Split TouchRotateAndZoom interaction.

Split TouchRotateAndZoom interaction into two new interaction: TouchRotate and TouchZoom.
2013-02-25 10:30:04 +01:00
parent 940ba8afa7
commit c0aa50abfc
5 changed files with 126 additions and 39 deletions
--- a/src/ol/interaction/touchzoominteraction.js
+++ b/src/ol/interaction/touchzoominteraction.js
@@ -0,0 +1,98 @@
+// FIXME works for View2D only
+
+goog.provide('ol.interaction.TouchZoom');
+
+goog.require('goog.asserts');
+goog.require('ol.View');
+goog.require('ol.ViewHint');
+goog.require('ol.interaction.Touch');
+
+
+
+/**
+ * @constructor
+ * @extends {ol.interaction.Touch}
+ */
+ol.interaction.TouchZoom = function() {
+
+  goog.base(this);
+
+  /**
+   * @private
+   * @type {number|undefined}
+   */
+  this.lastDistance_;
+
+};
+goog.inherits(ol.interaction.TouchZoom, ol.interaction.Touch);
+
+
+/**
+ * @inheritDoc
+ */
+ol.interaction.TouchZoom.prototype.handleTouchMove =
+    function(mapBrowserEvent) {
+  goog.asserts.assert(this.targetTouches.length >= 2);
+  var scaleDelta = 1.0;
+
+  var touch0 = this.targetTouches[0];
+  var touch1 = this.targetTouches[1];
+  var dx = touch0.clientX - touch1.clientX;
+  var dy = touch0.clientY - touch1.clientY;
+
+  // distance between touches
+  var distance = Math.sqrt(dx * dx + dy * dy);
+
+  if (goog.isDef(this.lastDistance_)) {
+    scaleDelta = this.lastDistance_ / distance;
+  }
+  this.lastDistance_ = distance;
+
+  var map = mapBrowserEvent.map;
+  var view = map.getView();
+
+  // scale anchor point.
+  var viewportPosition = goog.style.getClientPosition(map.getViewport());
+  var centroid = ol.interaction.Touch.centroid(this.targetTouches);
+  centroid.x -= viewportPosition.x;
+  centroid.y -= viewportPosition.y;
+  var anchor = map.getCoordinateFromPixel(centroid);
+
+  // scale, bypass the resolution constraint
+  view.zoom_(map, view.getResolution() * scaleDelta, anchor);
+
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.interaction.TouchZoom.prototype.handleTouchEnd =
+    function(mapBrowserEvent) {
+  if (this.targetTouches.length < 2) {
+    var map = mapBrowserEvent.map;
+    var view = map.getView();
+    // take the resolution constraint into account
+    view.zoomToResolution(map, view.getResolution());
+    view.setHint(ol.ViewHint.PANNING, -1);
+    return false;
+  } else {
+    return true;
+  }
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.interaction.TouchZoom.prototype.handleTouchStart =
+    function(mapBrowserEvent) {
+  if (this.targetTouches.length >= 2) {
+    var view = mapBrowserEvent.map.getView();
+    this.lastDistance_ = undefined;
+    view.setHint(ol.ViewHint.PANNING, 1);
+    return true;
+  } else {
+    return false;
+  }
+};