Add ol.geom.Circle

src/ol/geom/circle.exports

@@ -0,0 +1,11 @@
+@exportSymbol ol.geom.Circle
+@exportProperty ol.geom.Circle.prototype.clone
+@exportProperty ol.geom.Circle.prototype.getCenter
+@exportProperty ol.geom.Circle.prototype.getExtent
+@exportProperty ol.geom.Circle.prototype.getRadius
+@exportProperty ol.geom.Circle.prototype.getSimplifiedGeometry
+@exportProperty ol.geom.Circle.prototype.getType
+@exportProperty ol.geom.Circle.prototype.setCenter
+@exportProperty ol.geom.Circle.prototype.setCenterAndRadius
+@exportProperty ol.geom.Circle.prototype.setRadius
+@exportProperty ol.geom.Circle.prototype.transform

src/ol/geom/circle.js

@@ -0,0 +1,192 @@
+goog.provide('ol.geom.Circle');
+
+goog.require('goog.asserts');
+goog.require('ol.extent');
+goog.require('ol.geom.GeometryType');
+goog.require('ol.geom.SimpleGeometry');
+goog.require('ol.geom.flat');
+
+
+
+/**
+ * @constructor
+ * @extends {ol.geom.SimpleGeometry}
+ * @param {ol.geom.RawPoint} center Center.
+ * @param {number=} opt_radius Radius.
+ * @param {ol.geom.GeometryLayout=} opt_layout Layout.
+ */
+ol.geom.Circle = function(center, opt_radius, opt_layout) {
+  goog.base(this);
+  var radius = goog.isDef(opt_radius) ? opt_radius : 0;
+  this.setCenterAndRadius(center, radius, opt_layout);
+};
+goog.inherits(ol.geom.Circle, ol.geom.SimpleGeometry);
+
+
+/**
+ * @inheritDoc
+ */
+ol.geom.Circle.prototype.clone = function() {
+  var circle = new ol.geom.Circle(null);
+  circle.setFlatCoordinates(this.layout, this.flatCoordinates.slice());
+  return circle;
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.geom.Circle.prototype.closestPointXY =
+    function(x, y, closestPoint, minSquaredDistance) {
+  var flatCoordinates = this.flatCoordinates;
+  var radius = flatCoordinates[this.stride] - flatCoordinates[0];
+  var dx = x - flatCoordinates[0];
+  var dy = y - flatCoordinates[1];
+  var distance = Math.max(Math.sqrt(dx * dx + dy * dy) - radius, 0);
+  var squaredDistance = distance * distance;
+  if (squaredDistance < minSquaredDistance) {
+    // FIXME it must be possible to do this without trigonometric functions
+    var theta = Math.atan2(dy, dx);
+    closestPoint[0] = flatCoordinates[0] + radius * Math.cos(theta);
+    closestPoint[1] = flatCoordinates[1] + radius * Math.sin(theta);
+    return squaredDistance;
+  } else {
+    return minSquaredDistance;
+  }
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.geom.Circle.prototype.containsXY = function(x, y) {
+  var flatCoordinates = this.flatCoordinates;
+  var dx = x - flatCoordinates[0];
+  var dy = y - flatCoordinates[1];
+  var r = flatCoordinates[this.stride] - flatCoordinates[0];
+  return dx * dx + dy * dy <= r;
+};
+
+
+/**
+ * @return {ol.geom.RawPoint} Center.
+ */
+ol.geom.Circle.prototype.getCenter = function() {
+  return this.flatCoordinates.slice(0, this.stride);
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.geom.Circle.prototype.getExtent = function(opt_extent) {
+  if (this.extentRevision != this.revision) {
+    var flatCoordinates = this.flatCoordinates;
+    var radius = flatCoordinates[this.stride] - flatCoordinates[0];
+    this.extent = ol.extent.createOrUpdate(
+        flatCoordinates[0] - radius, flatCoordinates[1] - radius,
+        flatCoordinates[0] + radius, flatCoordinates[1] + radius,
+        this.extent);
+    this.extentRevision = this.revision;
+  }
+  goog.asserts.assert(goog.isDef(this.extent));
+  return ol.extent.returnOrUpdate(this.extent, opt_extent);
+};
+
+
+/**
+ * @return {number} Radius.
+ */
+ol.geom.Circle.prototype.getRadius = function() {
+  var dx = this.flatCoordinates[this.stride] - this.flatCoordinates[0];
+  var dy = this.flatCoordinates[this.stride + 1] - this.flatCoordinates[1];
+  return Math.sqrt(dx * dx + dy * dy);
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.geom.Circle.prototype.getSimplifiedGeometry = function(squaredTolerance) {
+  return this;
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.geom.Circle.prototype.getType = function() {
+  return ol.geom.GeometryType.CIRCLE;
+};
+
+
+/**
+ * @param {ol.geom.RawPoint} center Center.
+ */
+ol.geom.Circle.prototype.setCenter = function(center) {
+  var stride = this.stride;
+  goog.asserts.assert(center.length == stride);
+  var radius = this.flatCoordinates[stride] - this.flatCoordinates[0];
+  var flatCoordinates = center.slice();
+  flatCoordinates[stride] = flatCoordinates[0] + radius;
+  var i;
+  for (i = 1; i < stride; ++i) {
+    flatCoordinates[stride + i] = center[i];
+  }
+  this.setFlatCoordinates(this.layout, flatCoordinates);
+};
+
+
+/**
+ * @param {ol.geom.RawPoint} center Center.
+ * @param {number} radius Radius.
+ * @param {ol.geom.GeometryLayout=} opt_layout Layout.
+ */
+ol.geom.Circle.prototype.setCenterAndRadius =
+    function(center, radius, opt_layout) {
+  if (goog.isNull(center)) {
+    this.setFlatCoordinates(ol.geom.GeometryLayout.XY, null);
+  } else {
+    this.setLayout(opt_layout, center, 0);
+    if (goog.isNull(this.flatCoordinates)) {
+      this.flatCoordinates = [];
+    }
+    var flatCoordinates = this.flatCoordinates;
+    var offset = ol.geom.flat.deflateCoordinate(
+        flatCoordinates, 0, center, this.stride);
+    flatCoordinates[offset++] = flatCoordinates[0] + radius;
+    var i, ii;
+    for (i = 1, ii = this.stride; i < ii; ++i) {
+      flatCoordinates[offset++] = flatCoordinates[i];
+    }
+    flatCoordinates.length = offset;
+    this.dispatchChangeEvent();
+  }
+};
+
+
+/**
+ * @param {ol.geom.GeometryLayout} layout Layout.
+ * @param {Array.<number>} flatCoordinates Flat coordinates.
+ */
+ol.geom.Circle.prototype.setFlatCoordinates =
+    function(layout, flatCoordinates) {
+  this.setFlatCoordinatesInternal(layout, flatCoordinates);
+  this.dispatchChangeEvent();
+};
+
+
+/**
+ * @param {number} radius Radius.
+ */
+ol.geom.Circle.prototype.setRadius = function(radius) {
+  goog.asserts.assert(!goog.isNull(this.flatCoordinates));
+  this.flatCoordinates[this.stride] = this.flatCoordinates[0] + radius;
+  this.dispatchChangeEvent();
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.geom.Circle.prototype.transform = goog.abstractMethod;

src/ol/geom/geometry.js

@@ -18,7 +18,8 @@ ol.geom.GeometryType = {
   MULTI_POINT: 'MultiPoint',
   MULTI_LINE_STRING: 'MultiLineString',
   MULTI_POLYGON: 'MultiPolygon',
-  GEOMETRY_COLLECTION: 'GeometryCollection'
+  GEOMETRY_COLLECTION: 'GeometryCollection',
+  CIRCLE: 'Circle'
 };
 
 

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

@@ -0,0 +1,192 @@
+goog.provide('ol.test.geom.Circle');
+
+
+describe('ol.geom.Circle', function() {
+
+  describe('with a unit circle', function() {
+
+    var circle;
+    beforeEach(function() {
+      circle = new ol.geom.Circle([0, 0], 1);
+    });
+
+    describe('#clone', function() {
+
+      it('returns a clone', function() {
+        var clone = circle.clone();
+        expect(clone).to.be.an(ol.geom.Circle);
+        expect(clone.getCenter()).to.eql(circle.getCenter());
+        expect(clone.getCenter()).not.to.be(circle.getCenter());
+        expect(clone.getRadius()).to.be(circle.getRadius());
+      });
+
+    });
+
+    describe('#containsCoordinate', function() {
+
+      it('contains the center', function() {
+        expect(circle.containsCoordinate([0, 0])).to.be(true);
+      });
+
+      it('contains points inside the perimeter', function() {
+        expect(circle.containsCoordinate([0.5, 0.5])).to.be(true);
+        expect(circle.containsCoordinate([-0.5, 0.5])).to.be(true);
+        expect(circle.containsCoordinate([-0.5, -0.5])).to.be(true);
+        expect(circle.containsCoordinate([0.5, -0.5])).to.be(true);
+      });
+
+      it('contains points on the perimeter', function() {
+        expect(circle.containsCoordinate([1, 0])).to.be(true);
+        expect(circle.containsCoordinate([0, 1])).to.be(true);
+        expect(circle.containsCoordinate([-1, 0])).to.be(true);
+        expect(circle.containsCoordinate([0, -1])).to.be(true);
+      });
+
+      it('does not contain points outside the perimeter', function() {
+        expect(circle.containsCoordinate([2, 0])).to.be(false);
+        expect(circle.containsCoordinate([1, 1])).to.be(false);
+        expect(circle.containsCoordinate([-2, 0])).to.be(false);
+        expect(circle.containsCoordinate([0, -2])).to.be(false);
+      });
+
+    });
+
+    describe('#getCenter', function() {
+
+      it('returns the expected value', function() {
+        expect(circle.getCenter()).to.eql([0, 0]);
+      });
+
+    });
+
+    describe('#getClosestPoint', function() {
+
+      it('returns the closest point on the perimeter', function() {
+        var closestPoint;
+        closestPoint = circle.getClosestPoint([2, 0]);
+        expect(closestPoint[0]).to.roughlyEqual(1, 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(0, 1e-15);
+        closestPoint = circle.getClosestPoint([2, 2]);
+        expect(closestPoint[0]).to.roughlyEqual(Math.sqrt(0.5), 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(Math.sqrt(0.5), 1e-15);
+        closestPoint = circle.getClosestPoint([0, 2]);
+        expect(closestPoint[0]).to.roughlyEqual(0, 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(1, 1e-15);
+        closestPoint = circle.getClosestPoint([-2, 2]);
+        expect(closestPoint[0]).to.roughlyEqual(-Math.sqrt(0.5), 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(Math.sqrt(0.5), 1e-15);
+        closestPoint = circle.getClosestPoint([-2, 0]);
+        expect(closestPoint[0]).to.roughlyEqual(-1, 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(0, 1e-15);
+        closestPoint = circle.getClosestPoint([-2, -2]);
+        expect(closestPoint[0]).to.roughlyEqual(-Math.sqrt(0.5), 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(-Math.sqrt(0.5), 1e-15);
+        closestPoint = circle.getClosestPoint([0, -2]);
+        expect(closestPoint[0]).to.roughlyEqual(0, 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(-1, 1e-15);
+        closestPoint = circle.getClosestPoint([2, -2]);
+        expect(closestPoint[0]).to.roughlyEqual(Math.sqrt(0.5), 1e-15);
+        expect(closestPoint[1]).to.roughlyEqual(-Math.sqrt(0.5), 1e-15);
+      });
+
+    });
+
+    describe('#getExtent', function() {
+
+      it('returns the expected value', function() {
+        expect(circle.getExtent()).to.eql([-1, -1, 1, 1]);
+      });
+
+    });
+
+    describe('#getRadius', function() {
+
+      it('returns the expected value', function() {
+        expect(circle.getRadius()).to.be(1);
+      });
+
+    });
+
+    describe('#getSimplifiedGeometry', function() {
+
+      it('returns the same geometry', function() {
+        expect(circle.getSimplifiedGeometry(1)).to.be(circle);
+      });
+
+    });
+
+    describe('#getType', function() {
+
+      it('returns the expected value', function() {
+        expect(circle.getType()).to.be(ol.geom.GeometryType.CIRCLE);
+      });
+
+    });
+
+    describe('#setCenter', function() {
+
+      it('sets the center', function() {
+        circle.setCenter([1, 2]);
+        expect(circle.getCenter()).to.eql([1, 2]);
+      });
+
+      it('fires a change event', function() {
+        var spy = sinon.spy();
+        circle.on('change', spy);
+        circle.setCenter([1, 2]);
+        expect(spy.calledOnce).to.be(true);
+      });
+
+    });
+
+    describe('#setFlatCoordinates', function() {
+
+      it('sets both center and radius', function() {
+        circle.setFlatCoordinates(ol.geom.GeometryLayout.XY, [1, 2, 4, 2]);
+        expect(circle.getCenter()).to.eql([1, 2]);
+        expect(circle.getRadius()).to.be(3);
+      });
+
+      it('fires a single change event', function() {
+        var spy = sinon.spy();
+        circle.on('change', spy);
+        circle.setFlatCoordinates(ol.geom.GeometryLayout.XY, [1, 2, 4, 2]);
+        expect(spy.calledOnce).to.be(true);
+      });
+
+    });
+
+    describe('#setRadius', function() {
+
+      it('sets the radius', function() {
+        circle.setRadius(2);
+        expect(circle.getRadius()).to.be(2);
+      });
+
+      it('fires a change event', function() {
+        var spy = sinon.spy();
+        circle.on('change', spy);
+        circle.setRadius(2);
+        expect(spy.calledOnce).to.be(true);
+      });
+
+    });
+
+    describe('#transform', function() {
+
+      it('throws an exception', function() {
+        expect(function() {
+          circle.transform(ol.proj.identityTransform);
+        }).to.throwException();
+      });
+
+    });
+
+  });
+
+});
+
+
+goog.require('ol.geom.Circle');
+goog.require('ol.geom.GeometryType');
+goog.require('ol.proj');