Fractal noise generator that inverts and squares each octave to produce sharp ridged veins and creases.

The Ridge Noise node generates fractal noise where each octave is inverted and squared, concentrating detail into thin, sharp ridges. It reads like veins, cracks, or mountain crests where FBM reads soft and Billow reads puffy.

Ridge Noise default output

One texture output; two optional texture inputs (domain warp and composite)
Fractal controls (Octaves, Persistence, Lacunarity) plus the standard transform block
Found in nerdGRAPH under Generators as Ridge Noise

Example patch — drag onto the app to load

The image on the right is the example patch itself — drag and drop it onto the app (or load it with File → Load) to open the full graph.

Inputs and outputs

Ridge Noise node

Port	Type	Purpose
Input	Texture	Domain warp — the red/green channels displace the noise sample coordinates
Composite Input	Texture	Composited over the output using the node's Blend Mode and Opacity
Output	Texture	The grayscale noise field, normalized to 0–1

A black (or disconnected) Input produces no warp; the warp strength scales with Scale.

Parameters

The field is sampled with time on a third axis, so animation evolves the pattern in place rather than scrolling it.

Opacity, Blend Mode, ALPHA, Invert Alpha, Threshold Min / Threshold Max — the standard operator header; see Perlin Noise for details.

Structure

Octaves (1–8, default 3) — how many noise layers stack. Each octave adds finer ridges; the default of 3 keeps the veins bold.
Persistence (0–1, default 0.5) — how much each successive octave contributes. Higher values add fine secondary ridges branching off the main ones.
Lacunarity (1–4, default 2) — the frequency multiplier between octaves. Higher values space the ridge scales further apart.

Transform

Seed (0–99999), Scale (0.01–10, default 1), Scale X / Scale Y (0.01–50, default 5), Offset X / Offset Y (−20 to 20), Rotation (0–360) — the shared generator transform block: seed picks the field, scale sets frequency (Scale × Scale X/Y per axis), offsets pan, rotation spins around the center.

Dynamics

Speed (0–5, default 1) — playback rate multiplier for this node, compounding with the global animation speed. 0 freezes the pattern.

Every slider has a per-parameter animation bar, so any of these can be animated, audio-driven, or MIDI-mapped — see Parameters and Controls.

Ridge vs. FBM vs. Billow

All three stack the same octaves and share the Octaves / Persistence / Lacunarity controls; they differ in what each octave contributes. Ridge inverts and squares it (sharp creases), FBM adds the raw value (balanced, natural), and Billow adds its absolute value (rounded, puffy). Pick by the feature shape you want.

Troubleshooting

The pattern doesn't move — the node's Speed is 0, or global animation is paused in the top bar.

Ridges look thick and blobby — lower Persistence or reduce Octaves; too much fine detail fills the gaps between ridges.

Output looks washed out — raise Threshold Min and lower Threshold Max to stretch the contrast and sharpen the ridge lines.

FBM

Balanced fractal octaves — the general-purpose sibling.

Billow Noise

Abs-folded octaves for puffy cloud shapes.