Archive notice: This article was originally published on August 14, 2017. Links and embedded videos are preserved as part of the historical record.
Radeon announced an open source version of ProRender for developers at SIGGRAPH 2017. The ProRender plugins for Maya, 3DS Max, Blender and Solidworks are not affected by this. Developers can, however, can create their own implementations of Radeon ProRender. In addition, Radeon also announced the integration of ProRender into Cinema 4D R19 and Modo.
To the Github project
Further details about the announcement can be found here on the Radeon website and here.