Repro program here: https://codepen.io/theGrahamScanlon/pen/vYGEVKa (make sure to update the auth token) If the datasource that loads in the below geojson has the 'cluster' property set to true, the datasource fails to load with the exception: "Cannot read property '0' of undefined @ atlas.min.js:2509". The datasource loads in fine when the 'cluster' property is set to false var geoJson = { type: "FeatureCollection", features: [ { type: "Feature", geometry: { type: "GeometryCollection", geometries: [ { type: "Point", coordinates: [2, 2] }, { type: "Point", coordinates: [1, 1] } ] }, properties: {} }] }; -Graham

GeometryCollections don't support clustering. Only individual points support clustering.

Azure Maps: Bug when parsing a GeoJson GeometryCollection when a DataSource's cluster property is true

Accepted answer

rbrundritt 18,061 Reputation points Microsoft Employee

2020-08-14T16:01:15.927+00:00

GeometryCollections don't support clustering. Only individual points support clustering.
Please sign in to rate this answer.
Anonymous

2020-08-14T16:48:57.08+00:00

Thanks,

It would be nice if that were reflected somewhere. I was unable to find any shape exception in the clustering docs .

The original issue is clarified so I'll accept the answer

rbrundritt 18,061 Reputation points Microsoft Employee

2020-08-14T22:05:26.667+00:00

The title of the doc is "Clustering point data" and throughout it says "point data" and "data points".

Additionally, GeometryCollections are rarely used. Out of the thousands of GIS customers I've worked with over the past decade and a half, I've only come across a half a dozen or so who had GeometryCollections in their test data, and only one in production data.

Anonymous

2020-08-17T18:09:24.003+00:00

Maybe using the LineString was poor judgement in my example

If the GeometryCollection contains both Geometries of type Point, the map still fails to render the Point data. That is 100% "point data".

The issue is with Geometry Collections and not "Point Data"

Your disregard of the issue because Geometry Collections are rarely used is concerning. Adding in a note to the doc saying Geometry Collections are not supported for clustered point data make sense because Geometry Collections are supported in other parts of the Web sdk without fail. You'd expect GeoJSON that works with part of the web sdk to work with all the other parts as well

QuantumCache 20,266 Reputation points

2020-08-17T20:30:06.893+00:00

Hello anonymous user , Thanks for the valuable feedback!

We are working on enhancing the document to avoid such issues in the future.

Please stay tuned for further updates from our side. Sorry for the inconvenience caused.

rbrundritt 18,061 Reputation points Microsoft Employee

2020-08-17T20:45:48.813+00:00

A GeometryCollection represents a complex geometry with a collection of child geometries, Clustering doesn't work on LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, or GeometryCollection's, only on features that have a single Point geometry. This isn't limited to Azure Maps, this is how point clustering works in general, across all other platforms too.

Note that a GeometryCollection represents a single complex shape with multiple child geometries. In GeoJSON this would be passed into a single Feature.

Clustering looks at individual points and groups them together if they are close together into a cluster. This can't logically be done with a GeometryCollection as you could easily run into the situation where points within a single GeometryCollection fall into different clusters, or not in a cluster at all. At which point, each point would have to be treated as individual features which goes against the purpose of using a GeometryCollection.
Sign in to comment

Use comments to ask for clarification, additional information, or improvements to the question.

Share via

Azure Maps: Bug when parsing a GeoJson GeometryCollection when a DataSource's cluster property is true

0 additional answers

Your answer