Utility

Plumbing: pick a channel, switch a branch on or off.

2 ops: pick-channel, switch.

Ops with no demo image below produce no visible result on their own — they feed other nodes rather than paint.

pick-channel

Extract a single channel of an RGBA raster as a [0, 1] ScalarField. RGB channels are read in non-premultiplied space; luminance is Rec. 601 luma over the non-premultiplied colour. Bridges the raster pipeline into scalar-field ops (map-range, threshold, color-ramp).

Field	Type	Required	Description
channel	r | g | b | a | luminance	no	—
input	@node	yes	Reference to another node (@name).

switch

Pick a or b based on select (default a). Both inputs accept any port kind. A literal select is resolved when the graph is built, and the output mirrors the chosen input’s kind — so the two inputs may be different kinds. A $param or @node select is read per render instead, which requires both inputs to be the same kind.

Field	Type	Required	Description
a	@node	yes	Reference to another node (@name).
b	@node	yes	Reference to another node (@name).
select	a | b | boolean | integer (0…1) | $param | @node	no	—