implement remove edge from clustering

[micahstubbs]

remove edge from clustering

steps to reproduce

cd visjs-network
# run a local server
live-server

then visit the example (you may need to update the port to match the port that your local server is running on)
http://127.0.0.1:51702/examples/network/other/clusteringByZoom.html

open the browser console (cmd+j on a mac) and notice the error message:

[JHeinzde]

Hello Micah,

I would consider trying to implement this, but I am relatively unexperienced, so it may take a while for me to implement this. Let me know your thoughts on this.

Best Regards,

Jonathan

[micahstubbs]

@JHeinzde go for it! I'd be happy to review a PR that fixes this bug.

[Tyler-Maclachlan]

@micahstubbs @JHeinzde Hey guys, I'm getting this error a lot with clusters, can someone point me in the right direction to fix it, or is this almost implemented?

[micahstubbs]

@Tyler-Maclachlan perhaps so. can you share a screenshot or some error text from the error that you are seeing? That will help us know how best to help 😄

[Tyler-Maclachlan]

@micahstubbs,

I had the same error as in the screenshot above. Here is how I've fixed it for my project:

if (shouldBeClustered === this._isClusteredEdge(edge.id)) {
        return // all is well
      }

      if (shouldBeClustered) {
        // add edge to clustering
        let clusterFrom = this._getClusterNodeForNode(edge.fromId)
        if (clusterFrom !== undefined) {
          this._clusterEdges(this.body.nodes[edge.fromId], edge, clusterFrom)
        }

        let clusterTo = this._getClusterNodeForNode(edge.toId)
        if (clusterTo !== undefined) {
          this._clusterEdges(this.body.nodes[edge.toId], edge, clusterTo)
        }

        // TODO: check that it works for both edges clustered
        //       (This might be paranoia)
      } else {
        delete this._clusterEdges[edgeId]
        this._restoreEdge(edge)
        // This should not be happening, the state should
        // be properly updated at this point.
        //
        // If it *is* reached during normal operation, then we have to implement
        // undo clustering for this edge here.
        // throw new Error('remove edge from clustering not implemented!')
      }

[micahstubbs]

ah hah! thanks for that snippet @Tyler-Maclachlan. I'll try this out locally and see if I can reproduce the fix.

[Tyler-Maclachlan]

@micahstubbs cool, will you let me know if you merge these changes and my previous PR #66, because we've currently forked the library to carry on working.