OpenLayers v5.3.0 API

Class: Snap

ol/interaction/Snap~Snap

import Snap from 'ol/interaction/Snap';

Handles snapping of vector features while modifying or drawing them. The features can come from a module:ol/source/Vector or module:ol/Collection~Collection Any interaction object that allows the user to interact with the features using the mouse can benefit from the snapping, as long as it is added before.

The snap interaction modifies map browser event coordinate and pixel properties to force the snap to occur to any interaction that them.

Example:

import Snap from 'ol/interaction/Snap';

var snap = new Snap({
  source: source
});

new Snap(opt_options)

interaction/Snap.js, line 79

Name Type Description

options

Options.

Name	Type	Default	Description
`features`	module:ol/Collection~Collection.<module:ol/Feature~Feature>		Snap to these features. Either this option or source should be provided.
`edge`	boolean	true	Snap to edges.
`vertex`	boolean	true	Snap to vertices.
`pixelTolerance`	number	10	Pixel tolerance for considering the pointer close enough to a segment or vertex for snapping.
`source`	module:ol/source/Vector~VectorSource		Snap to features from this source. Either this option or features should be provided

Fires:

change (module:ol/events/Event~Event) - Generic change event. Triggered when the revision counter is increased.
change:active (module:ol/Object.ObjectEvent)
propertychange (module:ol/Object.ObjectEvent) - Triggered when a property is changed.

Extends

module:ol/interaction/Pointer~PointerInteraction

Observable Properties

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

Methods

addFeature(feature, opt_listen) interaction/Snap.js, line 206

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

Name	Type	Description
`feature`	module:ol/Feature~Feature	Feature.
`listen`	boolean	Whether to listen to the feature change or not Defaults to `true`.

changed() inherited Observable.js, line 36

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

get(key){*} inherited Object.js, line 119

Gets a value.

Name	Type	Description
`key`	string	Key name.

Returns:

Value.

getActive(){boolean} inherited interaction/Interaction.js, line 60

Return whether the interaction is currently active.

Returns:

true if the interaction is active, false otherwise.

getKeys(){Array.<string>} inherited Object.js, line 132

Get a list of object property names.

Returns:

List of property names.

getMap(){module:ol/PluggableMap~PluggableMap} inherited interaction/Interaction.js, line 69

Get the map associated with this interaction.

Returns:

Map.

getProperties(){Object.<string, *>} inherited Object.js, line 141

Get an object of all property names and values.

Returns:

Object.

getRevision(){number} inherited Observable.js, line 47

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

Returns:

Revision.

handleEvent(mapBrowserEvent){boolean} inherited interaction/Interaction.js, line 79

Handles the map browser event.

Name	Type	Description
`mapBrowserEvent`	module:ol/MapBrowserEvent~MapBrowserEvent	Map browser event.

Returns:

false to stop event propagation.

on(type, listener){module:ol/events~EventsKey|Array.<module:ol/events~EventsKey>} inherited Observable.js, line 60

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){module:ol/events~EventsKey|Array.<module:ol/events~EventsKey>} inherited Observable.js, line 82

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, opt_unlisten) interaction/Snap.js, line 321

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

Name	Type	Description
`feature`	module:ol/Feature~Feature	Feature
`unlisten`	boolean	Whether to unlisten to the feature change or not. Defaults to `true`.

set(key, value, opt_silent) inherited Object.js, line 164

Sets a value.

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

setActive(active) inherited interaction/Interaction.js, line 89

Activate or deactivate the interaction.

Name	Type	Description
`active`	boolean	Active.

setProperties(values, opt_silent) inherited Object.js, line 183

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.

un(type, listener) inherited Observable.js, line 101

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, opt_silent) inherited Object.js, line 195

Unsets a property.

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