---
title: lpEnvelope
framework: Force Feedback
role: symbol
role_heading: Instance Property
platforms: [Mac Catalyst 13.0+, macOS 10.2+]
path: forcefeedback/ffeffect/lpenvelope
---

# lpEnvelope

Optional pointer to a FFENVELOPE structure that describes the envelope to be used by this effect. Not all effect types use envelopes. If no envelope is to be applied, the member should be set to NULL.

## Declaration

```swift
var lpEnvelope: PFFENVELOPE!
```

## See Also

### Instance Properties

- [cAxes](forcefeedback/ffeffect/caxes.md)
- [cbTypeSpecificParams](forcefeedback/ffeffect/cbtypespecificparams.md)
- [dwDuration](forcefeedback/ffeffect/dwduration.md)
- [dwFlags](forcefeedback/ffeffect/dwflags.md)
- [dwGain](forcefeedback/ffeffect/dwgain.md)
- [dwSamplePeriod](forcefeedback/ffeffect/dwsampleperiod.md)
- [dwSize](forcefeedback/ffeffect/dwsize.md)
- [dwStartDelay](forcefeedback/ffeffect/dwstartdelay.md)
- [dwTriggerButton](forcefeedback/ffeffect/dwtriggerbutton.md)
- [dwTriggerRepeatInterval](forcefeedback/ffeffect/dwtriggerrepeatinterval.md)
- [lpvTypeSpecificParams](forcefeedback/ffeffect/lpvtypespecificparams.md)
- [rgdwAxes](forcefeedback/ffeffect/rgdwaxes.md)
- [rglDirection](forcefeedback/ffeffect/rgldirection.md)