fix polytree (and enable test)

README.md

@@ -6,8 +6,8 @@ A Java port of _[Clipper2](https://github.com/AngusJohnson/Clipper2)_.
 
 ### Port Info
 * _tangiblesoftwaresolutions_' C# to Java Converter did the heavy lifting (but then a lot of manual work was required).
-* Wrapper objects are used to replicate C# `ref` (pass-by-reference) behaviour. This isn't very "Javaific" but avoids an unmanageable refactoring effort.
-* Code passes all polygon and line tests.
+* Wrapper objects are used to replicate C# `ref` (pass-by-reference) behaviour. This isn't very Java-esque but avoids an unmanageable refactoring effort.
+* Code passes all tests: polygon, line and polytree.
 * Uses lower-case (x,y) for point coordinates.
 * Benchmarks can be run by appending `jmh:benchmark` to the chosen maven goal.
 * `scanlineList` from `ClipperBase` uses Java `TreeSet` (variable renamed to `scanlineSet`).

src/main/java/clipper2/Clipper.java

@@ -650,26 +650,20 @@ private static void AddPolyNodeToPaths(PolyPath64 polyPath, Paths64 paths) {
 		if (!polyPath.getPolygon().isEmpty()) {
 			paths.add(polyPath.getPolygon());
 		}
-		for (int i = 0; i < polyPath.getCount(); i++) {
-			AddPolyNodeToPaths((PolyPath64) polyPath.children.get(i), paths);
-		}
+		polyPath.iterator().forEachRemaining(p -> AddPolyNodeToPaths((PolyPath64) p, paths));
 	}
 
 	public static Paths64 PolyTreeToPaths64(PolyTree64 polyTree) {
 		Paths64 result = new Paths64();
-		for (int i = 0; i < polyTree.getCount(); i++) {
-			AddPolyNodeToPaths((PolyPath64) polyTree.children.get(i), result);
-		}
+		polyTree.iterator().forEachRemaining(p -> AddPolyNodeToPaths((PolyPath64) p, result));
 		return result;
 	}
 
 	public static void AddPolyNodeToPathsD(PolyPathD polyPath, PathsD paths) {
 		if (!polyPath.getPolygon().isEmpty()) {
 			paths.add(polyPath.getPolygon());
 		}
-		for (int i = 0; i < polyPath.getCount(); i++) {
-			AddPolyNodeToPathsD((PolyPathD) polyPath.children.get(i), paths);
-		}
+		polyPath.iterator().forEachRemaining(p -> AddPolyNodeToPathsD((PolyPathD) p, paths));
 	}
 
 	public static PathsD PolyTreeToPathsD(PolyTreeD polyTree) {

src/main/java/clipper2/engine/Clipper64.java

@@ -91,7 +91,7 @@ public final boolean Execute(ClipType clipType, FillRule fillRule, PolyTree64 po
 		try {
 			ExecuteInternal(clipType, fillRule);
 			BuildTree(polytree, openPaths);
-		} catch (java.lang.Exception e) {
+		} catch (Exception e) {
 			succeeded = false;
 		}
 

src/main/java/clipper2/engine/ClipperBase.java

@@ -29,7 +29,7 @@
 abstract class ClipperBase {
 
 	private ClipType cliptype;
-	private FillRule fillrule;
+	private FillRule fillrule = FillRule.EvenOdd;
 	private Active actives = null;
 	private Active sel = null;
 	private Joiner horzJoiners = null;
@@ -43,8 +43,8 @@ abstract class ClipperBase {
 	private long currentBotY;
 	private boolean isSortedMinimaList;
 	private boolean hasOpenPaths;
-	public boolean usingPolytree;
-	public boolean succeeded;
+	boolean usingPolytree;
+	boolean succeeded;
 	private boolean preserveCollinear;
 	private boolean reverseSolution;
 
@@ -1230,7 +1230,7 @@ private OutPt AddLocalMaxPoly(Active ae1, Active ae2, Point64 pt) {
 			result = outrec.pts;
 
 			outrec.owner = GetRealOutRec(outrec.owner);
-			if (usingPolytree && outrec.owner.frontEdge == null) {
+			if (usingPolytree && outrec.owner != null && outrec.owner.frontEdge == null) {
 				outrec.owner = GetRealOutRec(outrec.owner.owner);
 			}
 		}

src/main/java/clipper2/engine/PolyPathBase.java

@@ -7,8 +7,8 @@
 
 public abstract class PolyPathBase implements Iterable<PolyPathBase> {
 
-	public PolyPathBase parent;
-	public List<PolyPathBase> children = new ArrayList<>();
+	final PolyPathBase parent;
+	List<PolyPathBase> children = new ArrayList<>();
 
 	PolyPathBase(PolyPathBase parent) {
 		this.parent = parent;
@@ -28,10 +28,6 @@ public final PolyPathIterator iterator() {
 	 * of a polygon.
 	 */
 	public final boolean getIsHole() {
-		return GetIsHole();
-	}
-
-	private boolean GetIsHole() {
 		boolean result = true;
 		PolyPathBase pp = parent;
 		while (pp != null) {

src/main/java/clipper2/engine/PolyPathIterator.java

@@ -4,7 +4,7 @@
 import java.util.List;
 import java.util.NoSuchElementException;
 
-class PolyPathIterator implements Iterator<PolyPathBase> {
+public class PolyPathIterator implements Iterator<PolyPathBase> {
 
 	List<PolyPathBase> ppbList;
 	int position = 0;

src/test/java/clipper2/TestPolytree.java

@@ -6,7 +6,6 @@
 import java.util.List;
 import java.util.stream.Stream;
 
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
@@ -29,7 +28,6 @@ private static final Stream<Arguments> testCases() throws IOException {
 
 	@MethodSource("testCases")
 	@ParameterizedTest(name = "{1} {2} {3}")
-	@Disabled
 	final void RunPolytreeTestCase(TestCase test, String caption, Object o, Object o1) {
 		PolyTree64 solutionTree = new PolyTree64();
 		Paths64 solution_open = new Paths64();
@@ -44,7 +42,7 @@ final void RunPolytreeTestCase(TestCase test, String caption, Object o, Object o
 
 		for (Point64 pt : pointsOfInterestOutside) {
 			for (var path : subject) {
-				assertSame(PointInPolygonResult.IsOutside, Clipper.PointInPolygon(pt, path),
+				assertEquals(PointInPolygonResult.IsOutside, Clipper.PointInPolygon(pt, path),
 						"outside point of interest found inside subject");
 			}
 		}
@@ -59,7 +57,7 @@ final void RunPolytreeTestCase(TestCase test, String caption, Object o, Object o
 					poi_inside_counter++;
 				}
 			}
-			assertSame(1, poi_inside_counter, String.format("poi_inside_counter - expected 1 but got %1$s", poi_inside_counter));
+			assertEquals(1, poi_inside_counter, String.format("poi_inside_counter - expected 1 but got %1$s", poi_inside_counter));
 		}
 
 		clipper.AddSubject(subject);
@@ -71,10 +69,10 @@ final void RunPolytreeTestCase(TestCase test, String caption, Object o, Object o
 		double a1 = Clipper.Area(solutionPaths), a2 = solutionTree.Area();
 
 		assertTrue(a1 > 330000, String.format("solution has wrong area - value expected: 331,052; value returned; %1$s ", a1));
-//
+		
 		assertTrue(Math.abs(a1 - a2) < 0.0001,
 				String.format("solution tree has wrong area - value expected: %1$s; value returned; %2$s ", a1, a2));
-//
+		
 		assertTrue(CheckPolytreeFullyContainsChildren(solutionTree), "The polytree doesn't properly contain its children");
 
 		for (Point64 pt : pointsOfInterestOutside) {
@@ -87,7 +85,7 @@ final void RunPolytreeTestCase(TestCase test, String caption, Object o, Object o
 		}
 	}
 
-	private boolean CheckPolytreeFullyContainsChildren(PolyTree64 polytree) {
+	private static boolean CheckPolytreeFullyContainsChildren(PolyTree64 polytree) {
 		for (var p : polytree) {
 			PolyPath64 child = (PolyPath64) p;
 			if (child.getCount() > 0 && !PolyPathFullyContainsChildren(child)) {
@@ -97,7 +95,7 @@ private boolean CheckPolytreeFullyContainsChildren(PolyTree64 polytree) {
 		return true;
 	}
 
-	private boolean PolyPathFullyContainsChildren(PolyPath64 pp) {
+	private static boolean PolyPathFullyContainsChildren(PolyPath64 pp) {
 		for (var c : pp) {
 			var child = (PolyPath64) c;
 			for (Point64 pt : child.getPolygon()) {
@@ -112,7 +110,7 @@ private boolean PolyPathFullyContainsChildren(PolyPath64 pp) {
 		return true;
 	}
 
-	private boolean PolytreeContainsPoint(PolyTree64 pp, Point64 pt) {
+	private static boolean PolytreeContainsPoint(PolyTree64 pp, Point64 pt) {
 		int counter = 0;
 		for (int i = 0; i < pp.getCount(); i++) {
 			PolyPath64 child = (PolyPath64) pp.get(i);
@@ -124,12 +122,12 @@ private boolean PolytreeContainsPoint(PolyTree64 pp, Point64 pt) {
 		return counter != 0;
 	}
 
-	private void PolyPathContainsPoint(PolyPath64 pp, Point64 pt, RefObject<Integer> counter) {
+	private static void PolyPathContainsPoint(PolyPath64 pp, Point64 pt, RefObject<Integer> counter) {
 		if (Clipper.PointInPolygon(pt, pp.getPolygon()) != PointInPolygonResult.IsOutside) {
 			if (pp.getIsHole()) {
-				--counter.argValue;
+				counter.argValue--;
 			} else {
-				++counter.argValue;
+				counter.argValue++;
 			}
 		}
 		for (int i = 0; i < pp.getCount(); i++) {