Revert patch 58f036ad that causes object duplication (which tried to fix...

Revert patch 58f036ad that causes object duplication (which tried to fix objects getting hidden from client) and fix the original problem correctly. This fixes the second distinct object duplication bug.

src/environment.cpp

@@ -1417,8 +1417,8 @@ void ServerEnvironment::getAddedActiveObjects(v3s16 pos, s16 radius,
 		ServerActiveObject *object = i->second;
 		if(object == NULL)
 			continue;
-		// Discard if removed
-		if(object->m_removed)
+		// Discard if removed or deactivating
+		if(object->m_removed || object->m_pending_deactivation)
 			continue;
 		if(object->unlimitedTransferDistance() == false){
 			// Discard if too far
@@ -1468,7 +1468,7 @@ void ServerEnvironment::getRemovedActiveObjects(v3s16 pos, s16 radius,
 			continue;
 		}
 
-		if(object->m_removed)
+		if(object->m_removed || object->m_pending_deactivation)
 		{
 			removed_objects.insert(id);
 			continue;
@@ -1556,9 +1556,8 @@ u16 ServerEnvironment::addActiveObjectRaw(ServerActiveObject *object,
 		StaticObject s_obj(object->getType(), objectpos, staticdata);
 		// Add to the block where the object is located in
 		v3s16 blockpos = getNodeBlockPos(floatToInt(objectpos, BS));
-		MapBlock *block = m_map->getBlockNoCreateNoEx(blockpos);
-		if(block)
-		{
+		MapBlock *block = m_map->emergeBlock(blockpos);
+		if(block){
 			block->m_static_objects.m_active[object->getId()] = s_obj;
 			object->m_static_exists = true;
 			object->m_static_block = blockpos;
@@ -1566,11 +1565,10 @@ u16 ServerEnvironment::addActiveObjectRaw(ServerActiveObject *object,
 			if(set_changed)
 				block->raiseModified(MOD_STATE_WRITE_NEEDED, 
 						"addActiveObjectRaw");
-		}
-		else{
+		} else {
 			v3s16 p = floatToInt(objectpos, BS);
 			errorstream<<"ServerEnvironment::addActiveObjectRaw(): "
-					<<"could not find block for storing id="<<object->getId()
+					<<"could not emerge block for storing id="<<object->getId()
 					<<" statically (pos="<<PP(p)<<")"<<std::endl;
 		}
 	}
@@ -1616,18 +1614,39 @@ void ServerEnvironment::removeRemovedObjects()
 			if (block) {
 				block->m_static_objects.remove(id);
 				block->raiseModified(MOD_STATE_WRITE_NEEDED,
-						"removeRemovedObjects");
+						"removeRemovedObjects/remove");
 				obj->m_static_exists = false;
 			} else {
-				infostream << "failed to emerge block from which "
-					"an object to be removed was loaded from. id="<<id<<std::endl;
+				infostream<<"Failed to emerge block from which an object to "
+						<<"be removed was loaded from. id="<<id<<std::endl;
 			}
 		}
 
-		// If m_known_by_count > 0, don't actually remove.
+		// If m_known_by_count > 0, don't actually remove. On some future
+		// invocation this will be 0, which is when removal will continue.
 		if(obj->m_known_by_count > 0)
 			continue;
-		
+
+		/*
+			Move static data from active to stored if not marked as removed
+		*/
+		if(obj->m_static_exists && !obj->m_removed){
+			MapBlock *block = m_map->emergeBlock(obj->m_static_block, false);
+			if (block) {
+				std::map<u16, StaticObject>::iterator i =
+						block->m_static_objects.m_active.find(id);
+				if(i != block->m_static_objects.m_active.end()){
+					block->m_static_objects.m_stored.push_back(i->second);
+					block->m_static_objects.m_active.erase(id);
+					block->raiseModified(MOD_STATE_WRITE_NEEDED,
+							"removeRemovedObjects/deactivate");
+				}
+			} else {
+				infostream<<"Failed to emerge block from which an object to "
+						<<"be deactivated was loaded from. id="<<id<<std::endl;
+			}
+		}
+
 		// Tell the object about removal
 		obj->removingFromEnvironment();
 		// Deregister in scripting api
@@ -1708,10 +1727,9 @@ void ServerEnvironment::activateObjects(MapBlock *block, u32 dtime_s)
 				"large amount of objects");
 		return;
 	}
-	// A list for objects that couldn't be converted to active for some
-	// reason. They will be stored back.
+
+	// Activate stored objects
 	std::list<StaticObject> new_stored;
-	// Loop through stored static objects
 	for(std::list<StaticObject>::iterator
 			i = block->m_static_objects.m_stored.begin();
 			i != block->m_static_objects.m_stored.end(); ++i)
@@ -1750,6 +1768,19 @@ void ServerEnvironment::activateObjects(MapBlock *block, u32 dtime_s)
 		StaticObject &s_obj = *i;
 		block->m_static_objects.m_stored.push_back(s_obj);
 	}
+
+	// Turn the active counterparts of activated objects not pending for
+	// deactivation
+	for(std::map<u16, StaticObject>::iterator
+			i = block->m_static_objects.m_active.begin();
+			i != block->m_static_objects.m_active.end(); ++i)
+	{
+		u16 id = i->first;
+		ServerActiveObject *object = getActiveObject(id);
+		assert(object);
+		object->m_pending_deactivation = false;
+	}
+
 	/*
 		Note: Block hasn't really been modified here.
 		The objects have just been activated and moved from the stored
@@ -1910,6 +1941,8 @@ void ServerEnvironment::deactivateFarObjects(bool force_delete)
 				block = m_map->emergeBlock(blockpos);
 			} catch(InvalidPositionException &e){
 				// Handled via NULL pointer
+				// NOTE: emergeBlock's failure is usually determined by it
+				//       actually returning NULL
 			}
 
 			if(block)
@@ -1923,17 +1956,21 @@ void ServerEnvironment::deactivateFarObjects(bool force_delete)
 							<<" Forcing delete."<<std::endl;
 					force_delete = true;
 				} else {
-					// If static counterpart already exists, remove it first.
-					// This shouldn't happen, but happens rarely for some
-					// unknown reason. Unsuccessful attempts have been made to
-					// find said reason.
+					// If static counterpart already exists in target block,
+					// remove it first.
+					// This shouldn't happen because the object is removed from
+					// the previous block before this according to
+					// obj->m_static_block, but happens rarely for some unknown
+					// reason. Unsuccessful attempts have been made to find
+					// said reason.
 					if(id && block->m_static_objects.m_active.find(id) != block->m_static_objects.m_active.end()){
 						infostream<<"ServerEnv: WARNING: Performing hack #83274"
 								<<std::endl;
 						block->m_static_objects.remove(id);
 					}
-					//store static data
-					block->m_static_objects.insert(0, s_obj);
+					// Store static data
+					u16 store_id = pending_delete ? id : 0;
+					block->m_static_objects.insert(store_id, s_obj);
 					
 					// Only mark block as modified if data changed considerably
 					if(shall_be_written)