OpenLayers v4.0.1 API - Class: Circle

# Class: Circle

This documentation is for OpenLayers v4.0.1. The latest is v.

## ol.geom.Circle

Circle geometry.

#### new ol.geom.Circle(center, opt_radius, opt_layout)

src/ol/geom/circle.js, line 22

  Name | Type | Description
  --- | --- | ---
  `center` | ol.Coordinate | Center.
  `radius` | number | Radius.
  `layout` | ol.geom.GeometryLayout | Layout.

  ##### Fires:

  - `change` (ol.events.Event) - Generic change event. Triggered when the revision counter is increased.
  - `propertychange` (ol.Object.Event) - Triggered when a property is changed.

### Extends

- ol.geom.SimpleGeometry

### Methods

#### applyTransform(transformFn) inherited

src/ol/geom/simplegeometry.js, line 256

  Apply a transform function to each coordinate of the geometry. The geometry is modified in place. If you do not want the geometry modified in place, first `clone()` it and then use this function on the clone.

  Name | Type | Description
  --- | --- | ---
  `transformFn` | ol.TransformFunction | Transform.

#### changed() inherited

src/ol/observable.js, line 58

  Increases the revision counter and dispatches a 'change' event.

#### clone(){ol.geom.Circle}

src/ol/geom/circle.js, line 36

  Make a complete copy of the geometry.

  ##### Returns:

  Clone.

#### dispatchEvent(event) inherited

src/ol/observable.js, line 75

  Dispatches an event and calls all listeners listening for events of this type. The event parameter can either be a string or an Object with a `type` property.

  Name | Type | Description
  --- | --- | ---
  `event` | Object | ol.events.Event | string | Event object.

#### get(key){*} inherited

src/ol/object.js, line 101

  Gets a value.

  Name | Type | Description
  --- | --- | ---
  `key` | string | Key name.

  ##### Returns:

  Value.

#### getCenter(){ol.Coordinate}

src/ol/geom/circle.js, line 89

  Return the center of the circle as `coordinate`.

  ##### Returns:

  Center.

#### getClosestPoint(point, opt_closestPoint){ol.Coordinate} inherited

src/ol/geom/geometry.js, line 89

  Return the closest point of the geometry to the passed point as `coordinate`.

  Name | Type | Description
  --- | --- | ---
  `point` | ol.Coordinate | Point.
  `closestPoint` | ol.Coordinate | Closest point.

  ##### Returns:

  Closest point.

#### getExtent(opt_extent){ol.Extent} inherited

src/ol/geom/geometry.js, line 131

  Get the extent of the geometry.

  Name | Type | Description
  --- | --- | ---
  `extent` | ol.Extent | Extent.

  ##### Returns:

  extent Extent.

#### getFirstCoordinate(){ol.Coordinate} inherited

src/ol/geom/simplegeometry.js, line 111

  Return the first coordinate of the geometry.

  ##### Returns:

  First coordinate.

#### getKeys(){Array.<string>} inherited

src/ol/object.js, line 115

  Get a list of object property names.

  ##### Returns:

  List of property names.

#### getLastCoordinate(){ol.Coordinate} inherited

src/ol/geom/simplegeometry.js, line 129

  Return the last coordinate of the geometry.

  ##### Returns:

  Last point.

#### getLayout(){ol.geom.GeometryLayout} inherited

src/ol/geom/simplegeometry.js, line 139

  Return the `layout` of the geometry.

  ##### Returns:

  Layout.

#### getProperties(){Object.<string, *>} inherited

src/ol/object.js, line 125

  Get an object of all property names and values.

  ##### Returns:

  Object.

#### getRadius(){number}

src/ol/geom/circle.js, line 112

  Return the radius of the circle.

  ##### Returns:

  Radius.

#### getRevision(){number} inherited

src/ol/observable.js, line 84

  Get the version number for this object. Each time the object is modified, its version number will be incremented.

  ##### Returns:

  Revision.

#### getType(){ol.geom.GeometryType}

src/ol/geom/circle.js, line 132

  Get the type of this geometry.

  ##### Returns:

  Geometry type.

#### intersectsCoordinate(coordinate){boolean} inherited

src/ol/geom/geometry.js, line 103

  Returns true if this geometry includes the specified coordinate. If the coordinate is on the boundary of the geometry, returns false.

  Name | Type | Description
  --- | --- | ---
  `coordinate` | ol.Coordinate | Coordinate.

  ##### Returns:

  Contains coordinate.

#### intersectsExtent(extent){boolean}

src/ol/geom/circle.js, line 141

  Test if the geometry and the passed extent intersect.

  Name | Type | Description
  --- | --- | ---
  `extent` | ol.Extent | Extent.

  ##### Returns:

  `true` if the geometry and the extent intersect.

#### on(type, listener, opt_this){ol.EventsKey|Array.<ol.EventsKey>} inherited

src/ol/observable.js, line 99

  Listen for a certain type of event.

  Name | Type | Description
  --- | --- | ---
  `type` | string | Array.<string> | The event type or array of event types.
  `listener` | function | The listener function.
  `this` | Object | The object to use as `this` in `listener`.

  ##### Returns:

  Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.

#### once(type, listener, opt_this){ol.EventsKey|Array.<ol.EventsKey>} inherited

src/ol/observable.js, line 124

  Listen once for a certain type of event.

  Name | Type | Description
  --- | --- | ---
  `type` | string | Array.<string> | The event type or array of event types.
  `listener` | function | The listener function.
  `this` | Object | The object to use as `this` in `listener`.

  ##### Returns:

  Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.

#### rotate(angle, anchor) inherited

src/ol/geom/geometry.js, line 148

  Rotate the geometry around a given coordinate. This modifies the geometry coordinates in place.

  Name | Type | Description
  --- | --- | ---
  `angle` | number | Rotation angle in radians.
  `anchor` | ol.Coordinate | The rotation center.

#### scale(sx, opt_sy, opt_anchor) inherited

src/ol/geom/geometry.js, line 162

  Scale the geometry (with an optional origin). This modifies the geometry coordinates in place.

  Name | Type | Description
  --- | --- | ---
  `sx` | number | The scaling factor in the x-direction.
  `sy` | number | The scaling factor in the y-direction (defaults to sx).
  `anchor` | ol.Coordinate | The scale origin (defaults to the center of the geometry extent).

#### set(key, value, opt_silent) inherited

src/ol/object.js, line 150

  Sets a value.

  Name | Type | Description
  --- | --- | ---
  `key` | string | Key name.
  `value` | * | Value.
  `silent` | boolean | Update without triggering an event.

#### setCenter(center)

src/ol/geom/circle.js, line 165

  Set the center of the circle as `coordinate`.

  Name | Type | Description
  --- | --- | ---
  `center` | ol.Coordinate | Center.

#### setCenterAndRadius(center, radius, opt_layout)

src/ol/geom/circle.js, line 186

  Set the center (as `coordinate`) and the radius (as number) of the circle.

  Name | Type | Description
  --- | --- | ---
  `center` | ol.Coordinate | Center.
  `radius` | number | Radius.
  `layout` | ol.geom.GeometryLayout | Layout.

#### setProperties(values, opt_silent) inherited

src/ol/object.js, line 170

  Sets a collection of key-value pairs. Note that this changes any existing properties and adds new ones (it does not remove any existing properties).

  Name | Type | Description
  --- | --- | ---
  `values` | Object.<string, *> | Values.
  `silent` | boolean | Update without triggering an event.

#### setRadius(radius)

src/ol/geom/circle.js, line 236

  Set the radius of the circle. The radius is in the units of the projection.

  Name | Type | Description
  --- | --- | ---
  `radius` | number | Radius.

#### simplify(tolerance){ol.geom.Geometry} inherited

src/ol/geom/geometry.js, line 177

  Create a simplified version of this geometry. For linestrings, this uses the the Douglas Peucker algorithm. For polygons, a quantization-based simplification is used to preserve topology.

  Name | Type | Description
  --- | --- | ---
  `tolerance` | number | The tolerance distance for simplification.

  ##### Returns:

  A new, simplified version of the original geometry.

#### transform(source, destination){ol.geom.Circle}

src/ol/geom/circle.js, line 264

  Transform each coordinate of the circle from one coordinate reference system to another. The geometry is modified in place. If you do not want the geometry modified in place, first clone() it and then use this function on the clone.

  Internally a circle is currently represented by two points: the center of the circle `[cx, cy]`, and the point to the right of the circle `[cx + r, cy]`. This `transform` function just transforms these two points. So the resulting geometry is also a circle, and that circle does not correspond to the shape that would be obtained by transforming every point of the original circle.

  Name | Type | Description
  --- | --- | ---
  `source` | ol.ProjectionLike | The current projection. Can be a string identifier or a `ol.proj.Projection` object.
  `destination` | ol.ProjectionLike | The desired projection. Can be a string identifier or a `ol.proj.Projection` object.

  ##### Returns:

  This geometry. Note that original geometry is modified in place.

#### translate(deltaX, deltaY) inherited

src/ol/geom/simplegeometry.js, line 308

  Translate the geometry. This modifies the geometry coordinates in place. If instead you want a new geometry, first `clone()` this geometry.

  Name | Type | Description
  --- | --- | ---
  `deltaX` | number | Delta X.
  `deltaY` | number | Delta Y.

#### un(type, listener, opt_this) inherited

src/ol/observable.js, line 147

  Unlisten for a certain type of event.

  Name | Type | Description
  --- | --- | ---
  `type` | string | Array.<string> | The event type or array of event types.
  `listener` | function | The listener function.
  `this` | Object | The object which was used as `this` by the `listener`.

#### unset(key, opt_silent) inherited

src/ol/object.js, line 184

  Unsets a property.

  Name | Type | Description
  --- | --- | ---
  `key` | string | Key name.
  `silent` | boolean | Unset without triggering an event.