In January 2017 we have posted a bounty to integrate MyPaint brushes in OpenToonz. Thanks to support of many community members, the bounty reached its goal and our hired developer Ivan Mahonin started to work on implementing that feature.
Actually, he is already got first working version. See screenshots below and source code here.
Right now Ivan is preparing AppImage builds, so our Linux users will be able to test this feature and help hunting issues. Stay tuned for our news!
P.S. By the way, a few weeks ago Opensource.com website published an article about our work on OpenToonz and Synfig. It really worths to read, if you haven’t yet!
— Open Source Way (@opensourceway) February 7, 2017