Native Source code for CodeSlicing episode on Animated Weather Icons Part 2 - Creating the Sun

WeatherIconSunDemoNative.swift

//
//  WeatherIconSunDemoNative.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.
//
//  Created by Adam Fordyce on 18/04/2021.
//  Copyright © 2021 Adam Fordyce. All rights reserved.
//

import SwiftUI

private struct SunElement: View {

    let showingRays: Bool

    var body: some View {
        SunView(showingRays: showingRays)
            .scaleEffect(0.7)
    }
}

private struct SunView: View {

    let showingRays: Bool

    @State private var rotatingRays = false

    var body: some View {
        GeometryReader { (geo: GeometryProxy) in
            
            let rayWidth = geo.size.width * 0.08
            let rayHeight = geo.size.height * 0.2
            let rayOffset = geo.size.width * -0.4
            let sunDiameter = geo.size.width * 0.45
            ZStack {
                ForEach(0..<8) { rayIndex in
                    Capsule()
                        .fill(Color.yellow)
                        .frame(width: rayWidth, height: rayHeight)
                        .offset(y: showingRays ? rayOffset : 0)
                        .rotationEffect(.degrees(Double(45 * rayIndex)))
                }
                
                .rotationEffect(.degrees(rotatingRays ? 360 : 0))
                
                Circle()
                    .fill(Color.yellow)
                    .frame(width: sunDiameter, height: sunDiameter)
            }
            .frame(maxWidth: .infinity, maxHeight: .infinity)
        }
        .onAppear {
            withAnimation(Animation.linear(duration: 8).repeatForever(autoreverses: false)) {
                rotatingRays = true
            }
        }
    }
}

struct WeatherIconSunDemoNative_Previews: PreviewProvider {
    struct WeatherIconSunDemoNative_Harness: View {

        @State private var showingRays = false
        var body: some View {
            ZStack {
//                Image(systemName: "sun.max.fill")
//                    .resizable()
//                    .aspectRatio(contentMode: .fit)
//                    .foregroundColor(.black.opacity(0.2))
                SunElement(showingRays: showingRays)
            }
            .frame(width: 400, height: 400)
            .onAppear {
                withAnimation {
                    showingRays = true
                }
            }
        }
    }

    static var previews: some View {
        WeatherIconSunDemoNative_Harness()
            .padding(50)
            .previewLayout(.sizeThatFits)
            .previewDevice("iPhone 12 Pro Max")
            .previewDisplayName("iPhone 12 Pro Max")
    }
}