Open-source technology and Hollywood
Big Hollywood visual effects and animation companies often write their own proprietary 3D software. But that doesn’t mean they don’t use open-source technology.
Industrial Light & Magic led the way by opensourcing OpenEXR ( http://openexr.com) in 2003, its proprietary file format for HDR images, now familiar to most photographers.
Sony Pictures Imageworks followed suit with a whole set of open-source technologies ( http://opensource.imageworks.com), including Alembic, now the industry’s standard format in which to transfer complex 3D geometry between software packages.
Disney has also got in on the act with Ptex ( http://ptex.us), which controls the way in which the 2D texture maps that determine the local colour of a 3D model are mapped onto its surface, while DreamWorks has released OpenVDB ( http://openvdb.org), used for volumetric effects like clouds. You can see it in action in the still from HowtoTrainYourDragon 2 ( above).
The big studios open-source their technologies to ensure that there are standard formats in which data can be exchanged when companies have to collaborate on a movie, as is often the case in visual effects – but the benefits are felt by everyone, since they quickly become incorporated into off-the-shelf software.
Blender itself uses several of these code libraries: the most recent release, Blender2.76, incorporates OpenSubdiv, Pixar’s technology for “high-performance subdivision surface evaluation”. (Among other things, it enables animators to preview the movements of their characters more accurately in real time.)
The work seems to have found favour at Pixar, which even switched OpenSubdiv from a Microsoft Public Licence to an Apache Licence so Blender could make use of its technology.