Allow access to right-hand oriented polygon coordinates

src/ol/geom/polygon.js

@@ -151,12 +151,30 @@ ol.geom.Polygon.prototype.getArea = function() {
 
 
 /**
+ * Get the coordinate array for this geometry.  This array has the structure
+ * of a GeoJSON coordinate array for polygons.
+ *
+ * @param {boolean=} opt_right Orient coordinates according to the right-hand
+ *     rule (counter-clockwise for exterior and clockwise for interior rings).
+ *     If `false`, coordinates will be oriented according to the left-hand rule
+ *     (clockwise for exterior and counter-clockwise for interior rings).
+ *     By default, coordinate orientation will depend on how the geometry was
+ *     constructed.
  * @return {Array.<Array.<ol.Coordinate>>} Coordinates.
  * @api stable
  */
-ol.geom.Polygon.prototype.getCoordinates = function() {
+ol.geom.Polygon.prototype.getCoordinates = function(opt_right) {
+  var flatCoordinates;
+  if (goog.isDef(opt_right)) {
+    flatCoordinates = this.getOrientedFlatCoordinates().slice();
+    ol.geom.flat.orient.orientLinearRings(
+        flatCoordinates, 0, this.ends_, this.stride, opt_right);
+  } else {
+    flatCoordinates = this.flatCoordinates;
+  }
+
   return ol.geom.flat.inflate.coordinatess(
-      this.flatCoordinates, 0, this.ends_, this.stride);
+      flatCoordinates, 0, this.ends_, this.stride);
 };
 
 

test/spec/ol/geom/polygon.test.js

@@ -120,6 +120,30 @@ describe('ol.geom.Polygon', function() {
       expect(polygon.containsCoordinate(insideInner)).to.be(false);
     });
 
+    describe('#getCoordinates()', function() {
+
+      var cw = [[-180, -90], [-180, 90], [180, 90], [180, -90], [-180, -90]];
+      var ccw = [[-180, -90], [180, -90], [180, 90], [-180, 90], [-180, -90]];
+      var right = new ol.geom.Polygon([ccw, cw]);
+      var left = new ol.geom.Polygon([cw, ccw]);
+
+      it('returns coordinates as they were constructed', function() {
+        expect(right.getCoordinates()).to.eql([ccw, cw]);
+        expect(left.getCoordinates()).to.eql([cw, ccw]);
+      });
+
+      it('can return coordinates with right-hand orientation', function() {
+        expect(right.getCoordinates(true)).to.eql([ccw, cw]);
+        expect(left.getCoordinates(true)).to.eql([ccw, cw]);
+      });
+
+      it('can return coordinates with left-hand orientation', function() {
+        expect(right.getCoordinates(false)).to.eql([cw, ccw]);
+        expect(left.getCoordinates(false)).to.eql([cw, ccw]);
+      });
+
+    });
+
     describe('#getOrientedFlatCoordinates', function() {
 
       it('reverses the outer ring if necessary', function() {