Random
Generate random numbers from a chosen distribution and seed.
What it does
Random draws from whatever you give it. Wire something with rows into Source and it makes one independent draw per row, handing back as many values as the wire has; leave Source empty and it makes a single draw. Mode sets what a draw means: Uniform (a value in a range), Integer (whole numbers), Walk (drifts from its previous value), Pick (one element of the wired array), Shuffle (reorders that array), or Unique (whole numbers with no repeats).
Bias reshapes the distribution. It is a curve you draw: a straight line is flat, bending it crowds values toward one end of the range, and an S-shape crowds them toward the middle.
Every draw is seeded. The same Seed reproduces the same sequence on a given node.
When to use it
A number, colour or vector that changes every frame: flicker, jitter, dice rolls, procedural variation
A different random value for every point, shape or row of something upstream: wire it into Source
Randomness that updates only on an event: wire Trigger and set Timing to On Trigger
A value that wanders rather than jumps: Walk mode with Step Size
Grabbing or reordering elements from an array: Pick or Shuffle
Dealing out values with no repeats — card draws, unique indices: Unique
A repeatable result across re-runs: a fixed Seed
| Parameter | Type | Default | What it does |
|---|---|---|---|
mode | String | "Uniform" | Uniform: flat distribution, shaped by Bias. Integer: whole numbers. Pick: random element from the wired array. Shuffle: random permutation of it. Walk: random step from previous. Unique: no-repeat draw (urn model). One of: Uniform, Integer, Pick, Shuffle, Walk, Unique. |
timing | String | "Every Frame" | Every Frame: new random each cook. On Trigger: new random only when trigger fires, holds value between. One of: Every Frame, On Trigger. |
trigger | Boolean or Number | — | Rising edge generates new random value. Value holds until next trigger. |
threshold | Number | 0.500 | Trigger fires when input crosses above this value |
min | Number | 0 | Minimum output value (inclusive) |
max | Number | 1 | Maximum output value (inclusive for Integer, exclusive for Uniform) |
output_type | String | "Number" | Output value type for a single draw. Vec2/Vec3: each component randomized independently within range. Color: RGB random, A=1. Wire `source` for one Number per row instead. One of: Number, Vec2, Vec3, Color. |
step_size | Number | 1 | Maximum random step per trigger. Value drifts within [min, max]. |
exclude | Number[] or Int[] | — | Array of values to exclude from generation. An excluded value is never emitted; the values that remain stay uniformly likely. |
source | Collection or Number[] or Vec2[] or Vec3[] or Color[] or Int[] | — | What to draw from. Uniform/Integer: one draw per row of this wire (unwired = one draw). Pick: one element of it. Shuffle: a permutation of it. |
seed | Number | 0 | Seed for deterministic random sequence. Same seed = same sequence. |
snap | Number | 0 | Quantize output to multiples of this value. 0 = no snap. 1 = integers. 0.25 = quarter steps. |
bias | Curve | 2D Curve | Shape of the distribution. A straight line is flat/uniform; bend it to crowd draws toward one end, or make an S to crowd them toward the middle. |
Gotchas
Source means two related things, and which one depends on Mode. In Uniform and Integer it is the population: one draw per row, and the result is as long as the wire. In Pick and Shuffle it is the table being drawn from: Pick returns one of its elements, Shuffle returns a reordering of it.
Output Type (Vec2 / Vec3 / Colour) applies to a single draw only, so it disappears once Source is wired — a per-row result is one number per row.
In On Trigger timing the output holds its last value until the Trigger input crosses above Threshold. With nothing wired to Trigger the value never updates. This works with a wired Source too: the whole set of per-row values holds together and re-draws together.
Snap quantises the result to multiples of its value: 0 leaves it continuous, 1 rounds to whole numbers, 0.25 gives quarter steps. It applies to Uniform and Walk.
Max is inclusive for Integer mode and exclusive for Uniform mode. An Integer range of Min 1 / Max 6 gives a six-sided die; a Uniform range of 0–1 never returns 1.0.
Unique deals from a finite urn: the whole numbers between Min and Max. Ask for more rows than the range holds and the extra rows repeat the last value — widen Min/Max to deal more.
Two Random nodes with the same Seed draw independent sequences from each other. The seed guarantees repeatability per node, not a shared sequence across nodes.
Worked example
Add a Random node. Leave Mode on Uniform and set Min/Max for the range required.
Wire a set of points or shapes into Source. The output becomes one value per element instead of a single number — feed it into a size, rotation or colour to vary them all independently.
Bend the Bias curve to change where the values cluster: pull it low and early to crowd them toward Min, or make an S to crowd them toward the middle.
Set Timing to On Trigger and wire a pulse into Trigger to freeze the values between events instead of redrawing every frame.
Switch Mode to Walk and set Step Size to make a single value drift smoothly instead of jumping.