Universe

A MetaPost-like approach to running a pen along a path — for Typst 0.15+.
Français · Manual (EN) · Manuel (FR) · Gallery · Changelog

nibart brings the heart of Metafont/MetaPost to Typst: smooth paths described with Hobby’s algorithm (directions, tensions, curls), and pens — circle, ellipse, broad-edged nib, polygon, or a nib that changes width and angle along the stroke — whose exact swept outline is computed for you. Calligraphy, lettering, flourishes, hand-drawn diagrams, technical figures in the MetaPost tradition: all as plain vector shapes.

Gallery of calligraphic paths, ornaments, and decorative drawings

Installation

From Typst Universe there is nothing to install: #import "@preview/nibart:0.3.0" as nib.

Quick start

#import "@preview/nibart:0.3.0" as nib

// a path in MetaPost syntax, a broad-edged pen
#nib.nib-stroke(
  nib.mp-path("(0,0){up}..(25,45)..(60,10)..(95,50)"),
  pen: nib.broadnib(10pt, t: 2.5pt, angle: 35deg),
)

// a nib whose width changes along the stroke, and that follows the path
#nib.nib-stroke(
  nib.mp-path("(0,0)..(30,40)..(60,0)..(90,40)"),
  pen: nib.nibpen(
    (at: 0%, width: 3pt), (at: 50%, width: 14pt, thinness: 40%), (at: 100%, width: 3pt),
    angle: 40deg,
  ),
  fill: rgb("#7a2e0e"),
)

The axes follow MetaPost (y points up, angles are counter-clockwise). Use nib.xxx rather than import "…": *: the package exports generic names (draw, cubic, reverse, pressure…).

Features

  • Path language — mp-path("(0,0){up}..tension 1.5..(40,20)--cycle"): .., --, {dir}, {curl}, tension, controls, cycle; also mp-path-pts, cubic, straight, polyline, cubics, path-join.
  • Hobby’s algorithm, checked against mpost (same control points, max difference < 0.01 pt on 17 test paths).
  • Pens — pencircle, penellipse, broadnib, penpoly, pensquare, penrazor, and nibpen with stops along the arc length and an optional follow-the-tangent mode.
  • Exact outlines — the swept region is computed as real geometry (no stamping), with a union of all overlaps.
  • Calligraphic effects — irregular dashes with jitter, intermittent pressure, layered pieces, outlines, a debug view.
  • Path operations — point-of, direction-of, arclength, arctime, subpath, reverse, closest-time, intersection-times, intersection-point, bounding box, and affine transformations (shifted, scaled, rotated, slanted, reflected, transformed…).
  • Knots and interlace — knot(...): automatic crossings (also within one strand), alternating over/under, “gap” or Celtic “weave” style, links, braids.
  • Calligraphic ornaments — copperplate (pointed pen), prongs (multi-tine nib), delimiter (braces and parentheses between two points).
  • Path surgery — offset (parallel curves), shorten, split-at, remove-intervals, weld, join-smooth, round-corners, frames-along…
  • Figures — mp-fig (like beginfig … endfig) with dots, labels, fills, skeletons and an optional grid; baseline-aware, so figures can be used inline.
Exotic collection of decorative illustrations and intricate patterns Presentation slides featuring calligraphic paths and pen effects
Examples of calligraphic lettering drawn with varied nib shapes Decorative flourishes and ornamental pen strokes

nibart: knots, braces, pointed pen

Trefoil, Olympic and Borromean rings, braids and Celtic interlace; calligraphic braces; a copperplate pen; offsets, rounded corners and frames along a path — examples/nibart.typ (--input lang=en for English captions).

Knots, Celtic interlace, calligraphic braces, and pointed-pen ornaments

The unexpected

A score with tapered slurs, knots that weave over and under (computed with intersection-times), a neon sign, embroidery, a fractal cherry tree, a dry-brush enso, an engraved sphere, guilloché, a map and a hand-drawn sketch — one file, examples/insolite.typ (--input lang=en for English captions).
Dry-brush enso, pink cherry tree, engraved sphere, and guilloché medallion Interlaced knots, a musical score, neon nib sign, and embroidered flower Illustrated island map, shaded contour map, and hand-drawn workflow sketch

The complete sources of these pictures are in examples/ (galerie, exotique, boites, calligraphie, insolite, nibart, demo, chat, ile, ile-chat, podium). In a clone of the repository, compile them with typst compile --root . examples/galerie.typ. The examples that the manual does not show are gathered, with a preview, a description, the functions they use and their build command, in an illustrated gallery generated with sh scripts/build-gallery.sh && make gallery. Most examples are bilingual: add --input lang=en or --input lang=fr.

Documentation

The reference manual (English and French; every function with its parameters table and a detailed example, all executed by the package itself) is in docs/: manual-en.pdf, manual-fr.pdf. Rebuild it with typst compile --root . docs/manual.typ (add --input lang=fr for French).

Limits

  • Not implemented: atleast, &, buildcycle; ... behaves as ...
  • draw returns filled shapes; mp-label content is not part of the automatic bounding box.
  • The geometry lives in a WebAssembly plugin (nibart.wasm); it works with the Typst CLI and packages from Universe.
  • Variable pens, dashes and pressure are slower than fixed pens (see the manual for tuning).

Development

The Rust sources of the plugin are in rust/ in the repository (not part of the published package). make wasm rebuilds nibart.wasm (target wasm32-unknown-unknown), make test runs the tests, make docs rebuilds the manual, make package produces and validates the publishable directory in dist/.

Licence

Author: FERGOUS Abdelhak (@fergousA) · repository: https://github.com/fergousA/nibart.
MIT. Third-party crates: see THIRD-PARTY-NOTICES.md. Inspired by MetaPost (D. Knuth, J. D. Hobby) and by the nibst package (B. Auguie): the calligraphic options reproduce its described behaviour; no code from either project is included.