diff --git a/src/common/rendering/hwrenderer/data/hw_levelmesh.h b/src/common/rendering/hwrenderer/data/hw_levelmesh.h
index bd9b7555c8..c4d298a010 100644
--- a/src/common/rendering/hwrenderer/data/hw_levelmesh.h
+++ b/src/common/rendering/hwrenderer/data/hw_levelmesh.h
@@ -52,6 +52,8 @@ struct LevelMeshSurface
 	int texWidth = 0;
 	int texHeight = 0;
 
+	bool needsUpdate = true;
+
 	//
 	// Required for internal lightmapper:
 	//
diff --git a/src/common/rendering/hwrenderer/data/hw_renderstate.h b/src/common/rendering/hwrenderer/data/hw_renderstate.h
index 7ac3662a25..e305c2ae06 100644
--- a/src/common/rendering/hwrenderer/data/hw_renderstate.h
+++ b/src/common/rendering/hwrenderer/data/hw_renderstate.h
@@ -3,6 +3,7 @@
 #include "vectors.h"
 #include "matrix.h"
 #include "hw_material.h"
+#include "hw_levelmesh.h"
 #include "texmanip.h"
 #include "version.h"
 #include "i_interface.h"
@@ -257,6 +258,7 @@ protected:
 
 	EPassType mPassType = NORMAL_PASS;
 
+	TArray<LevelMeshSurface*> mActiveLightmapSurfaces;
 public:
 
 	uint64_t firstFrame = 0;
@@ -729,6 +731,22 @@ public:
 		return SetViewpoint(matrices);
 	}
 
+	inline void PushVisibleSurface(LevelMeshSurface* surface)
+	{
+		if(surface && surface->needsUpdate && mActiveLightmapSurfaces.Find(surface) >= mActiveLightmapSurfaces.Size()) // yikes, how awful
+			mActiveLightmapSurfaces.Push(surface);
+	}
+
+	inline const auto& GetVisibleSurfaceList() const
+	{
+		return mActiveLightmapSurfaces;
+	}
+
+	inline void ClearVisibleSurfaceList()
+	{
+		mActiveLightmapSurfaces.Clear();
+	}
+
 	// API-dependent render interface
 
 	// Worker threads
diff --git a/src/common/rendering/v_video.h b/src/common/rendering/v_video.h
index 93e763bcf0..e0452890bc 100644
--- a/src/common/rendering/v_video.h
+++ b/src/common/rendering/v_video.h
@@ -156,6 +156,7 @@ public:
 	virtual bool IsPoly() { return false; }
 	virtual bool CompileNextShader() { return true; }
 	virtual void SetLevelMesh(LevelMesh *mesh) { }
+	virtual void UpdateLightmaps(const TArray<LevelMeshSurface*>& surfaces) {}
 	bool allowSSBO() const
 	{
 #ifndef HW_BLOCK_SSBO
diff --git a/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp b/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp
index 86790ae845..4c43be42fd 100644
--- a/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp
+++ b/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp
@@ -31,6 +31,17 @@ VkLightmap::~VkLightmap()
 		lights.Buffer->Unmap();
 }
 
+static int lastSurfaceCount;
+
+ADD_STAT(lightmapper)
+{
+	FString out;
+	
+	out.Format("Last batch surface count: %d", lastSurfaceCount);
+
+	return out;
+}
+
 void VkLightmap::Raytrace(LevelMesh* level, const TArray<LevelMeshSurface*>& surfaces)
 {
 	bool newLevel = (mesh != level);
@@ -42,8 +53,15 @@ void VkLightmap::Raytrace(LevelMesh* level, const TArray<LevelMeshSurface*>& sur
 		CreateAtlasImages();
 	}
 
+	for (auto surface : surfaces)
+	{
+		surface->needsUpdate = false;
+	}
+
 	UploadUniforms();
 
+	lastSurfaceCount = surfaces.Size();
+
 	for (size_t pageIndex = 0; pageIndex < atlasImages.size(); pageIndex++)
 	{
 		RenderAtlasImage(pageIndex, surfaces);
@@ -53,7 +71,7 @@ void VkLightmap::Raytrace(LevelMesh* level, const TArray<LevelMeshSurface*>& sur
 	{
 		ResolveAtlasImage(pageIndex);
 		BlurAtlasImage(pageIndex);
-		CopyAtlasImageResult(pageIndex);
+		CopyAtlasImageResult(pageIndex, surfaces);
 	}
 }
 
@@ -375,14 +393,14 @@ void VkLightmap::BlurAtlasImage(size_t pageIndex)
 	}
 }
 
-void VkLightmap::CopyAtlasImageResult(size_t pageIndex)
+void VkLightmap::CopyAtlasImageResult(size_t pageIndex, const TArray<LevelMeshSurface*>& surfaces)
 {
 	LightmapImage& img = atlasImages[pageIndex];
 
 	std::vector<VkImageCopy> regions;
-	for (int i = 0, count = mesh->GetSurfaceCount(); i < count; i++)
+	for (int i = 0, count = surfaces.Size(); i < count; i++)
 	{
-		LevelMeshSurface* surface = mesh->GetSurface(i);
+		LevelMeshSurface* surface = surfaces[i];
 		if (surface->lightmapperAtlasPage != pageIndex)
 			continue;
 
diff --git a/src/common/rendering/vulkan/accelstructs/vk_lightmap.h b/src/common/rendering/vulkan/accelstructs/vk_lightmap.h
index 3fd8a0b8e2..ffbf1e853f 100644
--- a/src/common/rendering/vulkan/accelstructs/vk_lightmap.h
+++ b/src/common/rendering/vulkan/accelstructs/vk_lightmap.h
@@ -96,7 +96,7 @@ private:
 	void RenderAtlasImage(size_t pageIndex, const TArray<LevelMeshSurface*>& surfaces);
 	void ResolveAtlasImage(size_t pageIndex);
 	void BlurAtlasImage(size_t pageIndex);
-	void CopyAtlasImageResult(size_t pageIndex);
+	void CopyAtlasImageResult(size_t pageIndex, const TArray<LevelMeshSurface*>& surfaces);
 
 	LightmapImage CreateImage(int width, int height);
 
diff --git a/src/common/rendering/vulkan/vk_renderdevice.cpp b/src/common/rendering/vulkan/vk_renderdevice.cpp
index 7fd2f49e5b..8d3d44c2d7 100644
--- a/src/common/rendering/vulkan/vk_renderdevice.cpp
+++ b/src/common/rendering/vulkan/vk_renderdevice.cpp
@@ -531,17 +531,20 @@ void VulkanRenderDevice::PrintStartupLog()
 	Printf("Min. uniform buffer offset alignment: %" PRIu64 "\n", limits.minUniformBufferOffsetAlignment);
 }
 
+LevelMesh* lastMesh = nullptr; // Temp hack; Since this function is called every frame we only want to do this once
+
 void VulkanRenderDevice::SetLevelMesh(LevelMesh* mesh)
 {
 	mRaytrace->SetLevelMesh(mesh);
 
-	static LevelMesh* lastMesh = nullptr; // Temp hack; Since this function is called every frame we only want to do this once
 	if (lastMesh != mesh && mesh->GetSurfaceCount() > 0)
 	{
 		lastMesh = mesh;
 
 		mesh->UpdateLightLists();
+		GetTextureManager()->CreateLightmap(mesh->LMTextureSize, mesh->LMTextureCount);
 
+#if 0 // full lightmap generation
 		TArray<LevelMeshSurface*> surfaces;
 		surfaces.Reserve(mesh->GetSurfaceCount());
 		for (unsigned i = 0, count = mesh->GetSurfaceCount(); i < count; ++i)
@@ -549,8 +552,23 @@ void VulkanRenderDevice::SetLevelMesh(LevelMesh* mesh)
 			surfaces[i] = mesh->GetSurface(i);
 		}
 
-		GetTextureManager()->CreateLightmap(mesh->LMTextureSize, mesh->LMTextureCount);
 		GetLightmap()->Raytrace(mesh, surfaces);
+#else
+		GetLightmap()->Raytrace(mesh, {});
+#endif
+	}
+}
+
+void VulkanRenderDevice::UpdateLightmaps(const TArray<LevelMeshSurface*>& surfaces)
+{
+	if (surfaces.Size() > 0)
+	{
+		auto levelMesh = lastMesh; // There's nothing more permanent than a temporary solution
+
+		if (levelMesh)
+		{
+			GetLightmap()->Raytrace(levelMesh, surfaces);
+		}
 	}
 }
 
diff --git a/src/common/rendering/vulkan/vk_renderdevice.h b/src/common/rendering/vulkan/vk_renderdevice.h
index 6702f46c3c..9de2e53813 100644
--- a/src/common/rendering/vulkan/vk_renderdevice.h
+++ b/src/common/rendering/vulkan/vk_renderdevice.h
@@ -63,6 +63,7 @@ public:
 	void AmbientOccludeScene(float m5) override;
 	void SetSceneRenderTarget(bool useSSAO) override;
 	void SetLevelMesh(LevelMesh* mesh) override;
+	void UpdateLightmaps(const TArray<LevelMeshSurface*>& surfaces) override;
 	void SetShadowMaps(const TArray<float>& lights, hwrenderer::LevelAABBTree* tree, bool newTree) override;
 	void SetSaveBuffers(bool yes) override;
 	void ImageTransitionScene(bool unknown) override;
diff --git a/src/rendering/hwrenderer/doom_levelmesh.cpp b/src/rendering/hwrenderer/doom_levelmesh.cpp
index da7c6a79e3..598c5e376f 100644
--- a/src/rendering/hwrenderer/doom_levelmesh.cpp
+++ b/src/rendering/hwrenderer/doom_levelmesh.cpp
@@ -23,6 +23,18 @@ CCMD(dumplevelmesh)
 	}
 }
 
+CCMD(invalidatelightmap)
+{
+	int count = 0;
+	for (auto& surface : level.levelMesh->Surfaces)
+	{
+		if (!surface.needsUpdate)
+			++count;
+		surface.needsUpdate = true;
+	}
+	Printf("Marked %d out of %d surfaces for update.\n", count, level.levelMesh->Surfaces.Size());
+}
+
 DoomLevelMesh::DoomLevelMesh(FLevelLocals &doomMap)
 {
 	SunColor = doomMap.SunColor; // TODO keep only one copy?
diff --git a/src/rendering/hwrenderer/hw_entrypoint.cpp b/src/rendering/hwrenderer/hw_entrypoint.cpp
index 55a4fe8d5b..9e7b09724b 100644
--- a/src/rendering/hwrenderer/hw_entrypoint.cpp
+++ b/src/rendering/hwrenderer/hw_entrypoint.cpp
@@ -124,6 +124,7 @@ sector_t* RenderViewpoint(FRenderViewpoint& mainvp, AActor* camera, IntRect* bou
 		screen->mShadowMap->SetCollectLights(nullptr);
 	}
 
+	RenderState.ClearVisibleSurfaceList();
 	screen->SetLevelMesh(camera->Level->levelMesh);
 
 	static HWDrawContext mainthread_drawctx;
@@ -197,6 +198,8 @@ sector_t* RenderViewpoint(FRenderViewpoint& mainvp, AActor* camera, IntRect* bou
 			screen->NextEye(eyeCount);
 	}
 
+	screen->UpdateLightmaps(RenderState.GetVisibleSurfaceList());
+
 	return mainvp.sector;
 }
 
diff --git a/src/rendering/hwrenderer/scene/hw_flats.cpp b/src/rendering/hwrenderer/scene/hw_flats.cpp
index 0b878da758..8130f694ef 100644
--- a/src/rendering/hwrenderer/scene/hw_flats.cpp
+++ b/src/rendering/hwrenderer/scene/hw_flats.cpp
@@ -192,6 +192,10 @@ void HWFlat::DrawSubsectors(HWDrawInfo *di, FRenderState &state)
 	}
 	state.SetLightIndex(dynlightindex);
 
+	for (auto& subsector : section->subsectors)
+	{
+		state.PushVisibleSurface(subsector->lightmap[ceiling ? 1 : 0][0]);
+	}
 
 	state.DrawIndexed(DT_Triangles, iboindex + section->vertexindex, section->vertexcount);
 	flatvertices += section->vertexcount;