Remove vertex from geometry (polygon) in OpenLayers 5?

Question

I could able to remove the recent modified vertex of a feature using removePoint method of modify interaction, as well as using deleteCondition event of modify interaction. However, that is not what I am trying to achieve. The usecase for this this problem is as below.

I have modify interaction added on map. Now when user tries to modify a feature over map, I am highlighting the vertices, like this

so that user can directly go to these vertices and then do right click which will result in removal of vertex.

For this, I had to implement the contextmenu to handle the right click over map. But, now the challenge is to remove the received coordinate from the modifying geometry.

I tried to implement it as follows, with simple .splice() method on coordinate array of target geometry

if(this.modifyInteraction.features_.getLength() && this.modifyInteraction.features_.getArray()[0]){
           //Feature being modified
           let modifyft = this.modifyInteraction.features_.getArray()[0];
           let coord = modifyft.getGeometry().getCoordinates()[0];
           let foundIndex;
           for(var k = 0; k < coord.length; k++){
              if(coord[k][0] == rightClickedVertex.getGeometry().getCoordinates()[0] && 
              coord[k][1] == rightClickedVertex.getGeometry().getCoordinates()[1]){
                 foundIndex = k;
                 break;
              }
           }
           if(foundIndex && foundIndex > -1){
              modifyft.getGeometry().getCoordinates()[0].splice(foundIndex, 1);
              //nothing changes
           }
        }

is there any other way to remove the vertex of geometry being edited?

Suraj · Answer

Well, found the workaround quickly, I had to call the setCoordinates() method on the feature geometry I was trying to modify.

So in the above solution I updated just coordinates array and then updated the geometry like below

if(foundIndex && foundIndex > -1){
        coord.splice(foundIndex, 1);
      }
      // set back
      modifyft.getGeometry().setCoordinates([coord]);

This updates the feature over map by removing the vertex of geometry.

However, I feel this is not a recommended way to alter the geometry as this solution needs to access the features_ array of modifyinteraction which is not recommended.

So if anyone comes up with clean solution then welcome!

Remove vertex from geometry (polygon) in OpenLayers 5?

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