title: Mapbox GL sort overlapping circles by radius
body: <p>I'm trying to display circles with Mapbox GL that are very close and sometimes they overlap. I would like the circles to overlap according to their size (radius), from the biggest to the smallest, so that they will all be visible on map. Is there a way to do it?<br>
  <br>I made a simple example to illustrate the problem I'm facing. One can see that the circle with the biggest radius is on top of the others.</p>
  
  <pre><code>var data = {
    "type": "FeatureCollection",
    "features": [{
      "type": "Feature",
      "properties": {
        "value": 2
      },
      "geometry": {
        "type": "Point",
        "coordinates": [-31.640625,
          31.952162238024975
        ]
      }
    }, {
      "type": "Feature",
      "properties": {
        "value": 5
      },
      "geometry": {
        "type": "Point",
        "coordinates": [-31.640625,
          31.952162238024975
        ]
      }
    }, {
      "type": "Feature",
      "properties": {
        "value": 10
      },
      "geometry": {
        "type": "Point",
        "coordinates": [-31.640625,
          31.952162238024975
        ]
      }
    }]
  };
  
  var map = new mapboxgl.Map({
    container: 'map',
    style: 'mapbox://styles/mapbox/dark-v9',
    center: [-30, 33],
    zoom: 3
  });
  
  map.on("load", function() {
  
    map.addSource('point', {
      "type": "geojson",
      "data": data
    });
  
    map.addLayer({
      "id": "point",
      "source": "point",
      "type": "circle",
      "paint": {
        "circle-color": "#FFFF00",
        "circle-stroke-width": 1,
        "circle-stroke-color": "#000",
        "circle-radius": {
          property: 'value',
          stops: [
            [2, 10],
            [10, 30],
          ]
        }
      }
    });
  
  })
  </code></pre>
  
  <p>Complete example in JSFiddle:</p>
  
  <p><a href="https://jsfiddle.net/zorgdevalmont/5ch1aj52/3/" rel="nofollow noreferrer">https://jsfiddle.net/zorgdevalmont/5ch1aj52/3/</a></p>
  
  <p>Many thanks.</p>