• Public
  • Public/Protected
  • All



npm version npm downloads Twitter Follow

This project is part of the @thi.ng/umbrella monorepo.


nD cubic & quadratic curve analysis, conversion, interpolation, splitting.

Current implementations partially based on toxiclibs (Java) and Clojure version of thi.ng/geom.


STABLE - used in production


yarn add @thi.ng/geom-splines

Package sizes (gzipped): ESM: 2.2KB / CJS: 2.3KB / UMD: 2.3KB


Usage examples

Several demos in this repo's /examples directory are using this package.

A selection:


Live demo | Source


Generated API docs

Cubic curve conversion from polygons & polylines

Currently, there're two ways to convert a polygon/polyline into a sequence of cubic curve segments. Both modes support customizable curve tightness.

Furthermore, both conversion modes can be instructed to use uniformly scaled control point tangents: In uniform mode, the tangents have a uniform, user defined length, resulting in equidistant control points for each poly vertex. In non-uniform mode, each tangent is scaled by the length of its parent poly edge.

Poly vertices as control points

In this mode the curve always goes through the midpoints each polygon edge, with the original polygon vertices being used to compute control points.

Proportional tangent scale Uniform tangent scale

Poly vertices as break points

In this mode the curve always goes through the original polygon vertices and additional control points are created via symmetric tangents at each poly vertex. The tangents themselves are computed via the bisector of each vertex corner, taking into the convexity of each poly vertex.

Proportional tangent scale Uniform tangent scale


Karsten Schmidt


© 2016 - 2020 Karsten Schmidt // Apache Software License 2.0

Generated using TypeDoc