From e390ff80eaa5932fbd71c75ea08aeeb3e9c4a9bf Mon Sep 17 00:00:00 2001
From: ahocevar <andreas.hocevar@gmail.com>
Date: Wed, 26 Sep 2012 18:27:45 +0200
Subject: [PATCH] Adding zoom control

---
 demos/full-screen/full-screen.js |   2 +
 src/ol/control/zoom.js           | 125 +++++++++++++++++++++++++++++++
 2 files changed, 127 insertions(+)
 create mode 100644 src/ol/control/zoom.js

diff --git a/demos/full-screen/full-screen.js b/demos/full-screen/full-screen.js
index a6b6bfac09..e333655538 100644
--- a/demos/full-screen/full-screen.js
+++ b/demos/full-screen/full-screen.js
@@ -5,6 +5,7 @@ goog.require('ol.Collection');
 goog.require('ol.Coordinate');
 goog.require('ol.Map');
 goog.require('ol.RendererHint');
+goog.require('ol.control.Zoom');
 goog.require('ol.layer.MapQuestOpenAerial');
 
 
@@ -20,3 +21,4 @@ var map = new ol.Map(document.getElementById('map'), {
   layers: new ol.Collection([layer]),
   zoom: 0
 });
+var zoom = new ol.control.Zoom(map, layer.getStore().getResolutions());
diff --git a/src/ol/control/zoom.js b/src/ol/control/zoom.js
new file mode 100644
index 0000000000..e9c12956b0
--- /dev/null
+++ b/src/ol/control/zoom.js
@@ -0,0 +1,125 @@
+goog.provide('ol.control.Zoom');
+
+goog.require('goog.dom');
+goog.require('goog.dom.TagName');
+goog.require('goog.events');
+goog.require('goog.events.EventType');
+goog.require('ol.Projection');
+goog.require('ol.control.Control');
+
+
+
+/**
+ * @constructor
+ * @extends {ol.control.Control}
+ * @param {ol.Map} map Map.
+ * @param {Array.<number>=} opt_resolutions The resolutions to zoom to.
+ */
+ol.control.Zoom = function(map, opt_resolutions) {
+
+  goog.base(this, map);
+
+  if (!goog.isDef(opt_resolutions)) {
+    opt_resolutions = new Array(19);
+    for (var z = 0; z <= 18; ++z) {
+      opt_resolutions[z] = ol.Projection.EPSG_3857_HALF_SIZE / (128 << z);
+    }
+  }
+
+  /**
+   * @type {Function}
+   * @private
+   */
+  this.constraint_ =
+      ol.interaction.ResolutionConstraint.createSnapToResolutions(
+          opt_resolutions);
+
+  /**
+   * @type {Element}
+   * @private
+   */
+  this.divElement_ = goog.dom.createDom(goog.dom.TagName.DIV, 'ol-zoom');
+
+  /**
+   * @type {Element}
+   * @private
+   */
+  this.inButton_ = goog.dom.createDom(goog.dom.TagName.DIV, 'ol-zoom-in',
+      goog.dom.createDom(goog.dom.TagName.A, {'href': '#zoomIn'}));
+
+  /**
+   * @type {Element}
+   * @private
+   */
+  this.outButton_ = goog.dom.createDom(goog.dom.TagName.DIV, 'ol-zoom-out',
+      goog.dom.createDom(goog.dom.TagName.A, {'href': '#zoomOut'}));
+
+  goog.dom.setTextContent(
+      /** @type {Element} */ (this.inButton_.firstChild), '+');
+  goog.dom.setTextContent(
+      /** @type {Element} */ (this.outButton_.firstChild), '\u2212');
+  goog.dom.append(this.divElement_, this.inButton_, this.outButton_);
+  goog.dom.append(/** @type {!Node} */ (map.getViewport()), this.divElement_);
+
+  goog.events.listen(this.inButton_, goog.events.EventType.CLICK,
+      this.handleIn_, false, this);
+  goog.events.listen(this.outButton_, goog.events.EventType.CLICK,
+      this.handleOut_, false, this);
+
+};
+goog.inherits(ol.control.Zoom, ol.control.Control);
+
+
+/**
+ * @inheritDoc
+ */
+ol.control.Zoom.prototype.getElement = function() {
+  return this.divElement_;
+};
+
+
+/**
+ * @param {goog.events.BrowserEvent} browserEvent The browser event to handle.
+ * @private
+ */
+ol.control.Zoom.prototype.handleIn_ = function(browserEvent) {
+  browserEvent.stopPropagation();
+  browserEvent.preventDefault();
+  this.zoom_(1);
+};
+
+
+/**
+ * @param {goog.events.BrowserEvent} browserEvent The browser event to handle.
+ * @private
+ */
+ol.control.Zoom.prototype.handleOut_ = function(browserEvent) {
+  browserEvent.stopPropagation();
+  browserEvent.preventDefault();
+  this.zoom_(-1);
+};
+
+
+/**
+ * @param {number} delta Delta.
+ * @private
+ */
+ol.control.Zoom.prototype.zoom_ = function(delta) {
+  var map = this.getMap();
+  var resolution = this.constraint_(map.getResolution(), delta);
+  map.setResolution(resolution);
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.control.Zoom.prototype.disposeInternal = function() {
+  goog.dom.removeNode(this.inButton_);
+  goog.dom.removeNode(this.outButton_);
+  goog.dom.removeNode(this.divElement_);
+  delete this.inButton_;
+  delete this.outButton_;
+  delete this.divElement_;
+  goog.base(this, 'disposeInternal');
+};