Switchable Corner Shapes in SwiftUI

CornerRadii.swift

public struct AlbumArtView: View {
    
    var useContainerRelativeShape: Bool = false

    public var body: some View {
        // Option 1
        overlayView(for: 2.0)

        // Option 2
        roundedCornerShape
            .strokeBorder(.white, lineWidth: 2.0 * scale)
            .blendMode(.plusLighter)

    }

    // Option 1
    private var roundedCornerShape: AnyShape {
        if useContainerRelativeShape {
            return AnyShape(ContainerRelativeShape())
        } else {
            return AnyShape(RoundedRectangle(cornerRadius: cornerRadius, style: .continuous))
        }
    }

    // Option 2
    @ViewBuilder
    func overlayView(for scale: CGFloat) -> some View {
        if useContainerRelativeShape {
            ContainerRelativeShape()
                .strokeBorder(.white, lineWidth: 2.0 * scale)
                .blendMode(.plusLighter)
        } else {
            RoundedRectangle(cornerRadius: cornerRadius, style: .continuous)
                .strokeBorder(.white, lineWidth: 2.0 * scale)
                .blendMode(.plusLighter)
        }
    }

}