Merge pull request #2036 from tschaub/transform

More convenient geometry transforms.

examples/tissot.js

@@ -1,6 +1,7 @@
 goog.require('ol.Feature');
 goog.require('ol.Map');
 goog.require('ol.View2D');
+goog.require('ol.geom.Polygon');
 goog.require('ol.layer.Tile');
 goog.require('ol.layer.Vector');
 goog.require('ol.source.TileWMS');
@@ -38,7 +39,7 @@ var map = new ol.Map({
 var radius = 800000;
 for (var x = -180; x < 180; x += 30) {
   for (var y = -90; y < 90; y += 30) {
-    var geometry = ol.sphere.WGS84.circle([x, y], radius, 64);
-    vectorSource.addFeature(new ol.Feature(geometry));
+    var circle = ol.geom.Polygon.circular(ol.sphere.WGS84, [x, y], radius, 64);
+    vectorSource.addFeature(new ol.Feature(circle));
   }
 }

src/ol/extent.js

@@ -714,13 +714,15 @@ ol.extent.touches = function(extent1, extent2) {
 
 
 /**
+ * Apply a transform function to the extent.
  * @param {ol.Extent} extent Extent.
- * @param {ol.TransformFunction} transformFn Transform function.
+ * @param {ol.TransformFunction} transformFn Transform function.  Called with
+ * [minX, minY, maxX, maxY] extent coordinates.
  * @param {ol.Extent=} opt_extent Destination extent.
  * @return {ol.Extent} Extent.
  * @todo api
  */
-ol.extent.transform = function(extent, transformFn, opt_extent) {
+ol.extent.applyTransform = function(extent, transformFn, opt_extent) {
   var coordinates = [
     extent[0], extent[1],
     extent[0], extent[3],

src/ol/geolocation.js

@@ -11,6 +11,7 @@ goog.require('ol.BrowserFeature');
 goog.require('ol.Coordinate');
 goog.require('ol.Object');
 goog.require('ol.geom.Geometry');
+goog.require('ol.geom.Polygon');
 goog.require('ol.proj');
 goog.require('ol.sphere.WGS84');
 
@@ -186,8 +187,9 @@ ol.Geolocation.prototype.positionChange_ = function(position) {
   this.set(ol.GeolocationProperty.POSITION, projectedPosition);
   this.set(ol.GeolocationProperty.SPEED,
       goog.isNull(coords.speed) ? undefined : coords.speed);
-  var geometry = ol.sphere.WGS84.circle(this.position_, coords.accuracy);
-  geometry.transform(this.transform_);
+  var geometry = ol.geom.Polygon.circular(
+      ol.sphere.WGS84, this.position_, coords.accuracy);
+  geometry.applyTransform(this.transform_);
   this.set(ol.GeolocationProperty.ACCURACY_GEOMETRY, geometry);
   this.dispatchChangeEvent();
 };

src/ol/geom/circle.js

@@ -217,4 +217,4 @@ ol.geom.Circle.prototype.setRadius = function(radius) {
 /**
  * @inheritDoc
  */
-ol.geom.Circle.prototype.transform = goog.abstractMethod;
+ol.geom.Circle.prototype.applyTransform = goog.abstractMethod;

src/ol/geom/geometry.js

@@ -4,6 +4,7 @@ goog.provide('ol.geom.GeometryType');
 goog.require('goog.asserts');
 goog.require('goog.functions');
 goog.require('ol.Observable');
+goog.require('ol.proj');
 
 
 /**
@@ -159,10 +160,30 @@ ol.geom.Geometry.prototype.getType = goog.abstractMethod;
 
 
 /**
+ * Apply a transform function to the geometry.  Modifies the geometry in place.
  * @function
  * @param {ol.TransformFunction} transformFn Transform.
+ * @todo api
  */
-ol.geom.Geometry.prototype.transform = goog.abstractMethod;
+ol.geom.Geometry.prototype.applyTransform = goog.abstractMethod;
+
+
+/**
+ * Transform a geometry from one coordinate reference system to another.
+ * Modifies the geometry in place.
+ *
+ * @param {ol.proj.ProjectionLike} source The current projection.  Can be a
+ *     string identifier or a {@link ol.proj.Projection} object.
+ * @param {ol.proj.ProjectionLike} destination The desired projection.  Can be a
+ *     string identifier or a {@link ol.proj.Projection} object.
+ * @return {ol.geom.Geometry} This geometry.  Note that original geometry is
+ *     modified in place.
+ * @todo api
+ */
+ol.geom.Geometry.prototype.transform = function(source, destination) {
+  this.applyTransform(ol.proj.getTransform(source, destination));
+  return this;
+};
 
 
 /**

src/ol/geom/geometrycollection.js

@@ -247,11 +247,11 @@ ol.geom.GeometryCollection.prototype.setGeometriesArray = function(geometries) {
 /**
  * @inheritDoc
  */
-ol.geom.GeometryCollection.prototype.transform = function(transformFn) {
+ol.geom.GeometryCollection.prototype.applyTransform = function(transformFn) {
   var geometries = this.geometries_;
   var i, ii;
   for (i = 0, ii = geometries.length; i < ii; ++i) {
-    geometries[i].transform(transformFn);
+    geometries[i].applyTransform(transformFn);
   }
   this.dispatchChangeEvent();
 };

src/ol/geom/polygon.js

@@ -314,3 +314,29 @@ ol.geom.Polygon.prototype.setFlatCoordinates =
   this.ends_ = ends;
   this.dispatchChangeEvent();
 };
+
+
+/**
+ * Create an approximation of a circle on the surface of a sphere.
+ * @param {ol.Sphere} sphere The sphere.
+ * @param {ol.Coordinate} center Center.
+ * @param {number} radius Radius.
+ * @param {number=} opt_n Optional number of points.  Default is `32`.
+ * @return {ol.geom.Polygon} Circle geometry.
+ * @todo api
+ */
+ol.geom.Polygon.circular = function(sphere, center, radius, opt_n) {
+  var n = goog.isDef(opt_n) ? opt_n : 32;
+  /** @type {Array.<number>} */
+  var flatCoordinates = [];
+  var i;
+  for (i = 0; i < n; ++i) {
+    goog.array.extend(
+        flatCoordinates, sphere.offset(center, radius, 2 * Math.PI * i / n));
+  }
+  flatCoordinates.push(flatCoordinates[0], flatCoordinates[1]);
+  var polygon = new ol.geom.Polygon(null);
+  polygon.setFlatCoordinates(
+      ol.geom.GeometryLayout.XY, flatCoordinates, [flatCoordinates.length]);
+  return polygon;
+};

src/ol/geom/simplegeometry.js

@@ -242,9 +242,8 @@ ol.geom.SimpleGeometry.prototype.setLayout =
 
 /**
  * @inheritDoc
- * @todo api
  */
-ol.geom.SimpleGeometry.prototype.transform = function(transformFn) {
+ol.geom.SimpleGeometry.prototype.applyTransform = function(transformFn) {
   if (!goog.isNull(this.flatCoordinates)) {
     transformFn(this.flatCoordinates, this.flatCoordinates, this.stride);
     this.dispatchChangeEvent();

src/ol/interaction/draganddropinteraction.js

@@ -118,7 +118,7 @@ ol.interaction.DragAndDrop.prototype.handleResult_ = function(file, result) {
         var feature = readFeatures[j];
         var geometry = feature.getGeometry();
         if (!goog.isNull(geometry)) {
-          geometry.transform(transform);
+          geometry.applyTransform(transform);
         }
         features.push(feature);
       }

src/ol/source/bingmapssource.js

@@ -139,7 +139,8 @@ ol.source.BingMaps.prototype.handleImageryMetadataResponse =
                 var maxZ = coverageArea.zoomMax;
                 var bbox = coverageArea.bbox;
                 var epsg4326Extent = [bbox[1], bbox[0], bbox[3], bbox[2]];
-                var extent = ol.extent.transform(epsg4326Extent, transform);
+                var extent = ol.extent.applyTransform(
+                    epsg4326Extent, transform);
                 var tileRange, z, zKey;
                 for (z = minZ; z <= maxZ; ++z) {
                   zKey = z.toString();

src/ol/source/formatvectorsource.js

@@ -125,7 +125,7 @@ ol.source.FormatVector.prototype.readFeatures = function(source) {
         var feature = features[i];
         var geometry = feature.getGeometry();
         if (!goog.isNull(geometry)) {
-          geometry.transform(transform);
+          geometry.applyTransform(transform);
         }
       }
     }

src/ol/source/tilejsonsource.js

@@ -55,7 +55,7 @@ ol.source.TileJSON.prototype.handleTileJSONResponse = function(tileJSON) {
   if (goog.isDef(tileJSON.bounds)) {
     var transform = ol.proj.getTransformFromProjections(
         epsg4326Projection, this.getProjection());
-    extent = ol.extent.transform(tileJSON.bounds, transform);
+    extent = ol.extent.applyTransform(tileJSON.bounds, transform);
     this.setExtent(extent);
   }
 

src/ol/sphere/sphere.js

@@ -12,7 +12,6 @@ goog.provide('ol.Sphere');
 
 goog.require('goog.array');
 goog.require('goog.math');
-goog.require('ol.geom.Polygon');
 
 
 
@@ -30,33 +29,6 @@ ol.Sphere = function(radius) {
 };
 
 
-/**
- * Returns an approximation to a circle centered on `center` with radius
- * `radius` with `n` distinct points.
- *
- * @param {ol.Coordinate} center Center.
- * @param {number} radius Radius.
- * @param {number=} opt_n N.
- * @return {ol.geom.Geometry} Circle geometry.
- * @todo api
- */
-ol.Sphere.prototype.circle = function(center, radius, opt_n) {
-  var n = goog.isDef(opt_n) ? opt_n : 32;
-  /** @type {Array.<number>} */
-  var flatCoordinates = [];
-  var i;
-  for (i = 0; i < n; ++i) {
-    goog.array.extend(
-        flatCoordinates, this.offset(center, radius, 2 * Math.PI * i / n));
-  }
-  flatCoordinates.push(flatCoordinates[0], flatCoordinates[1]);
-  var polygon = new ol.geom.Polygon(null);
-  polygon.setFlatCoordinates(
-      ol.geom.GeometryLayout.XY, flatCoordinates, [flatCoordinates.length]);
-  return polygon;
-};
-
-
 /**
  * Returns the distance from c1 to c2 using the spherical law of cosines.
  *

test/spec/ol/extent.test.js

@@ -425,12 +425,13 @@ describe('ol.extent', function() {
 
   });
 
-  describe('transform', function() {
+  describe('#applyTransform()', function() {
 
     it('does transform', function() {
       var transformFn = ol.proj.getTransform('EPSG:4326', 'EPSG:3857');
       var sourceExtent = [-15, -30, 45, 60];
-      var destinationExtent = ol.extent.transform(sourceExtent, transformFn);
+      var destinationExtent = ol.extent.applyTransform(
+          sourceExtent, transformFn);
       expect(destinationExtent).not.to.be(undefined);
       expect(destinationExtent).not.to.be(null);
       // FIXME check values with third-party tool
@@ -456,7 +457,8 @@ describe('ol.extent', function() {
         return output;
       };
       var sourceExtent = [-15, -30, 45, 60];
-      var destinationExtent = ol.extent.transform(sourceExtent, transformFn);
+      var destinationExtent = ol.extent.applyTransform(
+          sourceExtent, transformFn);
       expect(destinationExtent).not.to.be(undefined);
       expect(destinationExtent).not.to.be(null);
       expect(destinationExtent[0]).to.be(-45);

test/spec/ol/geom/circle.test.js

@@ -207,7 +207,7 @@ describe('ol.geom.Circle', function() {
 
       it('throws an exception', function() {
         expect(function() {
-          circle.transform(ol.proj.identityTransform);
+          circle.applyTransform(ol.proj.identityTransform);
         }).to.throwException();
       });
 

test/spec/ol/geom/geometrycollection.test.js

@@ -139,6 +139,35 @@ describe('ol.geom.GeometryCollection', function() {
 
   });
 
+  describe('#transform()', function() {
+
+    var line, multi, point;
+    beforeEach(function() {
+      point = new ol.geom.Point([10, 20]);
+      line = new ol.geom.LineString([[10, 20], [30, 40]]);
+      multi = new ol.geom.GeometryCollection([point, line]);
+    });
+
+    it('transforms all geometries', function() {
+      multi.transform('EPSG:4326', 'EPSG:3857');
+
+      var geometries = multi.getGeometries();
+      expect(geometries[0]).to.be.a(ol.geom.Point);
+      expect(geometries[1]).to.be.a(ol.geom.LineString);
+
+      var coords = geometries[0].getCoordinates();
+      expect(coords[0]).to.roughlyEqual(1113194.90, 1e-2);
+      expect(coords[1]).to.roughlyEqual(2273030.92, 1e-2);
+
+      coords = geometries[1].getCoordinates();
+      expect(coords[0][0]).to.roughlyEqual(1113194.90, 1e-2);
+      expect(coords[0][1]).to.roughlyEqual(2273030.92, 1e-2);
+      expect(coords[1][0]).to.roughlyEqual(3339584.72, 1e-2);
+      expect(coords[1][1]).to.roughlyEqual(4865942.27, 1e-2);
+    });
+
+  });
+
 });
 
 

test/spec/ol/geom/multipoint.test.js

@@ -192,6 +192,63 @@ describe('ol.geom.MultiPoint', function() {
 
   });
 
+  describe('#applyTransform()', function() {
+
+    var multi, transform;
+    beforeEach(function() {
+      multi = new ol.geom.MultiPoint([[1, 2], [3, 4]]);
+      transform = sinon.spy();
+    });
+
+    it('calls a transform function', function() {
+      multi.applyTransform(transform);
+      expect(transform.calledOnce).to.be(true);
+      var args = transform.firstCall.args;
+      expect(args).to.have.length(3);
+
+      expect(args[0]).to.be(multi.getFlatCoordinates()); // input coords
+      expect(args[1]).to.be(multi.getFlatCoordinates()); // output coords
+      expect(args[2]).to.be(2); // dimension
+    });
+
+    it('allows for modification of coordinates', function() {
+      var mod = function(input, output, dimension) {
+        var copy = input.slice();
+        for (var i = 0, ii = copy.length; i < ii; i += dimension) {
+          output[i] = copy[i + 1];
+          output[i + 1] = copy[i];
+        }
+      };
+      multi.applyTransform(mod);
+      expect(multi.getCoordinates()).to.eql([[2, 1], [4, 3]]);
+    });
+
+    it('returns undefined', function() {
+      var got = multi.applyTransform(transform);
+      expect(got).to.be(undefined);
+    });
+
+  });
+
+  describe('#transform()', function() {
+
+    it('transforms a geometry given CRS identifiers', function() {
+      var multi = new ol.geom.MultiPoint([[-111, 45], [111, -45]]).transform(
+          'EPSG:4326', 'EPSG:3857');
+
+      expect(multi).to.be.a(ol.geom.MultiPoint);
+
+      var coords = multi.getCoordinates();
+
+      expect(coords[0][0]).to.roughlyEqual(-12356463.47, 1e-2);
+      expect(coords[0][1]).to.roughlyEqual(5621521.48, 1e-2);
+
+      expect(coords[1][0]).to.roughlyEqual(12356463.47, 1e-2);
+      expect(coords[1][1]).to.roughlyEqual(-5621521.48, 1e-2);
+    });
+
+  });
+
 });
 
 

test/spec/ol/geom/point.test.js

@@ -106,6 +106,67 @@ describe('ol.geom.Point', function() {
 
   });
 
+  describe('#applyTransform()', function() {
+
+    var point, transform;
+    beforeEach(function() {
+      point = new ol.geom.Point([1, 2]);
+      transform = sinon.spy();
+    });
+
+    it('calls a transform function', function() {
+      point.applyTransform(transform);
+      expect(transform.calledOnce).to.be(true);
+      var args = transform.firstCall.args;
+      expect(args).to.have.length(3);
+
+      expect(args[0]).to.be(point.getFlatCoordinates()); // input coords
+      expect(args[1]).to.be(point.getFlatCoordinates()); // output coords
+      expect(args[2]).to.be(2); // dimension
+    });
+
+    it('allows for modification of coordinates', function() {
+      var mod = function(input, output, dimension) {
+        var copy = input.slice();
+        output[1] = copy[0];
+        output[0] = copy[1];
+      };
+      point.applyTransform(mod);
+      expect(point.getCoordinates()).to.eql([2, 1]);
+    });
+
+    it('returns undefined', function() {
+      var got = point.applyTransform(transform);
+      expect(got).to.be(undefined);
+    });
+
+  });
+
+  describe('#transform()', function() {
+
+    it('transforms a geometry given CRS identifiers', function() {
+      var point = new ol.geom.Point([-111, 45]).transform(
+          'EPSG:4326', 'EPSG:3857');
+
+      expect(point).to.be.a(ol.geom.Point);
+
+      var coords = point.getCoordinates();
+
+      expect(coords[0]).to.roughlyEqual(-12356463.47, 1e-2);
+      expect(coords[1]).to.roughlyEqual(5621521.48, 1e-2);
+    });
+
+    it('modifies the original', function() {
+      var point = new ol.geom.Point([-111, 45]);
+      point.transform('EPSG:4326', 'EPSG:3857');
+      var coords = point.getCoordinates();
+
+      expect(coords[0]).to.roughlyEqual(-12356463.47, 1e-2);
+      expect(coords[1]).to.roughlyEqual(5621521.48, 1e-2);
+    });
+
+  });
+
 });