---
title: "scheduleParameterCurve(_:atTime:)"
framework: corehaptics
role: symbol
role_heading: Instance Method
path: "corehaptics/chhapticpatternplayer/scheduleparametercurve(_:attime:)"
---

# scheduleParameterCurve(_:atTime:)

Schedules a parameter curve to begin transitioning a parameter at a certain time.

## Declaration

```swift
func scheduleParameterCurve(_ parameterCurve: CHHapticParameterCurve, atTime time: TimeInterval) throws
```

## Parameters

- `parameterCurve`: The curve along which to vary the parameter.
- `time`: The time at which to begin applying the parameter curve.

## Discussion

Discussion Scheduling a parameter curve tells the haptic pattern player to vary a parameter gradually along the curve. For example, if the intensity of a haptic pattern is 0 at the time of application, then a curve created to set the haptic intensity to 1 will smoothly hit every single continuous value between 0 and 1 during the transition.

Scheduling a parameter curve is analogous to sending a dynamic parameter with sendParameters(_:atTime:); the only difference is that the curve transitions the parameter gradually, whereas the dynamic parameter changes the parameter immediately at a certain time. Schedule a parameter curve for one parameter at a time, and specify control points to characterize the curve’s shape. For more information on creating or specifying a parameter curve, see CHHapticParameterCurve.

## See Also

### Sending Parameters to a Haptic

- [sendParameters(_:atTime:)](corehaptics/chhapticpatternplayer/sendparameters(_:attime:).md)