An array of Core Image filters to apply to the contents of the layer and its sublayers. Animatable.
SDKs
- iOS 2.0+
- macOS 10.5+
- Mac Catalyst 13.0+
- tvOS 9.0+
Framework
- Core Animation
Declaration
var filters: [Any]? { get set }
Discussion
The filters you add to this property affect the content of the layer, including its border, filled background and sublayers. The default value of this property is nil.
Changing the inputs of the CIFilter object directly after it is attached to the layer causes undefined behavior. It is possible to modify filter parameters after attaching them to the layer but you must use the layer’s set method to do so. In addition, you must assign a name to the filter so that you can identify it in the array. For example, to change the input parameter of the filter, you could use code similar to the following:
let layer = CALayer()
if let filter = CIFilter(name:"CIGaussianBlur") {
filter.name = "myFilter"
layer.backgroundFilters = [filter]
layer.setValue(1,
forKeyPath: "backgroundFilters.myFilter.inputRadius")
}
Listing 2 shows how to create a text layer and apply a CIPointillize filter to it.
Applying a pointillize filter to a text layer
view.layer = CALayer()
view.layerUsesCoreImageFilters = true
let textLayer = CATextLayer()
textLayer.string = "Core Animation"
textLayer.foregroundColor = NSColor.blue.cgColor
textLayer.backgroundColor = NSColor.lightGray.cgColor
textLayer.alignmentMode = kCAAlignmentCenter
textLayer.fontSize = 100
textLayer.frame = CGRect(x: 10, y: 10, width: 700, height: 140)
if let filter = CIFilter(name: "CIPointillize",
withInputParameters: ["inputRadius": 6]) {
textLayer.filters = [filter]
}
view.layer?.addSublayer(textLayer)
Figure 1 shows the result: a pointillist effect is added to the text.
Text layer with applied filter
Special Considerations
This property is not supported on layers in iOS.