Every one of these opens in the browser editor, running, with its node graph laid out for you to take apart. Nothing to install and no account needed.
An object that follows the mouse across a plane. The cursor ray is built in the graph and intersected with that plane, then an actor moves the object there on every tick.
geo/Actor code/CursorRay code/Plane code/RayPlaneIntersect
The tex/ReactionDiffusion node grows coral from a few blobs. A map changes the feed and the kill from left to right, so the blobs stay rings and dots on the left and branch into dense coral on the right, and a mask blocks a round rock in the middle, which the coral grows around.
tex/PolyNode tex/Builder code/Noise
The tex/ReactionDiffusion node grows a pattern from a star seeded in a picture: two chemicals spread and react, and the star becomes a maze of stripes. Other values of F and k give coral, worms, spots and holes.
tex/PolyNode tex/Solver tex/Builder code/TextureLaplacian
The tex/ReactionDiffusion node grows a pattern in a 64 by 64 by 64 texture: two chemicals spread through the volume and react, and three seeded spheres grow into a maze of folded sheets. The viewer draws them as fog with a mat/Volume, and beside it as a solid with a mat/VolumeSurface, both reading the texture where the GPU wrote it. Open the texture panel to see it slice by slice or raymarched.
tex/PolyNode tex/Solver tex/Builder code/TextureLaplacian mat/Volume mat/VolumeSurface