Both 1 and 2. I haven’t done much with 3 as OpenCL is effectively a dead api at this point. 1 was definitely a lot easier to work with than 2. CUDA is easier t

Both 1 and 2. I haven’t done much with 3 as OpenCL is effectively a dead api at this point. 1 was definitely a lot easier to work with than 2. CUDA is easier than both but I don’t think I hit anything I could do in CUDA that I couldn’t do in OpenCL, though CUDA of course had a larger ecosystem of existing libraries.