async setAnimationLoop( callback ) {

		if ( this._initialized === false ) await this.init();

		this._animation.setAnimationLoop( callback );

	}
Applications are advised to always define the animation loop
with this method and not manually with `requestAnimationFrame()`
for best compatibility.

@async
@param {?Function} callback - The application's animation loop.
@return {Promise} A Promise that resolves when the set has been executed.