Class: VectorTile

ol/source/VectorTile~VectorTile 


import VectorTile from 'ol/source/VectorTile.js';

Class for layer sources providing vector data divided into a tile grid, to be used with VectorTileLayer. Although this source receives tiles with vector features from the server, it is not meant for feature editing. Features are optimized for rendering, their geometries are clipped at or near tile boundaries and simplified for a view resolution. See VectorSource for vector sources that are suitable for feature editing.

new VectorTile(options)

source/VectorTile.js, line 102
Name Type Description
attributions AttributionLike | undefined

Attributions.
attributionsCollapsible boolean (defaults to true)

Attributions are collapsible.
cacheSize number | undefined

Initial tile cache size. Will auto-grow to hold at least twice the number of tiles in the viewport.
extent Extent | undefined

Extent.
format FeatureFormat | undefined

Feature format for tiles. Used and required by the default.
overlaps boolean (defaults to true)

This source may have overlapping geometries. Setting this to false (e.g. for sources with polygons that represent administrative boundaries or TopoJSON sources) allows the renderer to optimise fill and stroke operations.
projection ProjectionLike (defaults to 'EPSG:3857')

Projection of the tile grid.
state State | undefined

Source state.
tileClass Class<VectorTile> | undefined

Class used to instantiate image tiles. Default is VectorTile.
maxZoom number (defaults to 22)

Optional max zoom level. Not used if tileGrid is provided.
minZoom number | undefined

Optional min zoom level. Not used if tileGrid is provided.
tileSize number | Size (defaults to 512)

Optional tile size. Not used if tileGrid is provided.
maxResolution number | undefined

Optional tile grid resolution at level zero. Not used if tileGrid is provided.
tileGrid TileGrid | undefined

Tile grid.
tileLoadFunction LoadFunction | undefined

Optional function to load a tile given a URL. Could look like this for pbf tiles:

function(tile, url) {
  tile.setLoader(function(extent, resolution, projection) {
    fetch(url).then(function(response) {
      response.arrayBuffer().then(function(data) {
        const format = tile.getFormat() // ol/format/MVT configured as source format
        const features = format.readFeatures(data, {
          extent: extent,
          featureProjection: projection
        });
        tile.setFeatures(features);
      });
    });
  });
}

If you do not need extent, resolution and projection to get the features for a tile (e.g. for GeoJSON tiles), your tileLoadFunction does not need a setLoader() call. Only make sure to call setFeatures() on the tile:

const format = new GeoJSON({featureProjection: map.getView().getProjection()});
async function tileLoadFunction(tile, url) {
  const response = await fetch(url);
  const data = await response.json();
  tile.setFeatures(format.readFeatures(data));
}
tileUrlFunction UrlFunction | undefined

Optional function to get tile URL given a tile coordinate and the projection.
url string | undefined

URL template. Must include {x}, {y} or {-y}, and {z} placeholders. A {?-?} template pattern, for example subdomain{a-f}.domain.com, may be used instead of defining each one separately in the urls option.
transition number | undefined

A duration for tile opacity transitions in milliseconds. A duration of 0 disables the opacity transition.
urls Array.<string> | undefined

An array of URL templates.
wrapX boolean (defaults to true)

Whether to wrap the world horizontally. When set to false, only one world will be rendered. When set to true, tiles will be wrapped horizontally to render multiple worlds.
zDirection number | NearestDirectionFunction (defaults to 1)

Choose whether to use tiles with a higher or lower zoom level when between integer zoom levels. See getZForResolution.
Fires:

Extends

Methods

changed() inherited

Observable.js, line 68

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

clear()

source/VectorTile.js, line 228

clear TileCache and delete all source tiles

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 135

Gets a value.

Name Type Description
key string

Key name.
Returns:
Value.

getAttributions(){Attribution} inherited

source/Source.js, line 132

Get the attribution function for the source.

Returns:
Attribution function.

getAttributionsCollapsible(){boolean} inherited

source/Source.js, line 140
Returns:
Attributions are collapsible.

getFeaturesInExtent(extent){Array<FeatureLike>}

source/VectorTile.js, line 184

Get features whose bounding box intersects the provided extent. Only features for cached tiles for the last rendered zoom level are available in the source. So this method is only suitable for requesting tiles for extents that are currently rendered.

Features are returned in random tile order and as they are included in the tiles. This means they can be clipped, duplicated across tiles, and simplified to the render resolution.

Name Type Description
extent Extent

Extent.
Returns:
Features.

getKeys(){Array.<string>} inherited

Object.js, line 148

Get a list of object property names.

Returns:
List of property names.

getProjection(){Projection | null} inherited

source/Source.js, line 149

Get the projection of the source.

Returns:
Projection.

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

Object.js, line 157

Get an object of all property names and values.

Returns:
Object.

getRevision(){number} inherited

Observable.js, line 79

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

Returns:
Revision.

getState(){State} inherited

source/Source.js, line 173

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

Returns:
State.

getTileGrid(){TileGrid | null} inherited

source/Tile.js, line 266

Return the tile grid of the tile source.

Returns:
Tile grid.

getTileLoadFunction(){LoadFunction} inherited

source/UrlTile.js, line 101

Return the tile load function of the source.

Returns:
TileLoadFunction

getTileUrlFunction(){UrlFunction} inherited

source/UrlTile.js, line 110

Return the tile URL function of the source.

Returns:
TileUrlFunction

getUrls(){!Array.<string> | null} inherited

source/UrlTile.js, line 123

Return the URLs used for this source. When a tileUrlFunction is used instead of url or urls, null will be returned.

Returns:
URLs.

on(type, listener){EventsKey | Array<EventsKey>} inherited

Observable.js, line 152

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 164

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.

refresh() inherited

source/Source.js, line 195

Refreshes the source. The source will be cleared, and data from the server will be reloaded.

set(key, value, silent) inherited

Object.js, line 207

Sets a value.

Name Type Description
key string

Key name.
value *

Value.
silent boolean | undefined

Update without triggering an event.

setAttributions(attributions) inherited

source/Source.js, line 206

Set the attributions of the source.

Name Type Description
attributions AttributionLike | undefined

Attributions. Can be passed as string, Array<string>, Attribution, or undefined.

setProperties(values, silent) inherited

Object.js, line 227

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 | undefined

Update without triggering an event.

setTileLoadFunction(tileLoadFunction) inherited

source/UrlTile.js, line 159

Set the tile load function of the source.

Name Type Description
tileLoadFunction LoadFunction

Tile load function.

setTileUrlFunction(tileUrlFunction, key) inherited

source/UrlTile.js, line 171

Set the tile URL function of the source.

Name Type Description
tileUrlFunction UrlFunction

Tile URL function.
key string | undefined

Optional new tile key for the source.

setUrl(url) inherited

source/UrlTile.js, line 186

Set the URL to use for requests.

Name Type Description
url string

URL.

setUrls(urls) inherited

source/UrlTile.js, line 197

Set the URLs to use for requests.

Name Type Description
urls Array.<string>

URLs.

un(type, listener) inherited

Observable.js, line 173

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 251

Unsets a property.

Name Type Description
key string

Key name.
silent boolean | undefined

Unset without triggering an event.