title: How to change the rotation point (Feature) on the map after it is created and added to map
body: <p>How is it possible to change the rotation icon (picture), points (Feature) after creating and adding to the map?</p>
  
  <p>Set the rotation icons on create a point I know, but how to change the rotation later?
  For uses such as icons, which follows the direction of rotation?</p>
  
  <p>How to do this correctly with respect to performance? (set point again all parameters???)</p>
  
  <p>thanks... very much</p>
  
  <p>Live demonstration:
  <a href="http://jsfiddle.net/91mLh1j7/" rel="nofollow noreferrer">http://jsfiddle.net/91mLh1j7/</a></p>
  
  <p>JS Code:</p>
  
  <pre class="lang-js prettyprint-override"><code>var map = new ol.Map({
      target: 'mapID',
      layers: [
      new ol.layer.Tile({
          source: new ol.source.MapQuest({
              layer: 'osm'
          })
      })],
      view: new ol.View({
          center: ol.proj.transform([14, 50], 'EPSG:4326', 'EPSG:3857'),
          zoom: 11
      })
  });
  
  
  
  var Features = [];
  // define style for features
  var iconStyle = {
      src: "http://google-maps-icons.googlecode.com/files/library-publ.png",
      anchorOrigin: "bottom-left",  // v KML je počítáno od levého spodního rohu
      anchor: [0.5, 0],
      anchorXUnits: "fraction",
      anchorYUnits: "fraction",
      scale: 0.9,
      opacity: 0.75,
      rotation: 45 * 0.01745329251,  // in rad / 360° = 6.28318531 rad = 2PI rad
      rotateWithView: "true"
  }; 
  
  
  var point1 = new ol.Feature({
      geometry: new ol.geom.Point(ol.proj.transform([14.01, 50.01], 'EPSG:4326',
          'EPSG:3857')),
      name: 'Point One'
  });
  point1.setStyle(new ol.style.Style({
      image: new ol.style.Icon(iconStyle)
  }));
  
  
  var point2 = new ol.Feature({
      geometry: new ol.geom.Point(ol.proj.transform([13.99, 49.99], 'EPSG:4326',
          'EPSG:3857')),
      name: 'Point Two'
  });
  point2.setStyle(new ol.style.Style({
      image: new ol.style.Icon(iconStyle)
  }));
  
  // add point1, point2 to Features 
  Features.push(point1);
  Features.push(point2);
  
  var vectorSource = new ol.source.Vector({
      features: Features  // add an array of features
  });
  var vectorLayer = new ol.layer.Vector({
      source: vectorSource  // add source for vectorLayer
  });
  
  map.addLayer(vectorLayer)  // add vectorLayer to map
  
  
  ////////////////////
  // how to change the rotation of one point (feature) ? after cration point and add it on map
  ////////////////////
  </code></pre>