OpenAL and microphone on macos using the mobile pkg

[whiteh...@googlemail.com]

go1.12  macos 10.12.4

I haven't been able to find a Go example of this being used so far.  However I found a C example that I'm porting over to Go that access the microphone.

All I'm doing so far is 'al.OpenDevice()'

running 'gomobile build' generates this error:

...golang.org/x/mobile/exp/audio/al/al_android.go:13:10: fatal error: 'AL/al.h' file not found

Working on the assumption that the openal might be missing on my system, I have run this: 'brew install openal-soft'




That hasn't solved the problem.  I took note of the following when doing the brew install, but it also hasn't helped.





For compilers to find openal-soft you may need to set:
  export LDFLAGS="-L/usr/local/opt/openal-soft/lib"
  export CPPFLAGS="-I/usr/local/opt/openal-soft/include"








Any tips please? the file does appear to be in that location.





btw Since I'm new here, is it okay to ask for help here?  or do you prefer stackoverflow?





[ma...@eliasnaur.com]

I don't use the openal package myself, but I believe you need to set CGO_CFLAGS=-I/usr/local/opt/openal-soft/include.

- elias

[whiteh...@googlemail.com]

Thanks! That got me some steps further down the rabbit hole :)

gomobile: the Android requires the golang.org/x/mobile/exp/audio/al, but the OpenAL libraries was not found. Please run gomobile init with the -openal flag pointing to an OpenAL source directory.

So first I tried 'brew reinstall --build-from-source openal-soft'  but there were still no sources in that directory (although everything built fine).

Next I located the downloaded brew .bz2 file, which was located in: '~/Library/Caches/Homebrew' and using a symlink of 'openal-soft--1.19.1.tar.bz2'





Manually unpacking that, and then running a new gomobile init pointing to that directory got me some distance further before sadly failing.





[  2%] Building C object CMakeFiles/common.dir/common/alcomplex.c.o
In file included from /Users/me/openal-soft-1.19.1/common/alcomplex.c:5:


/Users/me/openal-soft-1.19.1/common/math_defs.h:36:21: error: static declaration of 'log2f' follows non-static declaration
static inline float log2f(float f)
                    ^
/Users/me/go/pkg/gomobile/ndk-toolchains/arm/bin/../sysroot/usr/local/include/math.h:38:15: note: previous declaration is here
float         log2f(float);


Is there anyway to bypass this step of having to rebuild OpenAL?

[Elias Naur]

On Thu, Mar 7, 2019 at 11:11 PM whitehexagon via golang-nuts
<golan...@googlegroups.com> wrote:
>
> Thanks! That got me some steps further down the rabbit hole :)
>
> gomobile: the Android requires the golang.org/x/mobile/exp/audio/al, but the OpenAL libraries was not found. Please run gomobile init with the -openal flag pointing to an OpenAL source directory.
>
> So first I tried 'brew reinstall --build-from-source openal-soft' but there were still no sources in that directory (although everything built fine).
>
> Next I located the downloaded brew .bz2 file, which was located in: '~/Library/Caches/Homebrew' and using a symlink of 'openal-soft--1.19.1.tar.bz2'
>
> Manually unpacking that, and then running a new gomobile init pointing to that directory got me some distance further before sadly failing.
>
> [ 2%] Building C object CMakeFiles/common.dir/common/alcomplex.c.o
> In file included from /Users/me/openal-soft-1.19.1/common/alcomplex.c:5:
> /Users/me/openal-soft-1.19.1/common/math_defs.h:36:21: error: static declaration of 'log2f' follows non-static declaration
> static inline float log2f(float f)
> ^
> /Users/me/go/pkg/gomobile/ndk-toolchains/arm/bin/../sysroot/usr/local/include/math.h:38:15: note: previous declaration is here
> float log2f(float);
>
> Is there anyway to bypass this step of having to rebuild OpenAL?
>
>

I don't think there's a way around it, unfortunately. As far as I
know, there are no prebuilt openal libraries for Android available.

I'm not even sure openal builds with a recent NDK where gcc is gone
and replaced with clang.

- elias

[whiteh...@googlemail.com]

Ah of course, it has to rebuild per target platform.  Looking further at the mobile API I'm not sure it includes the Capture part of OpenAL anyway. 

I'll have a look at kotlin-native for this part of my functionality.  Thank you for your help. Peter