Source code for CodeSlicing episode demonstrating how PureSwiftUI can clean up the Apple tutorial on drawing paths and shapes

MountainBadge.swift

//
//  MountainBadge.swift
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy
//  of this software and associated documentation files (the "Software"), to deal
//  in the Software without restriction, including without limitation the rights
//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
//  of the Software, and to permit persons to whom the Software is furnished to do so,
//  subject to the following conditions:
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
//  INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
//  PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
//  COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
//  AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
//  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//  Copyright © 2020 Adam Fordyce. All rights reserved.
//

import PureSwiftUI

private let mountainLayoutConfig = LayoutGuideConfig.grid(
    columns: [0, 0.24, 0.3, 0.5, 0.7, 0.76, 1],
    rows: [0, 0.265, 0.465, 0.523, 0.552, 0.638, 1])

private let backgroundLayoutConfig =
LayoutGuideConfig.polar(rings: [0.9, 1], segments: 72)

struct MountainBadge: View {
    
    var body: some View {
        GeometryReaderStack { (geo: GeometryProxy) in
            ZStack {
                BackgroundShape()
                    .fill(LinearGradient([
                        (.rgb8(239, 120, 221), 0),
                        (.rgb8(239, 172, 120), 0.6),
                    ], to: .bottom))
                    .layoutGuide(backgroundLayoutConfig, color: .red, lineWidth: 1)
                ForEach(0..<8) { index in
                    MountainShape()
                        .scale(0.34)
                        .fillColor(.rgb8(79, 79, 191))
                        .yOffset(-geo.minDimension * 0.218)
                        .rotate(45.degrees * index)
                }
                .opacity(0.5)
            }
            .frame(geo.minDimension)
        }
    }
}

private struct MountainShape: Shape {
    
    func path(in rect: CGRect) -> Path {
        Path { path in
            let g = mountainLayoutConfig.layout(in: rect)
                .scaled(0.5, anchor: .bottom)
                .rotated(90.degrees, anchor: .bottom)
            
            // mountain base
            path.shape([
                g.bottomLeading,
                g[1, 5],
                g[3, 3],
                g[5, 5],
                g.bottomTrailing
            ])

            // mountain peak
            path.shape([
                g[2, 4],
                g[3, 1],
                g[4, 4],
                g[3, 2]
            ])
        }
    }
}

private struct MountainShapeWithRectCoordinates: Shape {
    
    func path(in rect: CGRect) -> Path {
        Path { path in
            
            // mountain base
            path.shape([
                rect.bottomLeading,
                rect[0.24, 0.638],
                rect[0.5, 0.523],
                rect[0.76, 0.638],
                rect.bottomTrailing
            ])

            // mountain peak
            path.shape([
                rect[0.3, 0.552],
                rect[0.5, 0.265],
                rect[0.7, 0.552],
                rect[0.5, 0.465]
            ])
        }
    }
}

private struct MountainShapeWithRelativeLayoutCoordinates: Shape {
    
    func path(in rect: CGRect) -> Path {
        Path { path in
            
            let g = LayoutGuide.grid(rect, columns: 1, rows: 1)
            
            // mountain base
            path.shape([
                g.bottomLeading,
                g[rel: 0.24, rel: 0.638],
                g[rel: 0.5, rel: 0.523],
                g[rel: 0.76, rel: 0.638],
                g.bottomTrailing
            ])

            // mountain peak
            path.shape([
                g[rel: 0.3, rel: 0.552],
                g[rel: 0.5, rel: 0.265],
                g[rel: 0.7, rel: 0.552],
                g[rel: 0.5, rel: 0.465]
            ])
        }
    }
}


private struct BackgroundShape: Shape {

    func path(in rect: CGRect) -> Path {
        Path { path in
            let p = backgroundLayoutConfig.layout(in: rect)
            
            path.shape([
                p[1, 0],
                p[0, 13],
                p[0, 23],
                p[1, 36],
                p[0, 49],
                p[0, 59],
            ], cornerRadius: rect.widthScaled(0.15))
        }
    }
}

struct DrawingPathsAndShapesTest01_Previews: PreviewProvider {
    struct DrawingPathsAndShapesTest01_Harness: View {

        var body: some View {
            VStack {
                Group {
                    MountainBadge()
                        .layoutGuide(backgroundLayoutConfig)
                    Image("drawingpathsandshapes.mountain.badge")
                        .resizedToFill()
                }
                .frame(400)
            }
            .ignoresSafeArea()
        }
    }

    static var previews: some View {
        DrawingPathsAndShapesTest01_Harness()
            .showLayoutGuides(true)
            .previewDevice(.iPhone_12_Pro_Max)
    }
}