Merge pull request #2019 from fredj/device-orientation-example

Add an extent constraint to the device-orientation example

examples/device-orientation.js

@@ -3,10 +3,14 @@ goog.require('ol.Map');
 goog.require('ol.View2D');
 goog.require('ol.dom.Input');
 goog.require('ol.layer.Tile');
+goog.require('ol.proj');
 goog.require('ol.source.OSM');
 
+var projection = ol.proj.get('EPSG:3857');
 var view = new ol.View2D({
   center: [0, 0],
+  projection: projection,
+  extent: projection.getExtent(),
   zoom: 2
 });
 var map = new ol.Map({
@@ -41,5 +45,5 @@ deviceOrientation.on(['change:beta', 'change:gamma'], function(event) {
   center[0] -= resolution * gamma * 25;
   center[1] += resolution * beta * 25;
 
-  view.setCenter(center);
+  view.setCenter(view.constrainCenter(center));
 });

src/ol/view2d.js

@@ -59,14 +59,13 @@ ol.View2DProperty = {
  * that is passed to a setter will effectively be the value set in the view,
  * and returned by the corresponding getter.
  *
- * But an `ol.View2D` object also has a *resolution constraint* and a
- * *rotation constraint*. There's currently no *center constraint*, but
- * this may change in the future.
+ * But an `ol.View2D` object also has a *resolution constraint*, a
+ * *rotation constraint* and a *center constraint*.
  *
  * As said above no constraints are applied when the setters are used to set
  * new states for the view. Applying constraints is done explicitly through
  * the use of the `constrain*` functions (`constrainResolution` and
- * `constrainRotation`).
+ * `constrainRotation` and `constrainCenter`).
  *
  * The main users of the constraints are the interactions and the
  * controls. For example, double-clicking on the map changes the view to
@@ -184,8 +183,10 @@ ol.View2D.prototype.calculateCenterZoom = function(resolution, anchor) {
 
 
 /**
+ * Get the constrained center of this view.
  * @param {ol.Coordinate|undefined} center Center.
  * @return {ol.Coordinate|undefined} Constrained center.
+ * @todo api
  */
 ol.View2D.prototype.constrainCenter = function(center) {
   return this.constraints_.center(center);
@@ -193,7 +194,7 @@ ol.View2D.prototype.constrainCenter = function(center) {
 
 
 /**
- * Get the constrained the resolution of this view.
+ * Get the constrained resolution of this view.
  * @param {number|undefined} resolution Resolution.
  * @param {number=} opt_delta Delta. Default is `0`.
  * @param {number=} opt_direction Direction. Default is `0`.