PaperMC/patches/unapplied/server/0848-Use-single-player-info-update-packet-on-join.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Sun, 8 Jan 2023 17:38:28 -0800
Subject: [PATCH] Use single player info update packet on join


diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index 5f1c31323d58cdc4419cf5f8870a8acf121c7669..0c87fff227448f7f88e3377989b1091e4badcc53 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -3339,7 +3339,7 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
         this.signedMessageDecoder = session.createMessageDecoder(this.player.getUUID());
         this.chatMessageChain.append(() -> {
             this.player.setChatSession(session);
-            this.server.getPlayerList().broadcastAll(new ClientboundPlayerInfoUpdatePacket(EnumSet.of(ClientboundPlayerInfoUpdatePacket.Action.INITIALIZE_CHAT), List.of(this.player)));
+            this.server.getPlayerList().broadcastAll(new ClientboundPlayerInfoUpdatePacket(EnumSet.of(ClientboundPlayerInfoUpdatePacket.Action.INITIALIZE_CHAT), List.of(this.player)), this.player); // Paper - Use single player info update packet on join
         });
     }
 
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index 1478def0ba4bc02c1c466d80cc2b90919612c18a..0747b0042446271385371f1ca9c8fefdebd851b8 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -359,6 +359,7 @@ public abstract class PlayerList {
         // CraftBukkit start - sendAll above replaced with this loop
         ClientboundPlayerInfoUpdatePacket packet = ClientboundPlayerInfoUpdatePacket.createPlayerInitializing(List.of(player));
 
+        final List<ServerPlayer> onlinePlayers = Lists.newArrayListWithExpectedSize(this.players.size() - 1); // Paper - Use single player info update packet on join
         for (int i = 0; i < this.players.size(); ++i) {
             ServerPlayer entityplayer1 = (ServerPlayer) this.players.get(i);
 
@@ -366,12 +367,17 @@ public abstract class PlayerList {
                 entityplayer1.connection.send(packet);
             }
 
-            if (!bukkitPlayer.canSee(entityplayer1.getBukkitEntity())) {
+            if (entityplayer1 == player || !bukkitPlayer.canSee(entityplayer1.getBukkitEntity())) { // Paper - Use single player info update packet on join; Don't include joining player
                 continue;
             }
 
-            player.connection.send(ClientboundPlayerInfoUpdatePacket.createPlayerInitializing(List.of(entityplayer1)));
+            onlinePlayers.add(entityplayer1); // Paper - Use single player info update packet on join
         }
+        // Paper start - Use single player info update packet on join
+        if (!onlinePlayers.isEmpty()) {
+            player.connection.send(ClientboundPlayerInfoUpdatePacket.createPlayerInitializing(onlinePlayers));
+        }
+        // Paper end - Use single player info update packet on join
         player.sentListPacket = true;
         player.supressTrackerForLogin = false; // Paper - Fire PlayerJoinEvent when Player is actually ready
         ((ServerLevel)player.level()).getChunkSource().chunkMap.addEntity(player); // Paper - Fire PlayerJoinEvent when Player is actually ready; track entity now