function scale(game, x, y) {
	let renderer = game.renderer;
	let canvas = renderer.getCanvas();
	let context = renderer.getContext();
	let settings = renderer.settings;
	let pixelRatio = device.devicePixelRatio;

	let w = (settings.zoomX = canvas.width * x * pixelRatio);
	let h = (settings.zoomY = canvas.height * y * pixelRatio);

	// update the global scale variable
	renderer.scaleRatio.set(x * pixelRatio, y * pixelRatio);

	// adjust CSS style based on device pixel ratio
	canvas.style.width = w / pixelRatio + "px";
	canvas.style.height = h / pixelRatio + "px";

	// if anti-alias and blend mode were resetted (e.g. Canvas mode)
	renderer.setAntiAlias(context, settings.antiAlias);
	renderer.setBlendMode(settings.blendMode, context);

	// force repaint
	game.repaint();
}
scale the "displayed" canvas by the given scalar.
this will modify the size of canvas element directly.
Only use this if you are not using the automatic scaling feature.
@private
@param {Application} game - the game application instance triggering the resize
@param {number} x - x scaling multiplier
@param {number} y - y scaling multiplier