Collision icons jumping around

[harry-wood]

With the collisions map markers, in addition to this issue, these markers jump around randomly.

Is that deliberate?

[mvl22]

Currently there is jittering enabled, which causes this.

It's an attempt to deal with the issue that the original resolution of the data (which is an OS grid reference, not a lat-lon) means that often more than one collision happens in one place. As a result, Leaflet.js would only show one of them as they're in the same location.

https://www.cyclestreets.net/api/v2/collisions.locations/

See the jitter parameter. As noted there, the current implementation is recognised as not perfect. The solution is basically that we jitter once up-front rather than than on-request.

Another solution is clustering though personally in general I'm not a fan of that. I'd welcome views!