scale-colour-distiller

Continuous ColorBrewer colour scale.

Looks up a Brewer palette by name and interpolates linearly across its stops as a continuous ramp. direction flips the palette: 1 keeps the canonical order, -1 reverses it.

Usage

scale-colour-distiller(
  palette,
  direction,
  name,
  limits,
  oob,
  breaks,
  labels,
)

Parameters

Parameter	Default	Description
palette		ColorBrewer palette name (sequential or diverging works best).
direction		1 for canonical order, -1 for reversed.
name		Legend title. Overrides any name set via labels when both are present.
limits		Pair (lo, hi) clipping the trained domain, or none.
oob		Out-of-range policy: "drop" (default) removes rows whose value falls outside limits; "squish" clamps continuous values to the nearest endpoint.
breaks		Array of break values for the legend, or auto.
labels		Array of legend labels aligned with breaks, or auto.

Returns

Scale object consumed by plot.

Examples

Spectral palette interpolated as a continuous ramp.

#let d = range(0, 12).map(i => (x: i, y: i, z: i * 0.5))
#plot(
  data: d,
  mapping: aes(x: "x", y: "y", colour: "z"),
  layers: (geom-point(size: 3pt),),
  scales: (scale-colour-distiller(palette: "Spectral"),),
  width: 10cm,
  height: 6cm,
)

Set direction: -1 to reverse the palette so high values map to the canonical low end.

#let d = range(0, 12).map(i => (x: i, y: i, z: i * 0.5))
#plot(
  data: d,
  mapping: aes(x: "x", y: "y", colour: "z"),
  layers: (geom-point(size: 3pt),),
  scales: (scale-colour-distiller(palette: "Blues", direction: -1),),
  width: 10cm,
  height: 6cm,
)

See also

scale-fill-distiller, scale-colour-gradientn, scale-colour-brewer.