[macOS] ImGui fails to render in e63a36d31f06de4c71ffed3ff505c8b5b93e51d8

[fiserj]

System Info

• macOS Ventura 13.5.2
• Xcode 15.0.1

Issue

After updating to e63a36d31f06de4c71ffed3ff505c8b5b93e51d8, the UI window doesn't render.

Building from previous commit (16c9bb188713c908240939992e239264ff2018e6) works:

Steps to Reproduce

Just checkout latest commit (e63a36d31f06de4c71ffed3ff505c8b5b93e51d8) and build with CMake, i.e.:

git clone https://github.com/floooh/cimgui-sokol-starterkit.git
cd cimgui-sokol-starterkit
mkdir build && cd build
cmake ..
cmake --build .
./demo

Note that building via Xcode (i.e., configuring with-G"Xcode") makes no difference.

[fiserj]

I haven't yet had a chance to look into it more, but quick bisecting suggests https://github.com/floooh/sokol/commit/99986cccaaec2ebc21b79e680b543eeb91d60f03 is the culprit. I could compile with the latest ImGui up until that commit.

Edit: Hah, looking at that commit, I don't see why that would be an issue. Will need to take a better look later.

Edit 2: I can confirm that last commit in master that works for me is https://github.com/floooh/sokol/commits/8d5d9929cc559cc6ec087fb621bfbe58c9ccc028. Looking at github's history log, the commit I posted above seems to be going just after this one, but when I check https://github.com/floooh/sokol/commit/99986cccaaec2ebc21b79e680b543eeb91d60f03 history, it's parent is entirely different commit.

[floooh]

Are you on an Intel Mac?

I'm on an M1 Mac with macOS 14.0 and everything works here. I can check later on my Intel Mac. Need to deal with another recent regression in GL first.

[fiserj]

Yes, I am.

[floooh]

That last commit that works for you was around the time when the image/sampler split happened, but let me check on my Intel Mac later...

[fiserj]

Thanks! And yes, manually diffing those two commits listed above points to the split you mention.

[floooh]

Bad news, it's working here. But I'm on a different macOS version (latest Big Sur, the last macOS supported on my mid-2014 MBP).

When running in Xcode, do you see any Metal validation layer errors in the bottom right output panel?

I think this scary looking piece of code is also from around that time:

https://github.com/floooh/sokol/blob/227df3a3f9623fda949011d0e88c4f40c1855fbe/sokol_gfx.h#L11458-L11475

...and there was indeed a problem with Intel Macs regarding textures.

Can you try changing the sg_setup call like this and check if it changes anything?

    sg_setup(&(sg_desc){
        .mtl_force_managed_storage_mode = true,
        .context = sapp_sgcontext(),
        .logger.func = slog_func,
    });

(I'll log off for today but will be back tomorrow evening)

[floooh]

...in general I suspect the culprit might be any of the if (@available( checks in sokol_gfx.h.

IIRC I added those with the image/sampler split to better support optional Metal features on macOS and iOS.

And maybe some of those checks do the wrong thing in the "gap" between Big Sur and Sonoma....

[fiserj]

Hm, indeed, on my older Intel-based Mac that also runs Big Sur, everything renders fine.

I don't see any Metal validation layer error (the settings is on), and the change in sg_setup descriptor also didn't make any change :/ (it looks like _sg.mtl.use_shared_storage_mode has been set false all along).

I'll try to find some more time in the rest of the week to poke around the other API-availability checks.