gistfile1.coffee

  hoverMarker: (e) =>
    @map.featuresAt(e.point, { radius: 16, layer: 'markers' }, (err, features) =>
      return unless features[0]
      model = @collection.get(features[0].properties.id)
      model.marker = 'secondary-marker'
      return @addToMap()
    )
    @collection.each (model) ->
      model.marker = 'default-marker'
    @addToMap()

  addToMap: =>
    features = @collection.toGeoJSON()
    @sourceObj.setData(features)