protobuf vectorTileLayerStyles: filter out some elements

[bagage]

I am using a protobuf tile server which returns me cities, and I'd like to draw only some of them, for instance the one starting with letter A (could be anything else actually).

Yet I am using:

L.vectorGrid.protobuf(
  tilesServerUrl,
  vectorTileLayerStyles: {
    "cities": (properties, zoom) => {
      if (properties.name.indexOf('a') !== 0) {
        return {
          fillOpacity: 0,
          stroke: false,
          fill: false,
          opacity: 0,
          weight: 0,
        };
      } else {
        return {
          weight: 2,
          color: 'red',
          fill: true,
          fillOpacity: 0.8
        };
      }
    }
  }
);

~~My issue is, I believe, that all my cities are still drawn and that makes the map scroll very laggy because there are too much points on the map. ~~ Actually vectorGrid by itself is fine, it is combined with angular that the issue rises really. But filtering out points would solve the issue so still keeping this issue open for my part.

Thus I'd like to totally filter out the cities not matching given criteria. Is that possible?

[jamesurobertson]

For anyone else finding this page you should be able to return an empty array [] and it wont draw anything on the map.

[Matteomt]

For anyone else finding this page you should be able to return an empty array [] and it wont draw anything on the map.

Could you please clarify which function should return the empty array?

I tried the functions mapped under vectorTileLayerStyles, but it does not work. Also, the function typing does not seem to allow returning an array.

I also tried the filter option that I can find in the type, but that doesn't work either: the function doesn't even get called to evaluate the filter condition (see issue: #285 ).