# 7 Years of Progress In Snow Simulation! ❄️ ## Метаданные - **Канал:** Two Minute Papers - **YouTube:** https://www.youtube.com/watch?v=JSNE_PIG1UQ - **Дата:** 05.02.2021 - **Длительность:** 6:00 - **Просмотры:** 246,040 ## Описание ❤️ Check out Lambda here and sign up for their GPU Cloud: https://lambdalabs.com/papers 📝 The paper "An Implicit Compressible SPH Solver for Snow Simulation" is available here: https://cg.informatik.uni-freiburg.de/publications/2020_SIGGRAPH_snow.pdf ❤️ Watch these videos in early access on our Patreon page or join us here on YouTube: - https://www.patreon.com/TwoMinutePapers - https://www.youtube.com/channel/UCbfYPyITQ-7l4upoX8nvctg/join 🙏 We would like to thank our generous Patreon supporters who make Two Minute Papers possible: Aleksandr Mashrabov, Alex Haro, Alex Serban, Alex Paden, Andrew Melnychuk, Angelos Evripiotis, Benji Rabhan, Bruno Mikuš, Bryan Learn, Christian Ahlin, Eric Haddad, Eric Lau, Eric Martel, Gordon Child, Haris Husic, Jace O'Brien, Javier Bustamante, Joshua Goller, Kenneth Davis, Lorin Atzberger, Lukas Biewald, Matthew Allen Fisher, Michael Albrecht, Nikhil Velpanur, Owen Campbell-Moore, Owen Skarpness, Ramsey Elbasheer, Robin Graham, Steef, Taras Bobrovytsky, Thomas Krcmar, Torsten Reil, Tybie Fitzhugh. If you wish to support the series, click here: https://www.patreon.com/TwoMinutePapers Thumbnail background image credit: https://pixabay.com/images/id-2522720/ Károly Zsolnai-Fehér's links: Instagram: https://www.instagram.com/twominutepapers/ Twitter: https://twitter.com/twominutepapers Web: https://cg.tuwien.ac.at/~zsolnai/ #gamedev ## Содержание ### [0:00](https://www.youtube.com/watch?v=JSNE_PIG1UQ) Introduction Dear Fellow Scholars, this is Two Minute Papers with Dr. Károly Zsolnai-Fehér. Let’s talk about snow simulations! Being able to simulate snow on our computers is not new, it’s been possible for a few years now, for instance, this legendary Disney paper from 2013 was capable of performing that. ### [0:20](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=20s) Limitations So why do researchers write new papers on this? Well, because the 2013 paper had its limitations. Let’s talk about them while looking at some really sweet footage from a new paper. Limitation number one for previous works is that their snow simulations were sinfully expensive. Most of them took not seconds, and sometimes not even minutes, but half an hour per frame. Yes, that means all nighter simulations. They were also not as good in fracturing interactions, simulating powder snow and avalanches were also out of reach. ### [0:58](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=58s) Challenges Until now. You see, simulating snow is quite challenging. It clumps up, deforms, breaks, and hardens under compression. And even my favorite, phase change from fluid to snow! These are all really challenging to simulate properly, and in a moment, you will see that this new method is capable of even more beyond that. ### [1:21](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=81s) Friction Let’s start with friction. First, we turn on the snow machine. And then, engage the wipers! That looks wonderful. And now, may I request seeing some tire marks? ### [1:37](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=97s) Boundary Friction There you go! This looks really good, so how about taking a closer look at this phenomenon? Vb here is the boundary friction coefficient and it is a parameter that can be chosen freely by us. So let’s see what that looks like! If we initialize this to a low value, we’ll get very little friction, and if we crank this up, look, things get a great deal more sticky. ### [2:06](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=126s) Compression Fracking The big clump of snow also breaks apart in a spectacular manner, also showcasing compression and fracturing beyond the boundary friction effect we just looked at. Oh my! This is beautiful. ### [2:20](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=140s) Virtual Bunnies Okay, now, this is a computer graphics paper. If you are a seasoned Fellow Scholar, you know that this means…it means that it is time to put some virtual bunnies into the oven. This is a great example for rule number one for watching physics simulations, which is that we discuss the physics part, and not the visuals. So why are these bunnies blue? Well, let’s chuck’em in the oven and find out. Aha! They are color coded for temperature. ### [2:53](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=173s) Temperature Look, they start from -100C, that’s the blue, and we see the colors change as they approach zero degrees celsius. At this point they don’t yet start melting, but they are already falling apart, so it was indeed a good design decision to show the temperatures, because it tells us exactly what is going on here. Without it, we would be expecting melting. Well, can we see that melting in action too? You bet. Now, hold on to your papers, and bring forth the soft-ice-o-mat! This machine can not only create an exquisite dessert for computer graphics researchers, but also showcases the individual contributions of this new technique one by one. Look! There is the melting, yes! Add a little frosting, and there you go. Bon appetit! Now, as we feared, many of these larger-scale simulations require computing the physics for millions of particles. So how long does that take? When we need millions of particles, we typically have to wait a few minutes per frame, but if we have a smaller scene, we can get away with these computations in a few seconds per frame! Goodness, we went from hours per frame to seconds per frame in just one paper. Outstanding work. ### [4:25](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=265s) Memory And also, wait a second…if we are talking millions of particles, I wonder how much memory it takes to keep track of them? Let’s see. Whoa…this is very appealing. I was expecting a few gigabytes, yet it only asks for a fraction of it…a couple hundred megabytes. ### [4:47](https://www.youtube.com/watch?v=JSNE_PIG1UQ&t=287s) Conclusion So, with this hefty value proposition, it is no wonder that this paper has been accepted to the SIGGRAPH conference. This is the olympic gold medal of computer graphics research, if you will. Huge congratulations to the authors of this paper… this was quite an experience. What a time to be alive! Thanks for watching and for your generous support, and I'll see you next time! --- *Источник: https://ekstraktznaniy.ru/video/13984*