ContentView.swift

//
//  ContentView.swift
//  Snowglobe
//
//  Created by Kelly Lougheed on 12/14/20.
//

import SwiftUI

struct ContentView: View {
    let numParticles: Int = 200
    
    var body: some View {
        ZStack {
            Color.black.ignoresSafeArea()
            ForEach(0..<numParticles) { index in
                Particle()
            }
        }
    }
}

struct Particle: View {
    
    @State private var onFloor: Bool = false
    
    var scaleNum: CGFloat = CGFloat.random(in: 3...8)
    
    var animation = Animation.linear(duration: Double.random(in: 1...5)).repeatForever(autoreverses: false)
    
    var body: some View {
        GeometryReader { geo in
            Circle()
                .fill(Color.white)
                .frame(width: scaleNum, height: scaleNum)
                .offset(x: 0, y: onFloor ? geo.size.height : CGFloat(0))
                .position(x: CGFloat(Int.random(in: 0...Int(geo.size.width))))
                .blur(radius: 1)
                .onAppear() {
                    withAnimation(animation) {
                        onFloor.toggle()
                    }
                }
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}