dojo.require("esri.geometry.Circle");
Description
(Added at v3.8)
A circle (
Polygon
) created by a specified center point. This point can be provided as an
esri/geometry/Point
object or an array of latitude/longitude values.
Samples
Search for
samples that use this class.
Class hierarchy
esri/geometry.Geometry
|_esri/geometry.Polygon
|_esri/geometry.Circle
Constructors
new esri.geometry.Circle(center, options?) | Create a new Circle by specifying an input center location using either an esri.geometry.Point object or a latitude/longitude array and an object with the following optional properties: radius, radiusUnits, geodesic and numberOfPoints. |
new esri.geometry.Circle(params) | Create a new Circle by specifying an object with a required center location, defined as a longitude/latitude array or an esri.geometry.Point, and the following additional optional parameters: radius, radiusUnits, geodesic, and numberOfPoints. |
Properties
Methods
Constructor Details
Create a new Circle by specifying an input center location using either an esri.geometry.Point object or a latitude/longitude array and an object with the following optional properties: radius, radiusUnits, geodesic and numberOfPoints. See the options table for additional details.
Parameters:
<Point | Number[] > center |
Required |
Center point of the circle. It could be a esri.geometry.Point, or an array with value [longitude, latitude]. |
<Object > options |
Optional |
See options descriptions for further information. |
options
properties:
<Boolean > geodesic |
Optional |
Applicable when the spatial reference of the center point is either set to Web Mercator or geographic/geodesic as true would apply. Other coordinate systems will not create geodesic circles. By default, the value is false. |
<Number > numberOfPoints |
Optional |
A circle can be thought of similar to a polygon. This value controls how many points along the curve of the circle. If nothing is specified, the default value is 60. |
<Number > radius |
Optional |
Radius of the circle. If nothing specified, defaults to 1000. |
<String > radiusUnit |
Optional |
Unit of the radius. For example, a linear unit, such as METERS, MILES and so on, or an angular unit, such as DECIMAL_DEGREES. When the option geodesic is true, it must be a linear unit. The default value is esri.Units.METERS. |
Sample: - This example shows how to create a Circle
with an optional radius of 2000 meters with the required center location using lon/lat
var circleGeometry = new esri.geometry.Circle([-117.15, 32.71],{
radius: 2000
});
- This example shows how to create a Circle
with an optional radius of 2000 meters with the required center location using a provided
esri.geometry.Point
var point = new Point([-117.15,32.71]);
var circleGeometry = new esri.geometry.Circle(point,{radius:2000});
Create a new Circle by specifying an object with a required center location, defined as a longitude/latitude array or an esri.geometry.Point, and the following additional optional parameters: radius, radiusUnits, geodesic, and numberOfPoints. See the options table for additional details on the optional parameters.
Parameters:
<Object > params |
Required |
If no center parameter is provided, it must be set within the options. See options descriptions for further information. |
params
properties:
<Point | Number[] > center |
Required |
The center point of the circle. This option must be specified by either passing in an already defined esri.geometry.Point object or an array of longitude/latitude values. |
<Boolean > geodesic |
Optional |
Applicable when the spatial reference of the center point is either set to Web Mercator or geographic/geodesic as true would apply. Other coordinate systems will not create geodesic circles. By default, the value is false. |
<Number > numberOfPoints |
Optional |
A circle can be thought of similar to a polygon. This value controls how many points along the curve of the circle. If nothing is specified, the default value is 60. |
<Number > radius |
Optional |
The radius of the circle. It nothing specified, defaults to 1000. |
<String > radiusUnit |
Optional |
Unit of the radius. For example, a linear unit, such as METERS, MILES and so on, or an angular unit, such as DECIMAL_DEGREES. When the option geodesic is true, it must be a linear unit. The default value is esri.Units.METERS. |
Sample: - This example shows how to create a Circle
by specifying an object with a center location using long/lat and a radius of 100 miles
var circleGeometry = new esri.geometry.Circle({center:[-117.15, 32.71],
radius: 100,
radiusUnit:units.MILES
});
- This example shows how to create a Circle
by specifying an object with a center location using an esri.geometry.Point and a radius of 100 miles
var point = new Point([-117.15,32.71]);
var circleGeometry = new esri.geometry.Circle({center:point,
radius:100,
radiusUnit:Units.MILES});
Property Details
The cache is used to store values computed from geometries that need to cleared or recomputed upon mutation. An example is the extent of a polygon. The default value is undefined
. (Added at v3.13)
Default value: undefined
Center point of the circle. This center must be specified either as an esri.geometry.Point object or an array of longitude/latitude.
The radius of the circle based.
Default value: 1000
Unit of the radius. For example, a linear unit, such as METERS, MILES and so on, or an angular unit, such as DECIMAL_DEGREES. See
Units for a list of valid values. When the option geodesic is true, it must be a linear unit.
Default value: METERS
Array of coordinate values constituting the circle like [[x1, y1], [x2, y2],...]. The circle only has one ring, which is the circle curve. Specify the rings coordinate values for the circle's curve.
The spatial reference of the circle will be the same as the spatial reference of the center point.
The type of geometry.
Known values: point
| multipoint
| polyline
| polygon
| extent
Method Details
Adds a ring to the Polygon. The ring can be one of the following: an array of numbers or an array of points. When added the index of the ring is incremented by one.
Sample:
var polygon = new esri.geometry.Polygon(new esri.SpatialReference({wkid:4326}));
polygon.addRing([[-180,-90],[-180,90],[180,90],[180,-90],[-180,-90]]);
add points counter-clockwise to create a hole
polygon.addRing([[-83,35],[-74,35],[-74,41],[-83,41],[-83,35]]);
Sets the cache property to undefined
. (Added at v3.13)
Checks on the client if the specified point is inside the polygon. A point on the polygon line is considered in.
Parameters:
<Point > point |
Required |
The location defined by an X- and Y- coordinate in map units. |
Returns the value for a named property stored in the cache. (Added at v3.13)
Parameters:
<String > name |
Required |
The property name of the value to retrieve from the cache. |
Returns the centroid of the polygon as defined
here. For a polygon with multiple rings, returns the centroid of the largest ring.
Note: Polygon with holes supported as of version 3.8. (Added at v3.7)
Returns the extent of the polygon.
Sample:
var taxLotExtent = selectedTaxLot.geometry.getExtent();
Returns a point specified by a ring and point in the path.
Parameters:
<Number > ringIndex |
Required |
The index of a ring. |
<Number > pointIndex |
Required |
The index of a point in a ring. |
Inserts a new point into a polygon. (Added at v1.4)
Parameters:
<Number > ringIndex |
Required |
Ring index to insert point. |
<Number > pointIndex |
Required |
The index of the inserted point in the ring. |
<Point > point |
Required |
Point to insert into the ring. |
Checks if a
Polygon ring is clockwise. Returns true for clockwise and false for counterclockwise.
Sample: var clockwise = esri.geometry.isClockwise(polygon.rings[0]);
When true, the polygon is self-intersecting which means that the ring of the polygon crosses itself. Also checks to see if polygon rings cross each other. (Added at v2.2)
Parameters:
<Polygon > polygon |
Required |
The polygon to test for self-intersection. |
Sample: var isIntersecting = new esri.geometry.polygonSelfIntersecting(polygon);
Remove a point from the polygon at the given pointIndex within the ring identified by ringIndex. (Added at v2.0)
Parameters:
<Number > ringIndex |
Required |
The index of the ring containing the point. |
<Number > pointIndex |
Required |
The index of the point within the ring. |
Removes a ring from the Polygon. The index specifies which ring to remove.
Parameters:
<Number > ringIndex |
Required |
The index of the ring to remove. |
Sets the value for a named property stored in the cache. (Added at v3.13)
Parameters:
<String > name |
Required |
The property name for the value Object to store in the cache. |
<Object > value |
Required |
The value Object for a named property to store in the cache. |
Updates a point in a polygon. (Added at v1.4)
Parameters:
<Number > ringIndex |
Required |
Ring index for updated point. |
<Number > pointIndex |
Required |
The index of the updated point in the ring. |
<Point > point |
Required |
Point to update in the ring. |
Sets the spatial reference.