SideFX simplified the usage of OpenCL inside Houdini and offers new examples along with another video course.
Luca Pataracchia / SideFX:
https://www.sidefx.com/tutorials/opencl-cop-for-vex-users/
Jeff Lait / SideFX:
https://www.sidefx.com/tutorials/houdini-165-masterclass-opencl/