gridspy

33 ms·

331.
by gridspy 6y ago
Because if you run the simulation at a different frame-rate from the rendering it is a huge amount more work. Suddenly you have to start marshaling data through intermediate data structures and apply interpolation to everything. If you then
332.
by gridspy 6y ago
quadratic is a fancy way of saying "this code is super fast with no data, super slow once you have a decent amount" The problem is that when you double the amount of stuff in the JSON document, you quadruple (or more) the scanning
333.
by gridspy 6y ago
Which is a much healthier reaction than blaming the poor employee that changed that config file.
334.
by gridspy 6y ago
Which of course is how the essay ends. He reveals that it was a note to himself.
335.
by gridspy 6y ago
All true. Also, the only company doing propulsive landings of 10 storey tall rockets is SpaceX. I'm looking forward to seeing the landing structure that is going to catch the booster using the grid fins at the launch site.
336.
by gridspy 6y ago
Both you and I agree that aerospace companies should do large scale vehicle simulations, which they do. In addition SpaceX does complex fluid dynamics simulations to design and test their engines. That's likely part of why they have su
337.
by gridspy 6y ago
737-Max crashed because of the "lets analyse this rather than test it" thinking that you described earlier. That and an overly cosy relationship with the FCC and a culture of silencing cautious engineering voices. It's seemed
338.
by gridspy 6y ago
Yes, they plan to land "tanker" starships directly back on earth after they have transferred their fuel to another vessel. They plan to land passenger ballistic re-entry starships which fly without a booster directly to another ci
339.
by gridspy 6y ago
The failures so far relate to the pressurization of the header tanks and the engine performance on re-light (hard problems). I imagine these will be well solved after 100 flights. The assumption that shifting payload is going to boggle the
340.
by gridspy 6y ago
Given two options 1. People doing analysis and hoping to check everything through engineering rigor and (hopefully) good assumptions 2. Test early and often, learning along the way until many positive tests have proven the system I'd p
341.
by gridspy 6y ago
SpaceX Starship boosters are refueled after they land themselves using a pump. Shuttle solid rocket boosters have their shells fished out of the ocean by a boat. Then they return to the factory to be broken into sections and filled with a s
342.
by gridspy 6y ago
Belly flop - https://youtu.be/vRPrLvVaQq8?t=145 (Yes, to reduce the falling speed. No, it lands vertically). Rapidly reusable - You can land it directly on (or next to) a launch platform, refuel it and launch it again the s
343.
by gridspy 6y ago
Sounds like a great example of how a non-island can successfully control the virus and how when the govt stops trying, the virus comes straight back. Also, I bet that when "the public demanded" it was a loud and public minority wh
344.
by gridspy 6y ago
Indeed. Those engines are currently missing partially because there's no reason to lose more engines than strictly necessary and also because they only need that much thrust when the fuel tanks are completely full. If they decide to li
345.
by gridspy 6y ago
It landed. It just can't fly again. ;)
346.
by gridspy 6y ago
The initial star-hopper ("Water tower") is several stories high and covered with cameras pointed at the launch site. That would be my guess.
347.
by gridspy 6y ago
No orbital upper stage has been rapidly reusable. No existing rocket has tried to perform either the "belly flop" or the "Landing flip manouver" that SpaceX is trying to do. The failures are due to complex issues (fuel t
348.
by gridspy 6y ago
Fortunately the force of gravity is much lower on both these bodies so I imagine the belly flop becomes less important. On earth it's also about spreading the heat of reentry over a larger area. Fortunately on Mars (I believe that) the
349.
by gridspy 6y ago
Nice analysis. I can answer your question by illuminating two major points you missed. 1. The StarShip reaches a terminal velocity (in "the bellyflop") of about 200 km/h downwards and remains at that velocity until the "
350.
by gridspy 6y ago
I can relate. I strongly dislike score tables after levels which imply that my success was not successful enough - that I should now compete with the scores of other people.
351.
by gridspy 6y ago
So you're objecting to the gamification ... of games? What would your ideal "not-game" look like? Are you sure you wouldn't be happy with a game like Factorio which is basically a perfect sandbox (despite having lots of
352.
by gridspy 6y ago
We also don't know the true percentage of infected who actually do recover 100% with no long-term issues.
353.
by gridspy 6y ago
You only need troops on the street in areas where there is so much unrest that neighbors can't keep "bad actors" in check. I imagine this only being in the heart of cities. The lack of traffic leads to a reduction in crime ge
354.
by gridspy 6y ago
I believe the uniform nationwide response, free tests and healthcare and the rapid 80% wage subsidy were a huge part of this. Apart from sectors like tourism, there wasn't anyone who truly felt "screwed over" by arbitrary rul
355.
by gridspy 6y ago
You can't have just one measure. You really need all the measures mentioned in the grandparent comment. Kind of no point having the population get tested now in the US. Without contact tracing and quarantine a positive result arrives t
356.
by gridspy 6y ago
Lorry drivers should only live in one city. Anywhere else, they need to "self isolate" - contact-less reception of food, hand-off of documents etc. On return home, they need to assume they became infected en-route and use PPE suit
357.
by gridspy 6y ago
Finally, there was a solid "all of government" pandemic plan. Although it got tidied up and dressed up a bit for the public, the basic structure was already in place (in 2017) well before Covid-19 occurred. This ensured that the r
358.
by gridspy 6y ago
Strong borders are the price you have to pay for very little restriction inside them when most of the world is busy infecting its populace. But yes, tourism or business trips are now infeasible. Fortunately it turns out that they were never
359.
by gridspy 6y ago
Probably because our (NZ) governments are simpler. The entire New Zealand government is probably more similar to a state legislature than it is to the US govt. The UK could have also succeeded but the government didn't have the will to
360.
by gridspy 6y ago
I concur it was hand-wavy. I'd hope there was some acceptable measure you could get through the courts here in the name of health. Such a barrier is only really essential when different states have different rules. If you could get all

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