Wwise SDK 2018.1.11

Interpolation angle, in degrees, over which the fDiffractionShadowAttenFactor is applied.

At a diffraction of 0, a multiplier of 1 (ie. none) is applied, and at an angle of fDiffractionShadowDegrees or greater, fDiffractionShadowAttenFactor is applied. A linear interpolation between 1 and fDiffractionShadowAttenFactor is applied when the angle is between 0 and fDiffractionShadowDegrees.

AkSpatialAudio.h の 62 行目に定義があります。