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DIPERIODIC Structure

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Contains type-specific information for effects that are marked as DIEFT_PERIODIC.

The structure describes a periodic effect.

A pointer to a single DIPERIODIC structure for an effect is passed in the lpvTypeSpecificParams member of the DIEFFECT structure.

Syntax

typedef struct DIPERIODIC {
    DWORD dwMagnitude;
    LONG lOffset;
    DWORD dwPhase;
    DWORD dwPeriod;
} DIPERIODIC, *LPDIPERIODIC;

Members

  • dwMagnitude
    Magnitude of the effect, in the range from 0 through 10,000. If an envelope is applied to this effect, the value represents the magnitude of the sustain. If no envelope is applied, the value represents the amplitude of the entire effect.
  • lOffset
    Offset of the effect. The range of forces generated by the effect is lOffset minus dwMagnitude to lOffset plus dwMagnitude. The value of the lOffset member is also the baseline for any envelope that is applied to the effect.
  • dwPhase
    Position in the cycle of the periodic effect at which playback begins, in the range from 0 through 35,999. See Remarks.
  • dwPeriod
    Period of the effect, in microseconds.

Remarks

A device driver cannot provide support for all values in the dwPhase member. In this case, the value is rounded off to the nearest supported value.