Rotate marker in Leaflet

Question

How can I rotate a marker in leaflet? I will have a lot of markers, all with a rotation angle.

I\'ve tried this solution from runanet/coomsie at Leaflet on GitH

Answer 1

What works very well for me is adding a data-rotate="[angle]" attribute to each marker. This allows you to call the following JQuery statement on each refresh when necessary:

    $('.your-marker-class').each(function () {            
        var deg = $(this).data('rotate') || 0;
        var rotate = 'rotate(' + $(this).data('rotate') + 'deg) scale(0.5,0.5)';
        $(this).css({
            '-webkit-transform': rotate,
            '-moz-transform': rotate,
            '-o-transform': rotate,
            '-ms-transform': rotate,
            'transform': rotate
        });
    });

Works very fast and with hundreds/thousands of markers. Found this method in some other post somewhere on the internets but seemed right to share here also.

Answer 2

Running the code as it is, the icon will disappear when you try to rotate it in Firefox (try rotating on a mouseclick instead of on load and you will see that the icon appears before you try to rotate it), but I'm willing to bet it will work (the first time) in a webkit browser. The reason is the transform lines:

this._icon.style.WebkitTransform = this._icon.style.WebkitTransform + ' rotate(' + this.options.iconAngle + 'deg)';
this._icon.style.MozTransform = 'rotate(' + this.options.iconAngle + 'deg)';

Firefox also uses CSS transforms to position icons, so before rotation it will have Moztransform will have a value of for example "translate(956px, 111px)". The way the code is now, it will replace that with simply "rotate(90deg)" and Firefox won't know where to place the icon.

You want Moztransform to have a value of "translate(956px, 111px) rotate(90deg)", so if you use this code it will work the first time, like in webkit.

this._icon.style.MozTransform = this._icon.style.MozTransform  + ' rotate(' + this.options.iconAngle + 'deg)';

However, it will break on the next rotate, so you really need to set both the translation and rotation in one go, like this:

this._icon.style.MozTransform = L.DomUtil.getTranslateString(pos) + ' rotate(' + this.options.iconAngle + 'deg)';

Then you can get rid of the L.DomUtil.setPosition(this._icon, pos); at the start.

Answer 3

This solution is by far the easiest: https://github.com/bbecquet/Leaflet.RotatedMarker

Note: it only modifies the existing marker, allowing two more options (rotationAngle and rotationOrigin).

The solution works very well. As per the GitHub page, a usage example:

L.marker([48.8631169, 2.3708919], {
    rotationAngle: 45
}).addTo(map);

Answer 4

If you're using react-leaflet, I built upon this idea (https://github.com/bbecquet/Leaflet.RotatedMarker) to create a React component that extends Marker and accepts both rotation and rotationOrigin as a prop.

// Libs
import L from 'leaflet'

// Components
import { ExtendableMarker } from 'react-leaflet-extendable'

// HOCS
import { withLeaflet } from 'react-leaflet'

const proto_setPos = L.Marker.prototype._setPos

const LeafletMarker = L.Marker.extend({
  _setPos(pos: [number, number]) {
    proto_setPos.call(this, pos)
    this._setRotation(this.options.rotation)
  },
  _setRotation(rotation: number | null | undefined) {
    if (typeof rotation === 'number') {
      this._icon.style[L.DomUtil.TRANSFORM + 'Origin'] = this.options.rotationOrigin || 'center'
      const transform = this._icon.style[L.DomUtil.TRANSFORM] + ` rotate(${rotation}deg)`
      this._icon.style[L.DomUtil.TRANSFORM] = transform
    }
  },
})

const createRotatedMarker = (pos: [number, number], options: any) => {
  return new LeafletMarker(pos, options)
}

class RotatedMarker extends ExtendableMarker {
  public createLeafletElement() {
    return createRotatedMarker(this.props.position, { ...this.props })
  }
}

export default withLeaflet(RotatedMarker)