Replicate event pinch from a div to openlayer map - events

Question

Good afternoon,
I have a div over the ol3 map with one list of marker. When the user clic on a marker, the center's map is updated with the coordinate of this marker.
I tried that the user have the possibility to zoom on the map when he "pinch" on the layer on top.
I successed to intercept the event on the "layerOnTop" and replicate it to the map layer. With console.log, I saw that the job is correctly done but there is any reaction on the map.
You can see the code : http://jsfiddle.net/2ek4j3a4/
var center = ol.proj.transform([4.90756, 45.5172], 'EPSG:4326', 'EPSG:3857');
var map = new ol.Map({
layers: [new ol.layer.Tile({source: new ol.source.OSM()})],
target: 'map',
controls: ol.control.defaults({attributionOptions: ({ collapsible: false})}),
view: new ol.View({center: center,zoom: 12})
});
$('#layerOnTop').on("touchmove", function(event) {
var scale = event.originalEvent.touches;
if (scale.length==2) {
event.preventDefault();
var bottomEvent = new $.Event("touchmove");
bottomEvent.pageX = event.pageX;
bottomEvent.pageY = event.pageY;
$("#map").trigger(bottomEvent);
}
});
$('#map').on("touchmove", function(event) {console.log('ok')})
I did my test with an Android phone.
Somebody have an idea, please ?

Answer 1

I finally found :) There was 2 errors in my code :
1) target should be the canvas element in div#map and not #map himself
2) I fixed the touch identifier by Date.now() and add +1 for the second, it was certainely too big
See below the code if one day somebody search ...
$('#layerOnTop').on("touchstart touchmove touchend", function(event) {
view = document.getElementById('map').ownerDocument.defaultView;
if (event.originalEvent.touches.length==2) {
var target = document.getElementById('map').getElementsByTagName('canvas')[0];
var pageX1 = event.originalEvent.touches[0].pageX;
var pageY1 = event.originalEvent.touches[0].pageY;
var pageX2 = event.originalEvent.touches[1].pageX;
var pageY2 = event.originalEvent.touches[1].pageY;
var touch1 = document.createTouch(view, target, 0, pageX1, pageY1, 0, 0);
var touch2 = document.createTouch(view, target, 1, pageX2, pageY2, 0, 0);
var touchList = document.createTouchList(touch1, touch2);
var touchEvent = new TouchEvent(event.type, {cancelable: true, bubbles: true, touches: touchList, targetTouches: touchList, changedTouches: touchList})
target.dispatchEvent(touchEvent);
}
});
http://jsfiddle.net/2ek4j3a4/7/