Yes at the moment it’s a very “Microsoft/Nvidia” initiative meaning it’s PC only. AMD cards will not have hardware acceleration yet, but they say they have superior compute performance out of the box (=hence cryptominers. craze…), and it seems logical to think they will want to play catch up with Nvidia (especially considering the direct benefit to Prorender).
I think this is similar to what happened with PhysX technology : at first it was all on the CPU, then the Ageia PhysX guys made some dedicated hardware that was interesting but nobody really bought, until Nvidia took it all and added it to their Geforce cards, at which point it became a commodity.
Sadly though, unless an OpenGL equivalent (pushed/financed by whom? AMD? Does Apple even care?) surfaces, Mac users will most likely not benefit from it in the short term (not that I use Mac myself, but this means a big chunk of C4D users will not be able to use it, hence no DXR/RTX viewport or renderer in the foreseeable future from Maxon).
This being said, if next year or so, most of the new cards have hardware raytracing acceleration capabilities, third party vendors like Redshift, Octane or even Cycles will certainly jump on board and we might see some significant speed boosts (it’s already impressive enough with Octane 4 without dedicated raytracing HW, let’s see what it will become next…)
Edit : Added AMD’s own initiative :
[quote=]AMD is announcing Radeon ProRender support for real-time GPU acceleration of ray tracing techniques mixed with traditional rasterization based rendering. This new process fuses the speed of rasterization with the physically-based realism that users of Radeon ProRender expect for their workflows. At a high level, the process achieves these results by using rasterization to draw basic structures and surfaces before a ray tracing process is used to compute advanced light-effects like reflections, shadows and transparency. The flexibility of the process allows users to decide when these advanced light effects are actually necessary and add noticeable new dimensions of realism to their renders.[/quote]](https://gpuopen.com/announcing-real-time-ray-tracing/)