I'm working on a WordPress plugin where users can build a route map and show it on their site. In the admin panel it shows a preview of the existing route on the map, and also a marker they can drag to a new location that they want to add to the map.
The default zoom location for the map is set in Europe. But if they for example add a few stops in Australia, then only that part of the world is visible and you won't see the draggable icon anymore that is used to specify new locations, and that is a problem.
So I thought of fixing it with fitbounds, so it would always make the draggable marker and the already created route fit on the screen. The code I have does show all the locations on the map, but because I draw polylines between the visited locations, it somehow also draws a line to the draggable marker in Europe, which it shouldn't do because it's not part of the route.
You can see an example here -> http://jsfiddle.net/tijmen/HctvT/1/
Part of the code:
/* Draw lines between the markers */
function drawFlightPlan( flightPlanCoordinates ) {
var flightPath = new google.maps.Polyline({
path: flightPlanCoordinates,
geodesic: true,
strokeColor: "#ad1700",
strokeOpacity: 1.0,
strokeWeight: 2
});
flightPath.setMap( map );
fitBounds( flightPlanCoordinates );
}
/* Zoom the map so that all markers fit in the window */
function fitBounds( flightPlanCoordinates ) {
var bounds = new google.maps.LatLngBounds ();
/* Include this latlng value in europe, but I dont want a line going to that latng... */
var defaultLatlng = new google.maps.LatLng('52.378153', '4.899363');
flightPlanCoordinates.push( defaultLatlng );
for ( var i = 0, flightPlanLen = flightPlanCoordinates.length; i < flightPlanLen; i++ ) {
bounds.extend ( flightPlanCoordinates[i] );
}
map.fitBounds( bounds );
}
The lines between the markers in Australia are fine, but the line to Europe shouldn't be there (normally there would just be a different colored marker in Europe).
I don't really understand why there is a line going to Europe in the first place. The flightPath.setMap( map ); is run inside the drawFlightPlan function. And it's not untill the fitBounds function is that I add the latlng value for Europe to the flightPlanCoordinates array.
I searched for a way to remove a partial polyline, but I can't find anything about it that works. I know how to remove all the markers or polylines, but not a single polyline part. Is that even possible?
Any ideas or suggestion how to fix this, or is this something that cannot be fixed the way I want to?
initialize bounds with the LatLng in europe instead of pushing this LatLng into flightPlanCoordinates
http://jsfiddle.net/doktormolle/HctvT/4/
When you use a reference to an array as path for a polyline any changes to the array will affect the polyline.
Related
Im looking to "highlight" an area / specific region of the country Denmark, EXACTLY like it's seen here:
I've read that drawing a fill (or stroke) can be done by drawing lots of polygons to the map, example:
var bermudaTriangleCoords = [
new google.maps.LatLng(25.774252, -80.190262),
new google.maps.LatLng(18.466465, -66.118292),
new google.maps.LatLng(32.321384, -64.757370),
new google.maps.LatLng(25.774252, -80.190262)
];
var bermudaTriangle = new google.maps.Polygon({
paths: bermudaTriangleCoords,
strokeColor: '#FF0000',
strokeOpacity: 0.8,
strokeWeight: 2,
fillColor: '#FF0000',
fillOpacity: 0.35
});
How would I go about drawing an exact fill like the initial above link? Can I somehow get the longitude and latitude coordinates from the above fill? Or do some Google Maps GUI exist where I can draw and get the coordinates?
FIDDLE - Google maps demo
You cannot get the coordinates from the google maps link you referenced. The polygon (let's call it boundary) is part of the google maps application, but there is no API call to retrieve it.
For some countries such data is available though, as geojson files, or shapefiles. For example US Census organisation provide such data for respective US states, UK has "Ordinance Survey" organisation which also provide such data, but not for free, also there are some commercial organisations (For example here they have postal code boundaries for Denmark, but I cannot seem to find Denmark regions). So that's my first advice to you, try to search for something like: "Denmark regions boundaries shapefile" (if you know danish language, try in Danish, you might find some sites which I couldn't). Once you have the shapefile, you can use some convertor (e.g. mapshaper) to convert it to geojson format and then load the polygon on your map (here is an example on how to load world countries geojson to your map. You can load just one country/region, if your geojson contain coordinates just for that)
Alternatively, you can create your own very simple application, which allows you to draw on the map, and then print the coordinates to console. I have created a simple application for you, try to run it locally. After it loads, just click anywhere on the map to start drawing polygon and once you create it, watch javascript console for output of coordinates. You can then use the coordinates instead in your bermudaTriangleCoords):
function init() {
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 8,
center: new google.maps.LatLng(55.697683, 11.59711)
});
var drawing_manager = new google.maps.drawing.DrawingManager({
map: map,
drawingMode: google.maps.drawing.OverlayType.POLYGON
});
google.maps.event.addListener(drawing_manager, 'polygoncomplete', function(polygon) {
console.log("Polygon vertices coordinates following:");
polygon.getPath().forEach(function(el){
console.log(el.toString());
});
});
}
<script src="http://maps.google.com/maps/api/js?sensor=false&libraries=drawing&dummy=.js"></script>
<body style="margin:0px; padding:0px;" onload="init()">
<div id="map" style="height:400px; width:500px;"></div>
</body>
I use this tool to draw the kml points, and then I would just replace the points with those in the example above. You can change the kml setting to javascript, and then just copy the coordinates out.
http://www.birdtheme.org/useful/v3tool.html
It's really useful, hope it helps you.
I am working on GMap customization. I want a floating circle to move across a a Polyline. My question is that can we get all LatLng points in a Polyline after a specific interval for eg, all LatLng at interval of 100meters. My polyline code is:
/** polyline **/
var tpath = [
new google.maps.LatLng(15.508718,73.839337),
new google.maps.LatLng(15.511457,73.839165)
];
var travelPath = new google.maps.Polyline({
path : tpath,
map : map,
geodesic : true,
strokeColor : '#000',
strokeOpacity : 0.7,
strokeWeight : 1
});
i get only the end LatLng values. I want the values across the Polyline.
Thanks in advance.
You could use google.maps.geometry.spherical.computeHeading(startPoint, endPoint) to get the heading.
Then compute the distance with google.maps.geometry.spherical.computeDistanceBetween(startPoint, endPoint)
If the distance is 475m and you want to make ~100 jumps just do 475/round(475/100) to calculate the distance you want to move the circle each time. round(475/100) will give you how many times (iterations) you should move the circle.
Then you could use computeOffset(from:LatLng, distance:number, heading:number, radius?:number)
Then you can use computeOffset(circleCenter, distance, heading) to get the new cirecle center point in a for loop the amount of iterations calculated above. Don't forget to include a delay in your loop.
I don't know how to get it with google maps api but you can draw a line to get the points from a start and end manually. It's simple math for a drawing a line and calculate.
You can set On click listener on Polyline by using GoogleMap.OnPolylineClickListener, after it returns the polyline you click on.
List<LatLng> mPoints=polyline.getPoints();
be sure to make your polyline clickable by setting.
lineOptions.clickable(true);
I'm in a bit of a pickle here. I've set up a google maps object that shows airport locations using markers. I've even enabled clustering to a certain extent. The thing is that I need to include a filter which would allow users to:
Filter and show certain types of airports i.e by clicking on a corresponding check box
SHow markers within a certain distance from a central point. Like show all markers within a radius of # miles. A user can enter a value in a text field to see this or use a slider control.
I'm quite stuck with respect on starting this out - I need some help on this.
What you can do is draw your circle (in response to user input). Then draw the markers that fall within that bounds. Each time you redraw the circle, also redraw all the markers.
// draw a circle of appropriate radius
var circleOptions = {
center: destinationLatlng,
radius: 500, // or value from some formfield, in metres
fillColor: "#FF0000",
fillOpacity: 0.2,
strokeColor: "#FF0000",
strokeOpacity: 0.8,
strokeWeight: 1
};
var circle = new google.maps.Circle(circleOptions);
var bounds = circle.getBounds();
// loop over your markers, and only draw the ones that are within these bounds
for (var i = 0; i < arrMarkers.length; i++) {
if (bounds.contains(arrMarkers[i].getPosition())) {
// only do setMap if the marker wasn't already visible
if (arrMarkers[i].getVisible() != true) {
arrMarkers[i].setMap(map);
arrMarkers[i].setVisible(true);
}
} else {
// remove the ones that are not within the circle's bounds
arrMarkers[i].setMap(null);
arrMarkers[i].setVisible(false);
}
}
You'll notice I do both setMap and setVisible. This is so that I can then use getVisible to determine if I need to redo setMap (so avoiding unnecessary function calls to setMap - I think I had an issue with flickering).
All this should be within a function that happens in response to user input, e.g. when they submit the form that asks for the radius (or as they slide the slider). This should also maybe be called from within your initialize function (if you want to draw a circle at the very start as well).
Of course this assumes you actually want to display a circle on your map showing that radius; I find this useful. However if you don't, you can use exactly the same message, but just set the fillOpacity and strokeOpacity to 0.0.
Organize references to markers into categories when you add it to map:
var markers = { cat1: [...markers...], cat2: [...markers...] }
When user selects cirtain type - just set or unset map for that markers in markers.catN
I'm using Google maps V3, I searching for a listener to catch the movement (navigation) of the map, can I do that?
If yes, how can I do that and how can I know the size of movement in x and y ?
EDIT :
As I have a marker on the map, when I click on the marker a div is appeared in same position of the marker, but when I move the map, the maker moves in the same fashion, but the DIV is still in a fixed position, How can I move the div in the same way ?
The maps event 'bounds_changed' will help:
google.maps.event.addListener(map, 'bounds_changed', function () {
// whatsoever..., i.e.
boundsObject = map.getBounds();
});
It returns a bounds object consisting of two LatLng objects (NE and SW )whose values can be retrieved like:
neLatLngObject = boundsObject.getNorthEast();
swLatLngObject = boundsObject.getSouthWest();
// or the center of bounds:
ctrLatLngObject = boundsObject.getCenter();
To find the distance between two points look here: Calculate distance between two points in google maps V3
There are about 100 markers on a google map plus there is one special marker that needs to be visible. Currently, the markers around it hide it totally or partially when the map is zoomed out. I need that marker to be fully visible and I think keeping it on top of all other markers should do the trick. But I cannot find a way to modify its stacking order (z-index).
This is for Google Maps API 2.
For Google Maps API 3 use the setZIndex(zIndex:number) of the marker.
See:
http://code.google.com/apis/maps/documentation/javascript/reference.html#Marker
Use the zIndexProcess option in GMarkerOptions when you create the marker that you want on top. For example:
var pt = new GLatLng(42.2659, -83.74861);
var marker = new GMarker(pt, {zIndexProcess: function() { return 9999; }});
map.addOverlay(marker);
I believe the default is to have a z-index that is the latitude of the point of the marker, so this should be fairly safe at bringing a single marker to the front. Further, this was just a simple example; you can set the z-index of all your markers in whatever simple or complex way you want. Another example is to have two functions: one for special markers and one for the rest.
var pt1 = new GLatLng(42.2659, -83.74861);
var pt2 = new GLatLng(42.3000, -83.74000);
var marker1 = new GMarker(pt1, {zIndexProcess: specialMarker});
var marker2 = new GMarker(pt2, {zIndexProcess: normalMarker});
map.addOverlay(marker1);
map.addOverlay(marker2);
function specialMarker() {
return 9999;
}
function normalMarker() {
return Math.floor(Math.random()*1000);
}
Adding on to jhanifen's answer, if you want to get your one special marker to be on top of all the rest, set it's zIndex to google.maps.Marker.MAX_ZINDEX + 1. This will make sure that it is on top of any marker on the map.