Fix pedestrian area multipolygons (#63)

src/main/java/com/onthegomap/planetiler/basemap/layers/Transportation.java

@@ -513,8 +513,9 @@ public class Transportation implements
   public void process(Tables.OsmHighwayPolygon element, FeatureCollector features) {
     String manMade = element.manMade();
     if (isBridgeOrPier(manMade) ||
-      // ignore underground pedestrian areas
+      // only allow closed ways where area=yes, and multipolygons
-      (element.isArea() && element.layer() >= 0)) {
+      // and ignore underground pedestrian areas
+      (!element.source().canBeLine() && element.layer() >= 0)) {
       String highwayClass = highwayClass(element.highway(), element.publicTransport(), null, element.manMade());
       if (highwayClass != null) {
         features.polygon(LAYER_NAME).setBufferPixels(BUFFER_SIZE)

src/test/java/com/onthegomap/planetiler/basemap/layers/AbstractLayerTest.java

@@ -131,6 +131,17 @@ public abstract class AbstractLayerTest {
     );
   }
 
+  SourceFeature closedWayFeature(Map<String, Object> props) {
+    return SimpleFeature.createFakeOsmFeature(
+      newLineString(0, 0, 1, 0, 1, 1, 0, 1, 0, 0),
+      new HashMap<>(props),
+      OSM_SOURCE,
+      null,
+      0,
+      null
+    );
+  }
+
   SourceFeature polygonFeatureWithArea(double area, Map<String, Object> props) {
     return SimpleFeature.create(
       GeoUtils.worldToLatLonCoords(rectangle(0, Math.sqrt(area))),

src/test/java/com/onthegomap/planetiler/basemap/layers/TransportationTest.java

@@ -990,7 +990,7 @@ public class TransportationTest extends AbstractLayerTest {
 
   @Test
   public void testPedestrianArea() {
-    assertFeatures(10, List.of(Map.of(
+    Map<String, Object> pedestrianArea = Map.of(
       "_layer", "transportation",
       "class", "path",
       "subclass", "pedestrian",
@@ -998,13 +998,36 @@ public class TransportationTest extends AbstractLayerTest {
       "_minzoom", 13,
       "_maxzoom", 14,
       "_type", "polygon"
-    )), process(polygonFeature(Map.of(
+    );
+    Map<String, Object> circularPath = Map.of(
+      "_layer", "transportation",
+      "class", "path",
+      "subclass", "pedestrian",
+
+      "_minzoom", 14,
+      "_maxzoom", 14,
+      "_type", "line"
+    );
+    assertFeatures(14, List.of(pedestrianArea), process(closedWayFeature(Map.of(
       "highway", "pedestrian",
       "area", "yes",
       "foot", "yes"
     ))));
+    assertFeatures(14, List.of(pedestrianArea), process(polygonFeature(Map.of(
+      "highway", "pedestrian",
+      "foot", "yes"
+    ))));
+    assertFeatures(14, List.of(circularPath), process(closedWayFeature(Map.of(
+      "highway", "pedestrian",
+      "foot", "yes"
+    ))));
+    assertFeatures(14, List.of(circularPath), process(closedWayFeature(Map.of(
+      "highway", "pedestrian",
+      "foot", "yes",
+      "area", "no"
+    ))));
     // ignore underground pedestrian areas
-    assertFeatures(10, List.of(),
+    assertFeatures(14, List.of(),
       process(polygonFeature(Map.of(
         "highway", "pedestrian",
         "area", "yes",