color-kitnext

API

@pbroom/color-kit/hct

Material HCT conversion, gamut limits and tonal helpers.

6 exports3 values3 types

@pbroom/color-kit/hct answers gamut questions in Material Design's HCT space: CAM16 hue and chroma with L* tone, the space Material's tonal palettes are built in. The root @pbroom/color-kit entry re-exports the same functions.

Domains

  • Chroma limits. maxHctChromaAtTone returns the largest chroma sRGB can realize at a hue and tone.
  • Hue peaks. maxHctChromaForHue returns the peak chroma of a hue and the tone where it occurs; maxHctPeakToneForHue returns just the tone. Both interpolate a cached per-hue lookup table by default (method: 'lut') and search tone directly with method: 'direct'.

Conversion lives in the root entry: toHct and fromHct convert between Color and { h, c, t, alpha }. fromHct uses Material's solver, which reduces chroma to fit sRGB, so its results are always in sRGB and quantized to 8 bits.

tones.ts
import { maxHctChromaAtTone, maxHctChromaForHue } from '@pbroom/color-kit/hct';

maxHctChromaForHue(250); // → { c: ≈ 61.71, t: ≈ 64.22 }
maxHctChromaAtTone(250, 90); // → ≈ 21.00, light tones hold little chroma

Use these limits to build HCT tonal ramps that ask only for chroma sRGB can deliver, instead of letting fromHct reduce it silently.

HCT