Demon's Souls reaches 40-50 FPS on private PS5 emulator with accurate graphics
Few projects in the software world have experienced such rapid evolution as PlayStation 5 emulation. A few hours ago, a video popped up of Demon's Souls Remake running at 40-50 FPS, seemingly with accurate graphics. Coincidentally or not, only scant months after Sony ditched physical releases of games - an announcement that landed as well as the Hindenburg - progress on KyTyPS5, SharpEmu, and AnyPS5 has gone into overdrive.
The video above is short and only shows a few sections of the game, but it's an impressive watch. Even acknowledging that the hardware specs displayed comprise an RTX 5090 and a Core i9-14900K, having a game working this well, at least graphically, only a month after "barely works" was a landmark is nothing short of staggering.
To wit, KyTyPS5 was running Demon's Souls Remake with 1-2 FPS on actual gameplay three weeks ago, and struggling to reach 30 FPS a fortnight past. The same emulator has been shown partially running GTA V before at 40-60 FPS, but that's an older title that presumably isn't as demanding as Demon's Souls.
The fact that the PlayStation 5's architecture is so similar to a standard PC apart from unified memory is a big reason why progress has been so speedy. As it stands, the major roadblocks aren't emulating a CPU or a GPU, but rather writing compatibility layers for the console's operating system and drivers, including but not limited to converting native graphics shaders to Vulkan's SPIR-V language.
Given the demo video's lack of stuttering, it's a reasonable assumption that the captured video was done after an initial run to avoid shader recompilation hitches. This particular aspect of emulation has always been a constant thorn in developers' side, as it's exceedingly difficult to predict which shaders a game will need before they're actually used.
The current best approach is to asynchronously compile and collect shaders from gamers' playthroughs and build a community database for preloading. This concept was popularized by RPCS3 around 2018, with a small team and limited to no budget.
Although Nvidia and AMD drivers have cached shaders in limited fashion for a long while, RPCS3's effort appeared seven years before Nvidia and Microsoft, with their gigantic piles of money, bothered to try and fix this issue properly with their Auto Shader Compilation and Advanced Shader Delivery, respectively.