Add an option to remove feature silently in ol.source.Vector.

[ger-benjamin]

For #15642

Be able to remove a feature from vector source without triggering events. Useful to batch remove features.

[github-actions]

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[ahocevar]

I'm not sure this really fixes #15642. Please see my #15642 (comment).

[ahocevar]

Thanks for the contribution! From an API consistency perspective, it would make sense to add a removeFeatures() method, instead of adding a silent option to removeFeature(). Would you be able/willing to change this pull request accordingly? Then we had a sensible counterpart to addFeatures().

[ger-benjamin]

I've added a first simple version of removeFeatures/removeFeature.
removeFeature(feature) calls now this.removeFeatures([feature])
I'll check next steps on Monday. Have a nice weekend

[ahocevar]

I think going the other way around would be easier, something like

--- a/src/ol/source/Vector.js
+++ b/src/ol/source/Vector.js
@@ -1093,6 +1093,20 @@ class VectorSource extends Source {
     }
   }
 
+  removeFeatures(features) {
+    const removedFeatures = [];
+    for (let i = 0, ii = features.length; i < ii; ++i) {
+      const removedFeature = this.removeFeatureInternal(features[i]);
+      if (!removedFeature) {
+        continue;
+      }
+      removedFeatures.push(removedFeature);
+    }
+    if (removedFeatures.length > 0) {
+      this.changed();
+    }
+  }
+
   /**
    * Remove feature without firing a `change` event.
    * @param {FeatureType} feature Feature.
@@ -1113,9 +1127,11 @@ class VectorSource extends Source {
       delete this.idIndex_[id.toString()];
     }
     delete this.uidIndex_[featureKey];
-    this.dispatchEvent(
-      new VectorSourceEvent(VectorEventType.REMOVEFEATURE, feature),
-    );
+    if (this.hasListener(VectorEventType.REMOVEFEATURE)) {
+      this.dispatchEvent(
+        new VectorSourceEvent(VectorEventType.REMOVEFEATURE, feature),
+      );
+    }
     return feature;
   }

[ger-benjamin]

I've done the asked changes, but in this way, I've to duplicated the whole removeFeature code into the removeFeatures method. Are you sure that's the right thing to do ?

Or I can migrate:

      if (featureKey in this.nullGeometryFeatures_) {
        delete this.nullGeometryFeatures_[featureKey];
      } else {
        if (this.featuresRtree_) {
          this.featuresRtree_.remove(feature);
        }
      }

Into removeFeatureInternal. But Maybe it's useless in some direct call ?

Edit:
(2nd commit )I chose this solution: migrate a part into the removeFeatureInternal to avoid duplicated code. I've adapted the clean part too.

[ahocevar]

I have to apologize, I somehow managed to garble the diff I had posted above. I edited the post to show the correct diff.

That said, there should be no duplicated code. The change is essentially this new removeFeatures() method:

  removeFeatures(features) {
    const removedFeatures = [];
    for (let i = 0, ii = features.length; i < ii; ++i) {
      const removedFeature = this.removeFeatureInternal(features[i]);
      if (!removedFeature) {
        continue;
      }
      removedFeatures.push(removedFeature);
    }
    if (removedFeatures.length > 0) {
      this.changed();
    }
  }

And to make removeFeatureInternal() more efficient, events are only dispatched if someone listens to them:

    if (this.hasListener(VectorEventType.REMOVEFEATURE)) {
      this.dispatchEvent(
        new VectorSourceEvent(VectorEventType.REMOVEFEATURE, feature),
      );
    }

[ger-benjamin]

I've edited my post above.

But I can't call only edit removeFeatureInternal. Otherwise, this part about deleting nullGeometryFeatures_ and featuresRtree_.remove would be missing and break the feature

[ahocevar]

Looks like you have messed up something. This is what I had in mind: ahocevar@1e14403

[ger-benjamin]

Thanks, but again, If I only apply your changes, the removeFeatures method will miss this part:
https://github.com/openlayers/openlayers/blob/main/src/ol/source/Vector.js#L1083-L1088

And features will be only partially removed / broken.

[ahocevar]

Oh, sorry again, you're right. The code you marked above can simply be moved from removeFeature() to the top of removeFeatureInternal().

[ahocevar]

And that's what you did. Beautiful! Thanks for the contribution.