AquaBrushedMetal.swift

import SwiftUI

struct AquaBrushedMetalShape: Shape {
  func path(in rect: CGRect) -> Path {
    Path {
      path in for _ in stride(from: 0, to: Int(rect.height), by: 5) {
        let y = CGFloat.random(in: rect.minY...rect.maxY)
        let curveEnd = CGPoint(x: rect.maxX, y: y)
        let controlOffset = CGFloat.random(in: -25...25)
        let controlPoint = CGPoint(x: rect.midX, y: y + controlOffset)
        
        path.move(to: CGPoint(x: rect.minX, y: y))
        path.addQuadCurve(to: curveEnd, control: controlPoint)
      }
    }
  }
}

struct AquaBrushedMetalView: View {
  let gradient = Gradient(
    colors: [.aquaTransparentWhite,
             .aquaTranslucentWhite,
             .aquaTransparentWhite])
  var body: some View {
    ZStack {
      Color.aquaGray
      AquaBrushedMetalShape()
        .stroke(Color.aquaBrushedMetalStroke, lineWidth: 2)
      LinearGradient(gradient: gradient ,
                     startPoint: .leading,
                     endPoint: .trailing)
    }
  }
}