步骤

1.创建发射器(CAEmitterLayer)
2.设置粒子属性

代码

  //创建发射器
        let emitterLayer = CAEmitterLayer();
        //设置发射器位置
        emitterLayer.emitterPosition = CGPoint(x: Screen_Width/2, y: Screen_Height )
        //开启三位效果
        emitterLayer.preservesDepth = true
        
        //创建粒子，并设置属性
        let cell = CAEmitterCell()
        //粒子速度
        cell.velocity = 150
        cell.velocityRange = 100
        
        //粒子大小
        cell.scale = 0.7
        cell.scaleRange = 0.3
        
        //粒子方向
        cell.emissionLongitude = -CGFloat.pi/2
        cell.emissionRange =  -CGFloat.pi/2/6
        
        //存活时间
        cell.lifetime = 3
        cell.lifetimeRange = 1.5
        
        //每秒弹出的个数
        cell.birthRate = 10
        
        //展示的图片
        cell.contents = UIImage(named: "good5_30x30_")?.cgImage
        
        //旋转
        cell.spin = CGFloat.pi/2/4
        cell.spinRange = CGFloat.pi/2/6
     
        emitterLayer.emitterCells = [cell]
        view.layer.addSublayer(emitterLayer)