Snap — OpenLayers API reference

new Snap(options) interaction/Snap.js, line 324

Name	Type	Description
`features`	Collection<Feature> \| undefined	Snap to these features. Either this option or source should be provided.
`source`	VectorSource \| undefined	Snap to features from this source. Either this option or features should be provided
`edge`	boolean (defaults to true)	Snap to edges.
`vertex`	boolean (defaults to true)	Snap to vertices.
`intersection`	boolean (defaults to false)	Snap to intersections between segments.
`pixelTolerance`	number (defaults to 10)	Pixel tolerance for considering the pointer close enough to a segment or vertex for snapping.
`segmenters`	Segmenters \| undefined	Custom segmenters by `Type`. By default, the following segmenters are used: `Point`: A one-dimensional segment (e.g. `[[10, 20]]`) representing the point. `LineString`: One two-dimensional segment (e.g. `[[10, 20], [30, 40]]`) for each segment of the linestring. `Polygon`: One two-dimensional segment for each segment of the exterior ring and the interior rings. `Circle`: One two-dimensional segment for each segment of a regular polygon with 32 points representing the circle circumference. `GeometryCollection`: All segments of the contained geometries. `MultiPoint`: One one-dimensional segment for each point. `MultiLineString`: One two-dimensional segment for each segment of the linestrings. `MultiPolygon`: One two-dimensional segment for each segment of the polygons.

Fires:

change (BaseEvent) - Generic change event. Triggered when the revision counter is increased.
change:active (ObjectEvent)
error (BaseEvent) - Generic error event. Triggered when an error occurs.
propertychange (ObjectEvent) - Triggered when a property is changed.
snap (SnapEvent) - Triggered upon snapping to vertex or edge
unsnap (SnapEvent) - Triggered if no longer snapped

Extends

PointerInteraction

Observable Properties

Name	Type	Settable	ObjectEvent type	Description
`active`	boolean	yes	`change:active`	`true` if the interaction is active, `false` otherwise.

Methods

addFeature(feature, register) interaction/Snap.js, line 450

Add a feature to the collection of features that we may snap to.

Name	Type	Description
`feature`	Feature	Feature.
`register`	boolean \| undefined	Whether to listen to the feature change or not Defaults to `true`.

changed() inherited Observable.js, line 72

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

dispatchEvent(event){boolean | undefined} inherited events/Target.js, line 85

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`	BaseEvent \| string	Event object.

Returns:

false if anyone called preventDefault on the event object or if any of the listeners returned false.

get(key){*} inherited Object.js, line 136

Gets a value.

Name	Type	Description
`key`	string	Key name.

Returns:

Value.

getActive(){boolean} inherited interaction/Interaction.js, line 82

Return whether the interaction is currently active.

Returns:

true if the interaction is active, false otherwise.

getKeys(){Array.<string>} inherited Object.js, line 149

Get a list of object property names.

Returns:

List of property names.

getMap(){Map | null} inherited interaction/Interaction.js, line 91

Get the map associated with this interaction.

Returns:

Map.

getPointerCount(){number} inherited interaction/Pointer.js, line 95

Returns the current number of pointers involved in the interaction, e.g. 2 when two fingers are used.

Returns:

The number of pointers.

getProperties(){NoInfer.<Properties>} inherited Object.js, line 158

Get an object of all property names and values.

Returns:

Object.

getRevision(){number} inherited Observable.js, line 83

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

Returns:

Revision.

handleEvent(evt){boolean} interaction/Snap.js, line 585

Name	Type	Description
`evt`	MapBrowserEvent	Map browser event.

Returns:

false to stop event propagation.

on(type, listener){EventsKey | Array<EventsKey>} inherited Observable.js, line 156

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.

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){EventsKey | Array<EventsKey>} inherited Observable.js, line 168

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.

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.

removeFeature(feature, unlisten) interaction/Snap.js, line 697

Remove a feature from the collection of features that we may snap to.

Name	Type	Description
`feature`	Feature	Feature
`unlisten`	boolean \| undefined	Whether to unlisten to the feature change or not. Defaults to `true`.

set(key, value, silent) inherited Object.js, line 218

Sets a value.

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

setActive(active) inherited interaction/Interaction.js, line 111

Activate or deactivate the interaction.

Name	Type	Description
`active`	boolean	Active.

setProperties(values, silent) inherited Object.js, line 241

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`	Partial.<NoInfer.<Properties>>	Values.
`silent`	boolean \| undefined	Update without triggering an event.

un(type, listener) inherited Observable.js, line 177

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.

unset(key, silent) inherited Object.js, line 265

Unsets a property.

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