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HERE Traffic incidents integration in Leaflet.js

Background:
I'm currently integrating HERE maps into our web-based application. I'm trying both - HERE provided Javascript API and Leaflet at the same time to find the best approach for our use-case.
While JavaScript API provided by HERE maps is OK, rendering wise Leaflet performs much better when using raster tiles.
Issue:
It would be fine by me to use raster tiles + leaflet, but our application also needs to display traffic incidents data.
Traffic incident data is provided by HERE in JSON and XML formats (Documentation link, Example JSON). They provide [Z]/[X]/[Y], quadkey, prox, bbox, or corridor filters which can be used to retrieve filtered data set.
I've tried using [Z]/[X]/[Y] addressing with custom L.TileLayer implementation which loads appropriate JSON, converts it to GeoJSON and displays GeoJSON on map. However that approach is very inefficient and significant performance drop is visible.
Question:
Maybe anyone has already solved this issue and could share any insights on how the HERE traffic incidents could be shown on Leaflet map without encountering performance issues?

I created the following script, which works without any performance issues:
var fg = L.featureGroup().addTo(map);
function loadTraffic(data) {
fg.clearLayers();
var d = data.TRAFFICITEMS.TRAFFICITEM.map((r) => {
var latlngs = [];
if (r.LOCATION.GEOLOC) {
if (r.LOCATION.GEOLOC.ORIGIN) {
latlngs.push(L.latLng(r.LOCATION.GEOLOC.ORIGIN.LATITUDE, r.LOCATION.GEOLOC.ORIGIN.LONGITUDE));
}
if (r.LOCATION.GEOLOC.TO) {
if (L.Util.isArray(r.LOCATION.GEOLOC.TO)) {
r.LOCATION.GEOLOC.TO.forEach((latlng) => {
latlngs.push(L.latLng(latlng.LATITUDE, latlng.LONGITUDE));
})
} else {
latlngs.push(L.latLng(r.LOCATION.GEOLOC.TO.LATITUDE, r.LOCATION.GEOLOC.TO.LONGITUDE));
}
}
}
var desc = r.TRAFFICITEMDESCRIPTION.find(x => x.TYPE === "short_desc").content;
return {
latlngs,
desc
}
})
console.log(d);
d.forEach((road)=>{
L.polyline(road.latlngs,{color: 'red'}).addTo(fg).bindPopup(road.desc);
});
map.fitBounds(fg.getBounds())
}
If this script is not working for you, please share your json file.

Ok, so I've found a solution for this task. Apparently I was on a good path, I only needed to optimize my implementation.
What I had to do to achieve appropriate performance is:
Create custom CircleMarker extension which would draw custom icon on canvas
Create JS worker which would fetch the data from a given URL, transform it to GeoJSON and return GeoJSON to it's listener
Create custom GridLayer implementation, which, in fetchTile function, creates worker instance, passes it a link with appropriate [Z]/[X]/[Y] coordinates already set, adds listener, which listens for worker's done event and returns empty tile
On worker's done event, custom GridLayer implementation creates GeoJSON layer, adds it to the dictionary with coordinates as a key and, if zoom level is still the same - adds that layer to the map
Add zoomend observer on a map, which removes any layers that does not match current zoom level from the map
Now the map is definitely usable and works way faster than original HERE JS API.
P.S. Sorry, but I can't share the implementation itself due to our company policies.

usage of querySourceFeatures and setData

I'm developping a map using mapbox gl js, my issue is the following:
I have 1 source and I apply 1 setData on this source with a geojson collection of points -> fine
I want to update one position for one feature (point) of this featurecollection
I do querySourceFeatures and I get an array of features -> fine
I detect the feature I want to modify and I modify the lat-long accordingly -> fine
I would like to apply the whole setData with the modify feature to redraw but ...
Here is the problem, how do I go from the array of features (one is modified) to a feature collection compatible with setData ... ?
I'm confused why (or what) there is not a straight path to do that ... What do I miss here?
can you help me please?
thanks,
Olivier

finally, I rebuild the featureCollection "manually" in a separate function ... I though it would not be an optimized solution but at the end, reveals quite straight ...
function build_featureCollection_from_array(parray) {
lv_fc = {};
lv_fc.type = "FeatureCollection";
lv_fc.features = parray;
return lv_fc;
}

view panoramic image on google map

function initPano() {
// Set up Street View and initially set it visible. Register the
// custom panorama provider function. Set the StreetView to display
// the custom panorama 'reception' which we check for below.
var panorama = new google.maps.StreetViewPanorama(
document.getElementById('map'), {
pano: 'reception',
visible: true,
panoProvider: getCustomPanorama
});
}
// Return a pano image given the panoID.
function getCustomPanoramaTileUrl(pano, zoom, tileX, tileY) {
// Note: robust custom panorama methods would require tiled pano data.
// Here we're just using a single tile, set to the tile size and equal
// to the pano "world" size.
return 'http://bestofdiscus.gr/portals/0/Discus-Header-WR.jpg';
}
function getCustomPanorama(pano, zoom, tileX, tileY) {
if (pano === 'reception') {
return {
location: {
pano: 'reception',
description: 'Google Sydney - Reception'
},
links: [],
// The text for the copyright control.
copyright: 'Imagery (c) 2010 Google',
// The definition of the tiles for this panorama.
tiles: {
tileSize: new google.maps.Size(1024, 512),
worldSize: new google.maps.Size(1024, 512),
centerHeading: 105,
getTileUrl: getCustomPanoramaTileUrl
}
};
}
}
In this block of code, i don't understand the parameters :pano, zoom, tileX, tileY in the function getCustomPanoramaTileUrl. I understand that, without using these parameter, the function will return an url of image.
my question is:
1/What do these parameters use for and how to use it ?
2/What is a pano ID (i have been searching for it a lot but still can not understand)

What are you talking about?
You may be thinking, "why is my question downvoted?" (PS: I didn't do it!). When asking a question, slapping random code with no context whatsoever will leave anyone trying to help you just as lost as you.
Though the code is useful, your question is missing important information:
What technologies are you using? Any APIs?
What have you tried?
Where is that code from?
Any links to any documentation? What is the context?
Before making a question, always make sure to read the following page https://stackoverflow.com/help/how-to-ask
Your code, where does it come from?
After doing some digging and some research I was able to find that your code is actually a piece of code from the Google Documentation, Custom Street View panoramas.
With this in mind Google has some documentation on the matter that will help you understand what is going on with your code:
https://developers.google.com/maps/documentation/javascript/streetview#TilingPanoramas
I read the documentation, but I still don't get it!
Although Google talks about Custom Panoramas with multiple views, the example provided is too simple to illustrate the full potential of the resources Google provides you.
Now, regarding your specific question...
What are pano, zoom, tileX, tileY used for?
In the code example that you provided, they are used for... nothing. You could literally remove them from getCustomPanoramaTileUrl and the code would still work.
So, what are they used for? Well, according to the References Documentation for StreetView, these parameters have the following objective:
Gets the tile image URL for the specified tile. pano is the panorama
ID of the Street View tile. tileZoom is the zoom level of the tile.
tileX is the x-coordinate of the tile. tileY is the y-coordinate of
the tile. Returns the URL for the tile image.
Now, if this is still, confusing, I will try to explain.
Custom panoramas are sets of images, put together, like in the image bellow:
When using a real panoramic view, you want to pass a set of images, and the StreetView object needs to know which set of images you are referring to (panoId), at which zoom level (zoom) and inside the set, the X and Y positions of the image you are currently seeing (tileX and tileY).
In the example you provided, since it is extremely simple, none of this is used because you always return the same image no matter what. But in a more complex example, that uses a set of images, this information would be crucial to let the StreetView know where you are looking at in order to display the correct image.
Hope it helps!

How Can I animate Bing map pushpins based on a live GPS feed

I have looked over the bing maps documentation trying to find an answer to my question. I would prefer to do everything using the bing maps api and not have to add a third party library if possible.
Question: How can I animate a pushpin to make a smooth transition from one set of gps coordinate(longitude/latitude) to another in order to simulate smooth movement of a Pushpin on Bing maps?
Question: can deleting an entire object out of the map.entities array waste enough resources to cause performance issues? If so how can I change the pushpin latitude and longitude properties without deleting the entire object?
Sample code of trying to change the pushpins properties without deleting the object out of the array. This code does not work… I am unsure why it is not working?
map.entities.get(theIndexOfThePushPin)._location.latitude = newLat;
map.entities.get(theIndexOfThePushPin)._location.longitude = newLon;
I create a pushpin like so - This works fine
map.entities.push(new Microsoft.Maps.Pushpin(new Microsoft.Maps.Location(lat, lon), {
text: text,
visible: true,
textOffset: new Microsoft.Maps.Point(0, 5)
}));
Pseudo code for my recursive angular $http call
function BusMoveGPSRefresh() {
$http.get(resourceURL)
.then(function (data) {
if ('if pushpins have not been created') {
//create pushpins...
}
} else {
//delete pushpins out of the array and then recreate them
//with updated lon/lat. Or just update existing objects lon/lat properties if possible?
}
}
BusMoveGPSRefresh();//after everything is done then go get more info and start again. recursion...
}, function (reason) {// if fail than do
console.log(reason);
console.log("This Is not Working!!! Dang!!");
});
}
Any insight into the problem would be greatly appreciated! Thanks!

I could not find a simple answer for adding animation. I did find a site that gave a step by step tutorial on a more in-depth answer on how to animate pushpins.
Answer: 1 -- tutorial on how to animate bing map pushpins
https://blogs.bing.com/maps/2014/08/07/bring-your-maps-to-life-creating-animations-with-bing-maps-javascript/
Answer: 2 -- this is how to update the pushpin location without deleting the pushpin object out of the entities array.
Instead of deleting the entire pushpin object find the pushpin index and then use the property "setLocation()" and then add a new location.
//check to make sure that the lat and lon have
//changed if it is still the same location do nothing. else update
if (map.entities.get(indexOfPushpin).getLocation().latitude != lat
|| map.entities.get(indexOfPushpin).getLocation().longitude != lon) {
map.entities.get(indexOfPushpin).setLocation(new Microsoft.Maps.Location(lat, lon));
}

google Maps: $.goMap() with custom overlayMapType

First: I try to remake a Website called regionalkarten.com
It's a German publisher of Maps. This page uses the Google API v2 to show our custom maps.
My Job is to update the Page to API v3.
Now I found the jQuery GoMap Plugin and I try to use it, but it doesn't seem to support custom maps.
I tried to define a Overly with the custom Map
var ehsTypeBOptions =
{
getTileUrl: function(coord, zoom)
{
var x = coord.x;
var y = coord.y;
return "http://regionalkarten.com/_map/ehs_village_maps/is_maps/z"+zoom+"/"+coord.y+"/"+coord.x+".png";
},
tileSize: new google.maps.Size(256, 256),
};
and load it into the map with:
map.overlayMapTypes.insertAt(0, new google.maps.ImageMapType(ehsTypeBOptions));
That works fine without GoMap. So I tried:
$.goMap.overlayMapTypes.insertAt(0, new google.maps.ImageMapType(ehsTypeBOptions));
and guess what, it didn't work :(
GoMaps Webpage and Google aren't very helpful. Keep in mind that I have to load the custom map into an overlay. I need the real google maps behind the overlay because our maps are not gapless.
I hope you got some ideas or experience with GoMap.
Thank you.

$.goMap does not return the native google.maps.Map-instance, so you can't use the Maps-API-methods there.
The google.maps.Map-instance may be accessed via $.goMap.map .
Beyond that: I would suggest not to use this library, there haven't been any updates since 1 year, and this all can be done without any additional library.
More important: before you continue working with ImageMapType, this is not the right MapType for you, because it appears that the TileServer don't serve tiles for the complete world.
When the user pans or zooms so that a area is in viewport where no tile is available, this area would be shown as a gray space. You better use a Overlay MapType and set the background-image of the overlays to the TileUrl(additionally you may use a condition that checks if a Tile is available at all to reduce unnecessary request to the tile-server)