Setting up CIFilter in Swift

Question

How does one translate the last line of the following ObjC code to Swift:

CGAffineTransform transform = CGAffineTransformIdentity;
CIFilter *clampFilter = [CIFilter filterWithName:@"CIAffineClamp"];

[clampFilter setValue:[NSValue valueWithBytes:&transform objCType:@encode(CGAffineTransform)] forKey:@"inputTransform"];

The following line

clampFilter.setValue(transform, forKey: "inputTransform")

produces

Type 'CGAffineTransform' does not conform to protocol 'AnyObject'

Peptonize

Answer 1

NSValue has a constructor that takes a CGAffineTransform argument:

let transform = CGAffineTransformIdentity
let clampFilter = CIFilter(name: "CIAffineClamp")

let val = NSValue(CGAffineTransform: transform)
clampFilter.setValue(val, forKey: "inputTransform")

Update for Swift 3:

let transform = CGAffineTransform.identity
let clampFilter = CIFilter(name: "CIAffineClamp")!
let val = NSValue(cgAffineTransform: transform)
clampFilter.setValue(val, forKey: "inputTransform")

Preventer

It's crashing in Swift 3.1. Can you post any example of CIAffineClamp or CIAffineTile. – Comenius

@ChanWarde: Please check if the update works for you. – Preventer

hello @Martin R, it's not working even only "CIKaleidoscope" in TileEffect is working for me. All other filters are returning nil image. I don't find any example, question or reference for it. Can you please add some code. Or I should add a new question for it?? – Comenius

@ChanWarde: I would suggest to ask a new question. Don't forget to add the code that you tried and a clear description where it fails. – Preventer

Answer 2

This might do.

var transform = CGAffineTransformIdentity;
var clampFilter = CIFilter(name: "CIAffineClamp")
var value = NSValue(CGAffineTransform: transform)
clampFilter.setValue(value, forKey: "inputTransform")

Arch

You should always use let in swift unless you are specifically going to change the value in the future. – Speed