2D Reaction Diffusion to 3D

Here is a script replicating some of the work presented on http://toxiclibs.org/2010/02/simutils-grayscott/ especially replicating this image http://toxiclibs.org/wp-content/uploads/2010/02/typeform_square_680...

Size of patterns depends on Grid size.

Time of calculation depends on grid size, _n_steps*jumps.

Image above was done using this script and bend, taper ... from Rhino, and also modifying feed and kill rates. See http://www.karlsims.com/rd.html

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Laurent DELRIEU

Here is the script to generate the guéridon "http://www.grasshopper3d.com/photo/reaction-diffusion-gueridon".

Almost all values used on the simulation are on a square grid. Here with 201 points in X and 201 in Y. So 40401 points.

A species concentration is set to 1 on all the grid

B species concentration represent the feet of the gueridon. Black mean 0 and  white mean 1.

A diffusion is set to 1.

B diffusion is set to 0.4 multiplied by the value of brightness (here 0.65 to 1) so B diffusion from 0.26 to 0.4. A lower value of B diffusion mean smaller size of pattern

Feed values are set to 0 (no B species in theses places) to 0.056.

Kill value is constant 0.0649.

N steps of jumps is the number of slices (minus 2) of the 3d model so here there are 201x201x202 = 8160002 provided to isosurface. Each slice is separated by jump*dt (18 here).

The script provided generate in less than 2 minutes the gueridon, with a mesh of 1,200,000 faces.

The mesh must be flipped in rhino. I also use CageEdit to deform the mesh for my rendering.

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Giovanni DeAmbrosio

Hello Laurent ! great job for your amazing work on reaction diffusion !

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Henry

This is pretty awesome! I'm new to grasshopper. How do you make the model in 3D? If I change the values in the script then only the pattern red and yellow 2D plane changes

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