From 70da00716915401f2eac3475cf1020728c7a9f1e Mon Sep 17 00:00:00 2001
From: Rowan Winsemius <rowanwins@yahoo.com.au>
Date: Mon, 4 Apr 2022 22:33:15 +1000
Subject: [PATCH 1/3] Remove unnecessary holes from output

---
 src/connect_edges.js | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/connect_edges.js b/src/connect_edges.js
index 0ce5c43..8e232b8 100644
--- a/src/connect_edges.js
+++ b/src/connect_edges.js
@@ -96,7 +96,13 @@ function initializeContourFromContext(event, contours, contourId) {
     // in an earlier iteration, otherwise it wouldn't be possible that it is "previous in
     // result".
     const lowerContourId = prevInResult.outputContourId;
-    const lowerResultTransition = prevInResult.resultTransition;
+    let lowerResultTransition = prevInResult.resultTransition;
+    if (!event.isExteriorRing && !event.isSubject) {
+      contour.cull = true;
+    } else if (!event.isExteriorRing && prevInResult.isExteriorRing) {
+      lowerResultTransition = 1;
+    }
+
     if (lowerResultTransition > 0) {
       // We are inside. Now we have to check if the thing below us is another hole or
       // an exterior contour.
@@ -182,5 +188,5 @@ export default function connectEdges(sortedEvents) {
     contours.push(contour);
   }
 
-  return contours;
+  return contours.filter(c => c.cull !== true);
 }

From 6a940e80b146a5f2d0910a236352bc1aa27f6a07 Mon Sep 17 00:00:00 2001
From: Rowan Winsemius <rowanwins@yahoo.com.au>
Date: Mon, 4 Apr 2022 22:34:03 +1000
Subject: [PATCH 2/3] add test fixture

---
 test/fixtures/issue69.geojson | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 test/fixtures/issue69.geojson

diff --git a/test/fixtures/issue69.geojson b/test/fixtures/issue69.geojson
new file mode 100644
index 0000000..98db265
--- /dev/null
+++ b/test/fixtures/issue69.geojson
@@ -0,0 +1,21 @@
+{
+  "type": "FeatureCollection",
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Polygon",
+        "coordinates": [[[2, 0],[10, 10],[10, 0],[2, 0]]]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Polygon",
+        "coordinates": [[[5, 1],[12, 1],[12, 9],[5, 9],[5, 1]],[[6, 2],[11, 8],[6, 8],[6, 2]]]
+      }
+    }
+  ]
+}
\ No newline at end of file

From 5bacc2775d00860cea449d1ffeec6999e34223b6 Mon Sep 17 00:00:00 2001
From: Rowan Winsemius <rowanwins@yahoo.com.au>
Date: Mon, 4 Apr 2022 22:44:49 +1000
Subject: [PATCH 3/3] adjust approach to retain indexes

---
 src/connect_edges.js | 2 +-
 src/index.js         | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/connect_edges.js b/src/connect_edges.js
index 8e232b8..48daeb9 100644
--- a/src/connect_edges.js
+++ b/src/connect_edges.js
@@ -188,5 +188,5 @@ export default function connectEdges(sortedEvents) {
     contours.push(contour);
   }
 
-  return contours.filter(c => c.cull !== true);
+  return contours;
 }
diff --git a/src/index.js b/src/index.js
index b3a3f69..c92e5b1 100644
--- a/src/index.js
+++ b/src/index.js
@@ -80,7 +80,7 @@ export default function boolean(subject, clipping, operation) {
   const polygons = [];
   for (let i = 0; i < contours.length; i++) {
     let contour = contours[i];
-    if (contour.isExterior()) {
+    if (contour.isExterior() && contour.cull !== true) {
       // The exterior ring goes first
       let rings = [contour.points];
       // Followed by holes if any