I want to add heatmap on map. This is my code:
var mycanvas = document.getElementsByClassName('heatmap-canvas')
var imgData = mycanvas[1].toDataURL('image/png')
viewer.entities.add({
name: 'heatmap',
rectangle: new Cesium.RectangleGraphics({
coordinates: Cesium.Rectangle.fromDegrees(108.91125287994653, 34.16562697211902,
108.92125287994653, 34.17562697211902),
material: new Cesium.ImageMaterialProperty({
image: imgData,
// image: './favicon.ico',
transparent: true
})
// material: Cesium.Color.BLUE.withAlpha(0.5)
})
})
}
The first look is ok. But when zoomed in, the heat map will disappear. It's so strange.
Thank you for your help.
Map
Map (Zoomed)
Related
I am using Google Maps API JavaScript. My use case is I need to plot coordinates (lat, lng) on maps (create markers) and join them through polyline. The co-ordinates will be very close to each other so when I try to plot them, they get hidden behind the first marker. So I find out the center and try to zoom so that all markers will be visible on the map.
I used bounds to find the center but I am not able to zoom it to center co-ordinate. I used map.fitBounds(latlng); It fits the coordinate on the screen.
But what I want to achieve is to make polyline (connecting all co-ordinate) always horizontal and zoom it to center co-ordinate.
enter code herevar bounds = new google.maps.LatLngBounds();
for (i = 0; i < temp.length; i++) {
bounds.extend(temp[i]);
}
var latlng = bounds.getCenter();
map.setCenter(latlng);
As the coordinate will always be different, The polyline will be in any direction, but I always want to show it horizontally on the map.
what I get :
enter image description here
what i want to acheive:
enter image description here
Any suggestion will be appreciated.
Thanks in Advance.
I achieve something like this by using the following:
Use computeHeading() function of Geometry library to get the angle from your first to your last coordinate on the line. Make sure to add &libraries=geometry to your Maps JS script tag.
Once you get the heading, you can use the map.setHeading() function to change the angle of your view and after some testings,I can see that you can achieve the horizontal view by subtracting it to 90 degrees.
Here's the sample code and code snippet below:
function initMap() {
const map = new google.maps.Map(document.getElementById("map"), {
center: {
lat: 40.756795,
lng: -73.954298
},
zoom: 16,
tilt: 47.5,
mapId: "90f87356969d889c",
});
//array of your points
const markerCoordinates = [
{ lat: 40.758481, lng: -73.958269 },
{ lat:40.754649, lng: -73.949563 },
];
//creating marker from your points
for (let i = 0; i < markerCoordinates.length; i++) {
const marker = markerCoordinates[i];
new google.maps.Marker({
position:marker,
map,
});
}
//creating polyline from your points
const createdPolyline = new google.maps.Polyline({
path: markerCoordinates,
geodesic: true,
strokeColor: "#FF0000",
strokeOpacity: 1.0,
strokeWeight: 2,
});
createdPolyline.setMap(map);
//get the heading(angle) of the first coordinate from the last coordinate
const heading = google.maps.geometry.spherical.computeHeading(
markerCoordinates[0],
markerCoordinates[1]
)
//once you get the heading subtract it by 90 to get a horizontal view
map.setHeading(heading-90)
}
I am currently working on ionic native google maps building weather map . Basically i want to get LatLngBounds and zoom level while camera move then pass those data to url even shows data on map .
example every time when move map and zoom level, the url dynamically updates .
http://www.xxxxxxxx.net/map#lat=-25.87899&lng=-42.45117&zoom=4
My code :
getData(){
////Here should pass LatLngBounds in url ////
this.http.get('xxxxxxx/MetarJSON.php?bbox='','','',''' ,{},{}).then(data=>{
let DataJson = JSON.parse(data.data)
for (let datas of DataJson['features']) {
this.points.push({ lng: datas.geometry.coordinates[0], lat: datas.geometry.coordinates[1] });
}
for (let i = 0; i < DataJson.features.length; i++) {
let coords = DataJson.features[i].geometry.coordinates;
this.latLng = new LatLng(coords[1], coords[0]);
this.icoa = DataJson.features[i].properties.id
this.rawOb = DataJson.features[i].properties.rawOb
let fltcat = DataJson.features[i].properties.fltcat
let marker: Marker = this.map.addMarkerSync({
position: this.latLng,
title:fltcat,
icon: icons
})
}
})
}
loadMap() {
let mapOptions: GoogleMapOptions = {
camera: {
target: {
lat: 33.263,
lng: 44.232
},
zoom: 6,
}
};
this.map = GoogleMaps.create('map_canvas', mapOptions);
//// Here l get LatLngBounds but when l move map the lat and lng aren't update
let chec1= this.map.getVisibleRegion().farLeft.lat
let chec2= this.map.getVisibleRegion().farLeft.lng
console.log(chec1,chec2)
}
Ionic Google map native plugin Doc
l found solution while move map to update LatLngBounds . used GoogleMapsEvent constants
depending on doc , and he is working fine
this.map.on(GoogleMapsEvent.CAMERA_MOVE).subscribe(()=>{
let left= this.map.getVisibleRegion().northeast.lat
let leftbottom= this.map.getVisibleRegion().northeast.lng
let right= this.map.getVisibleRegion().southwest.lat
let rightbottom= this.map.getVisibleRegion().southwest.lng
console.log(left,leftbottom , right ,rightbottom )
})
Please i want to display a layer from GeoJSON file with openlayers 4.3.1 but the result (the vectorLayer variable) show a blank page. What am i missing?
The GeoJSON file is here https://gist.githubusercontent.com/abdounasser202/5d830738ad29e6395743530545bd322b/raw/0c34d9a1ced1879432318b6860c1c21e8e88ef04/quartiers_yaounde.geojson
Here is my JS code
var styles = {
'Polygon': new ol.style.Style({
stroke: new ol.style.Stroke({
color: 'grey',
width: 1
}),
fill: new ol.style.Fill({
color: 'rgba(0, 0, 255, 0.1)'
})
}),
};
var styleFunction = function(feature) {
return styles[feature.getGeometry().getType()];
};
var geojsonObject = 'https://gist.githubusercontent.com/abdounasser202/5d830738ad29e6395743530545bd322b/raw/0c34d9a1ced1879432318b6860c1c21e8e88ef04/quartiers_yaounde.geojson';
console.log("geodata >>> ", geojsonObject);
var vectorSource = new ol.source.Vector({
format: new ol.format.GeoJSON(),
url: geojsonObject
});
var vectorLayer = new ol.layer.Vector({
source: vectorSource,
style: styleFunction
});
var raster = new ol.layer.Tile({
source: new ol.source.OSM()
});
// var extent_degree = [11.4095, 3.71349, 11.5747, 3.9692];
var map = new ol.Map({
layers: [vectorLayer],
target: 'map',
view: new ol.View({
// projection: 'EPSG:4326',
center: ol.proj.fromLonLat([11.5021, 3.8480]),
zoom: 6
})
});
// ol.proj.get('EPSG:4326').setExtent(extent_degree)
var units = map.getView().getProjection().getUnits();
console.log("units >>> ", units);
var projections = map.getView().getProjection();
console.log("projections >>> ", projections);
According your code, you are styling Polygons, but no other geometry types. So you will see only Polygons on your map. Other geometry types will be invisible since they are not styled. The GeoJSON file does not contain Polygons, so indeed you won't see anything.
As far as I can see, the GeoJSON file contains only MultiPolygons. To make them visible, add a style for 'MultiPolygon' in the variable styles, or just change the string 'Polygon' in your code to 'MultiPolygon'.
I have converted multiple shapefiles to KML using the Shp2kml2 software from Zonums Solutions. I have made a map with the KML layers (of which I have imported to google docs to get the url). My map is found at: http://userpages.flemingc.on.ca/~catam/collab2.html
I have:
6 polygon KML layers,
1 point KML layer,
1 Google Fusion Table point layer
But when I try to click on a specific point, the pop-up information is that of the polygon which rests in the same place as the specific point.
My code is:
var map, layer2;
function initialize() {
var ontario = new google.maps.LatLng(49.2867873, -84.7493416);
var mapOptions = {
zoom: 5,
center: ontario
}
var infoWindow = new google.maps.InfoWindow();
var openInfoWindow = function (KMLevent) {
infoWindow.close();
infoWindow.setOptions(
{
content: KMLevent.featureData.infoWindowHtml,
position: KMLevent.latLng,
pixelOffset: KMLevent.pixelOffset
});
infoWindow.open(map);
};
var map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
var kmlOptions = {
suppressInfoWindows: true, // do not to display an info window when clicked
preserveViewport: false,
map: map
};
var urls = [
'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkajc2OGZTZDZBV0k&export=download', // SCHOOLS, NDP, LIBERAL, PC1, PC2, PC3,
'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkQzRSdVB1TVRseU0&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkWFlscVM5N01lSDQ&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkbHNSTjhCN1dLQTg&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkdnRoYnN1bnpubEU&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkaHg1WlNKdU1VWHc&export=download'
];
layer2 = new google.maps.FusionTablesLayer({
query: {
select: 'col9',
from: '1FzRSqRcxY37i7VtejqONHhAB-MrzFhakYSvZaIvo'
}
});
layer2.setMap(map);
urls.forEach(function(url) {
var layer = new google.maps.KmlLayer(url, kmlOptions);
layer.setMap(map);
KmlLayer.setZIndex(999);
google.maps.event.addListener(layer, "click", openInfoWindow);
});
}
//initialize();
google.maps.event.addDomListener(window, 'load', initialize);
It looks like the polygon layers are getting plotted over the points. Due to this even though you think you're clicking on the point the actual click event is generated on the polygon.
One solution would be to plot the polygons first followed by the points.
If that's not possible then you should set the z-index of the layer depending on whether it is a polygon or point.
kmlLayer.setZIndex(999);
The higher the z-index the higher the layer will be. I would suggest using a high z-index for the points while using a low z-index for the polygons. That should solve your problem.
The first option would be to move the url for points after the polygon urls. This should work without the need for z-index and will work without changing any of the code.
var urls = [
'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkQzRSdVB1TVRseU0&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkWFlscVM5N01lSDQ&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkbHNSTjhCN1dLQTg&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkdnRoYnN1bnpubEU&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkaHg1WlNKdU1VWHc&export=download',
'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkajc2OGZTZDZBV0k&export=download', // SCHOOLS, NDP, LIBERAL, PC1, PC2, PC3,
];
The second option is to remove the points url from the array and add that separately. First plot the polygons as shown below.
var urls = [
'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkQzRSdVB1TVRseU0&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkWFlscVM5N01lSDQ&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkbHNSTjhCN1dLQTg&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkdnRoYnN1bnpubEU&export=download', 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkaHg1WlNKdU1VWHc&export=download',
];
urls.forEach(function(url) {
var layer = new google.maps.KmlLayer(url, kmlOptions);
layer.setZIndex(10);
layer.setMap(map);
google.maps.event.addListener(layer, "click", openInfoWindow);
});
After this add the points layer
var pointsUrl = 'https://docs.google.com/uc?authuser=0&id=0B79b02nBK5vkajc2OGZTZDZBV0k&export=download'; // SCHOOLS, NDP, LIBERAL, PC1, PC2, PC3,
var layer = new google.maps.KmlLayer(url, kmlOptions);
layer.setZIndex(10);
layer.setMap(map);
google.maps.event.addListener(layer, "click", openInfoWindow);
I am using for a Google Maps Marker (V3) the icon in the following way:
var marker = new google.maps.Marker({
id: "theId",
icon: {
path: google.maps.SymbolPath.FORWARD_CLOSED_ARROW,
strokeColor: "green"
},
map: map,
title: "theTitle",
position: someLatitudeLongitude
});
Now after creating this marker I like to change the color run-time with a color panel.
Now this works perfectly for a polyline or polygon, but for the marker not quite well: it is changed but not real-time updated.
Code:
selectedShape.icon.strokeColor = color;
PROBLEM: Does not show color change on map. Only after saving and reloading the map, the correct color is shown.
For a polygon I use:
selectedShape.set('strokeColor', color);
This works fine.
So is there a set like operator for the marker or a partial refresh?
Thanks for any help.
Best regards,
Evert Wiesenekker
I would bind on an event where the color changes, then call marker.setIcon(icon_options) on the marker to pass in the new values.
I think what you need to do is 'refresh' the marker like this:
marker.getIcon().strokeColor = 'green';
marker.setMap(map);
Or you could do:
marker.setIcon({
path: google.maps.SymbolPath.FORWARD_CLOSED_ARROW,
strokeColor:'green'
});