@sumisonic/bezier-kit-core

Zero-dependency TypeScript cubic-bezier library (geometry layer). Works with both 2D and 3D.

See the repository README for full usage, type hierarchy, non-goals, rendering examples, and comparisons with other libraries.

Installation

pnpm add @sumisonic/bezier-kit-core

Minimal example (2D)

import { createPathInterpolator, fromCatmullRom, type Point2D } from '@sumisonic/bezier-kit-core'

const a = fromCatmullRom<Point2D>([
  { x: 0, y: 0 },
  { x: 100, y: 50 },
  { x: 200, y: 0 },
])
const b = fromCatmullRom<Point2D>([
  { x: 0, y: 0 },
  { x: 100, y: -50 },
  { x: 200, y: 0 },
])

const interp = createPathInterpolator(a, b)
const morphed = interp(0.5) // BezierPath<Point2D>

Switching to 3D is just changing the type parameter to Point3D (mixing 2D and 3D is a compile-time error).

Features

• Path-level: createPathInterpolator / createPathInterpolatorStrict / createPathSplitter / matchSegmentCount
• Arc-length queries: pointAtLength / tangentAtLength
• Segment-level: pointAt / tangentAt / splitSegmentAt / arcLengthTo / segmentLength
• Arc-length index: createArcLengthIndex / arcLengthToParam
• Bounding box: bbox (returns BBox2D or BBox3D depending on input)
• Construction from points: fromCatmullRom / fromPolyline
• Functor: mapPoints (2D ↔ 3D conversion, translation, scale, etc.)
• Math utilities: lerp / clamp / lerpPoint / distance / scan / binarySearchIndex
• Types: Point2D / Point3D / Point, BezierSegment<P>, BezierPath<P>, BBox2D / BBox3D / BBox<P>, ArcLengthIndex<P>, ArcLengthLocation

See the repository README for API details.

License

MIT © sumisonic