Cloth Simulation
180 points
7 days ago
| 18 comments
| cloth.mikail-khan.com
| HN
clbrmbr
8 hours ago
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The tearing was unexpectedly disturbing!

Suggestion: use an accelerometer data on mobile and use that to directly replace gravity. I expect to be able to tip the phone to drape the cloth, and shake the phone to get waves of motion.

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eddieroger
4 hours ago
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I think the little tears were fine, but my expectation of the weight of the cloth wasn't so much that it would start to rip on its own after a certain point. It felt more like a wet dough at a certain point than cloth.
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Hobadee
7 hours ago
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This.

I can tear real cloth if I try, but I need to try. A flick of the finger has never once in my life torn cloth.

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fainpul
6 hours ago
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Literally unplayable
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brookst
4 hours ago
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It feels a bit like shooting at cloth.
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afandian
6 hours ago
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Clear you must bite your nails!
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cloudfudge
3 hours ago
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It's rust compiled to wasm. Dude's got a lot of interesting stuff on his projects page: https://mikail-khan.com/portfolio
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OptionOfT
5 hours ago
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I remember the first time playing Splinter Cell.

Walking back and forth through a curtain to see how it wraps around the body. So cool.

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raylad
1 hour ago
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Feels more like a spiderweb simulation. The fibers are sticky and stretchy.
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jeffreygoesto
10 hours ago
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For me, "Large Steps in Cloth Simulation" [0] made implicit methods accessible... Seminal paper.

[0] https://dl.acm.org/doi/10.1145/280814.280821

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chombier
4 hours ago
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For inextensible cloth there's also "Efficient simulation of inextensible cloth" [0] that is particularly clever and efficient

[0] https://dl.acm.org/doi/10.1145/1276377.1276438

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atan2
11 hours ago
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A very nice article by Marian Pekár on Verlet integration and cloth simulation:

https://pikuma.com/blog/verlet-integration-2d-cloth-physics-...

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bogtog
8 hours ago
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It tearing when I waved my mouse around was a nice surprise
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jakemanger
2 hours ago
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That's super cool (and FAST -> hard to do from my personal attempts).

But, please, give us some nitty gritty of how you made it

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taeric
5 hours ago
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First, kudos on this. Really cool to play with.

Reminds me of a great video not long ago that went over the main ideas behind weaving and knitting. Feels like you almost certainly have to take some of those ideas in mind when doing a simulation like this. Would be curious to read a breakdown of how this was made and how it incorporates the concepts that go into different fabric.

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LyalinDotCom
4 hours ago
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I was curious and was able to build something very similar quickly using Gemini 3 via Google AI Studio. Never would have imagined a few years ago how easy some of this has become to prototype.
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cyber_kinetist
4 hours ago
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There's a lot of simple cloth sim examples on the internet, so I see why LLMs can code these kinds of demos easily.
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LyalinDotCom
3 hours ago
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yeah makes sense. Im sitting here evolving my little prototype its too much fun.
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jcims
2 hours ago
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The 'Build' feature in AI studio has been pretty incredible for a few use cases I've thrown at it.
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hoppersoft
3 hours ago
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I spent entirely too much time finding out exactly how much "cloth" could be supported by two "strings."
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zenoprax
3 hours ago
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I'm going to assume it is "more than you think; not as much as you'd like" because I don't have the time to burn this morning to replicate your research.
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samcheng
5 hours ago
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This is great! The only part that broke the immersion (for me) was that the cloth bits fell at a constant rate - I'd expect them to accelerate due to gravity, and maybe flutter as they fell.

Nice art!

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Miraltar
11 hours ago
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Exactly as discussed in Sebastian Lague's video https://www.youtube.com/watch?v=PGk0rnyTa1U
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TwoFx
11 hours ago
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I highly recommend watching the relevant section of that video (4:38 to 8:59) and then implementing it yourself in whatever system you know that can draw lines and circles (I did it in Godot; it took only a few minutes to learn enough Godot to start on the algorithm).

It's absolutely mind-blowing that so little code can produce such a beautiful result. It's also fun to play with the parameters and see how they affect how the cloth feels.

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mclau153
5 hours ago
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would you share your godot code to github?
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RankingMember
5 hours ago
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Pretty cool! I kept trying to cut the piece I had just cut again by doing a "Zorro"-style motion, but no such luck.
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robertheadley
4 hours ago
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I wonder how far away we are from realtime Marvelous designer in games.
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mrkramer
4 hours ago
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Reminds me of Fruit Ninja but this one is Cloth Ninja.
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iberator
11 hours ago
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Maya and Cloe 3D and almost all fashion design software have it for decades already. Niche and fascinating software. Check out some demos.

Cool stuff in software you don't even know exists:)

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zokier
9 hours ago
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Of course cloth sims of varying fidelity are everywhere. Even games have had cloth sims for decades at this point.

But it is also something that remains a research problem how to do efficiently and with good results; pretty much every year in siggraph you see couple of new papers around cloth sims. For example this year we got this https://youtu.be/d9TZhtXeMio

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ChrisMarshallNY
8 hours ago
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As an artist, I needed to get it right. Wasn't as easy as I thought it would be. I had to think in 3D, to make 2D.

https://littlegreenviper.com/art/Tarsus.png

https://littlegreenviper.com/art/Gym.png

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fao_
8 hours ago
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One of the best ways to practice this is just throwing a towel on a chair, sitting down opposite it, and sketching it
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regularfry
7 hours ago
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The cloth sim in Blender remains one of the most frustratingly un-updated features. I would dearly love to see it get an algorithmic refresh.
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brontosaurusrex
6 hours ago
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At least solver seems faster (if not better) in later versions? p.s. My try at 'flag in the wind' in Blender from around 2022: https://0x0.st/s/aJ6DNj2pEHzRdBiscEIsbQ/KCsK.mp4 I do remember it took me all day to get somehow realistic motion.
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jan_Sate
7 hours ago
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Looks like that I can cut it without right click by swiping fast enough.
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