resize(width, height) {
		const canvas = this.getCanvas();
		if (width !== canvas.width || height !== canvas.height) {
			canvas.width = width;
			canvas.height = height;
			this.currentScissor[0] = 0;
			this.currentScissor[1] = 0;
			this.currentScissor[2] = width;
			this.currentScissor[3] = height;
			// publish the corresponding event
			eventEmitter.emit(CANVAS_ONRESIZE, width, height);
		}
	}
resizes the system canvas
@param {number} width - new width of the canvas
@param {number} height - new height of the canvas