[w-m]

For some reason the GUI is not showing up for me in 3DGS.cpp. (I checked out the repo, made a build folder and built with Ninja, then launched ./apps/viewer/vulkan_splatting_viewer).

I still have a VulkanSplatting build from this Wednesday though. In VulkanSplatting, when looking at the Lego scene from above with the default window size, I'm getting just below 1 ms for the sorting kernel and just above 1 ms for "render", everything else is too small in the graph to register. But it only displays at a handful of fps, so it seems quite some time goes unaccounted for.

Maybe spinning up Instruments could give some more insights into what's happening? I tried `cmake -G Xcode` to have that setup easily, but the Xcode CMake generation fails with

    CMake Error in src/shaders/CMakeLists.txt:
      The custom command generating
    
        3DGS.cpp/build-xcode/shaders/shaders.h
    
      is attached to multiple targets:
    
        shaders
        xcode_shaders
    
      but none of these is a common dependency of the other(s).  This is not
      allowed by the Xcode "new build system".

[0x02A]

Yeah, I gave it a try and timings seems to be very wrong. I'll fix that soon.

I haven't tried benchmarking SPIR-V shaders on macOS. Since they're translated into Metal shaders anyways, it should be possible theoretically.

Also, for the command line viewer in the new version, I've only tested make or ninja. I'll take a look at xcode when I get a chance.

Update: I just gave Instruments a try and it seems like the Metal compiler grouped all of the compute and copy operations together and just left the timestamp operations to run back to back. Since MoltenVK isn't a conformant implementation, I'm guessing the synchronization dependencies weren't respected.

However, I'm still getting 200ms frame times on the Garden scene at 4K with M1 Pro. The lego scene shouldn't be too bad even on an Intel Mackbook.