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Interstellar movie black hole implemented with Einstein's equations in C++
- usrnm 2y agoI wonder if people who wrote that code also consider their job boring and uninspiring
- gigatexal 2y agodo you? sorry to hear that!
- dvh 2y agoJeez not another stand-up on spaghettification before lunch!
- KaiserPro 2y agoStandup! god I wish. It'd more like a producer going: "is it done yet?" "what do you mean it'll take half our rendering budget, I need that for delivery" "Is it done yet?" "can you make it look more spacey?" "no thats too spacey now" "Why isnt there lens flare?" "Why does it take two weeks to render, can't you fake it?"
- krona 2y agoPerhaps they resented not being able to write it in MATLAB.
- newswasboring 2y agoAre you implying people like writing MATLAB? I've been writing MATLAB for about 10 years now, never once enjoyed it.
- moomin 2y agoThey work in VFX, so their primary concerns are getting enough sleep and being able to pay rent.
- zerr 2y agoRepetitively translating existing formulas to code is not that satisfying.
- mr_mitm 2y agoWriting numerical solvers isn't that inspiring by itself to be honest. But I agree that the subject is fascinating. I suppose the code is not public so we could see ourselves, is it?
- jebarker 2y agoI don't understand the motivation for this comment, can you explain?
- hermitcrab 2y agoIt is a pity they didn't spend comparable effort on the story. I thought it was a really disappointing film, especially after they banged on so much about how good the physics in it was (apart from the black hole rendering, it wasn't).
- guitarlimeo 2y agoDid we watch the same movie? They got bunch of physics stuff right, like the water planet, the relative aging due to being near the massive black hole etc. Only thing that wasn't "correct" was the wormhole and especially the tesseract, but that was some creative writing which allowed for a nice twist. I enjoyed it, a nice scifi.
- kawa 2y agoTheir starship was bullshit. On earth they needed a big Saturn 5 like rocket to bring it into space and later they fly into orbit like it's nothing. If the planets they visited had much lower gravity then earth this may be possible, but this wasn't noticeable or talked about. And even on Mars you need much more fuel to get into orbit than could be stored in their tiny ship.
- deleted 2y ago[deleted]
- AlexGizis 2y agoTo expand on this, if they tried to land on the water planet where time so dilated that one hour equals 7 months… what would their velocity have been when they contacted the surface? And how much energy did their spaceship need to reach escape velocity from there?
- wizzwizz4 2y agoEh, this isn't actually that bad. It's quite easy, using a jet aircraft, to (via a ballistic trajectory) get into space. Surrounded by reaction mass as you are, the rocket equation isn't nearly so bad. You could conceivably dock with something in orbit, if you had elastic tethers or something to make the acceleration survivable. If you're much lighter than what you're docking with, you won't knock the satellite out of orbit. Heck, you could even ignore the jet aspect, and go for full rocket. (An ICBM only weighs around 50 tonnes, after all.) Getting the heavy thing into orbit, though, requires proper, multi-stage rockets.
- bachmeier 2y agoThe title is basically nonsense. They're talking about the black hole in that movie.
- kjrfghslkdjfl 2y agoWhat did you expect from the title? That they used Einstein's equations to render the actors? Of course it's the black hole.
- didgeoridoo 2y agoSince the digital movie camera used to film the actors relies on the photoelectric effect to turn light into pixel data, you could say Einstein’s equations were used for the live-action portion too!
- deep_merge 2y agoUm actually… Chris Nolan doesn’t shoot digital. His more recent pictures (Interstellar included) are shot on a mixture of 35mm, 70mm and IMAX 70mm (!)
- didgeoridoo 2y agoThe light-sensitive chemicals in film also rely on the photoelectric effect! YOU CAN’T ESCAPE EINSTEIN, NOLAN.
- mapimopi 2y agoWhat's the difference between 70mm and IMAX 70mm? Is it just the aspect ratio (2.20:1 vs 1.43:1)?
- deep_merge 2y agoYes, it’s an even larger format than traditional 70mm. The cells are physically larger. Anecdote: Nolan worked with Kodak to invent black & white IMAX film for Oppenheimer. https://www.kodak.com/en/motion/blog-post/oppenheimer/ https://www.kodak.com/en/motion/blog-post/oppenheimer/
- lmpdev 2y agoInterstellar blackhole VFX implemented in 40k lines of C++ Would be a better title
- sigmoid10 2y agoImplemented using semi-realistic Einstein equations. They do talk about implementing a fully realistic version in the paper, but the director deemed it visually too confusing for the audience, so you only get to see a dumbed-down version in the movie.
- fredski42 2y agoIs there a visualization of the fully realistic version available somewhere?
- GuB-42 2y agoYes, there is https://www.researchgate.net/figure/a-The-moderately-realistic-accretion-disk-of-figure-14-but-with-the-black-holes-spin_fig15_272195705 https://www.researchgate.net/figure/a-The-moderately-realist...
- Culonavirus 2y agoThat looks so much more menacing, almost supernatural, a stellar ghost.
- indigoabstract 2y agoIt's clickbait, but I'm amused since it implies the blackhole is the main star of the movie.
- tgv 2y agoIs it not? Would you say the Sun was the main star then?
- NKosmatos 2y agoIf you want to avoid opening Twitter (now known as X), here is the link to the paper: https://arxiv.org/pdf/1502.03808 https://arxiv.org/pdf/1502.03808 TLDR “A typical IMAX image has 23 million pixels, and for Interstellar we had to generate many thousand images, so DNGR had to be very efficient. It has 40,000 lines of C++ code and runs across Double Negative’s Linux-based render-farm. Depending on the degree of gravitational lensing in an image, it typically takes from 30 minutes to several hours running on 10 CPU cores to create a single IMAX image. Our London render-farm comprises 1633 Dell-M620 blade servers; each blade has two 10-core E5-2680 Intel Xeon CPUs with 156GB RAM. During production of Interstellar, several hundred of these were typically being used by our DNGR code.“
- slig 2y agoHow fast could this run in a modern CPU with a modern GPU?
- jsheard 2y agoGPUs are almost irrelevant for VFX work at this scale due to the memory requirements. The render nodes used for Interstellar had 156GB of RAM, and a decade later the biggest GPUs still don't have that much memory (unless you count Macs I suppose but the existing software ecosystem is very CUDA-centric). Small VFX shops do typically render on GPUs nowadays, but the high end is still dominated by CPU rendering.
- pjmlp 2y agoAs a matter of fact, Pixar render farm is mostly based on CPU rendering.
- jsheard 2y agoThat goes for all the biggest players - Pixar, WDAS, Dreamworks, ILM, WETA, Framestore... all do their final rendering on CPUs. Some of them have adopted a hybrid workflow where artists can use GPU rendering to quickly iterate on small slices of data though.
- ginko 2y agoThere was a pretty good talk[1] on this at SIGGRAPH 2015. Speakers included later Nobel prize winner Kip Thorne. I tried to find any recordings but had no luck. (Presumably it's on the conference DVD) [1] https://history.siggraph.org/learning/double-negative-presents-the-visual-effects-of-interstellar-by-thorne-franklin-james-and-tunzelmann/ https://history.siggraph.org/learning/double-negative-presen...
- idk1 2y ago[possible spoiler alert] Is Intersetllar the movie where Matthew McConaughey turned into a bookcase?
- Waterluvian 2y agoIt’s the one where Matt Damon gets stuck on another planet. No not that one. Not that one either.
- fouronnes3 2y agoNew Fermi estimation interview question just dropped: are there more movies where Matt Damon is stuck on a planet, or movies where Tom Hanks plays a captain?
- ecocentrik 2y agoYou could ask Daniel Defoe or the cast of Gilligan's Island.
- ane 2y agoIs the third movie supposed to be Elysium?
- danielbln 2y agoHe didn't turn into a book case, but a book case as a sort of representation of multi dimensional space was a part of the movie, yes.
- cossatot 2y agoAnd the infinite book case is a shout out to Borges, right?
- ropejumper 2y agoNot turned into, he got put into a projection of a higher-dimensional space at the location of his daughter's bookcase some time in the past.
- manuelmoreale 2y agoThere’s an interesting discussion related to this in this video: https://youtube.com/watch?v=Z4oy6mnkyW4 https://youtube.com/watch?v=Z4oy6mnkyW4
- mode80 2y agoScienceClic did an excellent video about the accuracy with a better recreation: https://youtu.be/ABFGKdKKKyg https://youtu.be/ABFGKdKKKyg
- KaiserPro 2y agoI worked on this movie, I was at DNEG at the time. One of the standout things that I remember is that this particular simulation was toxic to the fileserver that it was being stored on. From what I recall, I don't think that it was running on that many machines at once. Mainly because it required the high memory nodes that were expensive. I think it was only running on ~10 possibly 50 machines concurrently. But I could be wrong. What it did have was at least one dedicated fileserver though. Each of the file servers at the time were some dual proc dell 1u thing with as much ram as you could stuff in them at the time (384 gigs I think). They were attached by SAS to a single 60 drive 4u raid array. (Dell PowerVault MD3460 or something along those lines. They are rebadged by Dell and were the first practical hotswap enclosure that took normal 3.5" SAS drives, that didn't cost the earth) The array was formatted into 4 raid6 groups, and LVM'd together on the server. it was then shared out by NFS over bonded 10gig links. Anyway. That simulation totally fucked the disks in the array. By the time it finished (I think it was a 2 week run time) it had eaten something like 14 hard drives. Every time a new disk was inserted, another would start to fail. It was so close to fucking up the whole time. I had thought that the simulation was a plugin for houdini, or one of the other fluid simulation engines we had kicking around, rather than a custom 40k C++ program.
- greggsy 2y agoThe paper mentions that the accretion disc was rendered in Houdini. It also mentions that ‘several hundred’ of their 1633 10-core, 156GB (weird number?) blade servers were used, but didn’t seem to go into details on data storage. Is it possible you were working at the compositing phase, which would have been very heavy on random read and writes, resulting in more wear on the disks?
- KaiserPro 2y ago> you were working at the compositing phase, I was a systems engineer at the time. Compositing is actually really quite ideal linear streaming. You read the images serially and tend to write them back serially. which for spinny hard disks is about as optimal as possible. each frame tends to be between 20-150 megs (resolution, layers, bitdepth). but they are rarely read in a random IO way, you start at frame 1 and go to frame there were 32 primary fileservers at the time, two were spare, and, including the nearlines (which were _n_ lustre machines and each had 4 raid arrays attached by SAS rather than one) we'd normally expected to replace twoish disks a week. They ran particle sims all the time. Water, smoke, explosions are all staples of VFX. It was just something weird about this particular sim. My understanding was that the actual simulation was causing the disks to die, rather than the render. A render can be restarted, a sim, less so. Well, this sim at least.
- tempoponet 2y ago> a 32,000-core render farm at about 20 core-hours per frame ~26 2/3 frames per minute, not bad
- sidcool 2y agoThis movie gives me chills everytime I see it. The attention to detail is immaculate.
- DerekL 2y agoTitle is misspelled, should be “black hole” (two words).
- dang 2y agoO K. Thanks!
- joelwallis 2y agoI could do it with Photoshop, two candles of Red Bull and a 5K USD payment in my account. Jokes apart — this is the best SciFi movie ever! It’ll become one of these movies one’s got to rewatch every 5y or so.
- mike503 2y agoI watch it multiple times a year :)