Leaflet.Snap

Enables snapping of draggable markers to polylines and other layers !

Check out the demo !

It depends on Leaflet.GeometryUtil.

For snapping on shape drawing or edition snapping, it also depends on Leaflet.draw.

If your guide layer contains several thousands for features, adding the LayerIndex is recommended, this plugin takes advantage of the spatial index if it is available.

Usage

• Add leaflet.snap.js and leaflet.geometryutil.js (optionally leaflet.draw.js)

For markers :

 
    var guideLayer = ...;
 
    var marker = L.marker([48.488, 1.395]).addTo(map);
        marker.snapediting = new L.Handler.MarkerSnap(map, marker);
        marker.snapediting.addGuideLayer(guideLayer);
        marker.snapediting.enable();

For Leaflet.Draw :

 
    var guideLayers = [guides, road];
 
    map.drawControl.setDrawingOptions({
        polyline: { guideLayers: guideLayers },
        polygon: { guideLayers: guideLayers, snapDistance: 5 },
    });

For editing existing polyline :

    var polyline = L.polyline(...).addTo(map);
        polyline.snapediting = new L.Handler.PolylineSnap(map, polyline);
        polyline.snapediting.addGuideLayer(guideLayer);
        polyline.snapediting.enable();

Both L.Handler.MarkerSnap and L.Handler.PolylineSnap accept options as a third argument.

For editing existing polyline with L.EditToolbar.SnapEdit :

L.EditToolbar.SnapEdit is an extension of L.EditToolbar.Edit in Leaflet.draw.

var polyline = L.polyline(...).addTo(map);
var editToolbar = new L.EditToolbar.SnapEdit(map, {
   featureGroup: L.featureGroup([polyline]),
   snapOptions: {
      guideLayers: [guideLayer]
   }
});
 
editToolbar.enable();

L.EditToolbar.SnapEdit accepts options and initial guide layers.

Options:

snapDistance : (default 15) distance in pixels where snapping occurs

snapVertices : (default true) whether layers vertices add additional snap attraction

Events :

snap ( layer, latlng ) : fired when snapped to layer at latlng

unsnap ( layer ) : fired when unsnapped from layer

CHANGELOG

0.0.4

• Fix to use leaflet-draw ^0.3.0
• Delete git module and use node module instead
• Can Snap for 'editing existing polyline with L.EditToolbar.SnapEdit'
• Example can be use with http / https

0.0.3

• Set the newly drawn point/vertex to the snapped location

0.0.2

• Disable snapping when the feature is deleted

0.0.1

• Fix Snaping if guide layer has Leaflet.LayerIndex

TODO

• Add init hooks to simplify initialization

Authors

• Mathieu Leplatre
• Tobias Bieniek
• Frédéric Bonifas