ShadPS4 – PlayStation 4 emulator

Original Article ↗ Hacker News Discussion ↗

Project overview & excitement

  • Thread is broadly enthusiastic about shadPS4 as a milestone for PS4 emulation, especially given Sony’s lack of a portable PS4 option and weak official backwards compatibility.
  • Many see it as proof of how far hobbyist emulation can go without direct financial incentives.

PS4 architecture vs PCs / other consoles

  • Several comments stress PS4 is x86 with a FreeBSD‑based OS and an AMD APU, making CPU-side emulation closer to running a “PC in a box.”
  • Others highlight important differences: custom graphics APIs (Gnm/Gnmx), unified GDDR memory, console-specific GPU behavior, extra instructions, and PS4/PS5 custom hardware (e.g., decompression, storage).
  • PS3 is widely regarded as much harder (Cell CPU translation, LLVM JIT), while PS5 is said to be quite different from PS4 despite both being x86.

Emulator type: compatibility layer vs hardware emulation

  • Multiple posts describe most PS4 “emulators” as more like Wine: reimplement PS4 user-mode libraries, map syscalls, and translate PS4 shaders to SPIR‑V or similar.
  • There is disagreement over labeling: some call shadPS4 an emulator, others insist it and similar projects are fundamentally compatibility layers, with only low‑level projects that virtualize PS4 hardware being “true emulators.”
  • Shader translation is emphasized as a major job, since consoles ship precompiled shaders.

Performance expectations (PC & Steam Deck)

  • Some are pessimistic about Steam Deck running “desired” PS4 titles at good FPS; others argue PS4 emulation should be far lighter than PS3 and will improve with time and hardware generations.
  • On high‑end GPUs (e.g., RTX 4090), Bloodborne already hits very high FPS, though with incomplete/broken shading. One side expects 100+ FPS on mid‑tier PCs once matured; others caution performance will drop as accuracy improves.

Bloodborne and game preservation

  • Bloodborne progress is a central hype driver: first character screen, then in‑game, now very high FPS in limited demos.
  • Many express frustration that Sony has never released a 60fps/PC/remastered version, and see emulation as the only realistic path.
  • Discussion touches on fan 60fps patches on hacked PS4/PS5 hardware and broader dissatisfaction with remasters vs faithful ports.

Learning emulation & resources

  • Commenters recommend starting with very simple systems (CHIP‑8, Game Boy, NES) and share guides, books, and video series.
  • High‑level explanation: emulate CPU, memory, I/O, and hardware mappings, or alternatively emulate system APIs and possibly JIT‑translate instructions.

Legality & “too soon” concern

  • One comment claims PS4 is “too current” and predicts shutdown; others counter that emulators themselves are typically legal, with only game/BIOS distribution being the main legal issue.