10 ms·

Boids

391 points by jonbaer 7y ago

dang 7y ago
Related from 2015: https://news.ycombinator.com/item?id=9298338 https://news.ycombinator.com/item?id=9298338 2011: https://news.ycombinator.com/item?id=2504652 https://news.ycombinator.com/item?id=2504652 2014: https://news.ycombinator.com/item?id=7293350 https://news.ycombinator.com/item?id=7293350 One comment from 2018: https://news.ycombinator.com/item?id=17167077 https://news.ycombinator.com/item?id=17167077 (Links for the curious. Reposts are ok after a year: https://news.ycombinator.com/newsfaq.html https://news.ycombinator.com/newsfaq.html)
jsilence 7y ago
Could that be used to simulate the pandemic?
- wwwhizz 7y ago
  Maybe, but a simulation is only as good as its model. If this model of boids does not have the same properties as the pandemic, the simulation is probably not good enough. For a nice visualization and simulation of a spreading virus and why social distancing is a good idea: https://www.washingtonpost.com/graphics/2020/world/corona-simulator/ https://www.washingtonpost.com/graphics/2020/world/corona-si...
- qubex 7y ago
  No, definitely not: ‘boids’ serve to show how synchronised collective behaviour can arise in swarms of agents that can observe only a handful of their closest neighbours whilst following pre-determined rules. Virii have no such perceptive capability. S-I-R (Susceptible, Infected, Recovered/Removed) models of epidemiology are a far better place to begin for reasonably realistic and tractable modelling and prediction of epidemics.
- jonbaer 7y ago
  I think (maybe) a better question might be if a boids strategy could somehow be used to avoid a pandemic(?) - if all information is known. Seems like we are all performing a 6ft. collision detection @ the moment.
  - DonHopkins 7y ago
    Speaking of boids and social distancing, Craig Reynolds (author of Boids) has also developed the open source library/toolkit "OpenSteer: Steering Behaviors for Autonomous Characters". It's based on his GDC 1999 paper, "Steering Behaviors For Autonomous Characters". I think there's a Unity3D plugin that incorporates a derivative of that code. In OpenSteer terms, social distancing would include "unaligned collision avoidance" and "separation" steering behaviors, which can be combined with other behaviors including "seek", "flee", "pursuit", "evasion", "offset pursuit", "arrival", "obstacle avoidance", "wanderer", "path following", "wall following", "containment", "flow field following", "cohesion", "alignment", and "leader following". You can also implement your own custom plug-ins, if you need something special like "curly floor spinning". https://www.youtube.com/watch?v=T2iZPRif2i4 https://www.youtube.com/watch?v=T2iZPRif2i4 http://www.red3d.com/cwr/steer/ http://www.red3d.com/cwr/steer/ http://www.red3d.com/cwr/papers/1999/gdc99steer.html http://www.red3d.com/cwr/papers/1999/gdc99steer.html http://www.red3d.com/cwr/steer/gdc99/ http://www.red3d.com/cwr/steer/gdc99/ https://forum.unity.com/threads/opensteer-for-unity3d.26906/ https://forum.unity.com/threads/opensteer-for-unity3d.26906/ https://code.google.com/archive/p/opensteerdotnet/ https://code.google.com/archive/p/opensteerdotnet/ https://github.com/ricardojmendez/UnitySteer https://github.com/ricardojmendez/UnitySteer http://opensteer.sourceforge.net/ http://opensteer.sourceforge.net/ OpenSteer is a C++ library to help construct steering behaviors for autonomous characters in games and animation. In addition to the library, OpenSteer provides an OpenGL-based application called OpenSteerDemo which displays predefined demonstrations of steering behaviors. The user can quickly prototype, visualize, annotate and debug new steering behaviors by writing a plug-in for OpenSteerDemo. OpenSteer provides a toolkit of steering behaviors, defined in terms of an abstract mobile agent called a "vehicle." Sample code is provided, including a simple vehicle implementation and examples of combining simple steering behaviors to produce more complex behavior. OpenSteer's classes have been designed to flexibly integrate with existing game engines by either layering or inheritance. OpenSteerDemo's plug-in framework allows a game AI programmer to quickly prototype behaviors during game design, and to develop behaviors before the main game engine is finished. OpenSteerDemo allows the user to interactively adjust aspects of the simulation. The user can: start, stop and single step time, select the vehicle/ character/ agent of interest, adjust the camera's view and its tracking behavior. OpenSteer is distributed as open source software in accordance with the MIT License. OpenSteer was developed with the generous support of Sony Computer Entertainment America. OpenSteer is supported on Linux, Mac OS X and Windows. Last modified: October 25, 2004
- pinkfoot 7y ago
  #3Blue1Brown has decent (simple) SIR epidemic simulation https://youtu.be/gxAaO2rsdIs https://youtu.be/gxAaO2rsdIs
  - timtimmy 7y ago
    It's a great video. His source is here: https://github.com/3b1b/manim/blob/shaders/from_3b1b/active/sir.py https://github.com/3b1b/manim/blob/shaders/from_3b1b/active/...
- vortico 7y ago
  No. It's an unrelated set of rules. The best way to simulate a disease is to model each person in the country as an individual agent. Even a naive movement model for humans won't look like anything like bird flocking.
  - Applejinx 7y ago
    Physical movement. It struck me that movement of belief systems looks LOTS like boid flocking. It's even possible to map social connectedness by things like Facebook etc. to size of neighborhood, and probably limits on how large a 'neighborhood' can practically be when it represents the belief systems of those in contact with you.
- deleted 7y ago
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qubex 7y ago
I recommend one of my favourite books, Gary William Flake’s 1998 The Computational Beauty of Nature to anybody interested in boids or other computational models of social, chemical, and physical phenomena. Therein the author covers boids extensively and in detail. If I am not mistaken it is in section 16.3 that the author treats boids fairly extensively.
- SanderSantema 7y ago
  That's right, currently reading it for my uni course :)
- jonbaer 7y ago
  He just did a great interview @ https://podcasts.apple.com/us/podcast/gary-flake-scientist-author-former-cto-search-at-salesforce/id1480732807?i=1000469330999 https://podcasts.apple.com/us/podcast/gary-flake-scientist-a...
matsemann 7y ago
I have an implementation here [0] if people want to play with it. Supports dynamically changing the controls, has obstacles and predators. Setting weights for separation, alignment and cohesion to zero and then increasing only one of them nicely shows which role each of them plays. It's actually made as a workshop [1] for my company, where the shell is provided and one has to implement it step by step. In Norwegian, though. Update: Dang linked other discussions, and I see I commented on one from 2015 [2]. Someone there asked for the course content, and that's available (in English!) in a PDF in [1]. This workshop/implementation is actually an example of what I wanted the students to make at the time. Which I then retrofitted to a fun workshop for my colleagues. [0]: https://matsemann.github.io/boids-workshop/ https://matsemann.github.io/boids-workshop/ [1]: https://github.com/Matsemann/boids-workshop https://github.com/Matsemann/boids-workshop [2]: https://news.ycombinator.com/item?id=9300142 https://news.ycombinator.com/item?id=9300142
- parhamn 7y ago
  I had fun playing with the parameters, thanks! Now, I want a wallpaper version of this with low maxSpeeds. Very relaxing.
  - w-ll 7y ago
    Remember when Windows allowed you to set a .html file as a desktop background. Wallpaper Engine [0] might be your next best bet. 0. https://store.steampowered.com/app/431960/Wallpaper_Engine/ https://store.steampowered.com/app/431960/Wallpaper_Engine/
- kpgiskpg 7y ago
  That's fun, thanks!
- zanderwohl 7y ago
  These guys behave just like the implementation I wrote! I worked out how to do separation, cohesion, and alignment based on written descriptions as an exercise.
- nitrogen 7y ago
jonbaer 7y ago
Boids in 3D Unity: https://github.com/SebLague/Boids https://github.com/SebLague/Boids and the excellent related video https://www.youtube.com/watch?v=bqtqltqcQhw https://www.youtube.com/watch?v=bqtqltqcQhw
- semi-extrinsic 7y ago
  Blender also has boids you can play with. Here are some fishy ones: https://m.youtube.com/watch?v=zN2bhKyCJwk https://m.youtube.com/watch?v=zN2bhKyCJwk It looks really good even though the "fish" are just made from two pyramids.
- juanuys 7y ago
  Does it use the GPU? https://github.com/SebLague/Boids/blob/master/Assets/Scripts/BoidCompute.compute https://github.com/SebLague/Boids/blob/master/Assets/Scripts... If so, then awesome :)
mehmetoguzderin 7y ago
WGSL [0] implementation of Boids: https://dawn.googlesource.com/tint/+/refs/heads/master/test/compute_boids.wgsl https://dawn.googlesource.com/tint/+/refs/heads/master/test/... [0]: http://gpuweb.github.io/gpuweb/wgsl http://gpuweb.github.io/gpuweb/wgsl
bschne 7y ago
Dan Shiffman over on The Coding Train has a nice walkthrouhg of implementing this in P5.js https://www.youtube.com/watch?v=mhjuuHl6qHM https://www.youtube.com/watch?v=mhjuuHl6qHM
- mar77i 7y ago
  Recently did that code as presented using pygame, but I haven't uploaded it anywhere yet, that might be a good idea, though.
deleted 7y ago
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DonHopkins 7y ago
I've confirmed with Craig Reynolds that yes indeed, then name of Boids was inspired by The Producers: https://www.youtube.com/watch?v=aL6mTMShVyk https://www.youtube.com/watch?v=aL6mTMShVyk >"He's up on the roof with his boids. He keeps boids. Doity, disgusting, filthy, lice ridden boids." -The Concierge, not a Madam
- rootbear 7y ago
  I had no idea! I would have guessed it was a contraction of "bird-oid", or something like that.
  - DonHopkins 7y ago
    That too, but it's only the cover story for people without a New York Metropolitan accent! https://en.wikipedia.org/wiki/Boids https://en.wikipedia.org/wiki/Boids >Boids is an artificial life program, developed by Craig Reynolds in 1986, which simulates the flocking behaviour of birds. His paper on this topic was published in 1987 in the proceedings of the ACM SIGGRAPH conference. The name "boid" corresponds to a shortened version of "bird-oid object", which refers to a bird-like object. Incidentally, "boid" is also a New York Metropolitan dialect pronunciation for "bird".
  - DonHopkins 7y ago
    I asked Craig if he had any good Boids links, and he dug these up! (Plus a few more I found.) https://web.archive.org/web/19990117095925/https://http1.brunel.ac.uk:8080/research/AI/alife/al-boids.htm https://web.archive.org/web/19990117095925/https://http1.bru... >Craig Reynolds' Boids >"The motion of a flock of birds is... simple in concept yet is so visually complex it seems randomly arrayed and yet is magnificently synchronous. Perhaps most puzzling is the strong impression of intentional centralised control. Yet all evidence indicates that flock motion must be merely the aggregate result of the actions of individual animals, each acting solely on the basis of its local perception of the world." - Craig Reynolds [...] >References: "Artificial Life : The Quest for a New Creation" - Steven Levy https://books.google.nl/books/about/Artificial_Life.html?id=hN7CQgAACAAJ&redir_esc=y https://books.google.nl/books/about/Artificial_Life.html?id=... Steve Levy's page on his "Artificial Life" book (with glorious 1997 web site design): https://web.archive.org/web/19981202151154/http://www.echonyc.com/~steven/alife.html https://web.archive.org/web/19981202151154/http://www.echony... Tal Cohen's Bookshelf: Artificial Life: The Quest for a New Creation / Steven Levy http://neuro.bstu.by/ai/To-dom/My_research/failed%201%20subitem/Def-of-life/Langton/Artificial%20Life%20The%20Quest%20for%20a%20New%20Creation%20-%20Steven%20Levy.htm http://neuro.bstu.by/ai/To-dom/My_research/failed%201%20subi... Bruce Sterling. Artificial life. http://lib.ru/STERLINGB/f_sf_04.txt http://lib.ru/STERLINGB/f_sf_04.txt Half Life Wiki: Boid https://half-life.fandom.com/wiki/Boid https://half-life.fandom.com/wiki/Boid >A "Boid" is a virtual entity used in "Boids", an artificial life program simulating the behavior of birds or fish in their flocks or schools, respectively (with each other, as well as their environment), developed at Symbolics Inc. in 1986 by Craig Reynolds, an artificial life and computer graphics expert, and named "steering behavior".[1] The source code has been released a few years after 1986, allowing the creation of many variants since then, including Valve's creature (that even resembles the original Boids by Reynolds). It is also implemented in the free C++ library OpenSteer, designed to help construct steering behaviors for autonomous characters in games and animation. >The term "Boid" is the abbreviation of "birdoid" ("like a bird"), as the program rules applied equally to simulated flocking birds and schooling fish. It was also inspired by a scene from Mel Brooks' 1968 film The Producers where the playwright's landlord complained about his keeping pigeons on the roof, referring to them as "boids", or "bird" in a stereotypical New York accent. The term also linked up with the ellipsoid-based 3D modeling tool by Tom Duff at the Graphics Lab of New York Institute of Technology named "soids".[2] Therefore, in regard of the source of the creature's name, its proper in-universe name remains unknown. Alvy Ray Smith used Tom Duff's "soids" (short for "ellipsoids") for Chromagnon: http://alvyray.com/Art/Chromagnon.htm http://alvyray.com/Art/Chromagnon.htm >I modeled the skeletal hands from cylinders and spheres, using Tom's "soids" program. Roadmap-Based Methods for Flocking Motion with Obstacles https://www.cs.umd.edu/~mount/Indep/Kevin/Webpage/index.htm https://www.cs.umd.edu/~mount/Indep/Kevin/Webpage/index.htm >It was also inspired by a graphics modelling and rendering system by Tom Duff when he was at the Computer Graphics Lab of the New York Institute of Technology. It used ellipsoids as its primitive shape and was called "soids". Craig Reynolds Boids page https://web.archive.org/web/19981202064632/http://www.hmt.com/cwr/boids.html https://web.archive.org/web/19981202064632/http://www.hmt.co... >Boids: Background and Update, by Craig Reynolds. >[You need to be using an Java-enabled browser to see this demo.] (more information about this applet is available) >In 1986 I made a computer model of coordinated animal motion such as bird flocks and fish schools. It was based on three dimensional computational geometry of the sort normally used in computer animation or computer aided design. I called the software boids. [...] Brunel University Artificial Intelligence Site / Artificial Life / Boids / Three "Boid" Term Sources https://web.archive.org/web/20010505042228/http://www.brunel.ac.uk/research/AI/alife/alife-main.html https://web.archive.org/web/20010505042228/http://www.brunel... https://web.archive.org/web/20010224013859fw_/http://www.brunel.ac.uk/research/AI/alife/al-boids.htm https://web.archive.org/web/20010224013859fw_/http://www.bru... https://web.archive.org/web/20001004064622/https://http1.brunel.ac.uk:8080/research/AI/alife/al-boid2.htm https://web.archive.org/web/20001004064622/https://http1.bru... >I have learned (on extremely good authority!) that there were actually three sources of the term 'boid'! Here they are: >"Boid" was an abbreviation of "birdoid", as his rules applied equally to simulated flocking birds, and schooling fish. >It was also inspired by a graphics modelling and rendering system by Tom Duff when he was at the Computer Graphics Lab of the New York Institute of Technology. It used ellipsoids as its primitive shape and was called "soids". >Finally, there was a Mel Brooks film called The Producers starring Zero Mostel and Gene Wilder which contained a scene where the playwright's landlord complained about his keeping pigeons on the roof ("You used to be able to sit on the stoop like a normal person, but not any more, 'cause of da BOIDS. Dirty, lousy, stinkin' BOIDS")
diekhans 7y ago
It is a beautiful paper, well worth reading the original.
deleted 7y ago
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diggan 7y ago
If you're in 3D animation/modeling/whatever and have a little bit of experience, Blender has a pretty stable simulation of Boids that is lots of fun to play around with. It's been built-in into Blender since... For as long as I remember, and it has lots of properties you can play around with, and you can also make the boids be rigid bodies as well so they can interact with other elements in your scene. Some links if you want to try it out: - https://docs.blender.org/manual/en/latest/physics/particles/emitter/physics/boids.html https://docs.blender.org/manual/en/latest/physics/particles/... - https://www.blendernation.com/2019/07/06/how-to-use-boids-in-blender-2-8/ https://www.blendernation.com/2019/07/06/how-to-use-boids-in... - https://www.blendernation.com/2008/01/05/simulating-flocks-herds-and-swarms-using-experimental-blender-boids-particles/ https://www.blendernation.com/2008/01/05/simulating-flocks-h... - http://feeblemind.tuxfamily.org/blog/index.php?post/2007/12/28/106-setting-a-prey-predator-relationship-using-boids-particles http://feeblemind.tuxfamily.org/blog/index.php?post/2007/12/...
- jedimastert 7y ago
  For even more Blender boid related fun, here's Ian Hurbert's ",lazy tutorial" for animating moths. He's fun https://youtu.be/imkSdlbXB_U https://youtu.be/imkSdlbXB_U
jbverschoor 7y ago
I remember boids was one of the example programs with the direct3d sdk back in the ‘90s
juanuys 7y ago
I made a Three.js boids implementation for an interview once. The role was for web dev, but the theme was "come and teach us about something that interests you" :) https://github.com/juanuys/boids https://github.com/juanuys/boids
jonbaer 7y ago
https://github.com/search?q=boids https://github.com/search?q=boids
- banana-slug 7y ago
  Note that this one (https://github.com/meshula/OpenSteer https://github.com/meshula/OpenSteer) is the “semi official” port of OpenSteer, a library for steering behaviors, which is the generalization of the ideas underlying boids, as described in http://www.red3d.com/cwr/papers/1999/gdc99steer.html http://www.red3d.com/cwr/papers/1999/gdc99steer.html
ur-whale 7y ago
Slightly OT, but this is a very interesting problem to implement on a GPU because it very much resembles in its structure the implementation of exact N-body simulator on massively parallel machines.
- glouwbug 7y ago
  Yes boids are great for parallelization. Each boid must compute a stressor imposed by neighboring boids based on the three rules in the paper (separation, alignment, and drifting towards center of mass). The stressor for each boid is simply applied to each boids velocity. Given a thousand threads / cpus / cuda cores, what have you, each unit can be applied to a single boid
glouwbug 7y ago
StarCraft 2 used boids, and I'm using boids to rewrite Age of Empires II: github.com/glouw/openempires
- marktangotango 7y ago
  I’ve often pondered the feasibility of using boids (or a boid like rule system) to implement ancient combat formations like pike squares skirmish lines. Is that what you’re doing?
  - pugworthy 7y ago
    Here's an answer I put up on gamedev stackexchange a while back with that idea in mind -> https://gamedev.stackexchange.com/questions/166448/rts-attack-formation/167375#167375 https://gamedev.stackexchange.com/questions/166448/rts-attac...
  - glouwbug 7y ago
    Yes, though I'm not at the formation stage just yet. Boids just know how to stear organically much like Zerglings do. Boids just provide distancing at the micro level. Astar or Greedy First Best at the macro level ultimately provides the boid with a final destination, and the boids organically work together on path to their respective final destinations. Rise of Nations did it almost perfectly in the early 2000s with left box drag for selection and right box drag for retangular placement. Rome Total War upped the antics a bit with 10,000 unit scales over Rise of Nations 200 unit scales, but suffered some serious bugs. In my opinion no one except Julius Caesar can "program" so many units to properly do their bidding!
anotheryou 7y ago
Beautiful example: https://twitter.com/OskSta/status/1219340987299966976 https://twitter.com/OskSta/status/1219340987299966976 https://twitter.com/OskSta/status/1219343599336333319 https://twitter.com/OskSta/status/1219343599336333319 https://twitter.com/OskSta/status/1225037781858234368 https://twitter.com/OskSta/status/1225037781858234368
- mshafer 7y ago
  Oskar’s tweets showing his city-builder are some of my favourite things on the internet. His combination of 3D rendering and artistic style is just black magic to me.
  - anotheryou 7y ago
    A real challenger to the Return of the Obra Din Devlog :) https://forums.tigsource.com/index.php?PHPSESSID=qvfvkcqtfr9q3kb2rtlqj3j3c1&topic=40832.20 https://forums.tigsource.com/index.php?PHPSESSID=qvfvkcqtfr9...
jaltekruse 7y ago
Might be a dumb thing to post on hacker news, but I tried using the word boid or boids in Scrabble and my competitive wife wouldn't let me because it wasn't in the dictionary. It fit so well too!
- banana-slug 7y ago
  You need a better dictionary: https://www.merriam-webster.com/dictionary/boid https://www.merriam-webster.com/dictionary/boid Long before the flocking model, “boid” referred to snakes of the Boidae family, like boas and anacondas.
  - fanf2 7y ago
    Scrabble doesn't use any dictionary: https://scrabble.merriam.com/finder/boid https://scrabble.merriam.com/finder/boid (for the USA and Canada) https://www.collinsdictionary.com/scrabble/ https://www.collinsdictionary.com/scrabble/ (for English in the rest of the world)
  - contingencies 7y ago
    Previously we played with the Australian reference, the Macquarie Dictionary. Subsequently, as an international family finding that an expensive and static resource insufficiently engaged with international usage we began to play admitting anything in either dictionary.com or wiktionary with an English entry, excepting proper names and non-naturalized acronyms. As official scrabble cheat words cover a lot of random Scots/Welsh, you might choose to permit those (single result page on Wiktionary). It starts to get ridiculous fast. I personally love the learning aspect and we do not play the traditional "challenge" rule, in fact we actively encourage consultation of reference works before and after each play. I am a big fan of Wiktionary, occasionally adding to existing English and Middle Chinese entries. For example, according to Wiktionary, boid (and its plural) should be permitted under etymology two, ie. member of the family Boidae of non-venomous snakes or etymology three, ie. Nonstandard spelling of bird representing the New York City pronunciation. We would not permit it under etymology one (computer program name). Now look - you learned something! https://en.wiktionary.org/wiki/boid#English https://en.wiktionary.org/wiki/boid#English
jzting 7y ago
I also have an implementation [0] that shows the paths of the boids. Based on the parameters, some very interesting patterns emerge! [0] http://jzlabs.com/ http://jzlabs.com/
gdubs 7y ago
I recently implemented boids in a compute shader [1]. It’s using Apple’s Metal framework, and rendered in 3D. The boids are simple triangles, and I added a bit of specular shading to give them a little bit of a “shimmer” as they flock. I implemented an NVIDIA algorithm for running n-body simulations on the GPU. The constraint is memory access, which can freeze up in a case like this. [2]. Converting from CUDA to Metal wasn’t too bad. 1: https://www.instagram.com/p/B4t4ewCplfR/?igshid=1uxnng6idsqb8 https://www.instagram.com/p/B4t4ewCplfR/?igshid=1uxnng6idsqb... 2: https://developer.nvidia.com/gpugems/gpugems3/part-v-physics-simulation/chapter-31-fast-n-body-simulation-cuda https://developer.nvidia.com/gpugems/gpugems3/part-v-physics... edit: Here's a low-res animated GIF for anyone who doesn't want to click an instagram link: http://gregorywieber.com/assets/images/art/murmuration.gif http://gregorywieber.com/assets/images/art/murmuration.gif
- afro88 7y ago
  Love it, and the others on your instagram. You should start a dedicated account for them. I would like to follow your art, but feels weird seeing family photos of someone I don't know :/
miniatureape 7y ago
I posted this simple boid drawing toy a year or two ago: https://miniatureape.github.io/boiddraw/ https://miniatureape.github.io/boiddraw/
foreigner 7y ago
Good old Boids! I implemented a clone of Boids in C as my senior project in high school. It included 3D wireframe graphics from scratch. My teacher said it was "A nice screensaver".
escot 7y ago
> Incidentally, "boid" is also a New York Metropolitan dialect pronunciation for "bird".
banana-slug 7y ago
Nice boid-related tutorial: https://www.youtube.com/watch?v=bqtqltqcQhw https://www.youtube.com/watch?v=bqtqltqcQhw
timtimmy 7y ago
Boids are my favourite hello world for 3D simulation environments. For the last few weeks, I've been using boids to update my GPU programming skills and knowledge of related algorithms in Unity and Unreal. Yesterday I got 0.5 million boids simulating in Unreal Engine at 45 fps on a GTX 1080 [0]. The bottle neck is rendering so many instanced cone meshes, the simulation without rendering can do 1 million boids at 120 fps. I'm borrowing a common data structure used in GPU fluid simulations, the dynamic hashed grid, to calculate the neighbourhood of each boid (cool tutorial here with full source code [1]). We need the neighbourhoods to calculate their urges. My code is a mess at the moment, but if there is interest I can post it to GitHub (Unity and Unreal). Boids are an example of agent-based modelling and swarm systems. I used agent-based modelling in my PhD thesis to construct and simulate realtime, interactive 3D biomolecular models of mitochondria and neuromuscular synapses [2,3]. Now that I'm free (graduated), I'm building an iPad app to teach and communicate structural and molecular biology with immersive, and realtime simulations. Our vision is to make molecular and structural biology immersive and fun. It's not a textbook, it's a little more like Neil Stephenson's young lady's illustrated primer! :D [0]: https://twitter.com/timd_ca/status/1243941167005192192?s=20 https://twitter.com/timd_ca/status/1243941167005192192?s=20 [1]: https://wickedengine.net/2018/05/21/scalabe-gpu-fluid-simulation/ https://wickedengine.net/2018/05/21/scalabe-gpu-fluid-simula... [2]: https://prism.ucalgary.ca/handle/1880/111493 https://prism.ucalgary.ca/handle/1880/111493 [3]: https://youtu.be/6CsxADBpal0 https://youtu.be/6CsxADBpal0
- banana-slug 7y ago
  Here is a thematically-related boids simulation from 2006: https://www.red3d.com/cwr/papers/2006/PSCrowdSandbox2006.pdf https://www.red3d.com/cwr/papers/2006/PSCrowdSandbox2006.pdf Did 10,000 to 20,000 agents at 60 fps. Puny compared to yours, but not bad for 14 years ago! https://www.youtube.com/watch?v=Jpy5rJSVLj8 https://www.youtube.com/watch?v=Jpy5rJSVLj8 https://www.youtube.com/watch?v=ZZoy-8xK0YI https://www.youtube.com/watch?v=ZZoy-8xK0YI
  - timtimmy 7y ago
    Wow. There are some great ideas in that paper.
robotresearcher 7y ago
Reynolds put up a page about Boids in 1995 and added links to related work for a few years. Great stuff. https://www.red3d.com/cwr/boids/ https://www.red3d.com/cwr/boids/
anoopelias 7y ago
Now who doesn't have an implementation of Boids of their own... :) https://anoopelias.github.io/boids/ https://anoopelias.github.io/boids/
- postnihilism 7y ago
  It's a classic :) I made a little framework for building these types of models: https://github.com/jrhdoty/SwarmJS https://github.com/jrhdoty/SwarmJS Here's a boids implementation using it: http://jrhdoty.github.io/SwarmJS/ http://jrhdoty.github.io/SwarmJS/
simonswain 7y ago
I did a browser based Boids version that simulated galactic colonization: https://coldwar.io/deepspace https://coldwar.io/deepspace and a simpler variant with predators: https://coldwar.io/predators https://coldwar.io/predators
dimovich 7y ago
My simple implementation in C / ClojureScript. https://dimovich.github.io/art/ https://dimovich.github.io/art/

391 points by jonbaer 7y ago

dang 7y ago

Related from 2015: https://news.ycombinator.com/item?id=9298338 https://news.ycombinator.com/item?id=9298338 2011: https://news.ycombinator.com/item?id=2504652 https://news.ycombinator.com/item?id=2504652 2014: https://news.ycombinator.com/item?id=7293350 https://news.ycombinator.com/item?id=7293350 One comment from 2018: https://news.ycombinator.com/item?id=17167077 https://news.ycombinator.com/item?id=17167077 (Links for the curious. Reposts are ok after a year: https://news.ycombinator.com/newsfaq.html https://news.ycombinator.com/newsfaq.html)

jsilence 7y ago

Could that be used to simulate the pandemic?

wwwhizz 7y ago
Maybe, but a simulation is only as good as its model. If this model of boids does not have the same properties as the pandemic, the simulation is probably not good enough. For a nice visualization and simulation of a spreading virus and why social distancing is a good idea: https://www.washingtonpost.com/graphics/2020/world/corona-simulator/ https://www.washingtonpost.com/graphics/2020/world/corona-si...
qubex 7y ago
No, definitely not: ‘boids’ serve to show how synchronised collective behaviour can arise in swarms of agents that can observe only a handful of their closest neighbours whilst following pre-determined rules. Virii have no such perceptive capability. S-I-R (Susceptible, Infected, Recovered/Removed) models of epidemiology are a far better place to begin for reasonably realistic and tractable modelling and prediction of epidemics.
jonbaer 7y ago
I think (maybe) a better question might be if a boids strategy could somehow be used to avoid a pandemic(?) - if all information is known. Seems like we are all performing a 6ft. collision detection @ the moment.
- DonHopkins 7y ago
  Speaking of boids and social distancing, Craig Reynolds (author of Boids) has also developed the open source library/toolkit "OpenSteer: Steering Behaviors for Autonomous Characters". It's based on his GDC 1999 paper, "Steering Behaviors For Autonomous Characters". I think there's a Unity3D plugin that incorporates a derivative of that code. In OpenSteer terms, social distancing would include "unaligned collision avoidance" and "separation" steering behaviors, which can be combined with other behaviors including "seek", "flee", "pursuit", "evasion", "offset pursuit", "arrival", "obstacle avoidance", "wanderer", "path following", "wall following", "containment", "flow field following", "cohesion", "alignment", and "leader following". You can also implement your own custom plug-ins, if you need something special like "curly floor spinning". https://www.youtube.com/watch?v=T2iZPRif2i4 https://www.youtube.com/watch?v=T2iZPRif2i4 http://www.red3d.com/cwr/steer/ http://www.red3d.com/cwr/steer/ http://www.red3d.com/cwr/papers/1999/gdc99steer.html http://www.red3d.com/cwr/papers/1999/gdc99steer.html http://www.red3d.com/cwr/steer/gdc99/ http://www.red3d.com/cwr/steer/gdc99/ https://forum.unity.com/threads/opensteer-for-unity3d.26906/ https://forum.unity.com/threads/opensteer-for-unity3d.26906/ https://code.google.com/archive/p/opensteerdotnet/ https://code.google.com/archive/p/opensteerdotnet/ https://github.com/ricardojmendez/UnitySteer https://github.com/ricardojmendez/UnitySteer http://opensteer.sourceforge.net/ http://opensteer.sourceforge.net/ OpenSteer is a C++ library to help construct steering behaviors for autonomous characters in games and animation. In addition to the library, OpenSteer provides an OpenGL-based application called OpenSteerDemo which displays predefined demonstrations of steering behaviors. The user can quickly prototype, visualize, annotate and debug new steering behaviors by writing a plug-in for OpenSteerDemo. OpenSteer provides a toolkit of steering behaviors, defined in terms of an abstract mobile agent called a "vehicle." Sample code is provided, including a simple vehicle implementation and examples of combining simple steering behaviors to produce more complex behavior. OpenSteer's classes have been designed to flexibly integrate with existing game engines by either layering or inheritance. OpenSteerDemo's plug-in framework allows a game AI programmer to quickly prototype behaviors during game design, and to develop behaviors before the main game engine is finished. OpenSteerDemo allows the user to interactively adjust aspects of the simulation. The user can: start, stop and single step time, select the vehicle/ character/ agent of interest, adjust the camera's view and its tracking behavior. OpenSteer is distributed as open source software in accordance with the MIT License. OpenSteer was developed with the generous support of Sony Computer Entertainment America. OpenSteer is supported on Linux, Mac OS X and Windows. Last modified: October 25, 2004
pinkfoot 7y ago
#3Blue1Brown has decent (simple) SIR epidemic simulation https://youtu.be/gxAaO2rsdIs https://youtu.be/gxAaO2rsdIs
- timtimmy 7y ago
  It's a great video. His source is here: https://github.com/3b1b/manim/blob/shaders/from_3b1b/active/sir.py https://github.com/3b1b/manim/blob/shaders/from_3b1b/active/...
vortico 7y ago
No. It's an unrelated set of rules. The best way to simulate a disease is to model each person in the country as an individual agent. Even a naive movement model for humans won't look like anything like bird flocking.
- Applejinx 7y ago
  Physical movement. It struck me that movement of belief systems looks LOTS like boid flocking. It's even possible to map social connectedness by things like Facebook etc. to size of neighborhood, and probably limits on how large a 'neighborhood' can practically be when it represents the belief systems of those in contact with you.
deleted 7y ago
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qubex 7y ago

I recommend one of my favourite books, Gary William Flake’s 1998 The Computational Beauty of Nature to anybody interested in boids or other computational models of social, chemical, and physical phenomena. Therein the author covers boids extensively and in detail. If I am not mistaken it is in section 16.3 that the author treats boids fairly extensively.

SanderSantema 7y ago
That's right, currently reading it for my uni course :)
jonbaer 7y ago
He just did a great interview @ https://podcasts.apple.com/us/podcast/gary-flake-scientist-author-former-cto-search-at-salesforce/id1480732807?i=1000469330999 https://podcasts.apple.com/us/podcast/gary-flake-scientist-a...

matsemann 7y ago

I have an implementation here [0] if people want to play with it. Supports dynamically changing the controls, has obstacles and predators. Setting weights for separation, alignment and cohesion to zero and then increasing only one of them nicely shows which role each of them plays. It's actually made as a workshop [1] for my company, where the shell is provided and one has to implement it step by step. In Norwegian, though. Update: Dang linked other discussions, and I see I commented on one from 2015 [2]. Someone there asked for the course content, and that's available (in English!) in a PDF in [1]. This workshop/implementation is actually an example of what I wanted the students to make at the time. Which I then retrofitted to a fun workshop for my colleagues. [0]: https://matsemann.github.io/boids-workshop/ https://matsemann.github.io/boids-workshop/ [1]: https://github.com/Matsemann/boids-workshop https://github.com/Matsemann/boids-workshop [2]: https://news.ycombinator.com/item?id=9300142 https://news.ycombinator.com/item?id=9300142

parhamn 7y ago
I had fun playing with the parameters, thanks! Now, I want a wallpaper version of this with low maxSpeeds. Very relaxing.
- w-ll 7y ago
  Remember when Windows allowed you to set a .html file as a desktop background. Wallpaper Engine [0] might be your next best bet. 0. https://store.steampowered.com/app/431960/Wallpaper_Engine/ https://store.steampowered.com/app/431960/Wallpaper_Engine/
kpgiskpg 7y ago
That's fun, thanks!
zanderwohl 7y ago
These guys behave just like the implementation I wrote! I worked out how to do separation, cohesion, and alignment based on written descriptions as an exercise.
nitrogen 7y ago

jonbaer 7y ago

Boids in 3D Unity: https://github.com/SebLague/Boids https://github.com/SebLague/Boids and the excellent related video https://www.youtube.com/watch?v=bqtqltqcQhw https://www.youtube.com/watch?v=bqtqltqcQhw

semi-extrinsic 7y ago
Blender also has boids you can play with. Here are some fishy ones: https://m.youtube.com/watch?v=zN2bhKyCJwk https://m.youtube.com/watch?v=zN2bhKyCJwk It looks really good even though the "fish" are just made from two pyramids.
juanuys 7y ago
Does it use the GPU? https://github.com/SebLague/Boids/blob/master/Assets/Scripts/BoidCompute.compute https://github.com/SebLague/Boids/blob/master/Assets/Scripts... If so, then awesome :)

mehmetoguzderin 7y ago

WGSL [0] implementation of Boids: https://dawn.googlesource.com/tint/+/refs/heads/master/test/compute_boids.wgsl https://dawn.googlesource.com/tint/+/refs/heads/master/test/... [0]: http://gpuweb.github.io/gpuweb/wgsl http://gpuweb.github.io/gpuweb/wgsl

bschne 7y ago

Dan Shiffman over on The Coding Train has a nice walkthrouhg of implementing this in P5.js https://www.youtube.com/watch?v=mhjuuHl6qHM https://www.youtube.com/watch?v=mhjuuHl6qHM

mar77i 7y ago
Recently did that code as presented using pygame, but I haven't uploaded it anywhere yet, that might be a good idea, though.

deleted 7y ago

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DonHopkins 7y ago

I've confirmed with Craig Reynolds that yes indeed, then name of Boids was inspired by The Producers: https://www.youtube.com/watch?v=aL6mTMShVyk https://www.youtube.com/watch?v=aL6mTMShVyk >"He's up on the roof with his boids. He keeps boids. Doity, disgusting, filthy, lice ridden boids." -The Concierge, not a Madam

rootbear 7y ago
I had no idea! I would have guessed it was a contraction of "bird-oid", or something like that.
- DonHopkins 7y ago
  That too, but it's only the cover story for people without a New York Metropolitan accent! https://en.wikipedia.org/wiki/Boids https://en.wikipedia.org/wiki/Boids >Boids is an artificial life program, developed by Craig Reynolds in 1986, which simulates the flocking behaviour of birds. His paper on this topic was published in 1987 in the proceedings of the ACM SIGGRAPH conference. The name "boid" corresponds to a shortened version of "bird-oid object", which refers to a bird-like object. Incidentally, "boid" is also a New York Metropolitan dialect pronunciation for "bird".
- DonHopkins 7y ago
  I asked Craig if he had any good Boids links, and he dug these up! (Plus a few more I found.) https://web.archive.org/web/19990117095925/https://http1.brunel.ac.uk:8080/research/AI/alife/al-boids.htm https://web.archive.org/web/19990117095925/https://http1.bru... >Craig Reynolds' Boids >"The motion of a flock of birds is... simple in concept yet is so visually complex it seems randomly arrayed and yet is magnificently synchronous. Perhaps most puzzling is the strong impression of intentional centralised control. Yet all evidence indicates that flock motion must be merely the aggregate result of the actions of individual animals, each acting solely on the basis of its local perception of the world." - Craig Reynolds [...] >References: "Artificial Life : The Quest for a New Creation" - Steven Levy https://books.google.nl/books/about/Artificial_Life.html?id=hN7CQgAACAAJ&redir_esc=y https://books.google.nl/books/about/Artificial_Life.html?id=... Steve Levy's page on his "Artificial Life" book (with glorious 1997 web site design): https://web.archive.org/web/19981202151154/http://www.echonyc.com/~steven/alife.html https://web.archive.org/web/19981202151154/http://www.echony... Tal Cohen's Bookshelf: Artificial Life: The Quest for a New Creation / Steven Levy http://neuro.bstu.by/ai/To-dom/My_research/failed%201%20subitem/Def-of-life/Langton/Artificial%20Life%20The%20Quest%20for%20a%20New%20Creation%20-%20Steven%20Levy.htm http://neuro.bstu.by/ai/To-dom/My_research/failed%201%20subi... Bruce Sterling. Artificial life. http://lib.ru/STERLINGB/f_sf_04.txt http://lib.ru/STERLINGB/f_sf_04.txt Half Life Wiki: Boid https://half-life.fandom.com/wiki/Boid https://half-life.fandom.com/wiki/Boid >A "Boid" is a virtual entity used in "Boids", an artificial life program simulating the behavior of birds or fish in their flocks or schools, respectively (with each other, as well as their environment), developed at Symbolics Inc. in 1986 by Craig Reynolds, an artificial life and computer graphics expert, and named "steering behavior".[1] The source code has been released a few years after 1986, allowing the creation of many variants since then, including Valve's creature (that even resembles the original Boids by Reynolds). It is also implemented in the free C++ library OpenSteer, designed to help construct steering behaviors for autonomous characters in games and animation. >The term "Boid" is the abbreviation of "birdoid" ("like a bird"), as the program rules applied equally to simulated flocking birds and schooling fish. It was also inspired by a scene from Mel Brooks' 1968 film The Producers where the playwright's landlord complained about his keeping pigeons on the roof, referring to them as "boids", or "bird" in a stereotypical New York accent. The term also linked up with the ellipsoid-based 3D modeling tool by Tom Duff at the Graphics Lab of New York Institute of Technology named "soids".[2] Therefore, in regard of the source of the creature's name, its proper in-universe name remains unknown. Alvy Ray Smith used Tom Duff's "soids" (short for "ellipsoids") for Chromagnon: http://alvyray.com/Art/Chromagnon.htm http://alvyray.com/Art/Chromagnon.htm >I modeled the skeletal hands from cylinders and spheres, using Tom's "soids" program. Roadmap-Based Methods for Flocking Motion with Obstacles https://www.cs.umd.edu/~mount/Indep/Kevin/Webpage/index.htm https://www.cs.umd.edu/~mount/Indep/Kevin/Webpage/index.htm >It was also inspired by a graphics modelling and rendering system by Tom Duff when he was at the Computer Graphics Lab of the New York Institute of Technology. It used ellipsoids as its primitive shape and was called "soids". Craig Reynolds Boids page https://web.archive.org/web/19981202064632/http://www.hmt.com/cwr/boids.html https://web.archive.org/web/19981202064632/http://www.hmt.co... >Boids: Background and Update, by Craig Reynolds. >[You need to be using an Java-enabled browser to see this demo.] (more information about this applet is available) >In 1986 I made a computer model of coordinated animal motion such as bird flocks and fish schools. It was based on three dimensional computational geometry of the sort normally used in computer animation or computer aided design. I called the software boids. [...] Brunel University Artificial Intelligence Site / Artificial Life / Boids / Three "Boid" Term Sources https://web.archive.org/web/20010505042228/http://www.brunel.ac.uk/research/AI/alife/alife-main.html https://web.archive.org/web/20010505042228/http://www.brunel... https://web.archive.org/web/20010224013859fw_/http://www.brunel.ac.uk/research/AI/alife/al-boids.htm https://web.archive.org/web/20010224013859fw_/http://www.bru... https://web.archive.org/web/20001004064622/https://http1.brunel.ac.uk:8080/research/AI/alife/al-boid2.htm https://web.archive.org/web/20001004064622/https://http1.bru... >I have learned (on extremely good authority!) that there were actually three sources of the term 'boid'! Here they are: >"Boid" was an abbreviation of "birdoid", as his rules applied equally to simulated flocking birds, and schooling fish. >It was also inspired by a graphics modelling and rendering system by Tom Duff when he was at the Computer Graphics Lab of the New York Institute of Technology. It used ellipsoids as its primitive shape and was called "soids". >Finally, there was a Mel Brooks film called The Producers starring Zero Mostel and Gene Wilder which contained a scene where the playwright's landlord complained about his keeping pigeons on the roof ("You used to be able to sit on the stoop like a normal person, but not any more, 'cause of da BOIDS. Dirty, lousy, stinkin' BOIDS")

diekhans 7y ago

It is a beautiful paper, well worth reading the original.

deleted 7y ago

[deleted]

diggan 7y ago

If you're in 3D animation/modeling/whatever and have a little bit of experience, Blender has a pretty stable simulation of Boids that is lots of fun to play around with. It's been built-in into Blender since... For as long as I remember, and it has lots of properties you can play around with, and you can also make the boids be rigid bodies as well so they can interact with other elements in your scene. Some links if you want to try it out: - https://docs.blender.org/manual/en/latest/physics/particles/emitter/physics/boids.html https://docs.blender.org/manual/en/latest/physics/particles/... - https://www.blendernation.com/2019/07/06/how-to-use-boids-in-blender-2-8/ https://www.blendernation.com/2019/07/06/how-to-use-boids-in... - https://www.blendernation.com/2008/01/05/simulating-flocks-herds-and-swarms-using-experimental-blender-boids-particles/ https://www.blendernation.com/2008/01/05/simulating-flocks-h... - http://feeblemind.tuxfamily.org/blog/index.php?post/2007/12/28/106-setting-a-prey-predator-relationship-using-boids-particles http://feeblemind.tuxfamily.org/blog/index.php?post/2007/12/...

jedimastert 7y ago
For even more Blender boid related fun, here's Ian Hurbert's ",lazy tutorial" for animating moths. He's fun https://youtu.be/imkSdlbXB_U https://youtu.be/imkSdlbXB_U

jbverschoor 7y ago

I remember boids was one of the example programs with the direct3d sdk back in the ‘90s

juanuys 7y ago

I made a Three.js boids implementation for an interview once. The role was for web dev, but the theme was "come and teach us about something that interests you" :) https://github.com/juanuys/boids https://github.com/juanuys/boids

jonbaer 7y ago

https://github.com/search?q=boids https://github.com/search?q=boids

banana-slug 7y ago
Note that this one (https://github.com/meshula/OpenSteer https://github.com/meshula/OpenSteer) is the “semi official” port of OpenSteer, a library for steering behaviors, which is the generalization of the ideas underlying boids, as described in http://www.red3d.com/cwr/papers/1999/gdc99steer.html http://www.red3d.com/cwr/papers/1999/gdc99steer.html

ur-whale 7y ago

Slightly OT, but this is a very interesting problem to implement on a GPU because it very much resembles in its structure the implementation of exact N-body simulator on massively parallel machines.

glouwbug 7y ago
Yes boids are great for parallelization. Each boid must compute a stressor imposed by neighboring boids based on the three rules in the paper (separation, alignment, and drifting towards center of mass). The stressor for each boid is simply applied to each boids velocity. Given a thousand threads / cpus / cuda cores, what have you, each unit can be applied to a single boid

glouwbug 7y ago

StarCraft 2 used boids, and I'm using boids to rewrite Age of Empires II: github.com/glouw/openempires

marktangotango 7y ago
I’ve often pondered the feasibility of using boids (or a boid like rule system) to implement ancient combat formations like pike squares skirmish lines. Is that what you’re doing?
- pugworthy 7y ago
  Here's an answer I put up on gamedev stackexchange a while back with that idea in mind -> https://gamedev.stackexchange.com/questions/166448/rts-attack-formation/167375#167375 https://gamedev.stackexchange.com/questions/166448/rts-attac...
- glouwbug 7y ago
  Yes, though I'm not at the formation stage just yet. Boids just know how to stear organically much like Zerglings do. Boids just provide distancing at the micro level. Astar or Greedy First Best at the macro level ultimately provides the boid with a final destination, and the boids organically work together on path to their respective final destinations. Rise of Nations did it almost perfectly in the early 2000s with left box drag for selection and right box drag for retangular placement. Rome Total War upped the antics a bit with 10,000 unit scales over Rise of Nations 200 unit scales, but suffered some serious bugs. In my opinion no one except Julius Caesar can "program" so many units to properly do their bidding!

anotheryou 7y ago

Beautiful example: https://twitter.com/OskSta/status/1219340987299966976 https://twitter.com/OskSta/status/1219340987299966976 https://twitter.com/OskSta/status/1219343599336333319 https://twitter.com/OskSta/status/1219343599336333319 https://twitter.com/OskSta/status/1225037781858234368 https://twitter.com/OskSta/status/1225037781858234368

mshafer 7y ago
Oskar’s tweets showing his city-builder are some of my favourite things on the internet. His combination of 3D rendering and artistic style is just black magic to me.
- anotheryou 7y ago
  A real challenger to the Return of the Obra Din Devlog :) https://forums.tigsource.com/index.php?PHPSESSID=qvfvkcqtfr9q3kb2rtlqj3j3c1&topic=40832.20 https://forums.tigsource.com/index.php?PHPSESSID=qvfvkcqtfr9...

jaltekruse 7y ago

Might be a dumb thing to post on hacker news, but I tried using the word boid or boids in Scrabble and my competitive wife wouldn't let me because it wasn't in the dictionary. It fit so well too!

banana-slug 7y ago
You need a better dictionary: https://www.merriam-webster.com/dictionary/boid https://www.merriam-webster.com/dictionary/boid Long before the flocking model, “boid” referred to snakes of the Boidae family, like boas and anacondas.
- fanf2 7y ago
  Scrabble doesn't use any dictionary: https://scrabble.merriam.com/finder/boid https://scrabble.merriam.com/finder/boid (for the USA and Canada) https://www.collinsdictionary.com/scrabble/ https://www.collinsdictionary.com/scrabble/ (for English in the rest of the world)
- contingencies 7y ago
  Previously we played with the Australian reference, the Macquarie Dictionary. Subsequently, as an international family finding that an expensive and static resource insufficiently engaged with international usage we began to play admitting anything in either dictionary.com or wiktionary with an English entry, excepting proper names and non-naturalized acronyms. As official scrabble cheat words cover a lot of random Scots/Welsh, you might choose to permit those (single result page on Wiktionary). It starts to get ridiculous fast. I personally love the learning aspect and we do not play the traditional "challenge" rule, in fact we actively encourage consultation of reference works before and after each play. I am a big fan of Wiktionary, occasionally adding to existing English and Middle Chinese entries. For example, according to Wiktionary, boid (and its plural) should be permitted under etymology two, ie. member of the family Boidae of non-venomous snakes or etymology three, ie. Nonstandard spelling of bird representing the New York City pronunciation. We would not permit it under etymology one (computer program name). Now look - you learned something! https://en.wiktionary.org/wiki/boid#English https://en.wiktionary.org/wiki/boid#English

jzting 7y ago

I also have an implementation [0] that shows the paths of the boids. Based on the parameters, some very interesting patterns emerge! [0] http://jzlabs.com/ http://jzlabs.com/

gdubs 7y ago

I recently implemented boids in a compute shader [1]. It’s using Apple’s Metal framework, and rendered in 3D. The boids are simple triangles, and I added a bit of specular shading to give them a little bit of a “shimmer” as they flock. I implemented an NVIDIA algorithm for running n-body simulations on the GPU. The constraint is memory access, which can freeze up in a case like this. [2]. Converting from CUDA to Metal wasn’t too bad. 1: https://www.instagram.com/p/B4t4ewCplfR/?igshid=1uxnng6idsqb8 https://www.instagram.com/p/B4t4ewCplfR/?igshid=1uxnng6idsqb... 2: https://developer.nvidia.com/gpugems/gpugems3/part-v-physics-simulation/chapter-31-fast-n-body-simulation-cuda https://developer.nvidia.com/gpugems/gpugems3/part-v-physics... edit: Here's a low-res animated GIF for anyone who doesn't want to click an instagram link: http://gregorywieber.com/assets/images/art/murmuration.gif http://gregorywieber.com/assets/images/art/murmuration.gif

afro88 7y ago
Love it, and the others on your instagram. You should start a dedicated account for them. I would like to follow your art, but feels weird seeing family photos of someone I don't know :/

miniatureape 7y ago

I posted this simple boid drawing toy a year or two ago: https://miniatureape.github.io/boiddraw/ https://miniatureape.github.io/boiddraw/

foreigner 7y ago

Good old Boids! I implemented a clone of Boids in C as my senior project in high school. It included 3D wireframe graphics from scratch. My teacher said it was "A nice screensaver".

escot 7y ago

> Incidentally, "boid" is also a New York Metropolitan dialect pronunciation for "bird".

banana-slug 7y ago

Nice boid-related tutorial: https://www.youtube.com/watch?v=bqtqltqcQhw https://www.youtube.com/watch?v=bqtqltqcQhw

timtimmy 7y ago

Boids are my favourite hello world for 3D simulation environments. For the last few weeks, I've been using boids to update my GPU programming skills and knowledge of related algorithms in Unity and Unreal. Yesterday I got 0.5 million boids simulating in Unreal Engine at 45 fps on a GTX 1080 [0]. The bottle neck is rendering so many instanced cone meshes, the simulation without rendering can do 1 million boids at 120 fps. I'm borrowing a common data structure used in GPU fluid simulations, the dynamic hashed grid, to calculate the neighbourhood of each boid (cool tutorial here with full source code [1]). We need the neighbourhoods to calculate their urges. My code is a mess at the moment, but if there is interest I can post it to GitHub (Unity and Unreal). Boids are an example of agent-based modelling and swarm systems. I used agent-based modelling in my PhD thesis to construct and simulate realtime, interactive 3D biomolecular models of mitochondria and neuromuscular synapses [2,3]. Now that I'm free (graduated), I'm building an iPad app to teach and communicate structural and molecular biology with immersive, and realtime simulations. Our vision is to make molecular and structural biology immersive and fun. It's not a textbook, it's a little more like Neil Stephenson's young lady's illustrated primer! :D [0]: https://twitter.com/timd_ca/status/1243941167005192192?s=20 https://twitter.com/timd_ca/status/1243941167005192192?s=20 [1]: https://wickedengine.net/2018/05/21/scalabe-gpu-fluid-simulation/ https://wickedengine.net/2018/05/21/scalabe-gpu-fluid-simula... [2]: https://prism.ucalgary.ca/handle/1880/111493 https://prism.ucalgary.ca/handle/1880/111493 [3]: https://youtu.be/6CsxADBpal0 https://youtu.be/6CsxADBpal0

banana-slug 7y ago
Here is a thematically-related boids simulation from 2006: https://www.red3d.com/cwr/papers/2006/PSCrowdSandbox2006.pdf https://www.red3d.com/cwr/papers/2006/PSCrowdSandbox2006.pdf Did 10,000 to 20,000 agents at 60 fps. Puny compared to yours, but not bad for 14 years ago! https://www.youtube.com/watch?v=Jpy5rJSVLj8 https://www.youtube.com/watch?v=Jpy5rJSVLj8 https://www.youtube.com/watch?v=ZZoy-8xK0YI https://www.youtube.com/watch?v=ZZoy-8xK0YI
- timtimmy 7y ago
  Wow. There are some great ideas in that paper.

robotresearcher 7y ago

Reynolds put up a page about Boids in 1995 and added links to related work for a few years. Great stuff. https://www.red3d.com/cwr/boids/ https://www.red3d.com/cwr/boids/

anoopelias 7y ago

Now who doesn't have an implementation of Boids of their own... :) https://anoopelias.github.io/boids/ https://anoopelias.github.io/boids/

postnihilism 7y ago
It's a classic :) I made a little framework for building these types of models: https://github.com/jrhdoty/SwarmJS https://github.com/jrhdoty/SwarmJS Here's a boids implementation using it: http://jrhdoty.github.io/SwarmJS/ http://jrhdoty.github.io/SwarmJS/

simonswain 7y ago

I did a browser based Boids version that simulated galactic colonization: https://coldwar.io/deepspace https://coldwar.io/deepspace and a simpler variant with predators: https://coldwar.io/predators https://coldwar.io/predators

dimovich 7y ago

My simple implementation in C / ClojureScript. https://dimovich.github.io/art/ https://dimovich.github.io/art/