Source: src/ol/animation.jsdoc

/**
 * The animation static methods are designed to be used with the
 * {@link ol.Map#beforeRender} method.  For example:
 *
 *     var map = new ol.Map({ ... });
 *     var zoom = ol.animation.zoom({
 *       resolution: map.getView().getResolution()
 *     });
 *     map.beforeRender(zoom);
 *     map.getView().setResolution(map.getView().getResolution() * 2);
 *
 * @namespace ol.animation
 */