[openal] Preparing for 1.18

[Chris Robinson]

On 05/28/2017 07:32 AM, Christian Hoene wrote:
> Hi Chris,
>
> sadly enough, support for SOFA files has not yet been added:
> https://github.com/kcat/openal-soft/pull/80
>
> Any changes that this extension (or a similar) to support powerful HRTFs will be considered at some times?

Supporting SOFA files is something I'm going to look into after 1.18 is 
released. In regards to that PR in particular, it seems quite a bit more 
complex than should be necessary given this loading function by 
comparison 
<https://github.com/sofacoustics/SOFAlizer/blob/master/modules/audio_filter/sofalizer/sofalizer.c#L286>. 
It should only need a relatively minor change to makehrtf.c to use an 
alternate loading function to prepare the HrirDataT structure from a 
SOFA file.

I've done tests to successfully load a .sofa file in an independent app, 
but there's some things to work out before being able to make mhr files 
out of them (such as checking for and dealing with irregular layouts, 
where a ring of measurements are not equally spaced; and it would 
greatly benefit from stereo/dual-ear measurements). And considering how 
long it's been since the last release and not knowing how long it would 
take to work the issues out, it's on hold until after the release.