F13LD.grain
Stochastic, non-periodic lattices grown from random fields — spinodoid wave superposition, Gaussian-random and hyperuniform fields, or reaction-diffusion. Pick a field model, bias its direction, then threshold it into a structure.
What it generates.
F13LD.grain builds bicontinuous, non-periodic structures by generating a random scalar field and thresholding it. Four field models are available, each with a distinct morphology, and the result can be biased toward a direction to make it anisotropic.
Use it for organic, foam- or spinodal-like architectures rather than repeating cells. For periodic surfaces, see tpms or wave; for procedural-noise structures specifically, see noise.
Random fields and thresholding.
A spinodoid field is the sum of many plane waves whose directions are drawn from a distribution on the sphere; thresholding it produces a spinodal-decomposition morphology. The concentration κ narrows that distribution to align the structure, taking it from isotropic to columnar.
The other models — Gaussian-random, hyperuniform, and reaction-diffusion (Turing patterns) — generate the field differently but are thresholded the same way. For high-N or reaction-diffusion fields, Section 2D previews the morphology before a full 3D build. Directionality connects to anisotropy & Zener.
Worked example: a spinodoid.
Pick the field
Set field type to spinodoid. The directional-bias controls below drive its morphology.
Set direction and disorder
Choose a Directional bias mode — Isotropic, Single, or Orthotropic — and set concentration κ (low = isotropic, high = aligned), with dir θ/φ for the orientation. N waves and RNG seed set the realization.
Threshold into a solid
Under Geometry, pick a topology — Sheet, Half-solid, or Solid — and set center and half-width to fix the volume fraction; smoothing rounds the surface.
Check the stiffness
Use Section 2D to scan morphology quickly, then Run homogenization for the effective stiffness. Aligned fields give directional stiffness.
Hand it off
Export JSON, or Open in F13LD.mesh.
Each control has an i in the tool that opens its reference entry. This page is the walkthrough; the in-tool guide documents what every control does.
Presets.
Field starting points to load and adjust.
spinodoid, Isotropic bias, many N waves. No preferred direction.
spinodoid, Orthotropic bias, high κ. Aligned and directionally stiff.
field type reaction-diffusion, Gray-Scott. A bicontinuous Turing maze.
hyperuniform, aspect 4–8. Elongated, rod-like cells.
Export and handoff.
F13LD.grain exports a recipe JSON — the field model and its parameters and seed, not a mesh. The same field regenerates exactly from the recipe.
Open in F13LD.mesh passes the recipe to mesh for a watertight 3MF. Note that stochastic fields can leave thin or barely-connected regions — check the mesh preview before printing.