/svg2cairo

SVG to Cairo code converter.

Primary LanguageLua

SVG to cairo code converter

This project converts SVG files to the equivalent cairo source code. After this conversion, you don't need any SVG rendering library to display the content of the file. cairo and the generated source code is everything you need.

Why?

With librsvg, there exists an open-source library that can render SVGs using cairo. However, this library has some bulky dependencies, e.g., GLib. This complicates the distribution of programs using this library.

This converter can replace librsvg at least in thoses cases, where the SVGs are available at compile-time.

How?

1. SVG to cairo XML converter

The first step is to convert the SVG into an XML file describing the cairo drawing commands. This is implemented in svg2cairoxml.c using librsvg and cairo's XML surface that was introduced in cairo 1.10.

2. cairo XML to cairo code converter

Next, we can convert the generated XML file to source code. This is done using a Lua script that parses and processes the XML file.

Download & Usage

Windows

Windows binaries are available by clicking on the download button above. The zip archive contains:

svg2cairoxml.exe       // SVG to cairo XML converter
cairoxml2cairo.lua     // cairo XML to source code converter (Lua script)
lua.exe                // Lua interpreter
formats/               // directory with supported source code exporters (Lua scripts)
tests/                 // sample code (see below)
README.html            // this file in HTML format
and all necessary DLLs

The easiest way to convert SVG files is by using the command line:

> svg2cairoxml.exe svg-file xml-file
> lua.exe cairoxml2cairo.lua [-f format] xml-file source-file

The available formats are described below.

Linux

On Linux, you have to compile svg2cairoxml.c yourself (see below). Additionally, the Lua interpreter is required. The usage is aquivalent to the one on Windows:

$ ./svg2cairoxml svg-file xml-file
$ lua cairoxml2cairo.lua [-f format] xml-file source-file

The available formats are described below.

Output Formats

Currently, format can be one of lua-oocairo, c, and scrupp.

lua-oocairo

Creates a Lua file for use with oocairo (manual), a cairo binding for Lua.

Loading the generated file with require() or dofile() returns a table that contains 3 fields:

  1. width contains the default width of the graphic.
  2. height contains the default height of the graphic.
  3. render is a function that takes a cairo context as argument and renders the graphic using that context.

The default size of the vector image (defined by width and height) can be changed by calling cr:scale(sx, sy) before calling render.

c

Produces C source code. The generated file defines 3 functions:

  1. int cairo_code_BASENAME_get_width() returns the default width of the graphic.
  2. int cairo_code_BASENAME_get_height() returns the default height of the graphic.
  3. void cairo_code_BASENAME_render(cairo_t *cr) renders the image using the provided cairo context.

The default size of the vector image (defined by its width and height) can by changed by calling cairo_scale(cairo_t *cr, double sx, double sy) before calling the render function.

BASENAME is replaced by the name of the source XML file without suffix (e.g., the basename of symbol.xml is symbol).

scrupp

Generates a slua file. If opened with Scrupp, the vector graphic is displayed in a window.

Tests

The tests directory contains sample source code that shows how to load images defined by c code or lua files.

Building

To compile svg2cairoxml.c, librsvg and cairo (1.10 or later) with XML surface support are required.

In the cairo library, rendering to an XML surface is not possible by default. Therefore, --enable-xml=yes has to be passed to configure when compiling cairo.

Windows

The Windows binaries were created on Arch Linux using MinGW compiled for Linux. Most required mingw32 libraries were installed from the excellent Arch User Repository (AUR).

Linux

On Linux, the cairo library has to be compiled manually (pass --enable-xml=yes to configure). You should be able to install all other required libraries with the package manager of your distribution.

Finally, see the Makefile for details on how to compile svg2cairoxml.c.

An alternative to the manual compilation of cairo is the usage of wine with the provided Windows binaries.

TODO

  • remove redundancy, e.g., no more multiple definitions of the same path

License

This software is licensed under the MIT license.
© 2010 Andreas Krinke <andreas.krinke@gmx.de>.