Rotate feature interaction for OpenLayers

Plugin adds interaction that allows to rotate vector features around some anchor.

Demo

NOTE: ol-rotate-feature starting from version v2.x supports ol v5.x. To use it with previous version of the OpenLayers ol package you should install v1.x version.

Installation

Install it thought NPM (recommended):

# ES6 version for bundling with Webpack, Rollup or etc.
npm install ol ol-rotate-feature

# to use UMD version 'openlayers' package should be installed (not recommended)
npm install openlayers

Or add from CDN:

<script src="https://unpkg.com/openlayers@latest/dist/ol.js"></script>
<script src="https://unpkg.com/ol-rotate-feature@latest/dist/bundle.min.js"></script>

Note

Plugin is available in 2 versions: as UMD module and as ES2015 module:

• RECOMMENDED: ES2015 version (dist/bundle.es.js) should be used with ol package (you should install it manually).
• UMD version (dist/bundle[.min].js) should be used with openlayers package. You can install ol package as dev dependency to suppress NPM warning about required peer dependencies.

Usage

Plugin may be used as ES2015 module and ol v5.x (recommended):

import Map from 'ol/Map'
...
import RotateFeatureInteraction from 'ol-rotate-feature'

Use UMD bundle with deprecated openlayers v4.x package (not recommended but supported)

const ol = require('openlayers')
...
const RotateFeatureInteraction = require('ol-rotate-feature')

In Browser environment you should add script tag pointing to UMD module after OpenLayers js files.

<script src="https://unpkg.com/openlayers@latest/dist/ol.js"></script>
<script src="https://unpkg.com/ol-rotate-feature@latest/dist/bundle.min.js"></script>
<script>
  // plugin exports global variable RotateFeatureInteraction
  // in addition it also exported to `ol.interaction.RotateFeature` field (for backward compatibility).
</script>

Options

Option	Type	Description
features	ol.Collection<ol.Feature>	The features the interaction works on. Required.
style	ol.style.Style | Array<ol.style.Style> | ol.style.StyleFunction | undefined	Style of the overlay with interaction helper features.
angle	number | undefined	Initial angle in radians (positive is counter-clockwise), applied for features already added to collection. Default is 0.
anchor	number[] | ol.Coordinate | undefined	Initial anchor coordinate. Default is center of features extent.
condition	module:ol/events/condition~Condition	A function that takes an module:ol/MapBrowserEventMapBrowserEvent and returns a boolean to indicate whether that event should be handled. Default is module:ol/events/conditionplatformModifierKeyOnly

Methods

// Set current angle of interaction features.
RotateFeatureInteraction.prototype.setAngle(angle : number)

// Returns current angle of interaction features.
RotateFeatureInteraction.prototype.getAngle() : number

// Set current anchor position.
RotateFeatureInteraction.prototype.setAnchor(anchor? : number[] | ol.Coordinate)

// Returns current anchor position.
RotateFeatureInteraction.prototype.getAnchor() : number[] | ol.Coordinate | undefined 

Events

All events triggered by the interaction are instances of RotateFeatureEvent.

Members

• features ol.Collection The features being rotated.
• angle number Current angle in radians.
• anchor ol.Coordinate Current anchor position.

Event	Arguments	Description
rotatestart	RotateFeatureEvent	Triggered upon feature rotate start.
rotating	RotateFeatureEvent	Triggered upon feature rotating.
rotateend	RotateFeatureEvent	Triggered upon feature rotation end.

Example usage:

import Map from 'ol/Map'
import View from 'ol/View'
import TileLayer from 'ol/layer/Tile'
import VectorLayer from 'ol/layer/Vector'
import OSMSource from 'ol/source/OSM'
import VectorSource from 'ol/source/Vector'
import Feature from 'ol/Feature'
import Point from 'ol/geom/Point'
import LineString from 'ol/geom/LineString'
import Polygon from 'ol/geom/Polygon'
import Select from 'ol/interaction/Select'
import RotateFeatureInteraction from 'ol-rotate-feature'

const point = new Feature({
  name: 'point',
  geometry: new Point([ 2384267.0573564973, 7557371.884852641 ])
})
const line = new Feature({
  name: 'line',
  geometry: new LineString([ [ -603697.2100018249, -239432.60826165066 ], [ 4190433.20404443, 2930563.8287811787 ] ])
})
const polygon = new Feature({
  name: 'polygon',
  geometry: new Polygon([ [
    [ -14482348.171434438, 6661491.741627443 ],
    [ -9541458.663080638, 6221214.458704827 ],
    [ -11473786.738129886, 3300708.4819848104 ],
    [ -14482348.171434438, 6661491.741627443 ]
  ] ])
})

const map = new Map({
  view: new View({
    center: [ 0, 0 ],
    zoom: 2
  }),
  layers: [
    new TileLayer({
      source: new OSMSource()
    }),
    new VectorLayer({
      source: new VectorSource({
        projection: 'EPSG:33857',
        features: [ point, line, polygon ]
      })
    })
  ],
  target: 'map',
  projection: 'EPSG:3857'
})

const select = new Select()
select.getFeatures().extend([ point, line, polygon ])

const rotate = new RotateFeatureInteraction({
  features: select.getFeatures(),
  anchor: [ 0, 0 ],
  angle: -90 * Math.PI / 180
})

rotate.on('rotatestart', evt => console.log('rotate start', evt))
rotate.on('rotating', evt => console.log('rotating', evt))
rotate.on('rotateend', evt => console.log('rotate end', evt))

map.addInteraction(select)
map.addInteraction(rotate)

Example of usage in Browser environment in test/umd.html.

Getting total angle or last anchor coordinates after rotation:

rotate.on('rotateend', evt => {
    // get total angle in degrees
    console.log(evt.angle + ' is '+ (-1 * evt.angle * 180 / Math.PI ) + '°')
    // get last anchor coordinates
    console.log(evt.anchor)
})

License

MIT (c) 2016-2018, Vladimir Vershinin