Layer visibility in OpenLayers

[ymoisan]

Hi. I'm trying to find my way to implementing the nice list of tickboxes one can see in the PMTiles viewer to allow selecting layers for display. All I find are references to the MapLibre implementation but we're using OpenLayers. Any hint or suggestion for a path forward?

Thanx for this very cool project.

[bdon]

(moved to discussion)

There are OL utility classes at https://github.com/protomaps/PMTiles/tree/main/openlayers , but those simply load tiles into the OL data model, the tickbox UI is something to be implemented within OL and is not specific to PMTiles.

[ymoisan]

Thank you for your answer. I understand this isn't a PMTiles thing. It seems to me most PMTiles functionality is better served/handled in Leaflet or MapLibre than in OL, which is totally fine. (I' far from an OL expert, you'll have sensed).

FWIW I came up with this clumsy styling function which half works :

     function(feature) {
              const geometryType = feature.getGeometry().getType();
              const featureLayer  = feature.properties_.layer;
              const combinedCondition = `${geometryType}_${featureLayer}`;
              switch (combinedCondition) {
                case "LineString_boundaries":
                    return commonStyle;
                  break;
                case "Polygon_earth":
                  return earthStyleModified;
                  break; 
                case "Polygon_water":
                  return water;
                  break; 
                default:
                  return null;
              }

It half works probably because of the computation involved in iterating over all features. Just to be sure : that tickbox in the viewer does not involve such computations ?

Cheers

[bdon]

Layers in MVT tiles can be heterogenous so the MapLibre style and likely the OL style will need to create 3 styles for point, line and polygon for every layer.