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IDirectSound3DListener8::SetDistanceFactor Method

[The feature associated with this page, DirectSound, is a legacy feature. It has been superseded by WASAPI and Audio Graphs. Media Casting have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Media Casting instead of DirectSound, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The SetDistanceFactor method sets the distance factor, which is the number of meters in a vector unit.

Syntax

HRESULT SetDistanceFactor(
         D3DVALUE flDistanceFactor,
         DWORD dwApply
)

Parameters

  • flDistanceFactor
    Distance 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.

Remarks

The distance factor has a range of DS3D_MINDISTANCEFACTOR to DS3D_MAXDISTANCEFACTOR, defined in Dsound.h as FLT_MIN and FLT_MAX respectively. The default value is DS3D_DEFAULTDISTANCEFACTOR, or 1.0.

Requirements

Header: Declared in DSound.h.

Library: Use Dsound3d.dll.

See Also

IDirectSound3DListener8