grainNoise
One octave of smooth signed noise along and across a direction, for grain.
grainNoise(
coords: {along: Expr; across: Expr},
opts: {freq: [Expr | number, Expr | number]; offset?: [number, number]; drift?: Expr},
): Expr
Import materials from shaders/std and use materials.grainNoise.
coords come from directionFrame(...).coordsOf(p). freq sets the feature density per axis (a high across value gives fine streaks). Returns roughly −1 to 1. Sum octaves and apply gains at the call site.
Parameters
| Name | Type | Notes |
|---|---|---|
coords | {along: Expr; across: Expr} | |
opts | {freq: [Expr | number, Expr | number]; offset?: [number, number]; drift?: Expr} |
Example
const sheen = grainNoise(brush.coordsOf(pat), {freq: [1.3, 6.5], drift: driftA})
See also
surfaceNoise— Smooth signed noise at a 2D point, roughly −1 to 1, with features about one unit wide.tiltNormal— Tilts a normal along and across a direction, for brushed or woven relief.smearAlong— Blurs any 2D lookup along a direction, for streaked reflections and motion smear.