ObjectPool - Very bare bones for maximum performance

ObjectPool.js

/* NOTES
	When i create 5 Float32Arrays at 10 million iterations, It takes about 3 seconds to complete.
	But if create a Pool of 5 Float arrays and use Get/Rtn at the same interactions is only 0.17s. 
	So by using ObjectPool, using Float32Arrays for Vector3 data is just as fast as an Object Vector
	but uses up less memory and affects garbage collection much less.
	
	let pool = new ObjectPool( THREE.Vector3, 10, 5 );
	let a = pool.get(),
		b = pool.get();
	pool.rtn( a ).rtn( b );
*/
class ObjectPool{
	constructor( obj, cnt=10, rCnt=5 ){
		this.maxIdx		= cnt-1;
		this.curIdx		= this.maxIdx;
		this.obj		= obj;
		this.pool		= new Array( cnt );
		this.resizeCnt	= rCnt;

		// Initialize the pool;
		for( let i=0; i < cnt; i++ ) this.pool[ i ] = new obj();
	}

	// Get an Item, Create more if not available
	// NOTES:
	// Using index instead of push / pop, shaves off an extra 0.07s on 10 million calls.
	get(){
		if( this.curIdx == -1 ){
			console.log("POOLRESIZE -", this.obj.name );

			let p = this.pool, t = this.obj;
			p.length += this.resizeCnt;

			for( let i=0; i < this.resizeCnt; i ++ ) p[i] = new t();
			this.maxIdx = p.length - 1;
			this.curIdx = this.resizeCnt-1;
		}

		return this.pool[ this.curIdx-- ];
	}

	// Return Single Item back to the Pool
	// NOTES:
	// Tried to use a Loop and Arguments array but that really
	// killed performance. Also did an instanceOf check before
	// allowing a return which eats up time. So sticking to
	// this bare bones rtn function gives me 10 million calls at 0.18 seconds.
	// with instanceOf, 2 seconds, with loop 7.6 seconds.
	rtn( o ){ this.pool[ ++this.curIdx ] = o; return this; }
}