Hey, I’m new to Unreal Engine Forums but not new to Unreal Engine itself. I read through the website’s tutorials ~2 years ago and played with the editor a little. I was really excited when seeing UE5 for the first time, but suspicious when they only mentioned Nanite working on AMD/NVIDIA. I’m really skilled in the Metal API (>1000 hours of experience), and I would be interested in helping out. It seems the Reddit thread was legit, but this was not emphasized properly. Nanite has been run on macOS and iOS, but its performance may be poor. We did not get source code, but we may have enough information to reproduce what happened.
At the WWDC, Apple released Metal 3. The new Metal Shading Language specification includes 64-bit atomics, including atomic_ulong. Earlier in this thread, someone said the lack of that feature was blocking Nanite. I can confirm that feature did not exist, as up to Metal 2.3 (maybe 2.4), the largest atomic size was 32-bit. I don’t know how 64-bit got enabled in Metal 3 (either a hidden hardware feature or emulation), but it doesn’t matter.
Epic might not really want to help Apple users because of their feud and ongoing lawsuit with Apple. If you guys help me out, give me enough time, I see no reason why we can’t bring full-fledged Nanite to macOS. I’m very experienced with Git/GitHub, MSL, C programming, forum posting, and most of all: bypassing artificial restrictions on technology. Perhaps I should ping @gladhu who made the Reddit thread, but also posted on UE forums.