1 files changed, 91 insertions, 0 deletions
diff --git a/debian/missing-sources/leaflet.js/map/handler/Map.ScrollWheelZoom.js b/debian/missing-sources/leaflet.js/map/handler/Map.ScrollWheelZoom.js
new file mode 100644
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+++ b/debian/missing-sources/leaflet.js/map/handler/Map.ScrollWheelZoom.js
@@ -0,0 +1,91 @@
+import {Map} from '../Map';
+import {Handler} from '../../core/Handler';
+import * as DomEvent from '../../dom/DomEvent';
+import * as Util from '../../core/Util';
+
+/*
+ * L.Handler.ScrollWheelZoom is used by L.Map to enable mouse scroll wheel zoom on the map.
+ */
+
+// @namespace Map
+// @section Interaction Options
+Map.mergeOptions({
+	// @section Mousewheel options
+	// @option scrollWheelZoom: Boolean|String = true
+	// Whether the map can be zoomed by using the mouse wheel. If passed `'center'`,
+	// it will zoom to the center of the view regardless of where the mouse was.
+	scrollWheelZoom: true,
+
+	// @option wheelDebounceTime: Number = 40
+	// Limits the rate at which a wheel can fire (in milliseconds). By default
+	// user can't zoom via wheel more often than once per 40 ms.
+	wheelDebounceTime: 40,
+
+	// @option wheelPxPerZoomLevel: Number = 60
+	// How many scroll pixels (as reported by [L.DomEvent.getWheelDelta](#domevent-getwheeldelta))
+	// mean a change of one full zoom level. Smaller values will make wheel-zooming
+	// faster (and vice versa).
+	wheelPxPerZoomLevel: 60
+});
+
+export var ScrollWheelZoom = Handler.extend({
+	addHooks: function () {
+		DomEvent.on(this._map._container, 'mousewheel', this._onWheelScroll, this);
+
+		this._delta = 0;
+	},
+
+	removeHooks: function () {
+		DomEvent.off(this._map._container, 'mousewheel', this._onWheelScroll, this);
+	},
+
+	_onWheelScroll: function (e) {
+		var delta = DomEvent.getWheelDelta(e);
+
+		var debounce = this._map.options.wheelDebounceTime;
+
+		this._delta += delta;
+		this._lastMousePos = this._map.mouseEventToContainerPoint(e);
+
+		if (!this._startTime) {
+			this._startTime = +new Date();
+		}
+
+		var left = Math.max(debounce - (+new Date() - this._startTime), 0);
+
+		clearTimeout(this._timer);
+		this._timer = setTimeout(Util.bind(this._performZoom, this), left);
+
+		DomEvent.stop(e);
+	},
+
+	_performZoom: function () {
+		var map = this._map,
+		    zoom = map.getZoom(),
+		    snap = this._map.options.zoomSnap || 0;
+
+		map._stop(); // stop panning and fly animations if any
+
+		// map the delta with a sigmoid function to -4..4 range leaning on -1..1
+		var d2 = this._delta / (this._map.options.wheelPxPerZoomLevel * 4),
+		    d3 = 4 * Math.log(2 / (1 + Math.exp(-Math.abs(d2)))) / Math.LN2,
+		    d4 = snap ? Math.ceil(d3 / snap) * snap : d3,
+		    delta = map._limitZoom(zoom + (this._delta > 0 ? d4 : -d4)) - zoom;
+
+		this._delta = 0;
+		this._startTime = null;
+
+		if (!delta) { return; }
+
+		if (map.options.scrollWheelZoom === 'center') {
+			map.setZoom(zoom + delta);
+		} else {
+			map.setZoomAround(this._lastMousePos, zoom + delta);
+		}
+	}
+});
+
+// @section Handlers
+// @property scrollWheelZoom: Handler
+// Scroll wheel zoom handler.
+Map.addInitHook('addHandler', 'scrollWheelZoom', ScrollWheelZoom);