Fix deactivated lightmap light not working

src/common/rendering/hwrenderer/data/hw_levelmesh.h

@@ -227,7 +227,7 @@ public:
 	// Lightmap tiles and their locations in the texture atlas
 	struct
 	{
-		int TextureCount = 0;
+		int TextureCount = 10; // To do: remove all the limits and instead resize GPU resources if they are exhausted. Too difficult to calculate it all up front.
 		int TextureSize = 1024;
 		TArray<uint16_t> TextureData;
 		uint16_t SampleDistance = 8;

src/common/rendering/hwrenderer/data/hw_lightmaptile.h

@@ -26,6 +26,14 @@ struct LightmapTileBinding
 	}
 };
 
+enum TileUpdatePolicy
+{
+	MapChanges,
+	AlwaysUltraQuality,
+	Always,
+	MapChangesUltraQuality
+};
+
 struct LightmapTile
 {
 	// Surface location in lightmap texture

src/levelmeshhelper.cpp

@@ -88,6 +88,16 @@ void UpdateLevelMesh::SectorLightThinkerDestroyed(sector_t* sector, DLighting* l
 	PropagateCorrelations(this, &UpdateLevelMesh::OnSectorLightThinkerDestroyed, sector, lightthinker);
 }
 
+void UpdateLevelMesh::SectorLightListChanged(sector_t* sector)
+{
+	OnSectorLightListChanged(sector);
+}
+
+void UpdateLevelMesh::SideLightListChanged(side_t* side)
+{
+	OnSideLightListChanged(side);
+}
+
 struct NullLevelMeshUpdater : UpdateLevelMesh
 {
 	void OnFloorHeightChanged(sector_t* sector) override {}
@@ -105,6 +115,9 @@ struct NullLevelMeshUpdater : UpdateLevelMesh
 	void OnSectorLightChanged(sector_t* sector) override {}
 	void OnSectorLightThinkerCreated(sector_t* sector, DLighting* lightthinker) override {}
 	void OnSectorLightThinkerDestroyed(sector_t* sector, DLighting* lightthinker) override {}
+
+	void OnSectorLightListChanged(sector_t* sector) override {}
+	void OnSideLightListChanged(side_t* side) override {}
 };
 
 static NullLevelMeshUpdater nullUpdater;

src/levelmeshhelper.h

@@ -24,7 +24,10 @@ struct UpdateLevelMesh
 	void SectorLightChanged(sector_t* sector);
 	void SectorLightThinkerCreated(sector_t* sector, DLighting* lightthinker);
 	void SectorLightThinkerDestroyed(sector_t* sector, DLighting* lightthinker);
-	
+
+	void SectorLightListChanged(sector_t* sector);
+	void SideLightListChanged(side_t* side);
+
 	//raw
 	virtual void OnFloorHeightChanged(sector_t *sector) = 0;
 	virtual void OnCeilingHeightChanged(sector_t *sector) = 0;
@@ -41,6 +44,9 @@ struct UpdateLevelMesh
 	virtual void OnSectorLightChanged(sector_t* sector) = 0;
 	virtual void OnSectorLightThinkerCreated(sector_t* sector, DLighting* lightthinker) = 0;
 	virtual void OnSectorLightThinkerDestroyed(sector_t* sector, DLighting* lightthinker) = 0;
+
+	virtual void OnSectorLightListChanged(sector_t* sector) = 0;
+	virtual void OnSideLightListChanged(side_t* side) = 0;
 };
 
 extern UpdateLevelMesh* LevelMeshUpdater;

src/playsim/a_dynlight.cpp

@@ -95,6 +95,7 @@ static void MarkTilesForUpdate(FLevelLocals * Level, FLightNode * touching_sides
 	{
 		while(touching_sides)
 		{
+			LevelMeshUpdater->SideLightListChanged(touching_sides->targLine);
 			MarkTilesForUpdate(Level, touching_sides->targLine->LightmapTiles);
 
 			touching_sides = touching_sides->nextTarget;
@@ -102,6 +103,7 @@ static void MarkTilesForUpdate(FLevelLocals * Level, FLightNode * touching_sides
 	
 		while(touching_sector)
 		{
+			LevelMeshUpdater->SectorLightListChanged(touching_sector->targSection->sector);
 			for(subsector_t * ss : touching_sector->targSection->subsectors)
 			{
 				MarkTilesForUpdate(Level, ss->LightmapTiles[0]);

src/rendering/hwrenderer/doom_levelmesh.cpp

@@ -706,22 +706,48 @@ void DoomLevelMesh::OnSectorLightThinkerDestroyed(sector_t* sector, DLighting* l
 {
 }
 
+void DoomLevelMesh::OnSectorLightListChanged(sector_t* sector)
+{
+	// To do: we don't have to recreate the entire surface. Updating just the light list would do.
+	UpdateFlat(sector->Index(), SurfaceUpdateType::Full);
+}
+
+void DoomLevelMesh::OnSideLightListChanged(side_t* side)
+{
+	// To do: we don't have to recreate the entire surface. Updating just the light list would do.
+	UpdateSide(side->Index(), SurfaceUpdateType::Full);
+}
+
 void DoomLevelMesh::UpdateSide(unsigned int sideIndex, SurfaceUpdateType updateType)
 {
-	if (Sides[sideIndex].UpdateType == SurfaceUpdateType::None)
+	SurfaceUpdateType value = Sides[sideIndex].UpdateType;
+	if (value == SurfaceUpdateType::None)
 	{
+		// First update request
 		SideUpdateList.Push(sideIndex);
 		Sides[sideIndex].UpdateType = updateType;
 	}
+	else if (value != updateType)
+	{
+		// Upgrade to full update if we get multiple upgrade requests of different types
+		Sides[sideIndex].UpdateType = SurfaceUpdateType::Full;
+	}
 }
 
 void DoomLevelMesh::UpdateFlat(unsigned int sectorIndex, SurfaceUpdateType updateType)
 {
-	if (Flats[sectorIndex].UpdateType == SurfaceUpdateType::None)
+	SurfaceUpdateType value = Flats[sectorIndex].UpdateType;
+	if (value == SurfaceUpdateType::None)
 	{
+		// First update request
 		FlatUpdateList.Push(sectorIndex);
 		Flats[sectorIndex].UpdateType = updateType;
 	}
+	else if (value != updateType)
+	{
+		// Upgrade to full update if we get multiple upgrade requests of different types
+		Flats[sectorIndex].UpdateType = SurfaceUpdateType::Full;
+	}
 }
 
 LightListAllocInfo DoomLevelMesh::CreateLightList(FLightNode* node, int portalgroup)

src/rendering/hwrenderer/doom_levelmesh.h

@@ -125,6 +125,8 @@ public:
 	void OnSectorLightChanged(sector_t* sector) override;
 	void OnSectorLightThinkerCreated(sector_t* sector, DLighting* lightthinker) override;
 	void OnSectorLightThinkerDestroyed(sector_t* sector, DLighting* lightthinker) override;
+	void OnSectorLightListChanged(sector_t* sector) override;
+	void OnSideLightListChanged(side_t* side) override;
 
 	void Reset(const LevelMeshLimits& limits) override
 	{