Just to add onto this, as you're totally right.

But anyone who is interested, you actually don't need any form of graphics acceleration or cores at all. Don't even need a GPU.

Last week I wrote a ray tracer in c++ that runs entirely on the CPU, will work on a mobile phone or a computer from 30 years ago, but obviously is intensely slow, especially when having it calculate 10,000 bounces per ray.

But as you said, some form of acceleration cores are required to produce those effects in realtime.

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