IDirectSound3DListener8::SetRolloffFactor Method

The SetRolloffFactor method sets the rolloff factor, which determines the rate of attenuation over distance.


HRESULT SetRolloffFactor(
         D3DVALUE flRolloffFactor,
         DWORD dwApply


  • flRolloffFactor
    Rolloff factor. D3DVALUE is defined as float.
  • dwApply
    Value that specifies when the setting should be applied. This value must be one of the following:
    Value Description
    DS3D_DEFERRED Settings are not applied until the application calls the CommitDeferredSettings method. This allows the application to change several settings and generate a single recalculation.
    DS3D_IMMEDIATE Settings are applied immediately, causing the system to recalculate the 3D coordinates for all 3D sound buffers.

Return Value

If the method succeeds, the return value is DS_OK. If the method fails, the return value may be DSERR_INVALIDPARAM.


The rolloff factor has a range of DS3D_MINROLLOFFFACTOR (no rolloff) to DS3D_MAXROLLOFFFACTOR (defined as 10 times the rolloff found in the real world). The default value is DS3D_DEFAULTROLLOFFFACTOR (1.0). For more information, see Rolloff Factor.


Header: Declared in DSound.h.

Library: Use Dsound3d.dll.

See Also