The SIF output extension is now part of Inkscape's development repository. It adds a ".sif" option to Inkscape's "Save As" Dialog.
Please help test it to make sure that the version that ships in Inkscape 0.49 runs smoothly.
For stable versions of Inkscape, you can download the code and read the installation instructions on github:
Download (.zip) https://github.com/nikitakit/svg2sif/zipball/stableDownload (.tar.gz) https://github.com/nikitakit/svg2sif/tarball/stableGithub page / Installation Instructions: https://github.com/nikitakit/svg2sif(If you're using Inkscape nightly builds or building Inkscape trunk yourself the extension should be installed automatically.)
Inkscape writes out SIF files within the following constraints:
- It's designed to work with Inkscape-created SVG files. SVG files loaded from other programs may not work as well
- Blurs don't transfer over one-to-one. The resulting SIF file may need to be hand-edited to make the blurs stronger or weaker
- SVG filters are ignored. They do not port easily to Synfig, and some can't be converted at all.
- Radial gradients with focus not at the center are not allowed. The Synfig renderer does not support them.
- Dashed outlines, markers, and patterns are ignored. If you need them, post a feature request.
All SVG files falling within these constraints are fair game -- if they don't work, leave a comment here and I'll try to fix the problem.
If everything works as expected, please post a reply as well. I would like to know how many people have tested it and what setups they use.