HARP-12145: Fix gaps along the antimeridian.

This change introduces the flag `roundUpCoordinatesIfNeeded` to
the `VectorTileDataSource`. When the flag is enabled the decoder
is allowed to adjust the coordinates of liens and polygons close
to the antimeridian to avoid gaps.

Currently the flag is enabled only when using the HERE vector service.

Signed-off-by: Roberto Raggi <roberto.raggi@here.com>

@here/harp-vectortile-datasource/lib/OmvDecoderDefs.ts

@@ -206,6 +206,8 @@ export interface OmvDecoderOptions {
     politicalView?: string;
 
     enableElevationOverlay?: boolean;
+
+    roundUpCoordinatesIfNeeded?: boolean;
 }
 
 /**

@here/harp-vectortile-datasource/lib/VectorTileDataSource.ts

@@ -159,6 +159,16 @@ export interface VectorTileDataSourceParameters extends DataSourceOptions {
      * Default is true (i.e. if not defined it is taken to be true)
      */
     addGroundPlane?: boolean;
+
+    /**
+     * Indicates whether the decoder is allowed to adjust the coordinates to
+     * avoid possible glitches at the 180th meridian.
+     *
+     * @defaultValue `true` if the data service is
+     *               `https://vector.hereapi.com/v2/vectortiles/base/mc`,
+     *               `false` otherwise.
+     */
+    roundUpCoordinatesIfNeeded?: boolean;
 }
 
 /**
@@ -287,6 +297,15 @@ export class VectorTileDataSource extends TileDataSource {
         this.addGroundPlane =
             m_params.addGroundPlane === undefined || m_params.addGroundPlane === true;
 
+        let roundUpCoordinatesIfNeeded = m_params.roundUpCoordinatesIfNeeded;
+
+        if (
+            roundUpCoordinatesIfNeeded === undefined &&
+            (m_params as Partial<OmvWithRestClientParams>)?.baseUrl === hereVectorTileBaseUrl
+        ) {
+            roundUpCoordinatesIfNeeded = true;
+        }
+
         this.m_decoderOptions = {
             showMissingTechniques: this.m_params.showMissingTechniques === true,
             filterDescription: this.m_params.filterDescr,
@@ -297,7 +316,8 @@ export class VectorTileDataSource extends TileDataSource {
             politicalView: this.m_params.politicalView,
             skipShortLabels: this.m_params.skipShortLabels,
             storageLevelOffset: m_params.storageLevelOffset ?? -1,
-            enableElevationOverlay: this.m_params.enableElevationOverlay === true
+            enableElevationOverlay: this.m_params.enableElevationOverlay === true,
+            roundUpCoordinatesIfNeeded
         };
 
         this.maxGeometryHeight = getOptionValue(

@here/harp-vectortile-datasource/lib/VectorTileDecoder.ts

@@ -64,14 +64,20 @@ export class VectorTileDataProcessor implements IGeometryProcessor {
         private readonly m_skipShortLabels = true,
         private readonly m_storageLevelOffset = 0,
         private readonly m_enableElevationOverlay = false,
+        private readonly m_roundUpCoordinatesIfNeeded = false,
         private readonly m_languages?: string[]
     ) {
         const styleSetDataFilter = new StyleSetDataFilter(m_styleSetEvaluator);
         const dataPreFilter = m_dataFilter
             ? new ComposedDataFilter([styleSetDataFilter, m_dataFilter])
             : styleSetDataFilter;
+
         // Register the default adapters.
-        this.m_dataAdapters.push(new OmvDataAdapter(this, dataPreFilter, logger));
+
+        const omvDataAdapter = new OmvDataAdapter(this, dataPreFilter, logger);
+        omvDataAdapter.roundUpCoordinatesIfNeeded = m_roundUpCoordinatesIfNeeded;
+        this.m_dataAdapters.push(omvDataAdapter);
+
         this.m_dataAdapters.push(new GeoJsonVtDataAdapter(this, dataPreFilter, logger));
         this.m_dataAdapters.push(new GeoJsonDataAdapter(this, dataPreFilter, logger));
     }
@@ -301,6 +307,7 @@ export class VectorTileDecoder extends ThemedTileDecoder {
     private m_gatherFeatureAttributes: boolean = false;
     private m_skipShortLabels: boolean = true;
     private m_enableElevationOverlay: boolean = false;
+    private m_roundUpCoordinatesIfNeeded: boolean = false;
 
     /** @override */
     connect(): Promise<void> {
@@ -326,6 +333,7 @@ export class VectorTileDecoder extends ThemedTileDecoder {
             this.m_skipShortLabels,
             this.m_storageLevelOffset,
             this.m_enableElevationOverlay,
+            this.m_roundUpCoordinatesIfNeeded,
             this.languages
         );
 
@@ -420,6 +428,9 @@ export class VectorTileDecoder extends ThemedTileDecoder {
             if (omvOptions.enableElevationOverlay !== undefined) {
                 this.m_enableElevationOverlay = omvOptions.enableElevationOverlay;
             }
+            if (omvOptions.roundUpCoordinatesIfNeeded !== undefined) {
+                this.m_roundUpCoordinatesIfNeeded = omvOptions.roundUpCoordinatesIfNeeded;
+            }
         }
         if (languages !== undefined) {
             this.languages = languages;

@here/harp-vectortile-datasource/lib/adapters/omv/OmvDataAdapter.ts

@@ -177,6 +177,22 @@ function checkWinding(multipolygon: IPolygonGeometry[]) {
     }
 }
 
+function roundUpCoordinates(coordinates: Vector2[], layerExtents: number) {
+    coordinates.forEach(p => {
+        if (p.x === layerExtents - 1) {
+            p.x = layerExtents;
+        }
+    });
+}
+
+function roundUpPolygonCoordinates(geometry: IPolygonGeometry[], layerExtents: number) {
+    geometry.forEach(polygon => polygon.rings.forEach(r => roundUpCoordinates(r, layerExtents)));
+}
+
+function roundUpLineCoordinates(geometry: ILineGeometry[], layerExtents: number) {
+    geometry.forEach(line => roundUpCoordinates(line.positions, layerExtents));
+}
+
 /**
  * The class `OmvDataAdapter` converts OMV protobuf geo data
  * to geometries for the given `IGeometryProcessor`.
@@ -193,6 +209,8 @@ export class OmvDataAdapter implements DataAdapter, OmvVisitor {
     private m_tileKey!: TileKey;
     private m_layer!: com.mapbox.pb.Tile.ILayer;
 
+    public roundUpCoordinatesIfNeeded: boolean = false;
+
     /**
      * Constructs a new [[OmvProtobufDataAdapter]].
      *
@@ -350,6 +368,10 @@ export class OmvDataAdapter implements DataAdapter, OmvVisitor {
             return;
         }
 
+        if (this.mustRoundUpCoordinates) {
+            roundUpLineCoordinates(geometry, layerExtents);
+        }
+
         const env = createFeatureEnv(
             this.m_layer,
             feature,
@@ -410,6 +432,10 @@ export class OmvDataAdapter implements DataAdapter, OmvVisitor {
             return;
         }
 
+        if (this.mustRoundUpCoordinates) {
+            roundUpPolygonCoordinates(geometry, layerExtents);
+        }
+
         checkWinding(geometry);
 
         const env = createFeatureEnv(
@@ -429,4 +455,12 @@ export class OmvDataAdapter implements DataAdapter, OmvVisitor {
             storageLevel
         );
     }
+
+    private get mustRoundUpCoordinates(): boolean {
+        return (
+            this.roundUpCoordinatesIfNeeded &&
+            this.m_tileKey.level < 5 &&
+            this.m_tileKey.column === this.m_tileKey.columnCount() - 1
+        );
+    }
 }