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diff --git a/chimere/static/ol3-layerswitcher/ol3-layerswitcher.js b/chimere/static/ol3-layerswitcher/ol3-layerswitcher.js
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+/**
+ * OpenLayers 3 Layer Switcher Control.
+ * See [the examples](./examples) for usage.
+ * @constructor
+ * @extends {ol.control.Control}
+ * @param {Object} opt_options Control options, extends olx.control.ControlOptions adding:
+ *                              **`tipLabel`** `String` - the button tooltip.
+ */
+ol.control.LayerSwitcher = function(opt_options) {
+
+    var options = opt_options || {};
+
+    var tipLabel = options.tipLabel ?
+      options.tipLabel : 'Legend';
+
+    this.mapListeners = [];
+
+    this.hiddenClassName = 'ol-unselectable ol-control layer-switcher';
+    if (ol.control.LayerSwitcher.isTouchDevice_()) {
+        this.hiddenClassName += ' touch';
+    }
+    this.shownClassName = this.hiddenClassName + ' shown';
+
+    var element = document.createElement('div');
+    element.className = this.hiddenClassName;
+
+    var button = document.createElement('button');
+    button.setAttribute('title', tipLabel);
+    element.appendChild(button);
+
+    this.panel = document.createElement('div');
+    this.panel.className = 'panel';
+    element.appendChild(this.panel);
+    ol.control.LayerSwitcher.enableTouchScroll_(this.panel);
+
+    var this_ = this;
+
+    button.onmouseover = function(e) {
+        this_.showPanel();
+    };
+
+    button.onclick = function(e) {
+        e = e || window.event;
+        this_.showPanel();
+        e.preventDefault();
+    };
+
+    this_.panel.onmouseout = function(e) {
+        e = e || window.event;
+        if (!this_.panel.contains(e.toElement || e.relatedTarget)) {
+            this_.hidePanel();
+        }
+    };
+
+    ol.control.Control.call(this, {
+        element: element,
+        target: options.target
+    });
+
+};
+
+ol.inherits(ol.control.LayerSwitcher, ol.control.Control);
+
+/**
+ * Show the layer panel.
+ */
+ol.control.LayerSwitcher.prototype.showPanel = function() {
+    if (this.element.className != this.shownClassName) {
+        this.element.className = this.shownClassName;
+        this.renderPanel();
+    }
+};
+
+/**
+ * Hide the layer panel.
+ */
+ol.control.LayerSwitcher.prototype.hidePanel = function() {
+    if (this.element.className != this.hiddenClassName) {
+        this.element.className = this.hiddenClassName;
+    }
+};
+
+/**
+ * Re-draw the layer panel to represent the current state of the layers.
+ */
+ol.control.LayerSwitcher.prototype.renderPanel = function() {
+
+    this.ensureTopVisibleBaseLayerShown_();
+
+    while(this.panel.firstChild) {
+        this.panel.removeChild(this.panel.firstChild);
+    }
+
+    var ul = document.createElement('ul');
+    this.panel.appendChild(ul);
+    this.renderLayers_(this.getMap(), ul);
+
+};
+
+/**
+ * Set the map instance the control is associated with.
+ * @param {ol.Map} map The map instance.
+ */
+ol.control.LayerSwitcher.prototype.setMap = function(map) {
+    // Clean up listeners associated with the previous map
+    for (var i = 0, key; i < this.mapListeners.length; i++) {
+        this.getMap().unByKey(this.mapListeners[i]);
+    }
+    this.mapListeners.length = 0;
+    // Wire up listeners etc. and store reference to new map
+    ol.control.Control.prototype.setMap.call(this, map);
+    if (map) {
+        var this_ = this;
+        this.mapListeners.push(map.on('pointerdown', function() {
+            this_.hidePanel();
+        }));
+        this.renderPanel();
+    }
+};
+
+/**
+ * Ensure only the top-most base layer is visible if more than one is visible.
+ * @private
+ */
+ol.control.LayerSwitcher.prototype.ensureTopVisibleBaseLayerShown_ = function() {
+    var lastVisibleBaseLyr;
+    ol.control.LayerSwitcher.forEachRecursive(this.getMap(), function(l, idx, a) {
+        if (l.get('type') === 'base' && l.getVisible()) {
+            lastVisibleBaseLyr = l;
+        }
+    });
+    if (lastVisibleBaseLyr) this.setVisible_(lastVisibleBaseLyr, true);
+};
+
+/**
+ * Toggle the visible state of a layer.
+ * Takes care of hiding other layers in the same exclusive group if the layer
+ * is toggle to visible.
+ * @private
+ * @param {ol.layer.Base} The layer whos visibility will be toggled.
+ */
+ol.control.LayerSwitcher.prototype.setVisible_ = function(lyr, visible) {
+    var map = this.getMap();
+    lyr.setVisible(visible);
+    if (visible && lyr.get('type') === 'base') {
+        // Hide all other base layers regardless of grouping
+        ol.control.LayerSwitcher.forEachRecursive(map, function(l, idx, a) {
+            if (l != lyr && l.get('type') === 'base') {
+                l.setVisible(false);
+            }
+        });
+    }
+};
+
+/**
+ * Render all layers that are children of a group.
+ * @private
+ * @param {ol.layer.Base} lyr Layer to be rendered (should have a title property).
+ * @param {Number} idx Position in parent group list.
+ */
+ol.control.LayerSwitcher.prototype.renderLayer_ = function(lyr, idx) {
+
+    var this_ = this;
+
+    var li = document.createElement('li');
+
+    var lyrTitle = lyr.get('title');
+    var lyrId = ol.control.LayerSwitcher.uuid();
+
+    var label = document.createElement('label');
+
+    if (lyr.getLayers && !lyr.get('combine')) {
+
+        li.className = 'group';
+        label.innerHTML = lyrTitle;
+        li.appendChild(label);
+        var ul = document.createElement('ul');
+        li.appendChild(ul);
+
+        this.renderLayers_(lyr, ul);
+
+    } else {
+
+        li.className = 'layer';
+        var input = document.createElement('input');
+        if (lyr.get('type') === 'base') {
+            input.type = 'radio';
+            input.name = 'base';
+        } else {
+            input.type = 'checkbox';
+        }
+        input.id = lyrId;
+        input.checked = lyr.get('visible');
+        input.onchange = function(e) {
+            this_.setVisible_(lyr, e.target.checked);
+        };
+        li.appendChild(input);
+
+        label.htmlFor = lyrId;
+        label.innerHTML = lyrTitle;
+        li.appendChild(label);
+
+    }
+
+    return li;
+
+};
+
+/**
+ * Render all layers that are children of a group.
+ * @private
+ * @param {ol.layer.Group} lyr Group layer whos children will be rendered.
+ * @param {Element} elm DOM element that children will be appended to.
+ */
+ol.control.LayerSwitcher.prototype.renderLayers_ = function(lyr, elm) {
+    var lyrs = lyr.getLayers().getArray().slice().reverse();
+    for (var i = 0, l; i < lyrs.length; i++) {
+        l = lyrs[i];
+        if (l.get('title')) {
+            elm.appendChild(this.renderLayer_(l, i));
+        }
+    }
+};
+
+/**
+ * **Static** Call the supplied function for each layer in the passed layer group
+ * recursing nested groups.
+ * @param {ol.layer.Group} lyr The layer group to start iterating from.
+ * @param {Function} fn Callback which will be called for each `ol.layer.Base`
+ * found under `lyr`. The signature for `fn` is the same as `ol.Collection#forEach`
+ */
+ol.control.LayerSwitcher.forEachRecursive = function(lyr, fn) {
+    lyr.getLayers().forEach(function(lyr, idx, a) {
+        fn(lyr, idx, a);
+        if (lyr.getLayers) {
+            ol.control.LayerSwitcher.forEachRecursive(lyr, fn);
+        }
+    });
+};
+
+/**
+ * Generate a UUID
+ * @returns {String} UUID
+ *
+ * Adapted from http://stackoverflow.com/a/2117523/526860
+ */
+ol.control.LayerSwitcher.uuid = function() {
+    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
+        var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
+        return v.toString(16);
+    });
+}
+
+/**
+* @private
+* @desc Apply workaround to enable scrolling of overflowing content within an
+* element. Adapted from https://gist.github.com/chrismbarr/4107472
+*/
+ol.control.LayerSwitcher.enableTouchScroll_ = function(elm) {
+   if(ol.control.LayerSwitcher.isTouchDevice_()){
+       var scrollStartPos = 0;
+       elm.addEventListener("touchstart", function(event) {
+           scrollStartPos = this.scrollTop + event.touches[0].pageY;
+       }, false);
+       elm.addEventListener("touchmove", function(event) {
+           this.scrollTop = scrollStartPos - event.touches[0].pageY;
+       }, false);
+   }
+};
+
+/**
+ * @private
+ * @desc Determine if the current browser supports touch events. Adapted from
+ * https://gist.github.com/chrismbarr/4107472
+ */
+ol.control.LayerSwitcher.isTouchDevice_ = function() {
+    try {
+        document.createEvent("TouchEvent");
+        return true;
+    } catch(e) {
+        return false;
+    }
+};