From 16585efe71bec66047d55dbe0e837b6d15d64c44 Mon Sep 17 00:00:00 2001
From: AlexRyanUSACE <alex.ryan@usace.army.mil>
Date: Tue, 1 Sep 2026 13:31:40 -0400
Subject: [PATCH] Fixed issue with inconsistent upward propagation of RTreeNode
 MBR size increases

---
 Nsi.Geospatial/Spatial/RTreeNode.cs      | 30 ++++++++++++++----------
 tests/Nsi.Geospatial.Tests/RTreeTests.cs |  8 +++++--
 2 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/Nsi.Geospatial/Spatial/RTreeNode.cs b/Nsi.Geospatial/Spatial/RTreeNode.cs
index af1df4e..474634f 100644
--- a/Nsi.Geospatial/Spatial/RTreeNode.cs
+++ b/Nsi.Geospatial/Spatial/RTreeNode.cs
@@ -56,18 +56,18 @@ public void split()
             {
                 _parent._children.Remove(this);
                 newKidsOntheBlock[0].UpdateParents(_parent);
-                newKidsOntheBlock[1].UpdateParents(_parent);
-                _parent.addChild(newKidsOntheBlock[0], true);
-                _parent.addChild(newKidsOntheBlock[1], false);                
+                newKidsOntheBlock[1].UpdateParents(_parent);                
+                _parent.addChild(newKidsOntheBlock[0], false, true);
+                _parent.addChild(newKidsOntheBlock[1], true, true);                
             }
             else
             {
                 RTreeNode newRoot = new RTreeNode(_treeManager, maxChidrens, minChidrens);
                 newKidsOntheBlock[0].UpdateParents(newRoot);
                 newKidsOntheBlock[1].UpdateParents(newRoot);
-                newRoot.addChild(newKidsOntheBlock[0], true);
-                newRoot.addChild(newKidsOntheBlock[1], false);        
-                _treeManager._root = newRoot;
+                newRoot.addChild(newKidsOntheBlock[0], false, true);
+                newRoot.addChild(newKidsOntheBlock[1], true, true);        
+                _treeManager._root = newRoot;                
             }    
         }
         private void buildChildOptions(List<(RTreeNode[], double[])> options, bool xAxis, bool min)
@@ -93,11 +93,11 @@ private void buildChildOptions(List<(RTreeNode[], double[])> options, bool xAxis
                     var Child = sortedChidrens[i];
                     if (i < split)
                     {
-                        node1.addChild(Child, true);
+                        node1.addChild(Child, false, false);
                     }
                     else
                     {
-                        node2.addChild(Child, true);
+                        node2.addChild(Child, false, false);
                     }                   
                 }
                 double overlapWidth = Math.Max(0, Math.Min(node1.MBRXMax, node2.MBRXMax) - Math.Max(node1.MBRXMin, node2.MBRXMin));
@@ -118,7 +118,7 @@ public void addFeatureChild(RTreeNode feature)
         {
             if(getIsEndNode) 
             { 
-                addChild(feature, false); 
+                addChild(feature, true, true); 
             }            
             else
             {
@@ -157,9 +157,9 @@ public void addFeatureChildEnforceIntersect(RTreeNode feature)
                     minExtension = extensionReq;
                 }
             }
-            bestCandidate.addChild(feature, false);
+            bestCandidate.addChild(feature, true, true);
         }
-        public void addChild(RTreeNode child, bool evaluation) 
+        public void addChild(RTreeNode child, bool canSplit, bool canPropagateMBRup) 
         {
             _children.Add(child);
             child._parent = this;
@@ -167,10 +167,14 @@ public void addChild(RTreeNode child, bool evaluation)
             if(child.MBRXMax > MBRXMax) { MBRXMax = child.MBRXMax; }
             if(child.MBRYMin < MBRYMin) { MBRYMin = child.MBRYMin; }
             if(child.MBRYMax > MBRYMax) { MBRYMax = child.MBRYMax; }
-            if(_children.Count > maxChidrens && !evaluation)
+            if(_children.Count > maxChidrens && canSplit)
             {
                 split();
             }
+            else if(canPropagateMBRup)
+            {
+                RecomputeMBR();
+            }
         }
         public void RecomputeMBR()
         {
@@ -318,4 +322,4 @@ public double getPerimeter
             get { return 2 * ((MBRXMax - MBRXMin) + (MBRYMax - MBRYMin)); }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/tests/Nsi.Geospatial.Tests/RTreeTests.cs b/tests/Nsi.Geospatial.Tests/RTreeTests.cs
index 45b0ecd..755e0be 100644
--- a/tests/Nsi.Geospatial.Tests/RTreeTests.cs
+++ b/tests/Nsi.Geospatial.Tests/RTreeTests.cs
@@ -55,7 +55,7 @@ public void FindByInd_ReturnsLeafToRootPath()
         Assert.NotNull(featureIndex);
     }
 
-    [Fact(Skip = "Fails by design: asserts correct behavior that the original (unfixed) RTree split/overlap defects violate. Re-enable once the RTree defects are fixed.")]
+    [Fact] //(Skip = "Fails by design: asserts correct behavior that the original (unfixed) RTree split/overlap defects violate. Re-enable once the RTree defects are fixed.")]
     public void BulkInsert_AllFeaturesFindableByPoint()
     {
         var tree = new RTreeManager(minChilds: 3, maxChilds: 6);
@@ -65,6 +65,10 @@ public void BulkInsert_AllFeaturesFindableByPoint()
         for (int i = 0; i < 500; i++)
         {
             var hits = FeatureIndicesAt(tree, i * 10 + 2.5, i * 10 + 2.5);
+            if (!hits.Contains(i))
+            {
+        string test = "WTF";
+            }
             Assert.Contains(i, hits);
         }
     }
@@ -107,4 +111,4 @@ private static List<int> FeatureIndicesAt(RTreeManager tree, double x, double y)
         }
         return indices;
     }
-}
\ No newline at end of file
+}