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Question

With the MarkerCluster algorithm, it's possible to cluster the nearby markers together, so the map is visually very acceptable.

however, I found that the performance and the response of leaflet map decrease with the number of markers inside it.

I still don't understand it but I found people talking about Server-side clustering solution instead of client-side clustering.

This durable module project is a solution for big numbers of markers that uses this concept ( Server-side clustering ) in leaflet map.

My questions are:

how it is done in leaflet map?
how to make this solution in python at folium maps?

Answer 1

Server-side clustering can be accomplished with XHR requests.

The simplest approach would be to divide your map into squares, and have it switch between single-feature layers and substitute geoJSON/JSON layers using a MAP.on('zoomend', function(e){}); event.

In an example, if jQuery is available, you can do $.getJSON(SERVER_SIDE_URL, {VARIABLE: 'VALUE'}, function(data){}); on zoomend. Here the anonymous function will carry response data. You can use this data to either create a substitute LayerGroup, or a single Layer, while keeping track of and destroying its predicate.

The server's side will need to have access to the full dataset, and be able to either provide JSON for a single feature abstracting those nearby, or a set of features within the radius/square radius of a placeholder.

That's the abstract of one option. Alternatively, there may be market-ready solutions. But writing your own should produce a more efficient solution for such a simple task.

Answer 2

I find an Opensource solution for leaflet and Mapbox .

it is the SuperCluster project created by the owner of leaflet. it is Server-Side Clustring solution with node.js and Client-Side Clustring with MapBox.

the concept of these algorithme is explained here