title: How to choose OpenCL implementation with CMake?
body: <p>I have a Windows OpenCL application that uses some of the AMD extensions. Additionally, my application has some optional CUDA components. When building the visual studio solution with CMake, the FindOpenCL module picks the Nvidia OpenCL implementation instead of AMD's. Is there an easy way to make CMake use the AMD version?</p>
  
  <p>I tried commenting the Nvidia sections in the FindOpenCL module code, but that did not work. Is there some registry setting I can modify? I installed CUDA after installing AMD's SDK. Would the installation order make a difference?</p>