From cf6cd968ece9585b4fd185f26e3c39739d3420c1 Mon Sep 17 00:00:00 2001
From: Andreas Hocevar <andreas.hocevar@gmail.com>
Date: Wed, 5 Apr 2017 09:41:56 +0200
Subject: [PATCH] Add example for constrained wheel zooming

---
 examples/mousewheel-zoom.html | 12 ++++++++++++
 examples/mousewheel-zoom.js   | 25 +++++++++++++++++++++++++
 2 files changed, 37 insertions(+)
 create mode 100644 examples/mousewheel-zoom.html
 create mode 100644 examples/mousewheel-zoom.js

diff --git a/examples/mousewheel-zoom.html b/examples/mousewheel-zoom.html
new file mode 100644
index 0000000000..64ac29f801
--- /dev/null
+++ b/examples/mousewheel-zoom.html
@@ -0,0 +1,12 @@
+---
+layout: example.html
+title: Mousewheel/Trackpad Zoom
+shortdesc: Restrict wheel/trackpad zooming to integer zoom levels.
+docs: >
+  By default, the `ol.interaction.MouseWheelZoom` can leave the map at
+  fractional zoom levels. If instead you want to constrain wheel/trackpad
+  zooming to integer zoom levels, set <code>constrainResolution: true</code>
+  when constructing the interaction.
+tags: "trackpad, mousewheel, zoom, interaction"
+---
+<div id="map" class="map"></div>
diff --git a/examples/mousewheel-zoom.js b/examples/mousewheel-zoom.js
new file mode 100644
index 0000000000..17f7c91af6
--- /dev/null
+++ b/examples/mousewheel-zoom.js
@@ -0,0 +1,25 @@
+goog.require('ol.Map');
+goog.require('ol.View');
+goog.require('ol.interaction');
+goog.require('ol.interaction.MouseWheelZoom');
+goog.require('ol.layer.Tile');
+goog.require('ol.source.OSM');
+
+
+var map = new ol.Map({
+  interactions: ol.interaction.defaults({mouseWheelZoom: false}).extend([
+    new ol.interaction.MouseWheelZoom({
+      constrainResolution: true // force zooming to a integer zoom
+    })
+  ]),
+  layers: [
+    new ol.layer.Tile({
+      source: new ol.source.OSM()
+    })
+  ],
+  target: 'map',
+  view: new ol.View({
+    center: [0, 0],
+    zoom: 2
+  })
+});