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Ultrathin business card runs a fluid simulation

github.com

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Re: Ultrathin business card runs a fluid simulation

#211

Post by animal531 »

delichon wrote: post #170

Advantages of a business card sized hollow box partially filled with water: * more realistic fluid motion * cheaper, easier build * easier to debug Disadvantages: * risk of wet butt when you sit down * less joy of doing hard things

I love good finger toys at my desk to keep my ADD busy while I'm working. They need to be:

- Light: If they make a clanking noise every 5 seconds when you pick them up and put them down its just distracting.

- Plastic: There are other materials that work, but in general metals and fabrics react too strongly with your fingers over time, whereas plastic can be easily cleaned.

Having a little water window isn't a problem, but the water is also not as directly cool looking. Usually in the '90s you'd get those mixed color oil/water toys where the colors would make them stand out more, but shaking them would mix the substances causing them to lose function.

As such the electronic version is quite durable in comparison.

Re: Ultrathin business card runs a fluid simulation

#212

Post by pornel »

raincole wrote: post #4

Off topic, but where should one start learning writing physical simulation? Several years ago I ran into this project [0] and got overwhelmed even the algorithm can be written in 88 lines of C++. I realized that out of all CS topics, physical simulation is probably the one I knew the less (not saying I'm a compiler/database expert or something, but at least I've implemented a toy compiler and some basic data structur…

For water simulation, look towards learning compute shaders.

Eulerian (grid-based) simulation is one of the classic examples.

Re: Ultrathin business card runs a fluid simulation

#213

Post by pornel »

The simple box-shaped container and low framerate/low gravity simulation doesn't show off what the FLIP algorithm can do.

The algorithm is a more expensive combination of two simulation methods to support both splashes and incompressibility, but the benefits are barely visible in the simple container.

Re: Ultrathin business card runs a fluid simulation

#216

Post by [deleted] »

kazinator wrote: post #209
N2yhWNXQN3k9 wrote: post #193

Earlier quoted context omitted.

increase viscosity of said fluid

It doesn't work that way, unfortunately. The virtual fluid represented by the LEDs does not move anything like syrup. It's like looking at a small image of water sloshing in a big tank. To get of fluid to behave that way on the scale of several inches, the fluid would have to be massive (very dense) while simultaneously gravity would have to be reduced.

[deleted]

Re: Ultrathin business card runs a fluid simulation

#217

Post by bullox »

kazinator wrote: post #209
N2yhWNXQN3k9 wrote: post #193

Earlier quoted context omitted.

increase viscosity of said fluid

It doesn't work that way, unfortunately. The virtual fluid represented by the LEDs does not move anything like syrup. It's like looking at a small image of water sloshing in a big tank. To get of fluid to behave that way on the scale of several inches, the fluid would have to be massive (very dense) while simultaneously gravity would have to be reduced.

> the fluid would have to be massive (very dense) while simultaneously gravity would have to be reduced.

/joy of doing hard things intensifies

Re: Ultrathin business card runs a fluid simulation

#218

Post by wedesoft »

kazinator wrote: post #209
N2yhWNXQN3k9 wrote: post #193

Earlier quoted context omitted.

increase viscosity of said fluid

It doesn't work that way, unfortunately. The virtual fluid represented by the LEDs does not move anything like syrup. It's like looking at a small image of water sloshing in a big tank. To get of fluid to behave that way on the scale of several inches, the fluid would have to be massive (very dense) while simultaneously gravity would have to be reduced.

You can use two different fluids instead of water and air.

Re: Ultrathin business card runs a fluid simulation

#219

Post by mhb »

delichon wrote: post #170

Advantages of a business card sized hollow box partially filled with water: * more realistic fluid motion * cheaper, easier build * easier to debug Disadvantages: * risk of wet butt when you sit down * less joy of doing hard things

Starting point: Ocean waves in a bottle

https://www.youtube.com/watch?v=W4jbx5WLhy4

Re: Ultrathin business card runs a fluid simulation

#220

Post by pfortuny »

delichon wrote: post #170

Advantages of a business card sized hollow box partially filled with water: * more realistic fluid motion * cheaper, easier build * easier to debug Disadvantages: * risk of wet butt when you sit down * less joy of doing hard things

It also solves a fluid mechanics problem much faster and more accurately than de digital one!
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