Split / Combine
Break a per-element attribute into named scalar channels (hue/sat/lum, x/y/z) or build one from them, on an RGB, HSV, HSL, or LAB colour basis. Channel rewires a colour's RGBA in place; Convert changes a single value's space.
What it does
Split / Combine moves data between one compound attribute, such as a colour or a position, and a set of named scalar channels. Split reads an attribute, Cd, P, or any other colour or vector attribute on the incoming collection, and writes it out as separate named columns: hue/sat/lum for an HSL basis, x/y/z for Cartesian. Combine reads those named channel columns back off the collection and packs them into one compound attribute.
Basis decides both the channel names and whether a colour conversion happens. RGB, HSV, HSL and LAB convert colour on the way in or out; Cartesian reads or writes the raw x/y/z lanes with no conversion. Split and Combine share the same basis logic, so splitting and combining the same attribute with the same basis round-trips it.
When to use it
Grading or keying off a colour by hue, saturation or lightness: Split with an HSL or HSV basis, then work with
hue/sat/lumas ordinary scalar attributesPacking separately computed
x/y/zorhue/sat/lumcolumns back into one attribute such asCdorP: CombineIsolating one lane of a position or vector attribute, for example driving something from only the
xofP: Split with a Cartesian basis
| Parameter | Type | Default |
|---|---|---|
collection_in | OneOf([Collection]) | — |
direction | String | "Split" |
source | String | "Cd" |
target | String | "Cd" |
basis | String | "HSL" |
strength | Number | 1 |
Gotchas
Switching Basis changes the channel names Split writes and the names Combine reads. Downstream nodes referencing hue/sat/lum are not renamed automatically.
Split and Combine both need the source attribute or the channel columns to already exist on the collection. Where the attribute named in Source (Split) or the channel columns Combine expects are absent, the collection passes through unchanged rather than being guessed at or fabricated.
Colour bases (RGB/HSV/HSL/LAB) always rebuild a 4-channel colour on Combine with alpha set to 1. Split does not carry alpha out as a channel, so an alpha held before a Split/Combine round-trip does not come back through this node.
Worked example
Add a Split / Combine node and wire a collection with a
Cdcolour attribute into Collection In.Leave Direction on Split, Source on
Cd, and set Basis to HSL. The node now writeshue,satandlumscalar columns onto every element.Adjust
satorlumdownstream, for example with an Expression or Math node, to grade the colour.Add a second Split / Combine node, set Direction to Combine, Target to
Cd, and Basis to HSL to pack the edited channels back into a colour.