[mateuszf]

I'm wondering - heard that PS3 architecture is so complex, and PS4 is back to x86 - so what is it that makes PS4 emulators so hard to implement?

Surely nowadays hardware such as 7000 ryzen series and 4090 gpus are leaps and bounds above PS4 hardware.

[dagmx]

The PS4 has its own graphics API called GNM and GNMx that would need to be reverse engineered and ported.

It also has shared memory between the CPU and GPU that are harder to do with a discrete GPU. See how much work Dolphin has to do with the various direct write memory tricks for the GameCube. Now imagine that kind of trickery on a bigger scale for the PS4.

[pushedx]

Having very briefly looked into this problem a few years ago, my impression of the primary challenge was that of re-implementing a large OS API surface in a non-infringing way.

[mateuszf]

Looking how some emulators just ask users to copy firmware / software / keys from their real consoles - couldn't the same thing be done and only the hardware layer be emulated?