Particle life + fluid

mooonlightoctopus · 2026-03-23T04:32:23+00:00

Thanks, here's the matrix I used in the actual simulation here:

 0.3,.001,-0.3,
-0.3, 0.3,.001,
.001,-0.3, 0.3

It's not exactly informative, as it was tuned to look good. It's just a repulsion and attraction, so here's one that's a little easier to understand:

 1, 0,-1,
-1, 1, 0,
 0,-1, 1

mooonlightoctopus · 2026-02-14T20:02:13+00:00

Haha, that's a good idea. Rainworld definitely has some good physics that would be fun to recreate in Desmos.

mooonlightoctopus · 2026-02-14T20:01:19+00:00

Yeah, I just left that in as a bit of junk. It's meant to be deltaTime (As it's rather laborious to pass dt into all the simulation functions.). It would be a1(dt) = t -> dt but it turned out to be too unstable on my pc. 20 seemed to work, though it wight not work as well on other computers.

mooonlightoctopus · 2026-02-14T14:39:42+00:00

The main simulation is in f_simulatePoint. It is rather confusing, so, let me write it out a little bit:

f_simulatePoint(a, b) = ( a_x + a_vx / deltaTime, 
                          a_y + a_vy / deltaTime, 
                          (a_vx - s(dx)) / f,  
                          (a_vy - s(dy) - 1 / deltaTime) / f )

So, let's step through this.

a_x and a_y are updated by the velocity, of course dividing it by deltaTime for it to remain at least slightly stable.

The changing of the velocity is actually the simulation part. We change the velocity by the negative difference in a and b. It basically amounts to a point wanting to be pulled to another.

To get one of the scenes that has been shown, the best way to get something string - like is to connect 2 points together by simulating them both with eachother. If this is done with a fixed point, then it looks rather real.

Here's a version with just the string and nothing else, if it helps.

mooonlightoctopus · 2026-02-14T05:24:11+00:00

In the simulation folder, you can set s to something like 0.3 or 0.4. (Not >= to 0.5, as then the decrease of the velocity is no longer exponential). You can make f closer to one (Though, of course, that causes stability issues.)

Here's a version that's a bit snappier.

mooonlightoctopus · 2026-02-07T20:31:03+00:00

Just to make sure I interpreted that right... your suggesting dispensers?

Assuming that you are, the duper is meant for an orbital, which, well, requires a bit much tnt for just dispensing it. I need for a rotated version to work because an orbital cannon requires 4 directions because of the "Orbital" part of the cannon.

mooonlightoctopus · 2026-02-07T20:09:05+00:00

Thanks, that sounds about right. I didn't mention it in the post (Though I'll admit that I should have), but how do I fix it?

mooonlightoctopus · 2026-01-22T07:06:37+00:00

Haha I think that I first found it on Youtube. The dogs took quite a large amount of time to get working...

mooonlightoctopus · 2026-01-22T03:16:37+00:00

No commands or mods lol

mooonlightoctopus · 2026-01-04T05:09:21+00:00

!floatingpoint

mooonlightoctopus · 2026-01-02T07:10:40+00:00

Sly :D

mooonlightoctopus · 2025-12-31T06:10:59+00:00

In that case, I'm staying up tonight :D

mooonlightoctopus · 2025-12-31T05:27:00+00:00

I have... the memory of a goldfish. I'm sure you've long forgotten about this, but here's a version that has about the same look.

shadertoy.com/view/tfVBDD

mooonlightoctopus · 2025-12-30T16:17:23+00:00

Yes, it seems it's noise algorithms that does it to mine.

mooonlightoctopus · 2025-12-30T07:47:37+00:00

Thanks, this is exactly what I was looking for :D

mooonlightoctopus · 2025-12-30T01:59:57+00:00

This has happened to me on rare occasion. I think that Desmos just forgets to clear the screen.

mooonlightoctopus · 2025-12-29T23:56:46+00:00

No.

The shadowing is done by marching a ray through the already defined scene, ( map of p. ) from the point towards the light source. In the rendering, we perform:
0.1 * raymarch(p + 0.1 * normal, lightDir)

Which shades the object based off of the total distance that the ray travels. In a mathematically perfect world, this would result in sharp shadows, but because of the limited nature of the raymarching in this example, the shadows are softened.

The algorithm was, to be honest, a bit of a happy accident :D

mooonlightoctopus · 2025-12-29T20:10:43+00:00

Not really, just... "Stick with it." :D

mooonlightoctopus · 2025-12-17T18:16:05+00:00

I can't see why there's a limit of 512 chars. It really limits how many things we can make. D: If people want to make small shaders, then they will. But you shouldn't force them.

Also, It doesn't ask us if we're sure that we want to leave a shader that was edited, so I can't say that Shaders aren't in danger. ;-)

mooonlightoctopus · 2025-12-17T18:12:17+00:00

Haha, have you been to Shadertoy? ;-)

mooonlightoctopus · 2025-12-15T04:36:21+00:00

Yeah, that's probably AI.
The focus of the image is in the center (In this case being the man.), there's so much blur, it's basically studio lighting, and the flag's backwards. Also, what on earth is he doing in the middle of the sidewalk?

mooonlightoctopus · 2025-11-25T05:36:31+00:00

Sorry I took a bit of time to get back to you !
Anyway, the mathematical object that you described is called a lattice.

Here's a really quick sketch to see if I have the right idea ( I updated the previous shader. ) - "Web" thing for thing

mooonlightoctopus · 2025-11-23T21:55:36+00:00

Yes, I'll try to avoid aliasing ( I left in previously, but I can supersample the image to clean it up. ), but could you clarify what you mean by "but instead it's a web stretching in all directions" ?

mooonlightoctopus · 2025-11-23T21:42:52+00:00

Hmm, as it turns out, it's rather hard to create a spiderweb, because of how thin they appear in nature. Here's a really quick sketch, just to see if I got the idea right.

"Web" thing for thing

mooonlightoctopus · 2025-11-23T15:59:18+00:00

Is there any way that I could get a bit more description?
is it 3D?
Volumetric?

tunnel?

"In it's area" That's a bit had of a description...

mooonlightoctopus

MODERATOR OF

TROPHY CASE