L-system Graphics vs Reaction–Diffusion
L-systemグラフィックス / 反応拡散パターン
Both sit in Computational Expression, so the question is not what they belong to but how they behave. They are reached for with some of the same intent, which is where they get confused.
L-system Graphics
L-system graphics rewrite symbol strings in parallel and interpret them as drawing, turning a few rules into recursively growing plants, trees, mycelia and ornaments.
Reaction–Diffusion
Reaction-diffusion simulation lets substances react locally while spreading at different rates, self-organizing small disturbances into spots, stripes, mazes and coral-like patterns.
| L-system Graphics | Reaction–Diffusion | |
|---|---|---|
| Era | 1968– | 1952– |
| Family | Computational Expression | Computational Expression |
| Kind | Technique | Technique |
| Cues | Branches repeating one angle rule from a trunk / Self-similar detail increasing by generation / Leaves or flowers attached regularly at tips and joints / A growth grammar that survives controlled randomness | Round spots dividing at even distances / Continuous curving maze stripes / Coral or cellular boundaries branching from edges / Self-organized marks of nearly constant thickness |
| Best used for | Modeling plant growth in education, visualization and generative motion · Making reproducible branching patterns and ornament from a small rule set | Explaining biological spot and stripe formation in research, education and exhibitions · Growing organic surface, motion and type patterns |
| Type | Set rules and generation numbers in monospace outside the generated form. | Place copy in low-density regions instead of eroding every letter with the pattern. |
| Composition | Anchor one root and plan how each generation expands into the available field. | Show growth from a seed or boundary condition rather than freezing a uniform all-over print. |
| Material | Define symbols, productions, angle, line length and stack operations, updating all symbols in parallel per generation. | Set reaction terms, diffusion rates, feed and kill rates, then iterate from a small perturbation. |
| Caution | Mirroring branch photography is not an L-system. Preserve the production rules that generate each generation. | A hand-drawn animal print is not reaction-diffusion. Time and parameter changes must remain visible in the pattern. |