MAME BGFX - metal (Mac API) crashes since MAME 0.177 ever since

[estefan3112]

Hi, I have been following the BGFX development in MAME since its introduction into the official builds, and it just rocks in MAME!

However, since version 0.177, the bgfx-metal shader crashes on every Mac I tried. In my blog for MAME on Macs, I have documented the regression here:
https://mameonmacs.blogspot.co.at/2016/09/mame-0177-first-impressions.html

The other bgfx shaders are not affected, so I have been constantly using bgfx-opengl without any troubles.

On Macs you should be able to reproduce the error with any game and any frontend, or just via the command line, e.g.
./mame64 -video bgfx -str 60 -noafs -bgfx_screen_chains crt-geom-deluxe -bgfx_backend metal -artcrop -noreadconfig -nosleep -nothrottle elevator
Comment: With the crt-geom-deluxe shader, the game runs in black screen, and when pressing Esc, MAME quits with "CoreAnimation: warning, deleted thread with uncommitted CATransaction; set CA_DEBUG_TRANSACTIONS=1 in environment to log backtraces."

./mame64 -video bgfx -str 60 -noafs -bgfx_screen_chains hlsl -bgfx_backend metal -artcrop -noreadconfig -nosleep -nothrottle elevator
Comment: With the HLSL shader, the game quits with Abort trap: 6

Please feel free to ask me for any additional information, unfortunately I have no talent for coding, but I would like to help wherever possible.

My blog on MAME in Macs with a lot of BGFX stuff: https://mameonmacs.blogspot.co.at

Many thanks, Stefan

[estefan3112]

Hi, just to let you know that in r0ni's current MAME 0.188 build, the METAL backend works with me - http://sdlmame.lngn.net (considered as official Mac MAME build). However, r0ni compiles MAME under 10.9 with an updated LLVM installed through MacPorts. His make command is make PTR=1 TARGETOS=macosx TOOLS=1 NOWERRROR=1 -j5. Whereas the official compile instructions are just make -j5. I am under 10.12, but r0ni's compile still works for me. I will try to find out whether different compile instructions make the difference. Cheers.

[estefan3112]

Happy to report that the BGFX Metal backend now works in MAME 0.195, also if self-compiled. There seem to be other issues right now, such as a non-functioning hlsl chain, but in overall, it seems fair to close here.

[bkaradzic]

If you have issues like these in the future, the best would be to create simple repro inside bgfx examples, so that I can debug it. Something not working in MAME might be multiple things unrelated to bgfx, so simple repro inside bgfx examples would focus to just bgfx issue.

[estefan3112]

Hmmm, I try to understand your suggestion with my limited knowledge :). Unfortunately I do not code. Should I just try out the examples on my machine and report back? Sorry but it seems to be beyond my capabilities, still eager to understand :-).

[bkaradzic]

Examples are likely to work. You can report issue to MAME team, and they can then figure out what's wrong with bgfx and report it here.

[estefan3112]

Eager to help and to learn :-). Do you know whom to contact at MAME? When I reported this issue into mametesters, they just told me that I should contact you...