AngularJS - Directives vs Controllers

Question

I am trying to create my first app using AngularJS. However, I'm a bit confused if I need to use directives for my particular case.

I have a simple Map page, where I need to show lat/lon value of selected region. At the moment I'm not using directives at all. I do everything in controller and use partials to display the results. I am not planning to reuse my map view in any other place. That's why I didn't feel I would need a directive.

On the other hand, I read somewhere that every time you try to manipulate DOM in your controller(which I'm doing using google maps API), you should move that part to directives.

Here's my simple controller:

function MapViewController($scope) {
  $scope.zoom = 6;
  $scope.lat = 37;
  $scope.lon = -122;
  var mapOptions = {
    center: new google.maps.LatLng($scope.lat, $scope.lon),
    zoom: $scope.zoom,
    mapTypeId: google.maps.MapTypeId.HYBRID
  };
  $scope.map = new google.maps.Map(
      document.getElementById('map-canvas'), mapOptions);

  /*
   * Update zoom and other map attributes.
   */
  google.maps.event.addListener($scope.map, 'center_changed', function() {
    $scope.$apply(function () {
      $scope.zoom = $scope.map.getZoom();
      var center = $scope.map.getCenter();
      $scope.lat = center.lat();
      $scope.lon = center.lng();
      var bounds = $scope.map.getBounds();
      var northEast = bounds.getNorthEast();
      $scope.northEastLat = northEast.lat();
      $scope.northEastLon = northEast.lng();
      var southWest = bounds.getSouthWest();
      $scope.southWestLat = southWest.lat();
      $scope.southWestLon = southWest.lng();
    });
  });

  /*
   * Set zoom and other map attributes.
   */
  google.maps.event.addListener($scope.map, 'some event', function() {
    $scope.$apply(function () {
      ...
    });
  });

  /*
   * Add markers to map.
   */
  google.maps.event.addListener($scope.map, 'another event', function() {
    $scope.$apply(function () {
      ...
    });
  });

}

And here's my partials:

  <div id="map-controllers" class="span4">
    <form class="form-horizontal">
      <div class="control-group">
        <label class="control-label" for="inputNumber">Zoom:</label>
        <div class="controls">
          <input type="text" class="input-mini" placeholder="zoom" value="{{ zoom }}">
        </div>
      </div>
      <div class="control-group">
        <label class="control-label" for="inputNumber">Latitude:</label>
        <div class="controls">
          <input type="text" class="input-large" placeholder="Latitude" value="{{ lat }}">
        </div>
      </div>
      <div class="control-group">
        <label class="control-label" for="inputNumber">Longitude:</label>
        <div class="controls">
          <input type="text" class="input-large" placeholder="Longitude" value="{{ lon }}">
        </div>
      </div>
      <div class="control-group">
        <label class="control-label" for="inputNumber">North East Latitude:</label>
        <div class="controls">
          <input type="text" class="input-large" placeholder="Latitude" value="{{ northEastLat }}">
        </div>
      </div>
      <div class="control-group">
        <label class="control-label" for="inputNumber">North East Longitude:</label>
        <div class="controls">
          <input type="text" class="input-large" placeholder="Longitude" value="{{ northEastLon }}">
        </div>
      </div>
      <div class="control-group">
        <label class="control-label" for="inputNumber">South West Latitude:</label>
        <div class="controls">
          <input type="text" class="input-large" placeholder="Latitude" value="{{ southWestLat }}">
        </div>
      </div>
      <div class="control-group">
        <label class="control-label" for="inputNumber">South West Longitude:</label>
        <div class="controls">
          <input type="text" class="input-large" placeholder="Longitude" value="{{ southWestLon }}">
        </div>
      </div>
    </form>
  </div>

Answer 1

Here's a brief stand-alone answer, with links to official docs for further info (definition of "services" added for good measure):

http://docs.angularjs.org/guide/controller

In AngularJS, a controller is a JavaScript constructor function that is used to augment the AngularJS scope.

When a controller is attached to the DOM via the ng-controller directive, AngularJS will instantiate a new controller object, using the specified controller's constructor function. A new child scope will be available as an injectable parameter to the controller's constructor function as $scope.

http://docs.angularjs.org/guide/directive

At a high level, directives are markers on a DOM element (such as an attribute, element name, or CSS class) that tell AngularJS's HTML compiler ($compile) to attach a specified behavior to that DOM element or even to transform the DOM element and its children.

http://docs.angularjs.org/guide/services

AngularJS services are substitutable objects that are wired together using dependency injection (DI). You can use services to organize and share code across your app.