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tfinniga

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While Fusion 360 does have many non-NURBS procedural surfaces, they definitely also have NURBS. Otherwise you wouldn't be able to import an IGES or step file.

Using a solids kernel with procedural surfaces can help many cases, as you keep the modeling tree around and can recompute portions at higher tolerance as needed. However that's just another cumbersome workaround to the fundamental problem that the math doesn't have clean solutions.

I think a big part of why this happens is that a lot of the fundamental math of CAD doesn't have good answers - everything is heuristics and approximations to within a tolerance.

You can get a simple NURBS kernel up and running in maybe 2 dev-years. But getting good heuristics created for all of the common edge cases is what takes the huge number of dev-decades, and what you pay for with one of the commercial kernels. You won't even know what the common edge-cases are until you start getting user reports of things failing, so you'll need to be doing this development with a large community of users.

There is no closed-form formula to tell how long a NURBS curve is. Offsets of NURBS curves are not NURBS curves. Likewise, intersecting NURBS surfaces produces intersection curves that are not possible to represent as NURBS curves.

So something as simple as a fillet is impossible to exactly produce in like 3 ways. Booleans then add the joy of topology to the mix. It's all heuristics and approximations and dirty hacks.

I'd heard people say that the architecture of a city is usually frozen in the time when it had the most money.

If you look at the skyscrapers and other buildings from Zaha Hadid, they're not Art Deco. UAE and other countries which are currently building out significantly aren't sticking just to Art Deco. London is interesting in that they've had money pouring in for a long time, and have an eclectic mix of large buildings.

Last year there were 29,000 categories that could be targeted. If an ad sales rep wanted to close a deal, how difficult would it be to add one more for recent burn victims, or people who recently bought a specific product?

From the links that m_ke posted, facebook already has ties to loyalty card information, so it's very possible that they didn't need to do any inference, they just had the data directly.

In any case, the main point is that facebook doesn't need to listen to what people are saying, it has a ton of other data streams that could explain the stories in the link.

Facebook is amassing a huge amount of valuable information on every member.

I disagree that the threat of outrage is sufficient to stop the information being used badly. For example, there is outrage against Equifax, but their cache of information has still been compromised. We have seen data leak after data leak from various companies. If a country's spy agencies want to go after the data, they have a lot of resources, from hacking to legislation to physical intrusion or coercion.

Add to that, it seems like Facebook doesn't institutionally care about privacy (probably because it is hard to explain something to someone whose paycheck depends on them not understanding it). For example, http://actualfacebookgraphsearches.tumblr.com has some very damaging graph searches. Or people who have been outed as gay by incomprehensible privacy settings.

Facebook is a sieve, and the reason to care about them having a lot of information is the same reason to care about privacy in general.

Right, like the example from Target. It is possible that facebook has access to a stream of Target purchases or credit card purchase information. I'd be 0% surprised if there was a data sharing agreement with credit rating companies.

Even if they just knew the price of the purchase, combined with the job (burn risk) and location data (traveled from work to nearest store with pharmacy during the day), it's possible that you might be able to infer a burn with enough accuracy to be valuable to advertisers.

Another issue of letting sellers glom on to the main product SKU listing is that the reviews are all over the map, and there's no way for a customer to tell which review came from which seller.

I bought some tripod mounts for a VR rig - some of the reviews said they were plastic, some said metal, some said the quality was good or bad, etc. I rolled the dice, and got metal ones that smelled so badly of gasoline that I couldn't keep them in the house. Ended up buying some name brand, that at least had predictable quality.

There are lots of things that Amazon could do to counter these issues. Just look at what they are doing for Prime and 'sold by Amazon' - there is a big checkbox when searching to only show prime-eligible items, and when looking at the list of sellers, amazon is shown prominently with different graphics. They could easily do the same things for verified owners of products, so that OEMs could sell on Amazon and customers could be sure they're buying a genuine article.

If it were truly an insoluble problem, why are there no 'Amazon Basics' counterfeits on the market?

Extreme Commuting 9 years ago

The first impact of self-driving cars will be much worse traffic. While ride-sharing and public transit are helpful, they are nowhere near as good as self-driving cars.

If you had a self-driving car you'd be able to set up a truly productive or relaxing environment, which you're unable to fully replicate on public transit. For example, stick in a mattress with your favorite pillow, add a shower, have a desk with nice big monitors, a webcam to take video calls, etc. Aside from just being transportation, a car is also a bubble of quiet, cleanliness, and personal security. It is a mini house on wheels, a portable locker, and a refuge.

And since you're not driving, who cares about the traffic?

Why not both?

MP3 is more widely supported than any lossless audio codec. Lossless compression enables the collector to keep an original.

Not everyone is a collector though - for them, MP3 is probably fine, and if they need a different format later they'll probably just stream, re-encode, or re-purchase, in order of likelihood.

I think it's a good exercise to do that kind of self-examination, to honestly evaluate situations which are morally ambiguous to various degrees, figure out where you stand and why, and plan what you would do when such a situation presents itself.

It's very likely that you might just go along with something in the moment, unless you've thought about it in advance and are able to recognize it.

When I was in grad school I knew a student who was almost completely amoral - not that has was evil, but it seemed like right and wrong never even entered into his decision process. For example, he decided that it might be profitable to write splog-creation software. He even brought in different outputs and did user testing in the lab, asking fellow students if they preferred output A or B, which had more believable testimonials, and if they were suffering from acne, which would they be more likely to buy from, etc.

It seemed scummy to me, but it took a long time for me to put my finger on exactly why. Wasn't it just another kind of advertising? It helped sell the acne medicine, which was a benefit to those that bought and sold it, right?

Your answers might be different, which is why it's good to think these things through for yourself. For me, what I came to was that the Google search engine is good, and it provides a lot of value by making it possible to find what you're actually looking for. The splogs where siphoning off some of that value, and giving it to that student.

They provided value to the student, but they made the internet worse for everyone else because it would be harder to find what actually worked well or was organically best. Basically a tragedy of the commons, and the result was a net negative - he destroyed a lot more value than he was able to capture, even though it was only a papercut from each person. It's much better to create more value than you capture, so the world is a better place for having you in it.

I think that kind of approach might be applicable here. Is Uber competing in a way that is beneficial to their customers, and therefore net positive? If they compete by trying to hobble or destroy Lyft that kind of sucks, but if they win by having a better product or a better approach to business, that seems more fair and results in a better outcome, a better world. Run faster, don't kick the other racer's ankles.

VR 10 years ago

AR is the future, and will be much bigger than VR, but it is also a much harder problem to solve.

I know companies that are very interested in professional VR applications today using the Vive, but Hololens isn't practical yet. I think in a few more revs it will be really great. VR now, AR when it's ready, but AR will definitely be bigger.

Maybe starved is too strong a term. I think we're both trying to make the same point - a new medium can exist, but it doesn't mean that the old media go away. You might just use them less. The idea of a new medium replacing an older medium 1-for-1 doesn't make much sense.

That said, the amount of attention people can pay to all media is essentially finite, and new media decreases the hold of old media. In a very real way the internet is killing print newspapers, by drastically reducing the amount of attention that is paid to them.

Likewise, if you look at printed books, they are much less important than they were 100 years ago, largely due to radio, television, movies, computers, and the internet.

If the displays get a lot higher res, I could see myself using stacks of floating displays for apps instead of my current multimonitor display. Imagine being completely surrounded by digital paper that defies the laws of physics.

I've tried Rec Room and I really like it. It's amazing how much fun it is to play with someone else.

It still seems like early days for multiplayer. There's no way to see other people's facial expressions, and the avatars are pretty basic. There's also no support for having a local multiplayer experience. Hololens is doing some interesting things, allowing multiple headsets to see the same holograms, but their hardware is still super limited. The void is also doing interesting things.

I guess I should have said that I want better multiplayer.

I've heard a lot of good things about the Oculus, especially the touch controllers.

My main experience demoing the dk2 around was that the first thing everyone did was try raising their hands in front of their face, and that motion sickness hit about 30% of people. The Vive fixes both of those problems, and they're first to market.

Still, facebook has deep pockets, and from everything I've heard their headset is better and their controllers are better. I can't wait to give them a try.

The next big thing that I want in VR is multiplayer.

A new medium never really replaces an old medium, it just starves all other media for time. So far VR is great for games, experiencing immersive environments (eg destinations), and some design/creation (eg tiltbrush).

I think it will get better as time goes on, but it is already really compelling. I realize I'm an early adopter, but my enthusiasm is only increasing. WebVR is fascinating, and it's possible to create, for example, a really compelling shopping experience where you could see the actual size of objects before buying.

I think rather than assuming malice, assume either incompetence or different goals.

The saying I've heard is that most people want elevators, but we've been selling them helicopters and blaming them when they crash.

Someone who is largely computer illiterate can download and run apps without any fear of messing things up. There is essentially no malware for iOS. They can always exit the app. They can always delete the app. If the app wants to get the user's location, or email, or documents, or pictures, it has to ask for permission from the user. The app will not mess with things that the user can't figure out - there are easy ways to check (and in some cases limit) space usage, bandwidth usage, and battery usage. Apps are now safe.

This is an amazing achievement!

However, apple has not yet figured out how to safely enable development at the same time. They're getting closer, but they're not there yet. It is obvious that that was not their top goal. There are already lots of general purpose computing devices, and if you want development access to your device, you can get it as a developer.

More information here: https://www.levyjournalonline.com/police-beat.html

Relevant section: In a separate crash on May 7 at 3:40 p.m. on U.S. 27 near the BP Station west of Williston, a 45-year-old Ohio man was killed when he drove under the trailer of an 18-wheel semi. The top of Joshua Brown’s 2015 Tesla Model S vehicle was torn off by the force of the collision. The truck driver, Frank Baressi, 62, Tampa was not injured in the crash. The FHP said the tractor-trailer was traveling west on US 27A in the left turn lane toward 140th Court. Brown’s car was headed east in the outside lane of U.S. 27A. When the truck made a left turn onto NE 140th Court in front of the car, the car’s roof struck the underside of the trailer as it passed under the trailer. The car continued to travel east on U.S. 27A until it left the roadway on the south shoulder and struck a fence. The car smashed through two fences and struck a power pole. The car rotated counter-clockwise while sliding to its final resting place about 100 feet south of the highway. Brown died at the scene. Charges are pending.

Here is a google maps view of the accident location: https://goo.gl/maps/SSKyoxhoaxp