Help Chemical reactions

[bogdanTNT]

I bought obi fluid a couple of days ago and I still have not figured out how to make chemical reactions like in the video demo. There isn't even a demo scene to test.

Guys, send help pls

[josemendez]

I bought obi fluid a couple of days ago and I still have not figured out how to make chemical reactions like in the video demo. There isn't even a demo scene to test.

Guys, send help pls

Yes there is a demo scene included, it's called "FluidMixing". Set up two fluid materials, give them different diffusion data values (there are 4 channels that can be used for diffusion, the sample scene only uses the first one). Also set the "diffusion" property to some low value, e.g. 0.002. This controls the diffusion/reaction speed.

Then, write a script that gets the "userData" values for each particle and maps the diffusion data to color, viscosity, density, or any other particle property.
The sample scene uses the "ObiFluidPropertyColorizer" sample script, which maps diffusion data to a color using a gradient.

kind regards,

[bogdanTNT]

Thanks man

[Charlie Rubio]

Yes there is a demo scene included, it's called "FluidMixing". Set up two fluid materials, give them different diffusion data values (there are 4 channels that can be used for diffusion, the sample scene only uses the first one). Also set the "diffusion" property to some low value, e.g. 0.002. This controls the diffusion/reaction speed.

Then, write a script that gets the "userData" values for each particle and maps the diffusion data to color, viscosity, density, or any other particle property.
The sample scene uses the "ObiFluidPropertyColorizer" sample script, which maps diffusion data to a color using a gradient.

kind regards,

 Hi! I was wondering if there could be a feature for Obi Fluid that could mix 2 or more particle properties into a single particle. This could simulate a lot of chemical reaction based on molecular changes. I've been playing with ObiFluid for a couple of weeks and Im fastinated with its potential since all seems to work in an organic way. This is the hardest aproach to Unity from physics concepts that I've seen this far!

[josemendez]

 Hi! I was wondering if there could be a feature for Obi Fluid that could mix 2 or more particle properties into a single particle. This could simulate a lot of chemical reaction based on molecular changes. I've been playing with ObiFluid for a couple of weeks and Im fastinated with its potential since all seems to work in an organic way. This is the hardest aproach to Unity from physics concepts that I've seen this far!

Hi there,

I suppose you're talking about volume fraction based approaches, where each particle carries a "percentage" of multiple fluids. We use a very simplified approach where each particle has 4 channels of  "data" that is diffused with neighboring particles, you can use these channels to drive density, viscosity, color changes, etc, even in non-linear ways. Check the "Raclette" sample scene, where we drive variable viscosity based on the diffusion of one channel that changes on contact with different surfaces.

We've looked at more accurate models before (volume fraction, helmholtz free energy) but it is unlikely we will implement them in the future as they're more performance demanding, and Obi is designed for realtime applications.