EmiterProvider.swift

//
//  EmitterProvider.swift
//
//  Created by Coder ACJHP on 15.04.2019.
//  Copyright © 2019 FitBest Bilgi Teknolojileri. All rights reserved.
//

import UIKit

class EmitterProvider {
    
    static func createEmitterLayer(onView: UIView, withShape: UIImage) {
        let layer = CAEmitterLayer()
        layer.emitterShape = .line
        layer.emitterCells = getCellList(withShape: withShape)
        layer.position = CGPoint(x: onView.frame.width / 2, y: 0)
        layer.emitterSize = CGSize(width: onView.frame.width, height: 2)
        onView.layer.insertSublayer(layer, at: 0)
    }
    
    private static func getCellList(withShape: UIImage) -> [CAEmitterCell] {
        var cellList = [CAEmitterCell]()
        
        let shapeCell = CAEmitterCell()
        shapeCell.contents = withShape.cgImage
        shapeCell.birthRate = 5
        shapeCell.lifetime = 40
        shapeCell.velocity = CGFloat(55)
        shapeCell.emissionLongitude = 180 * (.pi / 180)
        shapeCell.emissionRange = 45 * (.pi / 180)
        shapeCell.scale = 0.04
        shapeCell.scaleRange = 0.05
        cellList.append(shapeCell)
        return cellList
    }
}

How to use?

EmitterProvider.createEmitterLayer(onView: view, withShape: #imageLiteral(resourceName: "snowFlake"))