reset() {
		// cancel any sort operation
		if (this.pendingSort) {
			clearTimeout(this.pendingSort);
			this.pendingSort = null;
		}

		// delete all children
		const children = this.getChildren();
		for (let i = children.length, child; i >= 0; child = children[--i]) {
			// don't remove it if a persistent object
			if (child && child.isPersistent !== true) {
				this.removeChildNow(child);
			}
		}

		if (typeof this.currentTransform !== "undefined") {
			// just reset some variables
			this.currentTransform.identity();
		}

		this.backgroundColor.setColor(0, 0, 0, 0.0);
	}
reset the container, removing all childrens, and reseting transforms.