An Example Of Animating SCNText With A Typewriter Like Effect

SCNText+Typewriter.swift

//1. Timer To Animate Our Text
var animationTimer: Timer?
    
//2. Variable To Store The Current Time
var time:Int  = 0

/// Animates The Presentation Of SCNText To Give An Appearance Of A Typing Effect
///
/// - Parameters:
///   - textGeometry: SCNText
///   - text: String
///   - completed: () -> Void
func animateTextGeometry(_ textGeometry: SCNText, withText text: String, completed: @escaping () -> Void ){
    
    //1. Get All The Characters From The Text
    let characters = Array(text)
    
    //2. Run The Animation
    animationTimer = Timer.scheduledTimer(withTimeInterval: 0.3, repeats: true) { [weak self] timer in
        
        //a. If The Current Time Doesnt Equal The Count Of Our Characters Then Continue To Animate Our Text
        if self?.time != characters.count {
            let currentText: String = textGeometry.string as! String
            textGeometry.string = currentText + String(characters[(self?.time)!])
            self?.time += 1
        }else{
            //b. Invalide The Timer, Reset The Variables & Escape
            timer.invalidate()
            self?.time = 0
            completed()
        }
    }
}