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IDirectSound3DListener8::SetDopplerFactor 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 It has been superseded by WASAPI and Audio Graphs.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 SetDopplerFactor method sets the multiplier for the Doppler effect.

Syntax

HRESULT SetDopplerFactor(
         D3DVALUE flDopplerFactor,
         DWORD dwApply
)

Parameters

  • flDopplerFactor
    Doppler 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 Doppler factor has a range of DS3D_MINDOPPLERFACTOR (no Doppler effects) to DS3D_MAXDOPPLERFACTOR (defined as 10 times the Doppler effects found in the real world). The default value is DS3D_DEFAULTDOPPLERFACTOR (1.0).

Requirements

Header: Declared in DSound.h.

Library: Use Dsound3d.dll.

See Also

IDirectSound3DListener8