three.js/src/utils.js

function arrayMin( array ) {

	if ( array.length === 0 ) return Infinity;

	let min = array[ 0 ];

	for ( let i = 1, l = array.length; i < l; ++ i ) {

		if ( array[ i ] < min ) min = array[ i ];

	}

	return min;

}

function arrayMax( array ) {

	if ( array.length === 0 ) return - Infinity;

	let max = array[ 0 ];

	for ( let i = 1, l = array.length; i < l; ++ i ) {

		if ( array[ i ] > max ) max = array[ i ];

	}

	return max;

}

const TYPED_ARRAYS = {
	Int8Array: Int8Array,
	Uint8Array: Uint8Array,
	Uint8ClampedArray: Uint8ClampedArray,
	Int16Array: Int16Array,
	Uint16Array: Uint16Array,
	Int32Array: Int32Array,
	Uint32Array: Uint32Array,
	Float32Array: Float32Array,
	Float64Array: Float64Array
};

function getTypedArray( type, buffer ) {

	return new TYPED_ARRAYS[ type ]( buffer );

}

function createElementNS( name ) {

	return document.createElementNS( 'http://www.w3.org/1999/xhtml', name );

}

/**
  * cyrb53 hash for string from: https://stackoverflow.com/a/52171480
  *
  * Public Domain, @bryc - https://stackoverflow.com/users/815680/bryc
  *
  * It is roughly similar to the well-known MurmurHash/xxHash algorithms. It uses a combination
  * of multiplication and Xorshift to generate the hash, but not as thorough. As a result it's
  * faster than either would be in JavaScript and significantly simpler to implement. Keep in
  * mind this is not a secure algorithm, if privacy/security is a concern, this is not for you.
  *
  * @param {string} str
  * @param {number} seed, default 0
  * @returns number
  */
function hashString( str, seed = 0 ) {

	let h1 = 0xdeadbeef ^ seed, h2 = 0x41c6ce57 ^ seed;

	for ( let i = 0, ch; i < str.length; i ++ ) {

		ch = str.charCodeAt( i );

		h1 = Math.imul( h1 ^ ch, 2654435761 );

		h2 = Math.imul( h2 ^ ch, 1597334677 );

	}

	h1 = Math.imul( h1 ^ ( h1 >>> 16 ), 2246822507 ) ^ Math.imul( h2 ^ ( h2 >>> 13 ), 3266489909 );

	h2 = Math.imul( h2 ^ ( h2 >>> 16 ), 2246822507 ) ^ Math.imul( h1 ^ ( h1 >>> 13 ), 3266489909 );

	return 4294967296 * ( 2097151 & h2 ) + ( h1 >>> 0 );

}

export { arrayMin, arrayMax, getTypedArray, createElementNS, hashString };