---
title: alphaSpeed
framework: quartzcore
role: symbol
role_heading: Instance Property
path: quartzcore/caemittercell/alphaspeed
---

# alphaSpeed

The speed, in seconds, at which the alpha component changes over the lifetime of the cell. Animatable.

## Declaration

```swift
var alphaSpeed: Float { get set }
```

## Discussion

Discussion The speed change is defined as the rate of change per second. The default value of this property is 0.

## See Also

### Setting Emitter Cell Visual Attributes

- [isEnabled](quartzcore/caemittercell/isenabled.md)
- [color](quartzcore/caemittercell/color.md)
- [redRange](quartzcore/caemittercell/redrange.md)
- [greenRange](quartzcore/caemittercell/greenrange.md)
- [blueRange](quartzcore/caemittercell/bluerange.md)
- [alphaRange](quartzcore/caemittercell/alpharange.md)
- [redSpeed](quartzcore/caemittercell/redspeed.md)
- [greenSpeed](quartzcore/caemittercell/greenspeed.md)
- [blueSpeed](quartzcore/caemittercell/bluespeed.md)
- [magnificationFilter](quartzcore/caemittercell/magnificationfilter.md)
- [minificationFilter](quartzcore/caemittercell/minificationfilter.md)
- [minificationFilterBias](quartzcore/caemittercell/minificationfilterbias.md)
- [scale](quartzcore/caemittercell/scale.md)
- [scaleRange](quartzcore/caemittercell/scalerange.md)
- [contentsScale](quartzcore/caemittercell/contentsscale.md)