It seems a simple scaling on the coefficients will allow first-order content to
work with second- and third-order coefficients, although obviously not with any
improved locality. That may be something to look into for the future, but this
is good enough for now.
For sources with a non-0 radius:
When distance <= radius, factor = distance/radius*0.5
When distance > radius, factor = 1 - asinf(radius/distance)/PI
Also, avoid using Position after calculating the localized direction and
distance.
This basically acts as if the app created a new context with the specified
attributes (causing the device to reset with new parameters), then immediately
delete it. Existing contexts remain undisturbed, except for a temporary pause
while the device output is reconfigured.
DISABLED - Generic disabled status
ENABLED - Generic enabled status
DENIED - Not allowed (user has configured HRTF to be off)
REQUIRED - Forced (user has forced HRTF to be used)
HEADPHONES_DETECTED - Enabled because headphones were detected
UNSUPPORTED_FORMAT - Device format is not compatible with available filters
This method is intended to help development by easily testing the quality of
the B-Format encode and B-Format-to-HRTF decode. When used with HRTF, all
sources are renderer using the virtual B-Format output, rather than just
B-Format sources.
Despite the CPU cost savings (only four channels need to be filtered with HRTF,
while sources all render normally), the spatial acuity offered by the B-Format
output is pretty poor since it's only first-order ambisonics, so "full" HRTF
rendering is definitely preferred.
It's /possible/ for some systems to be edge cases that prefer the CPU cost
savings provided by basic over the sharper localization provided by full, and
you do still get 3D positional cues, but this is unlikely to be an actual use-
case in practice.
It's possible to calculate HRTF coefficients for full third-order ambisonics
now, but it's still not possible to use them here without upmixing first-order
content.
This adds the ability to directly decode B-Format with HRTF, though only first-
order (WXYZ) for now. Second- and third-order would be easilly doable, however
we'd need to be able to up-mix first-order content (from the BFORMAT2D and
BFORMAT3D buffer formats) since it would be inappropriate to decode lower-order
content with a higher-order decoder.
Because on Windows, traced strings are written to a char string, which causes
UTF-16 strings to be converted to a narrow (non-UTF-8) encoding, potentially
losing characters.