Wwise SDK

The maximum possible number of diffraction points at each end of a reflection path. Diffraction on reflection allows reflections to fade in and out smoothly as the listener or emitter moves in and out of the reflection's shadow zone. When greater than zero, diffraction rays are sent from the listener to search for reflections around one or more corners from the listener. Diffraction must be enabled on the geometry to find diffracted reflections (refer to AkGeometryParams). Set to 0 to disable diffraction on reflections.

AkSpatialAudio.h の 66 行目に定義があります。