diff --git a/src/actor.h b/src/actor.h
index 043da9b7ca..d87c51e98a 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -1083,6 +1083,7 @@ public:
 	FBlockNode		*BlockNode;			// links in blocks (if needed)
 	struct sector_t	*Sector;
 	subsector_t *		subsector;
+	FSection *			section;
 	double			floorz, ceilingz;	// closest together of contacted secs
 	double			dropoffz;		// killough 11/98: the lowest floor over all contacted Sectors.
 
diff --git a/src/g_levellocals.h b/src/g_levellocals.h
index dfdb6dbef6..6a42c12c5d 100644
--- a/src/g_levellocals.h
+++ b/src/g_levellocals.h
@@ -42,6 +42,7 @@
 #include "p_blockmap.h"
 #include "p_local.h"
 #include "p_destructible.h"
+#include "hwrenderer/data/hw_sections.h"
 
 struct FLevelLocals
 {
@@ -94,6 +95,8 @@ struct FLevelLocals
 	TArray<FLinePortal*> linkedPortals;	// only the linked portals, this is used to speed up looking for them in P_CollectConnectedGroups.
 	TArray<FSectorPortalGroup *> portalGroups;	
 	TArray<FLinePortalSpan> linePortalSpans;
+	FSectionContainer sections;
+
 	int NumMapSections;
 
 	TArray<zone_t>	Zones;
diff --git a/src/hwrenderer/data/hw_sections.cpp b/src/hwrenderer/data/hw_sections.cpp
index 9364b9712b..e56736191a 100644
--- a/src/hwrenderer/data/hw_sections.cpp
+++ b/src/hwrenderer/data/hw_sections.cpp
@@ -88,6 +88,7 @@ struct Group
 	TArray<GroupWork> groupedSections;
 	TMap<int, bool> sideMap;
 	TArray<WorkSectionLine*> segments;
+	TArray<int> subsectors;
 };
 
 class FSectionCreator
@@ -531,12 +532,14 @@ public:
 	{
 		const double MAX_GROUP_DIST = 256;
 		TArray<GroupWork> build;
+		TArray<int> subsectorcopy;
 
 		if (workingSet.Size() == 1)
 		{
 			groupForSection[workingSet[0].index] = groups.Size();
 			Group g;
 			g.groupedSections = std::move(workingSet);
+			g.subsectors = std::move(rawsections[workingSet[0].index]);
 			groups.Push(std::move(g));
 			return;
 		}
@@ -546,8 +549,10 @@ public:
 			build.Clear();
 			build.Push(workingSet[0]);
 			groupForSection[workingSet[0].index] = groups.Size();
+			subsectorcopy = std::move(rawsections[workingSet[0].index]);
 			workingSet.Delete(0);
 
+
 			// Don't use iterators here. These arrays are modified inside.
 			for (unsigned j = 0; j < build.Size(); j++)
 			{
@@ -560,6 +565,7 @@ public:
 					{
 						build.Push(workingSet[i]);
 						groupForSection[workingSet[i].index] = groups.Size();
+						subsectorcopy.Append(rawsections[workingSet[i].index]);
 						workingSet.Delete(i);
 						i--;
 						continue;
@@ -570,6 +576,7 @@ public:
 					{
 						build.Push(workingSet[i]);
 						groupForSection[workingSet[i].index] = groups.Size();
+						subsectorcopy.Append(rawsections[workingSet[i].index]);
 						workingSet.Delete(i);
 						i--;
 						continue;
@@ -578,6 +585,7 @@ public:
 			}
 			Group g;
 			g.groupedSections = std::move(build);
+			g.subsectors = std::move(subsectorcopy);
 			groups.Push(std::move(g));
 		}
 	}
@@ -615,6 +623,7 @@ public:
 		output.allIndices.Resize(level.subsectors.Size() + level.sides.Size());
 		output.sectionForSubsectorPtr = &output.allIndices[0];
 		output.sectionForSidedefPtr = &output.allIndices[level.subsectors.Size()];
+		memset(output.sectionForSubsectorPtr, -1, sizeof(int) * level.subsectors.Size());
 
 		unsigned numsegments = 0;
 		unsigned numsides = 0;
@@ -642,9 +651,11 @@ public:
 		}
 		output.allLines.Resize(numsegments);
 		output.allSides.Resize(numsides);
+		output.allSubsectors.Resize(level.subsectors.Size());
 
 		numsegments = 0;
 		numsides = 0;
+		unsigned numsubsectors = 0;
 
 		// Now piece it all together
 		unsigned curgroup = 0;
@@ -658,6 +669,7 @@ public:
 			dest.validcount = 0;
 			dest.segments.Set(&output.allLines[numsegments], group.segments.Size());
 			dest.sides.Set(&output.allSides[numsides], group.sideMap.CountUsed());
+			dest.subsectors.Set(&output.allSubsectors[numsubsectors]);
 			dest.bounds = {1e32, 1e32, -1e32, -1e32};
 			numsegments += group.segments.Size();
 
@@ -677,7 +689,14 @@ public:
 			while (it.NextPair(pair))
 			{
 				output.allSides[numsides++] = &level.sides[pair->Key];
+				output.sectionForSidedefPtr[pair->Key] = curgroup;
 			}
+			memcpy(&output.allSubsectors[numsubsectors], &group.subsectors[0], group.subsectors.Size() * sizeof(subsector_t*));
+			for (auto ssi : group.subsectors)
+			{
+				output.sectionForSubsectorPtr[ssi] = curgroup;
+			}
+			numsubsectors += group.subsectors.Size();
 			curgroup++;
 		}
 	}
@@ -739,12 +758,8 @@ void PrintSections(FSectionContainer &container)
 //
 //=============================================================================
 
-void MakeSections()
+void CreateSections(FSectionContainer &container)
 {
-	FSectionContainer container;
-	cycle_t timer;
-	timer.Reset();
-	timer.Clock();
 	FSectionCreator creat;
 	creat.GroupSubsectors();
 	creat.CompileSections();
@@ -753,12 +768,9 @@ void MakeSections()
 	creat.FindOuterLoops();
 	creat.GroupSections();
 	creat.ConstructOutput(container);
-	timer.Unclock();
-	PrintSections(container);
-	Printf("Time = %2.3f ms\n", timer.TimeMS());
 }
 
-CCMD(makesections)
+CCMD(printsections)
 {
-	MakeSections();
+	PrintSections(level.sections);
 }
\ No newline at end of file
diff --git a/src/hwrenderer/data/hw_sections.h b/src/hwrenderer/data/hw_sections.h
index 1cc6f2efa2..6edda1143d 100644
--- a/src/hwrenderer/data/hw_sections.h
+++ b/src/hwrenderer/data/hw_sections.h
@@ -2,9 +2,19 @@
 #ifndef __GL_SECTIONS_H
 #define __GL_SECTIONS_H
 
+#include <algorithm>
 #include "tarray.h"
 #include "r_defs.h"
 
+// Undefine Windows garbage.
+#ifdef min
+#undef min
+#endif
+
+#ifdef max
+#undef max
+#endif
+
 //==========================================================================
 //
 //
@@ -71,6 +81,7 @@ struct FSection
 	// tbd: Do we need a list of subsectors here? Ideally the subsectors should not be used anywhere anymore except for finding out where a location is.
 	TArrayView<FSectionLine> segments;
 	TArrayView<side_t *>	 sides;		// contains all sidedefs, including the internal ones that do not make up the outer shape. (this list is not exclusive. A sidedef can be in multiple sections!)
+	TArrayView<subsector_t *>	 subsectors;		// contains all sidedefs, including the internal ones that do not make up the outer shape. (this list is not exclusive. A sidedef can be in multiple sections!)
 	sector_t				*sector;
 	FLightNode				*lighthead;	// Light nodes (blended and additive)
 	BoundingRect			 bounds;
@@ -86,6 +97,7 @@ public:
 	TArray<FSection> allSections;
 	//TArray<vertex_t*> allVertices;
 	TArray<side_t *> allSides;
+	TArray<subsector_t *> allSubsectors;
 	TArray<int> allIndices;
 
 	int *sectionForSubsectorPtr;			// stored inside allIndices
@@ -123,4 +135,6 @@ public:
 };
 
 
+void CreateSections(FSectionContainer &container);
+
 #endif
\ No newline at end of file
diff --git a/src/p_maputl.cpp b/src/p_maputl.cpp
index c94d80073f..19c9496d33 100644
--- a/src/p_maputl.cpp
+++ b/src/p_maputl.cpp
@@ -470,6 +470,7 @@ void AActor::LinkToWorld(FLinkContext *ctx, bool spawningmapthing, sector_t *sec
 
 	Sector = sector;
 	subsector = R_PointInSubsector(Pos());	// this is from the rendering nodes, not the gameplay nodes!
+	section = level.sections.SectionForSubsector(subsector->Index());
 
 	if (!(flags & MF_NOSECTOR))
 	{
diff --git a/src/p_setup.cpp b/src/p_setup.cpp
index d3ff4c4999..a204144efb 100644
--- a/src/p_setup.cpp
+++ b/src/p_setup.cpp
@@ -3559,6 +3559,7 @@ void P_FreeLevelData ()
 
 
 	FBehavior::StaticUnloadModules ();
+	level.sections.Clear();
 	level.segs.Clear();
 	level.sectors.Clear();
 	level.lines.Clear();
diff --git a/src/r_data/renderinfo.cpp b/src/r_data/renderinfo.cpp
index bf59ec0c0a..f50c32d518 100644
--- a/src/r_data/renderinfo.cpp
+++ b/src/r_data/renderinfo.cpp
@@ -532,6 +532,8 @@ static void PrepareSegs()
 
 void InitRenderInfo()
 {
+	CreateSections(level.sections);
+
 	PrepareSegs();
 	PrepareSectorData();
 	InitVertexData();