operakala said:
I understand that ray tracing can be real-time, as in games, and, so to speak,
It's generally referred to as offline rendering when you're (pre)rendering non-real-time approach and real time/interactive rendering when rendering with immediate output once frame is finished.
operakala said:
Now, if I want to explore ray tracing, do I necessary need the RTX type graphics card? For the real-time I probably do, but what of
It… depends.
If you want to use ray tracing apis (like DirectX Ray Tracing or Vulkan Ray Tracing - both of which have their pluses and minuses, along with specific limitations) - you will need a graphics card supporting those. For that I believe you need any Radeon 6xxx series and higher or Nvidia GeForce 10xx series or newer.
If you don't want to use ray tracing apis (there are reasons not to), you can perform ray tracing on CPU or in compute programs on GPU (through any available api - Direct3D, OpenGL, Vulkan, OpenCL, CUDA would be the most known ones). For this I can point you to excellent series by Jacco Bikker - https://jacco.ompf2.com/2022/04/13/how-to-build-a-bvh-part-1-basics/
Notes:
I personally had my share of writing interactive ray tracers for quite some time - but I haven't ventured too deep into DirectX Ray Tracing or Vulkan Ray Tracing. It's still on my todo list as I'm curious how faster/slower it is compared to my solution.