OpenCL GPGPU Brep Raytracing
While there is existing ANSI C/C++ code for https://en.wikipedia.org/wiki/Boundary_representation in BRL-CAD it is not GPU parallel. Porting it to the GPU with OpenCL should be rather complex because much of this code is written in object oriented C++.
So the first task you should make to start an OpenCL port of this is to make a simplified version of the code which uses strict ANSI C. Alternative you can also look into incorporating SYCL for the Brep code. SYCL is a GPU parallel language based on C++ which should be possible to interface with OpenCL.