I am using GPX data to display routes with OpenLayers 3 and my attempts of zooming to fit the GPS trace have been thus far unsuccessful. I only ever got it working in debug mode on Firefox, where it always zooms correctly, however when just loading the web page nothing happens. Also when drag-dropping a GPX file on the maps the zoom works again, but the same code without projection transformation does not work when displaying the original GPX without the dragAndDropInteraction interaction.
Here is the code snippet that is supposed to make the map zoom to fit the trace:
//fit view
var extent = vector.getSource().getExtent();
var mapProjection = map.getView().getProjection();
ConvertedExtent = ol.proj.transformExtent(extent, 'EPSG:3857', 'EPSG:4326');
mapSize = map.getSize();
map.getView().fitExtent(extent, mapSize);
After calling .getSource().getExtent() the extent array contains the following:
[1215055.5815933049, 6137851.406357965, 1286274.229579136, 6175156.521239913]
which I transform to:
[10.91503, 48.185981, 11.554798, 48.40892199999999]
In Chrome for some reason the extent array contains infinite values:
extent = [ Infinity Infinity -Infinity -Infinity]
function CreateDriveMap(urlToXml)
{
var transformedCenter = ol.proj.transform(centerPos, 'EPSG:4326', 'EPSG:3857');
// PROJECTION
var projection = ol.proj.get('EPSG:3857');
// SOURCE
var source = new ol.source.OSM();
// TILE
// layer sources that provide pre-rendered, tiled images in grids
// that are organized by zoom levels for specific resolutions.
layer = new ol.layer.Tile({
source: source,
name: 'OpenStreetMap'
});
// VIEW
view = new ol.View({
center: transformedCenter,
zoom: 5
});
// STYLE
var style = {
'Point': [new ol.style.Style({
image: new ol.style.Circle({
fill: new ol.style.Fill({
color: 'rgba(255,255,0,0.4)'
}),
radius: 2,
stroke: new ol.style.Stroke({
color: '#f00',
width: 1
})
})
})],
'MultiPoint': [new ol.style.Style({
image: new ol.style.Circle({
fill: new ol.style.Fill({
color: 'rgba(255,0,255,0.5)'
}),
radius: 5,
stroke: new ol.style.Stroke({
color: '#f0f',
width: 1
})
})
})],
'LineString': [new ol.style.Style({
stroke: new ol.style.Stroke({
color: 'rgba(255,0,0,0.7)',
width: '3'
})
})],
'MultiLineString': [new ol.style.Style({
stroke: new ol.style.Stroke({
color: '#0f0',
width: 'rgba(255,0,0,0.7)'
})
})],
'Polygon': [new ol.style.Style({
fill: new ol.style.Fill({
color: 'rgba(0,255,255,0.5)'
}),
stroke: new ol.style.Stroke({
color: '#0ff',
width: 1
})
})],
'MultiPolygon': [new ol.style.Style({
fill: new ol.style.Fill({
color: 'rgba(0,0,255,0.5)'
}),
stroke: new ol.style.Stroke({
color: '#00f',
width: 1
})
})]
};
// Style Function
var styleFunction = function (feature, resolution) {
var featureStyleFunction = feature.getStyleFunction();
if (featureStyleFunction) {
return featureStyleFunction.call(feature, resolution);
} else {
return defaultStyle[feature.getGeometry().getType()];
}
};
// GPX layer
var vector = new ol.layer.Vector({
source: new ol.source.GPX({
projection: projection,
url: urlToXml //'data/gpx/fells_loop.gpx'
}),
style: function (feature, resolution) {
return style[feature.getGeometry().getType()];
}
});
// CREATE MAP
var map = new ol.Map({
// targeted div
target: 'map',
// the layers
layers: [layer, vector],
// the view
view: view,
//projection: new OpenLayers.Projection("EPSG:900913"),
projection: projection
// interactions
//interactions: ol.interaction.defaults().extend([dragAndDropInteraction])
});
//var View = map.getView();
// View.fitExtent(vector.getExtent(), /* @type {ol.Size} */ (map.getSize()));
// CENTER & PUT START MARKER, DOES NOT WORK
// ol.Layer.events.register("loadend", vector, function () {
// this.map.zoomToExtent(this.getDataExtent());
// var startPoint = this.features[0].geometry.components[0];
// layerMarkers.addMarker(new OpenLayers.Marker(new OpenLayers.LonLat(startPoint.x, startPoint.y), icon));
//});
// Add controls
var zoomslider = new ol.control.ZoomSlider();
map.addControl(zoomslider);
var scaleLine = new ol.control.ScaleLine();
map.addControl(scaleLine);
//FIT VIEW TO GPX
var extent = vector.getSource().getExtent();
var mapProjection = map.getView().getProjection();
ConvertedExtent = ol.proj.transformExtent(extent, 'EPSG:3857', 'EPSG:4326');
mapSize = map.getSize();
map.getView().fitExtent(extent, mapSize);
// STYLE FUNCTION
var stylefunction = function (feature, resolution) {
var featurestylefunction = feature.getstylefunction();
if (featurestylefunction) {
return featurestylefunction.call(feature, resolution);
} else {
return style[feature.getgeometry().gettype()];
}
};
// DRAG & DROP
var dragAndDropInteraction = new ol.interaction.DragAndDrop({
formatConstructors:
[
ol.format.GPX,
ol.format.GeoJSON,
ol.format.IGC,
ol.format.KML,
ol.format.TopoJSON
]
});
dragAndDropInteraction.on('addfeatures', function (event) {
var vectorSource = new ol.source.Vector({
features: event.features,
projection: event.projection
});
map.getLayers().push(new ol.layer.Vector({
source: vectorSource,
style: styleFunction
}));
var view = map.getView();
view.fitExtent(
vectorSource.getExtent(), /** @type {ol.Size} */ (map.getSize()));
});
}
Best Answer
I had a similar problem in version 3.8.2. I solved it by putting getExtent into the event:
In older version you just use
fitExtentinstead offit.