diff --git a/src/common/rendering/hwrenderer/data/hw_renderstate.h b/src/common/rendering/hwrenderer/data/hw_renderstate.h
index 90c53ff8a1..97ffba4b06 100644
--- a/src/common/rendering/hwrenderer/data/hw_renderstate.h
+++ b/src/common/rendering/hwrenderer/data/hw_renderstate.h
@@ -735,7 +735,7 @@ public:
 
 	inline void PushVisibleSurface(int surfaceIndex, LevelMeshSurface* surface)
 	{
-		if(surface->needsUpdate && mActiveLightmapSurfaces.Size() < lm_max_updates && mActiveLightmapSurfaces.Find(surfaceIndex) >= mActiveLightmapSurfaces.Size()) // yikes, how awful
+		if(surface->needsUpdate && mActiveLightmapSurfaces.Size() < unsigned(lm_max_updates) && mActiveLightmapSurfaces.Find(surfaceIndex) >= mActiveLightmapSurfaces.Size()) // yikes, how awful
 			mActiveLightmapSurfaces.Push(surfaceIndex);
 	}
 
diff --git a/src/rendering/hwrenderer/doom_levelmesh.cpp b/src/rendering/hwrenderer/doom_levelmesh.cpp
index cd9dd011c2..41727a2fff 100644
--- a/src/rendering/hwrenderer/doom_levelmesh.cpp
+++ b/src/rendering/hwrenderer/doom_levelmesh.cpp
@@ -98,6 +98,15 @@ DoomLevelMesh::DoomLevelMesh(FLevelLocals &doomMap)
 	BindLightmapSurfacesToGeometry(doomMap);
 
 	Collision = std::make_unique<TriangleMeshShape>(MeshVertices.Data(), MeshVertices.Size(), MeshElements.Data(), MeshElements.Size());
+
+	// Runtime stuff
+	for (auto& surface : Surfaces)
+	{
+		if ((surface.Type == ST_FLOOR || surface.Type == ST_CEILING) && surface.ControlSector)
+		{
+			XFloorToSurface[surface.ControlSector].Push(&surface);
+		}
+	}
 }
 
 void DoomLevelMesh::CreatePortals()
diff --git a/src/rendering/hwrenderer/doom_levelmesh.h b/src/rendering/hwrenderer/doom_levelmesh.h
index 1de70b7c5e..d1e8216084 100644
--- a/src/rendering/hwrenderer/doom_levelmesh.h
+++ b/src/rendering/hwrenderer/doom_levelmesh.h
@@ -27,6 +27,9 @@ class DoomLevelMesh : public LevelMesh
 {
 public:
 	DoomLevelMesh(FLevelLocals &doomMap);
+	
+	void CreatePortals();
+	void DumpMesh(const FString& objFilename, const FString& mtlFilename) const;
 
 	bool TraceSky(const FVector3& start, FVector3 direction, float dist)
 	{
@@ -40,17 +43,15 @@ public:
 	LevelMeshSurface* GetSurface(int index) override { return &Surfaces[index]; }
 	int GetSurfaceCount() override { return Surfaces.Size(); }
 
+
 	TArray<DoomLevelMeshSurface> Surfaces;
 	std::vector<std::unique_ptr<LevelMeshLight>> Lights;
 	TArray<FVector2> LightmapUvs;
-
 	static_assert(alignof(FVector2) == alignof(float[2]) && sizeof(FVector2) == sizeof(float) * 2);
 
-	void DumpMesh(const FString& objFilename, const FString& mtlFilename) const;
+	// runtime utility variables
+	TMap<sector_t*, TArray<DoomLevelMeshSurface*>> XFloorToSurface;
 
-	void SetupLightmapUvs();
-
-	void CreatePortals();
 private:
 	void CreateSubsectorSurfaces(FLevelLocals &doomMap);
 	void CreateCeilingSurface(FLevelLocals &doomMap, subsector_t *sub, sector_t *sector, int typeIndex, bool is3DFloor);
@@ -61,6 +62,7 @@ private:
 	void SetSubsectorLightmap(DoomLevelMeshSurface* surface);
 	void SetSideLightmap(DoomLevelMeshSurface* surface);
 
+	void SetupLightmapUvs();
 	void PropagateLight(const LevelMeshLight* light, std::set<LevelMeshPortal, RecursivePortalComparator>& touchedPortals, int lightPropagationRecursiveDepth);
 	void CreateLightList();
 
diff --git a/src/rendering/hwrenderer/scene/hw_flats.cpp b/src/rendering/hwrenderer/scene/hw_flats.cpp
index c2c36f46a4..46ff650e3e 100644
--- a/src/rendering/hwrenderer/scene/hw_flats.cpp
+++ b/src/rendering/hwrenderer/scene/hw_flats.cpp
@@ -192,12 +192,24 @@ void HWFlat::DrawSubsectors(HWDrawInfo *di, FRenderState &state)
 	}
 	state.SetLightIndex(dynlightindex);
 
+	const auto* lm = &sector->Level->levelMesh->Surfaces[0]; // temporay hack on top of a temporary hack
+
 	for (auto& subsector : section->subsectors)
 	{
-		auto lightmap = subsector->lightmap[ceiling ? 1 : 0][0];
-		if (lightmap)
+		if (auto lightmap = subsector->lightmap[ceiling ? 1 : 0][0])
 		{
-			state.PushVisibleSurface(lightmap - &subsector->sector->Level->levelMesh->Surfaces[0], lightmap);
+			state.PushVisibleSurface(lightmap - lm, lightmap);
+		}
+	}
+
+	if (auto subsectors = sector->Level->levelMesh->XFloorToSurface.CheckKey(sector))
+	{
+		for (auto* surface : *subsectors)
+		{
+			if (surface)
+			{
+				state.PushVisibleSurface(surface - lm, surface);
+			}
 		}
 	}