// TextScramble class TextScramble { constructor(el) { this.el = el this.chars = '!<>-_\\/[]{}—=+*^?#________' this.update = this.update.bind(this) } setText(newText) { const oldText = this.el.innerText const length = Math.max(oldText.length, newText.length) const promise = new Promise((resolve) => this.resolve = resolve) this.queue = [] for (let i = 0; i < length; i++) { const from = oldText[i] || '' const to = newText[i] || '' const start = Math.floor(Math.random() * 40) const end = start + Math.floor(Math.random() * 40) this.queue.push({from, to, start, end}) } cancelAnimationFrame(this.frameRequest) this.frame = 0 this.update() return promise } update() { let output = '' let complete = 0 for (let i = 0, n = this.queue.length; i < n; i++) { let {from, to, start, end, char} = this.queue[i] if (this.frame >= end) { complete++ output += to } else if (this.frame >= start) { if (!char || Math.random() < 0.28) { char = this.randomChar() this.queue[i].char = char } output += `${char}` } else { output += from } } this.el.innerHTML = output if (complete === this.queue.length) { this.resolve() } else { this.frameRequest = requestAnimationFrame(this.update) this.frame++ } } randomChar() { return this.chars[Math.floor(Math.random() * this.chars.length)] } } const phrases = [ "Hey!", "That's my page!", "if you like", "check out", "my social media", "below :D" ] const el = document.querySelector('.text') const fx = new TextScramble(el) let counter = 0 const next = () => { fx.setText(phrases[counter]).then(() => { setTimeout(next, 600) }) counter = (counter + 1) % phrases.length } next()