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Don't have any substantial comments, but I must say that the result is really impressive. Just wow.
That's some National Geographic clip. Now, show us the demo!
2 of the linked references have full implementations of very similar things, with some shared references.

Is there something here which godot is enabling which wasn't previously possible? It seems to be entirely GPU compute workload with particles which are available as part of all mature rendering engines

Godot itself is open source, which I think has brought a strong community of people to it. My mega-big-ultra project I've been working on since 2013 would be nowhere near as close to where it is now (close to launching crowdfunding/alpha) if I hadn't transitioned to Godot! (I was fighting the UE4 system from the days when it was $20/mo, we linux people really got dealt dirty by Tim Sweeny, with lots of empty promises for linux support)
Looks incredible!
The sample video is really impressive, it's worth a peek.
20 years ago I could spend months tweaking ocean surface in renders and not get even close to that. Amazing how good this is!!

Although the demo clip feels a bit exaggerated (saying this having over 50k Nm open water ocean sailing in my logbook). Waves that sharp and high would need the wind blowing a lot stronger. But I am sure that is just a parameter adjustment away!

Since it is in Godot I assume the rendering is real time? Does it need a monster GPU?

There's 2 demo clips, the second one shows quite a number of parameters you can adjust.
I think the point is that these parameters you adjust are being rendered near real-time, whereas back in their days you’ll have to enter these values, and add custom tweaking because the hardware just wasn’t powerful enough to do the things we can do now at many times the speed. Not to mention the vast improvement in mileage for your time.
yeah, the "in real time" is what kills me. the old joke of blue bar races, rendering, buffering, and any of the other things us gray beards had to put up with is just unimaginable to the whippersnappers of today.
Back when I graduated, doing particle engines, with marching cubes and stuff like that, was a graduation thesis project.

Nowadays it is a check box on a game engine, one of many.

People don't imagine how good they have it with modern engines.

Not to take any value out of this work, this is a great achievement and kudos to the author, only making the point how good we have nowadays.

Back when I graduated I was still holding my breath for the patent expiration on marching cubes, GPUs were still being made for PCI and even ISA slots, you could find some game engines but you would have a better time writing one specialized for the type of game or graphics you were targeting.

Things really have improved a lot.

I guess we might have a similar age, first computer Timex 2068. :)
sounds like it, my first computer was an Atari 800 XL that shared the family TV as its monitor (and fortunately there was an RF switch to toggle between it and the antenna so we worked out a kind of timesharing system)
Sounds familiar. :)
> I could spend months tweaking ocean

I have a game project. But I always get nerd sniped by cool game stuff, and want to implement them myself. My progress so far could probably have been achieved in a 48h gamejam if I just used/bought existing assets. Instead I have also spent weekends playing with water shaders and getting them to look how I want.

But my game is a puzzle game. I don't need water, except that I now have a cool splash screen..

You might be taking "splash screen" a bit too literal.
Agree, based on the clips, it looks a bit random.

I think it is looks to be very good, and probably the best I’ve seen having given it a cursory search recently to see what was possible.

In terms of what I’d like to see, open ocean waves generally have more rhythm, I’d be very interested to see a simulation of 15 knots of wind blowing over 1km for a few hours and see if that matches what I observe, which would be relatively organised wave trains (sets) that build and disperse.

This is not a criticism, just an observation: it looks like what I imagine an ocean of hot corn syrup would look like (after dyeing it blue). The viscosity seems right; possibly the surface tension is not what ocean water would have (a colloid of salty H2O and biomaterial, which is common in real-world experience but quite ugly for computational fluid dynamics).

Also note that the ocean spray here is a post-hoc effect, but for a real ocean the spray dulls the sharpness of the waves in a way that will be (vaguely) apparent visually.

Of course there's almost no "physics" in this elegant, simple, and highly effective model, so I want to emphasize that suggesting directions to poke around and try things should not be construed as an armchair criticism.

This is literally a criticism.
A) It would be a criticism if I thought these effects could be plausibly rendered with a similar FFT algorithm, but that seems unlikely to me. I think these results are "highly effective" given the toolset, which is not attempting to emulate the actual physics.

B) This project is not an all-out attempt to make lifelike water, it is described as an experiment. I am making an observation about the result of the experiment, not criticizing the project for failing to meet standards it wasn't holding itself to.

Neat that FFT yields great waves.

But ultimately, does that model model vortexes or other fluid dynamics?

Can this model a fluid vortex between 2-liter bottles with a 3d-printable plastic connector?

Curl, nonlinearity, Bernoulli, Navier-Stokes, and Gross-Pitaevskii are known tools for CFD computational fluid dynamics with Compressible and Incompressible fluids.

"Ocean waves grow way beyond known limits" (2024-09) https://news.ycombinator.com/item?id=41631177#41631975

"Gigantic Wave in Pacific Ocean Was the Most Extreme 'Rogue Wave' on Record" (2024-09) https://news.ycombinator.com/item?id=41548417#41550654

Keep in mind that this project is aimed at video game developers, not oceanographers :) The point is to get something cheap and plausible, not to solve Navier-Stokes with finite element methods.
criticism can be positive, neutral or negative.
This not a criticism, but the comment you are replying to is a critique, not a criticism.
What sad times do we live in, that you need to defensively remark you're not making a criticism as if criticism was bad?

I found a video that records (in a few places) how the waves actually look: https://www.youtube.com/watch?v=8XBO-hen7_s

Maybe you can adjust the parameters of the tool to get waves like this, or perhaps I still should care even if the solution isn't realistic, and getting such an effect is hard by just using an arbitrary formula. In particular getting the detail right, but I imagine the recorded video is heavily subdivided and takes most of the resources that you just can't spend on a real video game.

It's still impressive, but I can't help but wonder why the formal maths if you don't arrive at anything realistic - perhaps because I'm a layman and I don't understand the difficulties of achieving this.

20 years ago I could spend months tweaking ocean surface in renders and not get even close to that.

I'm not sure what you mean here, because this is made directly from research that was done 20 years ago and it looks the same, it's just being done in real time.

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The demo looks unrealistic. The waves never break. Increasinlgy steeper slops with pointy peaks travel from left to right until they just sink down towards the left.
This is explicitly a simulation of ocean waves, and ocean waves do not break.
Okay. That makes sense. What about the steep elevation? Shouldn't it be smoother at the top?
it should curve at the top, its too pointy. this example looks like mountain peaks and not wave peaks. also the color should be patchier somehow when zoomed out, with darker blue gradient. otherwise I like it/ its almost convincing
As someone who has done offshore sailing… the waves also look unnaturally steep/tall/pointy to me. It’s very cool, but needs some tweaking still.
I spent years living on the beach. When you live on the beach, you watch the ocean for hours at a time because it’s mesmerizing and feels sensational. I wouldn’t guess for a second this was a render.
I live on the beach now and I have a view about 14 stories above the water also- and somehow its clear to me its fake. Its missing the dark patches from wind gusts and the white parts are going straight up instead of curling even lightly. otherwise it seems pretty real
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Have you actually looked at waves and how they move, though? If you've spent years living on the beach you'd be able to spot in a heartbeat that the formation of foam and movement of the wave is not natural.
Other observers said the same thing so apparently I didn’t look as carefully as I thought I did!

> If you’ve spent years living on the beach, blah blah blah

I wish I gave a flying fuck about your not very subtle accusation. Feel free to believe what you want. I’m retired and I still don’t have as much free time as you do. You are not very good at mind reading, but I’m glad you’re giving the old college dropout try.

20k hacker news karma says quite a lot more free time than a couple hundred though
Yet somehow I held down multiple jobs simultaneously, care for a severely handicapped child, support an extended family, and keep up my technical skills even in retirement while other people are staring at TikTok in line at Starbucks. Maybe it says something about time management. Stay classy
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That looks wet. And honestly it is the best compliment I can give.
i live by the sea and have a sea view. when a gust comes through to stir seadogs the color is darker in patches where there is wind in small areas. You cant havr choppy weather without some of this patchy color. also the white chop never goes straight up as in the videos, but it curls at least slightly.
It is very impressive, and better than anything I've seen before but think something is bit off with the swell. If I had to explain I would say that high frequency waves don't travel on top of low frequency waves the way they do in the video.
While I appreciate ever more realistic water bodies, the part that game makers really struggle with is where the water encounters an obstacle.

I did not see any mention of this in the description. Conceivably though, this is not a huge conceptual leap right? A game maker would simply need to add logic to impact the frequencies near objects, no?

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The referenced paper "Simulating Ocean Water" talks about this in section 5. Indeed the FFT approach makes this difficult, where a different approach[1] for waves reflecting off obstacles.

That approach uses convolution, however you can perform convolution using FFTs[2], so perhaps there's some nice way to combine the two approaches.

edit: I just skimmed the papers, and it seems[1] does indeed mention combining the FFT approach with the convolution approach in the section on Ambient Waves.

[1]: https://people.computing.clemson.edu/~jtessen/reports/papers...

[2]: https://phys.uri.edu/nigh/NumRec/bookfpdf/f13-1.pdf

To an extent you can get away with just sampling the output of the water shader to work out the water's effective height at any given point. Big changes in height, or buoyancy for non-static objects, indicate bigger angles hitting the waves and you can fake some splashes with particles while the wave itself just gets occluded. Apply forces at just three or four points and you can make a boat rock pretty believably on top of this kind of water.
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Oh my - this is great!

Does it mention what the density of the mesh is, or is it a flat plane with no displacement?

Also, I wonder if there's a way to optimise the foam particles in some way. It does seem very wasteful to generate them across the whole plane, when most are culled. I wonder if the particle emission / creation could be linked to foam density?

This is beautiful, I'd love to have this as a lockscreen or even a screen panel on a wall somewhere
The other two Godot repos by this person are very interesting as well. I love the level of detail they add to explaining their repos. This one is particularly interesting: https://github.com/2Retr0/GodotGaussianSplatting

Wonder if they are a student, they seem to cite other work frequently and have a strong grasp on recently published materials.

> Wonder if they are a student

Seems like they might be.

One of their repos has this title and description:

> ENGR96A-coursework

> Relevant coursework for ENGR 96A Introduction to Engineering Design F23

And F23, judging by the dates of the commits in that repo means Fall 2023.

Of course, it could be that this and other UCLA courses referenced in the repos are open for everyone. So maybe you don’t have to be enrolled as a traditional student at UCLA to take them.

Things like this brought me into computers, but along the way I fell for the easy and boring life of glueing libraries, endpoints and corporate bullshit that leads to burnout. Perhaps some day...
Someday could be today...
There are only two good moments to plant a tree: 20 years ago and today.
Isn’t it like: the best time to plant a tree is 20 years ago. The next best time is today.
Though I never understood why 19 years ago wouldn’t be the second best…
That would make today the worst day to plant a tree?
The worst so far, and the best when compared to all of your remaining days.
Because the statement is meant to motivate the reader.
Because you didn't think of it then.

You thought of it 20 years ago and didn't do it, and you're considering it again now.

Instead of telling yourself it is too late to do it now, just go for it, so that in 20 years more you will be happy you planted this tree.

Also some people like their children and grandchildren to enjoy some fruit trees.

(Even if they are just "family" in the broader sense and not their own)

Yes that’s it, thank you. I’ll admit I was too lazy to look the exact one up.
15 years ago was probably pretty ok too
My problem is I'm so burnt out from the aforementioned stuff I don't have the motivation or energy for the cool stuff anymore. I feel like I need a year long sabbatical first, but reality says otherwise.
Sounds like you just need more coffee :-D
More coffee, maybe a pizza party. That'll fix me right up.
Same here, this has been the central crisis of my working adult life for 25 years. Unfortunately it never gets better. And I've taken 6 months to 1 year off for severe burnout with physical symptoms like adrenal fatigue twice now.

My feeling is that this problem is intractable alone. We need groups working towards liberation, and societal change to support healthy work/life balance.

What that looks like in practice is that wealthy people, especially those who won the internet lottery, should start giving something back. At the most basic level, that's paying one's taxes. Beyond that, they should start setting aside ego-based goals and start accepting requests outside of their attention so that the most pressing problems facing humanity can finally get solved.

Give a billionaire $1 billion and a year later they'll turn it into $2 billion. Give one of us $1 billion and a year later a form of cancer will be cured. That's why they have the money and we don't, and why it takes so long for things to get better, if they ever do.

If you can afford it (time/family/financially) I would say to do it. Even if it’s only 6 months. You can learn a LOT in 6-12 months if you’re disciplined and focused. Don’t forget to build up a network in any new endeavor you take, it will save you time, give you inspiration, and help get a job later on, and maybe you can help them along the way as well.
Make that day today! I’ve realised this same problem too, sure there’s some beauty in an ultra tight gluing of logic … but there’s a vast unexplored sea of programming beauty waiting to be discovered. I realised this over the weekend, so I’m diving into graphics programming.

I’m rooting for you!

I think make the move gradually - find the stuff you were excited in originally, that you would love to learn more about and eventually do. Spend maybe a few hours a week diving into it - then gradually increase and move away from your current job.

Go for it - we're all rooting for you!

I see a lot of my friends making more money than me doing stuff like that but I followed my interests and went into robotics first chance I got and do not regret it. There is nothing like the feeling you get seeing your code really interact with the world, at least speaking for myself.
I think the downside of this approach is you can’t ie split the waves with a ship.
Yeah I wondered how that could be done, otherwise this would only be good for backgrounds.
Great! I've shared this with every physicist I know who's not directly involved in animations.

Quick question from my swimming class yesterday: We know that professional swimmers use a range of technologies, both old and new, in their training. Is there currently a model that fully simulates the physics of swimming across different styles? If not, this seems like a great project idea!

Fourier was measuring tidal waves when he came up with wave frequency transforms - so in a way this is almost a full circle.

Very impressed!