OpenLayers v4.0.1 API - Class: ImageVector

# Class: ImageVector

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

## ol.source.ImageVector

An image source whose images are canvas elements into which vector features read from a vector source (`ol.source.Vector`) are drawn. An `ol.source.ImageVector` object is to be used as the `source` of an image layer (`ol.layer.Image`). Image layers are rotated, scaled, and translated, as opposed to being re-rendered, during animations and interactions. So, like any other image layer, an image layer configured with an `ol.source.ImageVector` will exhibit this behaviour. This is in contrast to a vector layer, where vector features are re-drawn during animations and interactions.

#### new ol.source.ImageVector(options)

src/ol/source/imagevector.js, line 32

  Name | Type | Description
  --- | --- | ---

  `options`

  Options.

  Name | Type | Description
  --- | --- | ---
  `attributions` | ol.AttributionLike | undefined | Attributions.
  `logo` | string | olx.LogoOptions | undefined | Logo.
  `projection` | ol.ProjectionLike | Projection.
  `ratio` | number | undefined | Ratio. 1 means canvases are the size of the map viewport, 2 means twice the width and height of the map viewport, and so on. Must be `1` or higher. Default is `1.5`.
  `renderBuffer` | number | undefined | The buffer around the viewport extent used by the renderer when getting features from the vector source for the rendering or hit-detection. Recommended value: the size of the largest symbol, line width or label. Default is 100 pixels.
  `resolutions` | Array.<number> | undefined | Resolutions. If specified, new canvases will be created for these resolutions only.
  `source` | ol.source.Vector | The vector source from which the vector features drawn in canvas elements are read. Required.
  `style` | ol.style.Style | Array.<ol.style.Style> | ol.StyleFunction | undefined | Style to use when rendering features to the canvas.

  ##### 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.source.ImageCanvas

### Methods

#### changed() inherited

src/ol/observable.js, line 58

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

#### 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.

#### getAttributions(){Array.<ol.Attribution>} inherited

src/ol/source/source.js, line 113

  Get the attributions of the source.

  ##### Returns:

  Attributions.

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

src/ol/object.js, line 115

  Get a list of object property names.

  ##### Returns:

  List of property names.

#### getLogo(){string|olx.LogoOptions|undefined} inherited

src/ol/source/source.js, line 123

  Get the logo of the source.

  ##### Returns:

  Logo.

#### getProjection(){ol.proj.Projection} inherited

src/ol/source/source.js, line 133

  Get the projection of the source.

  ##### Returns:

  Projection.

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

src/ol/object.js, line 125

  Get an object of all property names and values.

  ##### Returns:

  Object.

#### 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.

#### getSource(){ol.source.Vector}

src/ol/source/imagevector.js, line 186

  Get a reference to the wrapped source.

  ##### Returns:

  Source.

#### getState(){ol.source.State} inherited

src/ol/source/source.js, line 150

  Get the state of the source, see `ol.source.State` for possible states.

  ##### Returns:

  State.

#### getStyle(){ol.style.Style|Array.<ol.style.Style>|ol.StyleFunction}

src/ol/source/imagevector.js, line 198

  Get the style for features. This returns whatever was passed to the `style` option at construction or to the `setStyle` method.

  ##### Returns:

  Layer style.

#### getStyleFunction(){ol.StyleFunction|undefined}

src/ol/source/imagevector.js, line 208

  Get the style function.

  ##### Returns:

  Layer style function.

#### 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.

#### refresh() inherited

src/ol/source/source.js, line 167

  Refreshes the source and finally dispatches a 'change' event.

#### 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.

#### setAttributions(attributions) inherited

src/ol/source/source.js, line 179

  Set the attributions of the source.

  Name | Type | Description
  --- | --- | ---
  `attributions` | ol.AttributionLike | undefined | Attributions. Can be passed as `string`, `Array<string>`, ``ol.Attribution``, `Array<`ol.Attribution`>` or `undefined`.

#### 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.

#### setStyle(style)

src/ol/source/imagevector.js, line 297

  Set the style for features. This can be a single style object, an array of styles, or a function that takes a feature and resolution and returns an array of styles. If it is `undefined` the default style is used. If it is `null` the layer has no style (a `null` style), so only features that have their own styles will be rendered in the layer. See `ol.style` for information on the default style.

  Name | Type | Description
  --- | --- | ---
  `style` | ol.style.Style | Array.<ol.style.Style> | ol.StyleFunction | undefined | Layer style.

#### 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.