OCaml interface to Cairo

This is an OCaml binding for the
Cairo library, a 2D graphics library
with support for multiple output devices.

You can read the API of
Cairo,
Cairo_gtk,
and
Cairo_pango
online.

Prerequisites

You need the development files of Cairo (see the
conf-cairo
package)
and the OCaml package
lablgtk2 (in the OPAM package
lablgtk).

Compilation & Installation

The easier way to install this library — once the prerequisites are set
up — is to use opam:

opam install cairo2

If you would like to compile from the sources, install Dune

opam install dune

and do:

dune build @install

or just make. You can then install it with:

dune install

Examples

You can read a version of the
Cairo tutorial using
this module. The code of this tutorial is available in the
examples/ directory. To compile it, just do

dune build @examples

All the examples below are available (with some comments) by clicking
on images in the tutorial.

Basic examples

• stroke.ml shows how to draw (stroke) a simple
  rectangle on a PNG surface.

• stroke.ml shows how to fill a simple
  rectangle on a PNG surface.

• showtext.ml illustrates how to select a font
  and draw some text on a PNG surface.

• paint.ml shows how to paint the current source
  everywhere within the current clip region.

• mask.ml shows how to apply a radial transparency
  mask on top of a linear gradient.

• setsourcergba.ml produces

• setsourcegradient.ml shows how to use
  radial and linear patterns. It generates:

• path_close.ml shows how to draw a closed
  path. It produces the PNG:

• textextents.ml displays graphically the various
  dimensions one can request about text. It generates the PNG:

• text_extents.ml exemplifies drawing
  consecutive UTF-8 strings in a PDF file. Some helping lines are
  also added to show the text extents.

• tips_ellipse.ml shows the action of
  dilation on the line width and how to properly draw ellipses.
  It generates the PNG:

• tips_letter.ml illustrates the wrong way
  of centering characters based on their individual extents:

  Instead, one should combine them with the font extents as shown in
  tips_font.ml to have:

Examples generating the images of the tutorial

• diagram.ml draw the images of the section
  Cairo's Drawing Model:

  
  
  
  
  
  
  
  

• draw.ml generates the various images in
  Drawing with Cairo, namely: