/*
* This is part of Geomajas, a GIS framework, http://www.geomajas.org/.
*
* Copyright 2008-2011 Geosparc nv, http://www.geosparc.com/, Belgium.
*
* The program is available in open source according to the GNU Affero
* General Public License. All contributions in this program are covered
* by the Geomajas Contributors License Agreement. For full licensing
* details, see LICENSE.txt in the project root.
*/
package org.geomajas.layer.google.gwt.client;
import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.dom.client.Element;
import com.google.gwt.user.client.DOM;
import com.smartgwt.client.types.VerticalAlignment;
import org.geomajas.geometry.Coordinate;
import org.geomajas.global.Api;
import org.geomajas.gwt.client.gfx.PainterVisitor;
import org.geomajas.gwt.client.gfx.paintable.mapaddon.MapAddon;
import org.geomajas.gwt.client.map.event.MapViewChangedEvent;
import org.geomajas.gwt.client.map.event.MapViewChangedHandler;
import org.geomajas.gwt.client.spatial.Bbox;
import org.geomajas.gwt.client.widget.MapWidget;
/**
* <p>
* Map add-on that displays the Google attribution (copyright + terms of use) on the map. It can also show the actual
* Google map as opposed to the tiles that are calculated on the server. For normal Geomajas use this map should be
* hidden as it does not automatically scale to continuous zoom levels. This add-on requires the Google maps library !
* </p>
* <p>
* This MapAddon does not allow center positioning. Also it takes in the whole width of the map, so setting the
* horizontal alignment is of little use. By default, this MapAddon will be placed 20 pixels from the bottom of the map.
* </p>
*
* @author Jan De Moerloose
* @since 1.8.0
*/
@Api
public class GoogleAddon extends MapAddon implements MapViewChangedHandler {
private static final double HALF_CIRCLE = 180.0;
private MapWidget map;
private JavaScriptObject googleMap;
private MapType type;
private boolean showMap;
private static final double MERCATOR_WIDTH = Math.PI * 6378137.0;
/**
* Google map types as defined by the API.
*/
public enum MapType {
NORMAL, SATELLITE, HYBRID, PHYSICAL
}
// Constructor:
/**
* Create the Google addon to assure the copyright details are displayed on the map.
*
* @param id element id
* @param map map widget to display copyright on
* @param type map type
* @param showMap should the map be visible?
*/
@Api
public GoogleAddon(String id, MapWidget map, MapType type, boolean showMap) {
super(id, 0, 0);
this.map = map;
this.type = type;
this.showMap = showMap;
this.map.getMapModel().getMapView().addMapViewChangedHandler(this);
// Default placement:
setVerticalAlignment(VerticalAlignment.BOTTOM);
setVerticalMargin(20);
}
// MapAddon implementation:
public void accept(PainterVisitor visitor, Object group, Bbox bounds, boolean recursive) {
if (googleMap == null) {
// create as first child of raster group
map.getRasterContext().drawGroup(null, this);
String id = map.getRasterContext().getId(this);
String graphicsId = map.getVectorContext().getId();
googleMap = createGoogleMap(id, graphicsId, type.name(), showMap, getVerticalMargin(),
getHorizontalMargin(), getVerticalAlignmentString());
}
}
public void onDraw() {
}
public void onRemove() {
String id = map.getRasterContext().getId(this);
// Remove the terms of use:
Element element = DOM.getElementById(id + "-googleAddon");
if (element != null) {
Element parent = element.getParentElement();
parent.removeChild(element);
}
// Remove the Google map too:
element = DOM.getElementById(id);
if (element != null) {
Element parent = element.getParentElement();
parent.removeChild(element);
}
googleMap = null;
}
public void onMapViewChanged(MapViewChangedEvent event) {
// assume google coordinates here
if (googleMap != null) {
Bbox latLon = convertToLatLon(event.getBounds());
fitGoogleMapBounds(googleMap, latLon.getX(), latLon.getY(), latLon.getMaxX(), latLon.getMaxY());
}
}
// ------------------------------------------------------------------------
// Private methods:
// ------------------------------------------------------------------------
private native JavaScriptObject createGoogleMap(String mapId, String graphicsId, String mapType, boolean showMap,
int verticalMargin, int horizontalMargin, String verticalAlignment)
/*-{
var mapDiv = $doc.getElementById(mapId);
var map = new $wnd.GMap2(mapDiv);
if (mapType == "NORMAL") {
map.setMapType($wnd.G_NORMAL_MAP);
} else if (mapType == "SATELLITE") {
map.setMapType($wnd.G_SATELLITE_MAP);
} else if (mapType == "HYBRID") {
map.setMapType($wnd.G_HYBRID_MAP);
} else if (mapType == "PHYSICAL") {
map.setMapType($wnd.G_PHYSICAL_MAP);
}
if(!showMap) {
mapDiv.style.visibility = "hidden";
}
var graphics = $doc.getElementById(graphicsId);
var group = $doc.createElement("div");
group.setAttribute("id", mapId + "-googleAddon");
graphics.appendChild(group);
var termsOfUse = mapDiv.lastChild;
mapDiv.removeChild(termsOfUse);
group.appendChild(termsOfUse);
if ("top" == verticalAlignment) {
termsOfUse.style.top = verticalMargin + "px";
} else {
termsOfUse.style.bottom = verticalMargin + "px";
}
termsOfUse.style.marginRight = horizontalMargin + "px";
var poweredBy = mapDiv.lastChild;
mapDiv.removeChild(poweredBy);
group.appendChild(poweredBy);
if ("top" == verticalAlignment) {
poweredBy.style.top = verticalMargin + "px";
} else {
poweredBy.style.bottom = verticalMargin + "px";
}
poweredBy.style.marginLeft = horizontalMargin + "px";
return map;
}-*/;
private native void fitGoogleMapBounds(JavaScriptObject map, double xmin, double ymin, double xmax, double ymax)
/*-{
var sw = new $wnd.GLatLng(xmin, ymin);
var ne = new $wnd.GLatLng(xmax, ymax);
var bounds = new $wnd.GLatLngBounds(sw,ne);
map.setCenter(bounds.getCenter(), map.getBoundsZoomLevel(bounds));
}-*/;
private Bbox convertToLatLon(Bbox bounds) {
// convert corners
Coordinate orig = convertToLatLon(bounds.getOrigin());
Coordinate end = convertToLatLon(bounds.getEndPoint());
return new Bbox(orig.getX(), orig.getY(), end.getX() - orig.getX(), end.getY() - orig.getY());
}
private Coordinate convertToLatLon(Coordinate coordinate) {
double lat = (coordinate.getY() / MERCATOR_WIDTH) * HALF_CIRCLE;
double lon = (coordinate.getX() / MERCATOR_WIDTH) * HALF_CIRCLE;
lat = HALF_CIRCLE / Math.PI * (2 * Math.atan(Math.exp(lat * Math.PI / HALF_CIRCLE)) - Math.PI / 2.0);
return new Coordinate(lat, lon);
}
private String getVerticalAlignmentString() {
// No center position, just top and bottom:
VerticalAlignment align = getVerticalAlignment();
if (align != null && align.equals(VerticalAlignment.TOP)) {
return "top";
}
return "bottom";
}
}