable to get apps for free via fancy web pages.

Hence, iPhone doesn't support WebGL for doing fancy 3D graphics on a web page - if it did, people would write cool games in HTML/JavaScript/WebGL and monetize them directly without having Apple take 30% of the revenue and "approve" their product.

Is this because Apple can't support WebGL? Hell no! The browser actually DOES contain code for WebGL, but it's disabled...UNLESS your web site signs up to display Apple-provided advertising which case, WebGL works great!

Safari uses the exact same core rending software ("WebKit") as Chrome - so it can trivially support everything that Chrome supports - it's really just a matter of Apple deciding to deliberately cripple the browser to prevent people from providing apps for free.

Comment: Because it should never happen. (Score 1) 1067 1067

Whenever you divide by zero, the problem ISN'T the division - it's the previous code that either assumes that dividing by this number will produce a valid result, or is doing something wrong in turn.

Checking - and somehow kludging - a divide by zero does nobody any good. You have to ask WHY you're dividing by zero and what it should mean.

I *want* divide by zero errors because they inform me that I'm doing something wrong elsewhere.

(And even if you wanted to kludge it - returning a very large number would be a better choice than zero...but don't do that).

Bottom line - if you're doing lots of div0 tests then you're doing something wrong in many other places!

    -- Steve

Comment: Re:did the tech exist in 2010-12? (Score 1) 122 122

HMD's have been around since LONG before there were 3D graphics on the PC at all. They'd been used (for example) on military flight simulator back when you'd need a million dollars of mainframe hardware to generate a 3D image. I very much doubt that any of this tech is actually new. Probably someone like Evans & Sutherland were the first to do it - and they had 3D graphics back in the late 1970's. I doubt that much of the general concept is still patentable - so this argument is probably over some kind of small feature.

Comment: An infinite number of possible answers (Score 1) 496 496

Consider this...suppose you are just over a mile from the SOUTH pole. You walk a mile south - and now you're maybe a hundred feet from the South pole. Then you turn west and start walking...around and around in a tiny 100 foot radius circle centered on the pole. When you've finally clocked up a mile - you turn and head North again...where do you end up?

Well, the answer depends on the exact circumference of the circle that you walked around. Generally, you'll end up someplace very different from your starting point...BUT if that circle is an EXACT sub-multiple of a mile - then you'll end up precisely where you started.

So...the North pole is clearly NOT a unique answer.

Furthermore - the north pole is only ONE answer. My approach reveals an infinite number of possible answers:

1) You could have started ANYWHERE that's at the exact right distance from the pole - so anywhere on that circle will infinite number of starting points will work.

2) Note that ANY exact sub-multiple of a mile will do - so with mathematical precision, there are an infinite number of sub-multiples of a mile - and hence an infinite number of distances from the pole where you could have started.

Truly - the "North Pole" example exhibits very little lateral thinking... if that was your answer then you **FAILED** the Musk test...which (I'm pretty sure) is the whole point here.

The original version of the story is that a hunter walk a mile south, a mile west, shoots a bear, then walks a mile north to return to his starting point. What color was the bear?

Since there are no bears at the south pole - and only polar bears live anywhere near the north pole - then the north pole is the right place and the correct answer is "WHITE!"....but Musk isn't asking *that* question...he's trying to trick people into jumping to a false conclusion without stopping to think about it.

    -- Steve Baker

Comment: It is tough though. (Score 1) 353 353

I don't know about you - but there are two parts to my job...thinking and doing.

The doing part is easy enough to segregate...If I'm sitting at my desk at work "doing"...typing in code, debugging, documenting, etc - then clearly that belongs to my employer and I have no right to be "doing" anything that I'm going to have control over outside of work.

But thinking is near impossible to segregate. I may well be thinking about solutions to my employer's problems as I commute, or as I'm fritzing around with something else at home...and it's impossible not to have an idea for an outside-work project pop into your head while you're trying to come up with a solution to something that's work-related.

In my opinion, the inability to segregate work-thinking from home-thinking means that I shouldn't try. In my mind, I'm paid for the 'doing' part during office hours - and whatever 'thinking' is required in order to get the 'doing' done. 'Doing' that gets done on my own time is mine - as is whatever thinking went into making it happen. When I think of something that relates to my job - it belongs to them, even if I come up with it at 4am in a flash of dream-inspired wakefulness. And if I come up with something that would make a great off-time project while I'm waiting for my code to compile at work - then that's my idea and it's nobody's business when and where I came up with it.

The only requirement to make that work is a clean separation between the kinds of things I'm paid to do and the kinds of things I do for myself - but since "a change is as good as a rest", there is a natural tendency for me to do very different things in my off-time anyway. If you find that you have a fuzzy grey area in there - then you'd better lawyer-up and make sure everyone has a crystal clear idea of where the "doing" boundaries lie an that the "thinking" boundaries don't exist.

Comment: Unity3d isn't exactly free. (Score 1) 125 125

There are a significant number of 'missing features' in the free version of Unity3d...for example, render-to-texture. That's a pretty serious omission for any kind of serious software development - so the $1500 (or $75/month with a 2 year commitment) is necessary if you are really serious about game development. In a typical game company, $1,500 is roughly the salary of one programmer for a week. So over the life of any reasonable commercial game, the cost of buying a full license for each worker is essentially negligible.

What the free versions do is to enable indie studios to grow to the point where they can afford to pay for a game engine - and to get amateur game developers to grow interest, loyalty and expertise in a particular free engine that will hopefully translate into sales of the professional version when they become paid game developers in the future. But there are enough annoying road blocks that even an amateur developer may be tempted into buying (or renting!) the full version after running into a few of them.

It's a good model, and I hope it grows and continues.

    -- Steve

Comment: Like Voyager's golden record? (Score 2) 169 169

100 years isn't so long. They people who open the container will almost certainly be able to read instructions - and probably have reasonable technology to access the contents. But maybe they don't care enough to go to a lot of trouble to do it? It's very likely that the images you store will still be easily accessible in the future.

If you don't think they'll go to very much trouble - then you should provide them with the means to replay the data as well as the data itself. There are plenty of small video players (like a cheap digital camera or an MP3 player with video capability) - so long as you pack them appropriately and protect them from crazy temperature variations, they should last a long time in storage and still work at the end. Provide written instructions on what power requirements the machine has - and what buttons to push to access the content.

But quite honestly - there is unlikely to be anything in the data you provide that won't be accessible by then.

I would stick with physical objects that would be of historical interest, personal items - a snapshot of the times when the capsule was buried.

Maybe it would be worth trying to find people who've opened capsules like this - and ask them what was found to be most valuable from the contents?

    -- Steve

Comment: Apple Watch vs Pebble Time? (Score 3, Informative) 529 529

I didn't catch the Apple announcement - but I wonder how the Apple Watch compares to the Pebble Time that's doing huge $$$ on Kickstarter right now?

From what I can see:

* Pebble is *way* cheaper.
* Pebble has a 7 day battery life (kinda beats 18 hours!)
* Pebble works with both iOS and Android, so if you ever want to change your phone, you won't have to change your watch.
* Pebble allows anyone to develop & ship apps without a fee.
* Both scheduled to ship about the same time.

I'm sure there is more to it than this than that...but why on earth would I buy the Apple watch?

Comment: Easy to understand - impossible to solve. (Score 1) 164 164

I've worked with VR helmets since the 1980's in flight simulation.

The problem is simple: Your eyes use two mechanisms to figure out distance - the degree to which your eyes have to point in different directions in order to fuse two images into one - and the degree to which the lens has to be stretched or squished to pull things into focus. Every VR helmet ever made gets the first thing right - and completely fails at the second thing. No matter what optics are used, no matter anything - you're focussing at the same distance over the entire visual field, regardless of virtual distance.

When our brains look at two inputs that should yield the same results - but they don't - we assume that something is malfunctioning, and we get sick.

Same deal with seasickness when the inner ear says one thing about the motion and our eyes tell us something different.

So - you need some kind of insane computer-driven lenticular display where every pixel has a lens that focuses that light at an appropriate depth for the 3D content at that point. Such things don't exist...and that's the only thing that'll make this problem go away.

All of the recent people to try to fix this are amateurs who just started looking at it - look back at the research done by the old flight simulation companies like Link, Singer and Rediffusion - and the decades of research on this subject done by AFRL (the Air Force Research Labs), the US Navy and NASA.

WIthout solving the focus problem, we're doomed to another cycle of dizzy, puking customers.

Worst of all - US Navy research shows that after a protracted time in one of these VR rigs, it's dangerous to go out and drive a car or fly a plane - their pilots aren't allowed to fly within 24 hours of being in a simulator.

    -- Steve

Comment: Re:Cash is king in my world (Score 2) 230 230

Because a smartphone is something that nearly all of us already have for other reasons (an ultra-portable computer, a phone, a GPS, a music player, a watch, a camera, a flashlight, a gaming system, an email reader, an ebook reader, a video camera, a transistor radio...all in one handy unit) it's not $300 to $500 + $40..$80/month more than most people are already spending, it's $0 more.

Because not having a credit/debit card means that it's hard to shop online, and you have to make frequent trips to a "bank" to pull cash . Actually, if you pay your credit card bill on time and in full, most credit cards cost $0 too...and a debit card probably does everything you need at $0 also.

So your dinosaurian perspective isn't clever - it's just antiquated.

Comment: I actually have some sympathy for the utilities. (Score 5, Insightful) 374 374

The thing is that with net metering, solar power users are effectively using the grid as a giant battery that they charge up during the day and discharge during the night.

They aren't paying for use of that battery, but the utility company is still expected to maintain it. If you're not buying electricity from them, then they are providing that service for no pay - and that's not a sustainable business model.

It's not a problem when only a microscopic percentage of users have net-metered solar power - but if a large number of people do it, then there could be a huge problem...and if there is ever more daytime solar power being generated (eg on cloudy days in winter) than is being consumed - then there will be a GIGANTIC problem to resolve - and that's going to require massive investments that they won't have.

So I do have *some* sympathy for them. They should, at some point, be allowed to charge for the service of effectively storing your power for you...although we're not remotely close to that point right now.

Comment: MediaWiki. (Score 4, Interesting) 343 343

My wife and I use MediaWiki! Seems kinda silly - but you can configure it to accept all kinds of file types - and you have all of the nice stuff like discussion pages and categories to help you to organize them.

The huge advantage is that it's insanely easy to use. Super-light on features also...but,'s a thought, right?

    -- Steve

Steve Jobs said two years ago that X is brain-damaged and it will be gone in two years. He was half right. -- Dennis Ritchie