はじめに
CIFilter関係の記事4日目です
サンプルアプリ
実装
import SwiftUI
struct ContentView: View {
private let image = UIImage(named: "sample")!
@State private var uiImage: UIImage?
var body: some View {
ScrollView {
VStack {
if let uiImage {
Image(uiImage: uiImage)
.resizable()
.scaledToFit()
} else {
Image(uiImage: image)
.resizable()
.scaledToFit()
}
HStack(spacing: 15) {
Button {
applyOverlayBlendFilter()
} label: {
Text("適用")
}
Button {
uiImage = nil
} label: {
Text("リセット")
}
}
}
.padding(.horizontal, 20)
}
}
func applyOverlayBlendFilter() {
let context = CIContext()
let inputImage = CIImage(image: image)!
let overlayColor = CIColor(red: 1.0, green: 0.0, blue: 0.0, alpha: 0.5)
guard let overlayFilter = CIFilter(name: "CIOverlayBlendMode", parameters: [
kCIInputImageKey: inputImage,
kCIInputBackgroundImageKey: CIImage(color: overlayColor)
]) else { return }
guard let outputImage = overlayFilter.outputImage else { return }
guard let cgImage = context.createCGImage(outputImage, from: inputImage.extent) else { return }
self.uiImage = UIImage(cgImage: cgImage)
}
}
おわり
やってることはSwiftUIの.blendMode(.overlay)
と同じです!