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Add irregular polygon test for centroid
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@utas-raymondng
utas-raymondng committed Sep 23, 2024
1 parent 29046a1 commit 6a4f698
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Showing 7 changed files with 244 additions and 291 deletions.
30 changes: 19 additions & 11 deletions indexer/src/main/java/au/org/aodn/esindexer/utils/GeometryUtils.java
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Original file line number Diff line number Diff line change
Expand Up @@ -344,19 +344,27 @@ protected static Point calculatePolygonCentroid(Geometry geometry) {
}

protected static List<Coordinate> calculateCollectionCentroid(GeometryCollection geometryCollection) {
List<Coordinate> coordinates = new ArrayList<>();
// Loop through each geometry in the collection
for (int i = 0; i < geometryCollection.getNumGeometries(); i++) {
Geometry geometry = geometryCollection.getGeometryN(i);

// Make sure the point will not fall out of the shape, for example a U shape will make
// centroid fall out of the U, so we check if the centroid is out of the shape? if yes then use
// interior point
// Try simplified the polygon to reduce the number of centroid.
Geometry geometry = geometryCollection.union();

if(geometry instanceof GeometryCollection c) {
List<Coordinate> coordinates = new ArrayList<>();
// That means it cannot be simplified, we need centroid of each polygon
for (int i = 0; i < c.getNumGeometries(); i++) {
geometry = geometryCollection.getGeometryN(i);

// Make sure the point will not fall out of the shape, for example a U shape will make
// centroid fall out of the U, so we check if the centroid is out of the shape? if yes then use
// interior point
Point centroid = calculatePolygonCentroid(geometry);
coordinates.add(new Coordinate(centroid.getX(), centroid.getY()));
}
return coordinates;
}
else {
Point centroid = calculatePolygonCentroid(geometry);
coordinates.add(new Coordinate(centroid.getX(), centroid.getY()));
return List.of(new Coordinate(centroid.getX(), centroid.getY()));
}
// Create and return the centroid point
return coordinates;
}
/**
* Create a centroid point for the polygon, this will help to speed up the map processing as there is no need
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1 change: 1 addition & 0 deletions indexer/src/test/java/au/org/aodn/esindexer/service/StacCollectionMapperServiceTests.java
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Expand Up @@ -287,6 +287,7 @@ public void verifyMultipleTemporalExtentsNull() throws IOException, JSONExceptio

Map<?,?> content = objectMapper.readValue(lastRequest.get().document().toString(), Map.class);
String out = objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(content);
log.info(out);
JSONAssert.assertEquals(
objectMapper.readTree(expected).toPrettyString(),
objectMapper.readTree(out.strip()).toPrettyString(),
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51 changes: 50 additions & 1 deletion indexer/src/test/java/au/org/aodn/esindexer/utils/GeometryUtilsTest.java
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Original file line number Diff line number Diff line change
Expand Up @@ -2,19 +2,26 @@

import au.org.aodn.metadata.iso19115_3_2018.MDMetadataType;
import jakarta.xml.bind.JAXBException;
import org.geotools.feature.FeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.geotools.geojson.feature.FeatureJSON;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;
import org.locationtech.jts.geom.*;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.feature.type.FeatureType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

import static au.org.aodn.esindexer.BaseTestClass.readResourceFile;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;

public class GeometryUtilsTest {
protected Logger logger = LoggerFactory.getLogger(GeometryUtilsTest.class);
Expand Down Expand Up @@ -80,4 +87,46 @@ public void verifyLandStrippedFromSpatialExtents() throws IOException, JAXBExcep
assertEquals(126.0, ncoors[3].getX(), 0.01);
assertEquals(-35.9999, ncoors[3].getY(), 0.01);
}
/**
* Given a irregular geojson, with hole the centroid point is still inside the polygon
* @throws IOException
*/
@Test
public void verifyCentroidCorrect() throws IOException {
// You can paste the geojson on geojson.io to see what it looks like
String geojson = readResourceFile("classpath:canned/irregular.geojson");
FeatureJSON json = new FeatureJSON();

// Read the GeoJSON file
StringReader reader = new StringReader(geojson);
FeatureCollection<SimpleFeatureType, SimpleFeature> feature = json.readFeatureCollection(reader);

List<Coordinate> point = GeometryUtils.calculateCollectionCentroid(convertToGeometryCollection(feature));
assertEquals(1, point.size(), "One item");
assertEquals(2.805438932281021, point.get(0).getX(),"X");
assertEquals( 2.0556251797475227, point.get(0).getY(), "Y");
}

protected GeometryCollection convertToGeometryCollection(
FeatureCollection<SimpleFeatureType, SimpleFeature> featureCollection) {
// Create a GeometryFactory
GeometryFactory geometryFactory = new GeometryFactory();

// List to hold the geometries extracted from the FeatureCollection
List<Geometry> geometries = new ArrayList<>();

// Iterate through the FeatureCollection and extract geometries
try(FeatureIterator<SimpleFeature> features = featureCollection.features()) {
while(features.hasNext()) {
Geometry geometry = (Geometry)(features.next()).getDefaultGeometry();
geometries.add(geometry);
}
}

// Convert the list of geometries to an array
Geometry[] geometryArray = geometries.toArray(new Geometry[0]);

// Create and return a GeometryCollection from the array of geometries
return geometryFactory.createGeometryCollection(geometryArray);
}
}
131 changes: 131 additions & 0 deletions indexer/src/test/resources/canned/irregular.geojson
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Original file line number Diff line number Diff line change
@@ -0,0 +1,131 @@
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {},
"geometry": {
"coordinates": [
[
0.2337242356863385,
4.518654452684871
],
[
1.0757323470082554,
4.063032694138045
],
[
2.0156483782505745,
4.772378565429946
],
[
2.6096230924383406,
4.082564826969502
],
[
4.378492845680455,
3.906758793933477
],
[
2.896819657540817,
3.0532809551275335
],
[
1.3237657441414399,
3.3595784740430616
],
[
0.4425944648511688,
2.55781029552125
],
[
1.3498745227876725,
1.8533999697946513
],
[
2.805438932281021,
2.0556251797475227
],
[
3.9933883606575193,
2.042579138064241
],
[
4.469873570940251,
1.2661726935846218
],
[
4.221840173806072,
0.8615572254442299
],
[
4.750542941380246,
0.16317964593562806
],
[
3.647447043602,
0.32635796829360686
],
[
3.3863592571466654,
1.2335444854399356
],
[
2.361589695305099,
0.46342576793742296
],
[
0.5861927474024355,
0.3851015854472166
],
[
-0.7061917955559807,
1.1617610340611009
],
[
-0.7779909368311166,
2.616495167329873
],
[
0.2337242356863385,
4.518654452684871
]
],
"type": "LineString"
}
},
{
"type": "Feature",
"properties": {},
"geometry": {
"coordinates": [
[
1.2323850884183116,
3.8220980913438325
],
[
1.89815894388218,
4.258332255701447
],
[
2.4464432954400195,
3.7895340894263114
],
[
3.379832132021761,
3.724402418269719
],
[
2.59656877265283,
3.424735946359405
],
[
1.2323850884183116,
3.8220980913438325
]
],
"type": "LineString"
}
}
]
}
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