Send only changed node metadata to clients instead of whole mapblock (#5268)

Includes newer style changes and fixes by est31

Improve the block position de-serialization
Add type NodeMetadataMap

1 files changed, 76 insertions, 11 deletions

diff --git a/src/server.cpp b/src/server.cpp
index f9550c54f..f1fbe8668 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -861,6 +861,8 @@ void Server::AsyncRunStep(bool initial_step)
 		// We'll log the amount of each
 		Profiler prof;
 
+		std::list<v3s16> node_meta_updates;
+
 		while (!m_unsent_map_edit_queue.empty()) {
 			MapEditEvent* event = m_unsent_map_edit_queue.front();
 			m_unsent_map_edit_queue.pop();
@@ -883,11 +885,22 @@ void Server::AsyncRunStep(bool initial_step)
 				sendRemoveNode(event->p, &far_players,
 						disable_single_change_sending ? 5 : 30);
 				break;
-			case MEET_BLOCK_NODE_METADATA_CHANGED:
-				infostream << "Server: MEET_BLOCK_NODE_METADATA_CHANGED" << std::endl;
-						prof.add("MEET_BLOCK_NODE_METADATA_CHANGED", 1);
-						m_clients.markBlockposAsNotSent(event->p);
+			case MEET_BLOCK_NODE_METADATA_CHANGED: {
+				verbosestream << "Server: MEET_BLOCK_NODE_METADATA_CHANGED" << std::endl;
+				prof.add("MEET_BLOCK_NODE_METADATA_CHANGED", 1);
+				if (!event->is_private_change) {
+					// Don't send the change yet. Collect them to eliminate dupes.
+					node_meta_updates.remove(event->p);
+					node_meta_updates.push_back(event->p);
+				}
+
+				if (MapBlock *block = m_env->getMap().getBlockNoCreateNoEx(
+						getNodeBlockPos(event->p))) {
+					block->raiseModified(MOD_STATE_WRITE_NEEDED,
+						MOD_REASON_REPORT_META_CHANGE);
+				}
 				break;
+			}
 			case MEET_OTHER:
 				infostream << "Server: MEET_OTHER" << std::endl;
 				prof.add("MEET_OTHER", 1);
@@ -931,6 +944,9 @@ void Server::AsyncRunStep(bool initial_step)
 			prof.print(verbosestream);
 		}
 
+		// Send all metadata updates
+		if (node_meta_updates.size())
+			sendMetadataChanged(node_meta_updates);
 	}
 
 	/*
@@ -1224,6 +1240,7 @@ Inventory* Server::getInventory(const InventoryLocation &loc)
 	}
 	return NULL;
 }
+
 void Server::setInventoryModified(const InventoryLocation &loc, bool playerSend)
 {
 	switch(loc.type){
@@ -1248,13 +1265,10 @@ void Server::setInventoryModified(const InventoryLocation &loc, bool playerSend)
 		break;
 	case InventoryLocation::NODEMETA:
 	{
-		v3s16 blockpos = getNodeBlockPos(loc.p);
-
-		MapBlock *block = m_env->getMap().getBlockNoCreateNoEx(blockpos);
-		if (block)
-			block->raiseModified(MOD_STATE_WRITE_NEEDED);
-
-		m_clients.markBlockposAsNotSent(blockpos);
+		MapEditEvent event;
+		event.type = MEET_BLOCK_NODE_METADATA_CHANGED;
+		event.p = loc.p;
+		m_env->getMap().dispatchEvent(&event);
 	}
 		break;
 	case InventoryLocation::DETACHED:
@@ -2159,6 +2173,57 @@ void Server::sendAddNode(v3s16 p, MapNode n, std::unordered_set<u16> *far_player
 	m_clients.unlock();
 }
 
+void Server::sendMetadataChanged(const std::list<v3s16> &meta_updates, float far_d_nodes)
+{
+	float maxd = far_d_nodes * BS;
+	NodeMetadataList meta_updates_list(false);
+	std::vector<session_t> clients = m_clients.getClientIDs();
+
+	m_clients.lock();
+
+	for (session_t i : clients) {
+		RemoteClient *client = m_clients.lockedGetClientNoEx(i);
+		if (!client)
+			continue;
+
+		ServerActiveObject *player = m_env->getActiveObject(i);
+		v3f player_pos = player ? player->getBasePosition() : v3f();
+
+		for (const v3s16 &pos : meta_updates) {
+			NodeMetadata *meta = m_env->getMap().getNodeMetadata(pos);
+
+			if (!meta)
+				continue;
+
+			v3s16 block_pos = getNodeBlockPos(pos);
+			if (!client->isBlockSent(block_pos) || (player &&
+					player_pos.getDistanceFrom(intToFloat(pos, BS)) > maxd)) {
+				client->SetBlockNotSent(block_pos);
+				continue;
+			}
+
+			// Add the change to send list
+			meta_updates_list.set(pos, meta);
+		}
+		if (meta_updates_list.size() == 0)
+			continue;
+
+		// Send the meta changes
+		std::ostringstream os(std::ios::binary);
+		meta_updates_list.serialize(os, client->net_proto_version, false, true);
+		std::ostringstream oss(std::ios::binary);
+		compressZlib(os.str(), oss);
+
+		NetworkPacket pkt(TOCLIENT_NODEMETA_CHANGED, 0);
+		pkt.putLongString(oss.str());
+		m_clients.send(i, 0, &pkt, true);
+
+		meta_updates_list.clear();
+	}
+
+	m_clients.unlock();
+}
+
 void Server::SendBlockNoLock(session_t peer_id, MapBlock *block, u8 ver,
 		u16 net_proto_version)
 {