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# convertTime(_:from:)

Converts the time interval from the specified layer’s time space to the receiver’s time space.

```
func convertTime(_ t: CFTimeInterval, from l: CALayer?) -> CFTimeInterval
```

## Parameters

`t`

A point specifying a location in the coordinate system of `l`.

`l`

The layer with `t` in its time space. The receiver and `l` and must share a common parent layer.

## Return Value

The time interval converted to the receiver’s time space.

## Discussion

The following code shows the creation of two layers, layer and `offsetSlowMoLayer`. `offsetSlowMoLayer` has an offset time of 1 second and its [`speed`](/documentation/QuartzCore/CAMediaTiming/speed) is set to `0.5`.  The last line converts and prints a time interval of 0.5 seconds converted from the time space of `layer` to the time space of `offsetSlowMoLayer`.

```swift
let layer = CALayer()
let offsetSlowMoLayer = CALayer()
       
offsetSlowMoLayer.timeOffset = CFTimeInterval(1)
offsetSlowMoLayer.speed = 0.5
       
print(offsetSlowMoLayer.convertTime(CFTimeInterval(0.5), from: layer)) // prints 1.25
```

---

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