# UNDF: UNDF-2026-000000956
--- a/source/simulation2/components/CCmpObstructionManager.cpp
+++ b/source/simulation2/components/CCmpObstructionManager.cpp
@@ -1,6 +1,7 @@
 // CWE-407: CCmpObstructionManager dirty shape tracking uses std::vector with
 // std::find for dedup, causing O(N*D) per-frame cost where N = nearby shapes
 // and D = dirty list size. In large battles (200v200), hundreds of shapes
 // move per frame, making this O(N^2). Fix: use std::unordered_set for O(1) lookup.
+#include <unordered_set>

 // --- Declaration change ---
@@ -525,8 +526,8 @@
 	// Dynamic updates for the long-range pathfinder
 	GridUpdateInformation m_UpdateInformations;
 	// These vectors might contain shapes that were deleted
-	std::vector<u32> m_DirtyStaticShapes;
-	std::vector<u32> m_DirtyUnitShapes;
+	std::unordered_set<u32> m_DirtyStaticShapes;
+	std::unordered_set<u32> m_DirtyUnitShapes;

 // --- MakeDirtyStatic ---
@@ -584,8 +585,7 @@
-			if (std::find(m_DirtyStaticShapes.begin(), m_DirtyStaticShapes.end(), index) == m_DirtyStaticShapes.end())
-				m_DirtyStaticShapes.push_back(index);
+			m_DirtyStaticShapes.insert(index);

 			// All shapes overlapping the updated part of the grid should be dirtied too.
@@ -599,12 +599,10 @@
 			std::vector<u32> staticsNear;
 			m_StaticSubdivision.GetInRange(staticsNear, center - hbox - expand*2, center + hbox + expand*2);
 			for (u32& staticId : staticsNear)
-				if (std::find(m_DirtyStaticShapes.begin(), m_DirtyStaticShapes.end(), staticId) == m_DirtyStaticShapes.end())
-					m_DirtyStaticShapes.push_back(staticId);
+				m_DirtyStaticShapes.insert(staticId);

 			std::vector<u32> unitsNear;
 			m_UnitSubdivision.GetInRange(unitsNear, center - hbox - expand*2, center + hbox + expand*2);
 			for (u32& unitId : unitsNear)
-				if (std::find(m_DirtyUnitShapes.begin(), m_DirtyUnitShapes.end(), unitId) == m_DirtyUnitShapes.end())
-					m_DirtyUnitShapes.push_back(unitId);
+				m_DirtyUnitShapes.insert(unitId);

 // --- MakeDirtyUnit ---
@@ -624,8 +622,7 @@
-			if (std::find(m_DirtyUnitShapes.begin(), m_DirtyUnitShapes.end(), index) == m_DirtyUnitShapes.end())
-				m_DirtyUnitShapes.push_back(index);
+			m_DirtyUnitShapes.insert(index);

@@ -637,12 +634,10 @@
 			std::vector<u32> staticsNear;
 			m_StaticSubdivision.GetNear(staticsNear, center, shape.clearance + m_MaxClearance*2);
 			for (u32& staticId : staticsNear)
-				if (std::find(m_DirtyStaticShapes.begin(), m_DirtyStaticShapes.end(), staticId) == m_DirtyStaticShapes.end())
-					m_DirtyStaticShapes.push_back(staticId);
+				m_DirtyStaticShapes.insert(staticId);

 			std::vector<u32> unitsNear;
 			m_UnitSubdivision.GetNear(unitsNear, center, shape.clearance + m_MaxClearance*2);
 			for (u32& unitId : unitsNear)
-				if (std::find(m_DirtyUnitShapes.begin(), m_DirtyUnitShapes.end(), unitId) == m_DirtyUnitShapes.end())
-					m_DirtyUnitShapes.push_back(unitId);
+				m_DirtyUnitShapes.insert(unitId);

 // --- RasterizeHelper ---
@@ -1116,7 +1111,7 @@
-		if (!fullUpdate && std::find(m_DirtyStaticShapes.begin(), m_DirtyStaticShapes.end(), pair.first) == m_DirtyStaticShapes.end())
+		if (!fullUpdate && m_DirtyStaticShapes.find(pair.first) == m_DirtyStaticShapes.end())
 			continue;

@@ -1139,7 +1134,7 @@
-		if (!fullUpdate && std::find(m_DirtyUnitShapes.begin(), m_DirtyUnitShapes.end(), pair.first) == m_DirtyUnitShapes.end())
+		if (!fullUpdate && m_DirtyUnitShapes.find(pair.first) == m_DirtyUnitShapes.end())
 			continue;