Dev:Building On Mac OS X
From Synfig Studio :: Documentation
There is currently no up-to-date build of Synfig for Mac OS X.
There seem to be two ways of building GTK applications for OS X:
Using the native GTK port
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MangoFusion managed to build using the GTK port. Apparently the fileselectors don't work, and the menus don't work properly, but he was able to make this screenshot: [1]
Using X11
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