Declarative 2D vector graphics for OCaml


Vg is an OCaml module for declarative 2D vector graphics. In Vg,
images are values that denote functions mapping points of the
cartesian plane to colors. The module provides combinators to define
and compose these values.

Renderers for PDF, SVG, Cairo and the HTML canvas are distributed with the
module. An API allows to implement new renderers.

Vg depends only on Gg. The SVG renderer has no dependency, the
PDF renderer depends on Uutf and Otfm, the HTML canvas
renderer depends on js_of_ocaml, the Cairo renderer depends on
cairo2. Vg and its renderers are distributed under the ISC

Home page:


Vg can be installed with opam:

opam install vg                               # SVG renderer only
opam install uutf otfm js_of_ocaml cairo2 vg  # all renderers

If you don't use opam consult the opam file for
build instructions and a complete specification of the dependencies.


The documentation and API reference is generated from the source
interfaces. It can be consulted online or via odig doc vg.

Sample programs and images

If you install Vg with opam sample programs are located in the
directory opam var vg:doc.

A database of sample images can be found in the db directory of the
distribution. An online rendering of the database is available

Sample programs are located in the test directory of the
distribution. They can be built and listed with:

topkg build --tests true && topkg test --list
  • min_pdf.native, minimal example to render an image to a PDF file.

  • min_svg.native, minimal example to render an image to an SVG file.

  • min_htmlc.byte, minimal example to render with the HTML canvas.

  • rsvg.native, renders images of the Vg image database to SVG files.

  • rpdf.native, renders images of the Vg image database to PDF files.

  • rcairo.native, renders images of the Vg image database with Cairo
    to PDF, PNG, PS or SVG files.

  • rhtmlc.html and rhtmlc.byte can be processed with js_of_ocaml,
    the resulting webapp renders images of the Vg image database with
    the HTML canvas, PDF and SVG renderers.

  • vecho.native, like echo(1) but produces a PDF file on stdout, the
    font file can be specified, invoke with -help for options.

  • fglyphs.native, renders a font's glyphs to a PDF file (without using
    Vg's glyph API).

28 May 2020
>= "3.6.0"
>= "0.9.0"
>= "4.03.0"
Reverse Dependencies