appleseed is a modern, open source, physically-based rendering engine designed to produce photorealistic images, animations and visual effects. It's been used on TV documentaries and commercials, and it's been integrated in various packages, among them Autodesk 3ds Max [1] and Image Engine's Gaffer [2]. We've also made a short film with it, "Fetch": <a href="https://vimeo.com/92172277" rel="nofollow">https://vimeo.com/92172277</a><p>This month we're planning on starting the volume rendering subsystem (<a href="https://github.com/appleseedhq/appleseed/projects/1" rel="nofollow">https://github.com/appleseedhq/appleseed/projects/1</a>) and, if time allows, investigate switching to Intel's Embree ray tracing kernels [3].<p>The code is written in C++ and we have a Python 2/3 API. There is work for everyone: pure rendering (a good understanding of rendering concepts and related maths will help), user interface (Qt), samples (Python), system programming, hardcore optimization...<p>It all seems rather technical, but don't be afraid, we're a small but welcoming community and everyone's happy to help!<p>appleseed is MIT-licensed.<p>Home: <a href="http://appleseedhq.net/" rel="nofollow">http://appleseedhq.net/</a><p>GitHub: <a href="https://github.com/appleseedhq/appleseed" rel="nofollow">https://github.com/appleseedhq/appleseed</a><p>Vimeo: <a href="https://vimeo.com/appleseedhq" rel="nofollow">https://vimeo.com/appleseedhq</a><p>[1] <a href="https://github.com/appleseedhq/appleseed-max" rel="nofollow">https://github.com/appleseedhq/appleseed-max</a><p>[2] <a href="http://www.gafferhq.org/" rel="nofollow">http://www.gafferhq.org/</a><p>[3] <a href="https://embree.github.io/" rel="nofollow">https://embree.github.io/</a>