A simple script to generate pseudo-random titles for an adventure game, a la One Page Dungeon

titles-v1.js

/* outputs a simple string comprised of strings from a dictionary */

var game = window.game || {};

// inspired by https://watabou.itch.io/one-page-dungeon
game.titles = {
	'typ': ['Temple', 'Prison', 'House', 'Mansion', 'Dungeon', 'World', 'Castle', 'Graveyard', 'Library', 'Water World'],
	'adjektiv': ['Void', 'Blood', 'Burnt', 'Undead', 'Frozen', 'Night'],
	'name': ['Queen', 'Prince', 'King', 'Delila']
}

game.randomArrayItem = function(arr) {
	const randomIndex = Math.floor(Math.random() * arr.length);

	return arr[randomIndex];
}

game.generateTitle = function() {
	const typ = game.randomArrayItem(game.titles.typ);
	const adjektiv = game.randomArrayItem(game.titles.adjektiv);
	const name = game.randomArrayItem(game.titles.name);

	return typ + ' of the ' + adjektiv + ' ' + name;
}

game.init = function() {
	const mapTitle = game.generateTitle();
	document.querySelector('h1').textContent = mapTitle;
}

window.addEventListener('DOMContentLoaded', game.init);

titles-v2.js

/* this improves upon v1 with a simple way to expand sentence structure and allow for multiple uses of title variables */

var game = window.game || {};

// inspired by https://watabou.itch.io/one-page-dungeon
game.titles = {
	'type': ['Temple', 'Prison', 'House', 'Mansion', 'Dungeon', 'World', 'Castle', 'Graveyard', 'Library', 'Visage', 'Monument', 'Sin', 'Rise'],
	'descriptor': ['Void', 'Blood', 'Burnt', 'Undead', 'Frozen', 'Night', 'Drowned', 'Moonlight', 'Sun', 'Poisoned', 'Invisible', 'Ancient'],
	'actor': ['Queen', 'Prince', 'King', 'Elder', 'Scholar', 'Statue', 'Serpent', 'Slave Master', 'Lord', 'Lady', 'Demon', 'Caretaker'],
	'sentences': [
		'{type} of the {descriptor} {actor}',
		'The {actor}\'s {descriptor} {type}',
		'The {actor}\'s {type}',
		'The {actor} and the {descriptor} {actor}',
		'The {descriptor} {type}'
	]
}

game.randomArrayItem = function(arr) {
	if (!arr || arr.length === 0) return false;

	return arr[Math.floor(Math.random() * arr.length)];
}

game.extractRandomArrayItem = function(name) {
	if (!name) return false;

	const randomIndex = Math.floor(Math.random() * game.titles[name].length);
	const extractedString = game.titles[name][randomIndex];

	// remove the string from the array
	game.titles[name].splice(randomIndex, 1);

	return extractedString;
}

game.generateTitle = function() {
	let sentence = game.randomArrayItem(game.titles.sentences);

	for (item of ['type', 'descriptor', 'actor']) {
		// how many occurrences of this string?
		let pattern = new RegExp('{'+item+'}', 'g');
		const amount = (sentence.match(pattern) || []).length;

		// replace each occurrence with a unique random string
		for (let i = 0; i < amount; i += 1) {
			const word = game.extractRandomArrayItem(item);

			pattern = new RegExp('{'+item+'}');
			sentence = sentence.replace(pattern, word);
		}
	}

	return sentence;
}

game.init = function() {
	const mapTitle = game.generateTitle();
	document.querySelector('h1').textContent = mapTitle;
}

window.addEventListener('DOMContentLoaded', game.init);