align tile buffer for PGIS_TILES (#433)

Author: azahnen

xtraplatform-tiles/src/main/java/de/ii/xtraplatform/tiles/app/FeatureEncoderMVT.java

@@ -12,6 +12,7 @@
 import de.ii.xtraplatform.features.domain.transform.FeatureEncoderSfFlat;
 import de.ii.xtraplatform.features.domain.transform.FeatureSfFlat;
 import de.ii.xtraplatform.tiles.domain.LevelTransformation;
+import de.ii.xtraplatform.tiles.domain.TileBuilder;
 import de.ii.xtraplatform.tiles.domain.TileCoordinates;
 import de.ii.xtraplatform.tiles.domain.TileGenerationContext;
 import de.ii.xtraplatform.tiles.domain.TileGenerationOptions;
@@ -70,7 +71,7 @@ public FeatureEncoderMVT(TileGenerationContext encodingContext) {
     this.geometryFactoryWorld = new GeometryFactory();
 
     final int size = tile.getTileMatrixSet().getTileSize();
-    final int buffer = 8;
+    final int buffer = TileBuilder.BUFFER_SIZE_FORMAL;
     CoordinateXY[] coords = new CoordinateXY[5];
     coords[0] = new CoordinateXY(-buffer, size + buffer);
     coords[1] = new CoordinateXY(size + buffer, size + buffer);

xtraplatform-tiles/src/main/java/de/ii/xtraplatform/tiles/app/TileBuilderPgisAsMvt.java

@@ -290,12 +290,19 @@ private String queryToSql(
             .map(FeatureSchema::getName);
 
     String filter = filtersToSql(providerId, tileset, schema, tms.getId(), level);
+    int buffer = (tms.getTileExtent() / tms.getTileSize()) * TileBuilder.BUFFER_SIZE_FORMAL;
 
     String bounds = "bounds AS (SELECT %1$s AS geom, %2$s::box2d AS b2d)";
     String mvtgeom =
         String.format(
-            "mvtgeom AS (SELECT ST_AsMVTGeom(ST_Transform(A.%1$s, %%3$s), bounds.b2d, %6$d, 8) AS geom, %2$s FROM %3$s A, bounds WHERE (%5$s AND ST_Intersects(A.%1$s, ST_Transform(bounds.geom, %4$s))))",
-            geomColumn, attrColumns, table, nativeCrs.getCode(), filter, tms.getTileExtent());
+            "mvtgeom AS (SELECT ST_AsMVTGeom(ST_Transform(A.%1$s, %%3$s), bounds.b2d, %6$d, %7$d) AS geom, %2$s FROM %3$s A, bounds WHERE (%5$s AND ST_Intersects(A.%1$s, ST_Transform(bounds.geom, %4$s))))",
+            geomColumn,
+            attrColumns,
+            table,
+            nativeCrs.getCode(),
+            filter,
+            tms.getTileExtent(),
+            buffer);
 
     String template =
         String.format(

xtraplatform-tiles/src/main/java/de/ii/xtraplatform/tiles/domain/TileBuilder.java

@@ -19,6 +19,9 @@
 @AutoMultiBind
 public interface TileBuilder {
 
+  // buffer in relation to the "formal" tile size (256 for WMQ)
+  int BUFFER_SIZE_FORMAL = 8;
+
   int getPriority();
 
   boolean isApplicable(String featureProviderId);