Merge pull request #168 from aodn/features/6008-simplify-polygon

Reduce precision default value
aodn · Nov 19, 2024 · 6d820b3 · 6d820b3
2 parents 6197be9 + c5d3ed7
commit 6d820b3
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Showing 2 changed files with 12 additions and 3 deletions.
diff --git a/indexer/src/main/java/au/org/aodn/esindexer/utils/GeometryUtils.java b/indexer/src/main/java/au/org/aodn/esindexer/utils/GeometryUtils.java
@@ -41,10 +41,10 @@ public enum PointOrientation {
     // if we do not preserve this, we will result polygon rejected by elastic due to not having 3 non-collinear
     // points after rounding by the GeometryJson
     protected static GeometryJSON geometryJson = new GeometryJSON(15);
-
+    // A value based on trial and error, this is a default value and user can override it with the yaml file
     @Getter
     @Setter
-    protected static double coastalPrecision = 0.05;
+    protected static double coastalPrecision = 0.1;
 
     // Load a coastline shape file so that we can get a spatial extents that cover sea only
     public static void init() {
@@ -68,7 +68,10 @@ public static void init() {
                     SimpleFeature feature = iterator.next();
                     Geometry landFeatureGeometry = (Geometry) feature.getDefaultGeometry();
 
-                    // This will reduce the points of the shape file for faster processing
+                    // This will reduce the points of the shape file for faster processing, this
+                    // simplification may cause polygon invalid and therefore need to use buffer(0.0) later
+                    // during processing to work around this issue. Another choice is TopologyPreservingSimplifier
+                    // but the polygon output is a bit complicated
                     Geometry simplifiedGeometry = DouglasPeuckerSimplifier
                             .simplify(landFeatureGeometry, getCoastalPrecision()); // Adjust tolerance
 

diff --git a/indexer/src/test/java/au/org/aodn/esindexer/service/StacCollectionMapperServiceTest.java b/indexer/src/test/java/au/org/aodn/esindexer/service/StacCollectionMapperServiceTest.java
@@ -19,6 +19,7 @@
 import lombok.extern.slf4j.Slf4j;
 import org.json.JSONException;
 import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
@@ -78,6 +79,11 @@ public class StacCollectionMapperServiceTest {
 
     protected IndexerServiceImpl indexerService;
 
+    @BeforeAll
+    public static void preSetup() {
+        GeometryUtils.setCoastalPrecision(0.05);
+    }
+
     protected void verify(String expected) throws JsonProcessingException, JSONException {
         Map<?,?> content = objectMapper.readValue(lastRequest.get().document().toString(), Map.class);
         String out = objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(content);