feat: Optimize ServerWaypointManager when locator bar is disabled

The waypoint system  iterates over each player for running waypoint calculations. This, most notably, is done on setPosRaw which is executed twice for each player (one for non players).
This results in every time a player moves, it iterates over each player twice.

So instead, we cache the game rule and instead use this to prevent iterating over all the players and avoid the redundant connection logic checks.

This performance issue is most noticeable with many players on the same level.

Author: Owen1212055

paper-server/patches/features/0001-Moonrise-optimisation-patches.patch

@@ -23838,7 +23838,7 @@ index 3c1490ac7c259da04031db2f170e0c0a5f512191..470d7c770ae9d045b97e2df145cfe3cf
          }
      }
 diff --git a/net/minecraft/server/MinecraftServer.java b/net/minecraft/server/MinecraftServer.java
-index 54dc5f5898df9895c82bbc318d63d2f485bf9574..1b064f00c33712c3d2d85ed8520f1eda02abfbf9 100644
+index 9566334f019ff3c9469f06c784d122b5d35f3e24..e11862c7e0617acfb36212cfe349bdade3a5164b 100644
 --- a/net/minecraft/server/MinecraftServer.java
 +++ b/net/minecraft/server/MinecraftServer.java
 @@ -191,7 +191,7 @@ import net.minecraft.world.scores.ScoreboardSaveData;
@@ -27004,7 +27004,7 @@ index de75dda2e6f17f0ae6e7f6a5620fd3eac9d389e5..6774d12d04fa848624fb8bf7a3c2b8bc
          List<Entity> passengers = this.entity.getPassengers();
          if (!passengers.equals(this.lastPassengers)) {
 diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
-index 71446ef19c560f67d22697941973326e2b81bb60..8c954add1949777b4f5658064eb7cd381d542140 100644
+index d0742abe193dfd8eeeea69a53f78d809d26efabe..96e45eab1e8cf857f5068e911070259866d8bdcb 100644
 --- a/net/minecraft/server/level/ServerLevel.java
 +++ b/net/minecraft/server/level/ServerLevel.java
 @@ -182,7 +182,7 @@ import net.minecraft.world.waypoints.WaypointTransmitter;
@@ -27400,7 +27400,7 @@ index 71446ef19c560f67d22697941973326e2b81bb60..8c954add1949777b4f5658064eb7cd38
              , savedDataStorage // Paper - initialize SavedDataStorage earlier
          );
 @@ -471,6 +715,20 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
-         this.waypointManager = new ServerWaypointManager();
+         this.waypointManager = new ServerWaypointManager(this); // Paper - optimize ServerWaypointManager with locator bar disabled
          this.environmentAttributes = EnvironmentAttributeSystem.builder().addDefaultLayers(this).build();
          this.updateSkyBrightness();
 +        // Paper start - rewrite chunk system

paper-server/patches/sources/net/minecraft/server/MinecraftServer.java.patch

@@ -1533,7 +1533,7 @@
                  player.connection.send(new ClientboundEntityEventPacket(player, event));
              }
          } else if (rule == GameRules.LIMITED_CRAFTING || rule == GameRules.IMMEDIATE_RESPAWN) {
-@@ -2131,19 +_,20 @@
+@@ -2131,19 +_,21 @@
                  ? ClientboundGameEventPacket.LIMITED_CRAFTING
                  : ClientboundGameEventPacket.IMMEDIATE_RESPAWN;
              ClientboundGameEventPacket packet = new ClientboundGameEventPacket(eventType, (Boolean)value ? 1.0F : 0.0F);
@@ -1543,6 +1543,7 @@
 -            this.getAllLevels().forEach(level -> {
 +            // this.getAllLevels().forEach(level -> { // Paper - per-world game rules
                  ServerWaypointManager waypointManager = level.getWaypointManager();
++                waypointManager.locatorBarEnabled = (Boolean) value; // Paper - optimize ServerWaypointManager with locator bar disabled
                  if ((Boolean)value) {
                      level.players().forEach(waypointManager::updatePlayer);
                  } else {

paper-server/patches/sources/net/minecraft/server/level/ServerLevel.java.patch

@@ -241,8 +241,12 @@
              generator,
              this.chunkSource.randomState(),
              this,
-@@ -303,7 +_,15 @@
-         this.waypointManager = new ServerWaypointManager();
+@@ -300,10 +_,18 @@
+ 
+         this.sleepStatus = new SleepStatus();
+         this.gameEventDispatcher = new GameEventDispatcher(this);
+-        this.waypointManager = new ServerWaypointManager();
++        this.waypointManager = new ServerWaypointManager(this); // Paper - optimize ServerWaypointManager with locator bar disabled
          this.environmentAttributes = EnvironmentAttributeSystem.builder().addDefaultLayers(this).build();
          this.updateSkyBrightness();
 -    }

paper-server/patches/sources/net/minecraft/server/waypoints/ServerWaypointManager.java.patch

@@ -0,0 +1,72 @@
+--- a/net/minecraft/server/waypoints/ServerWaypointManager.java
++++ b/net/minecraft/server/waypoints/ServerWaypointManager.java
+@@ -19,11 +_,19 @@
+     private final Set<WaypointTransmitter> waypoints = new HashSet<>();
+     private final Set<ServerPlayer> players = new HashSet<>();
+     private final Table<ServerPlayer, WaypointTransmitter, WaypointTransmitter.Connection> connections = HashBasedTable.create();
++    // Paper start - optimize ServerWaypointManager with locator bar disabled
++    public boolean locatorBarEnabled; // Avoid a gamerule lookup for each player
++
++    public ServerWaypointManager(net.minecraft.server.level.ServerLevel serverLevel) {
++        this.locatorBarEnabled = serverLevel.getGameRules().get(GameRules.LOCATOR_BAR);
++    }
++    // Paper end - optimize ServerWaypointManager with locator bar disabled
+ 
+     @Override
+     public void trackWaypoint(final WaypointTransmitter waypoint) {
+         this.waypoints.add(waypoint);
+ 
++        if (!this.locatorBarEnabled) return; // Paper - optimize ServerWaypointManager with locator bar disabled
+         for (ServerPlayer player : this.players) {
+             this.createConnection(player, waypoint);
+         }
+@@ -31,6 +_,7 @@
+ 
+     @Override
+     public void updateWaypoint(final WaypointTransmitter waypoint) {
++        if (!this.locatorBarEnabled) return; // Paper - optimize ServerWaypointManager with locator bar disabled
+         if (this.waypoints.contains(waypoint)) {
+             Map<ServerPlayer, WaypointTransmitter.Connection> playerConnection = Tables.transpose(this.connections).row(waypoint);
+             SetView<ServerPlayer> potentialPlayers = Sets.difference(this.players, playerConnection.keySet());
+@@ -55,9 +_,11 @@
+     public void addPlayer(final ServerPlayer player) {
+         this.players.add(player);
+ 
++        if (this.locatorBarEnabled) { // Paper - optimize ServerWaypointManager with locator bar disabled
+         for (WaypointTransmitter waypoint : this.waypoints) {
+             this.createConnection(player, waypoint);
+         }
++        } // Paper - optimize ServerWaypointManager with locator bar disabled
+ 
+         if (player.isTransmittingWaypoint()) {
+             this.trackWaypoint((WaypointTransmitter)player);
+@@ -65,6 +_,7 @@
+     }
+ 
+     public void updatePlayer(final ServerPlayer player) {
++        if (!this.locatorBarEnabled) return; // Paper - optimize ServerWaypointManager with locator bar disabled
+         Map<WaypointTransmitter, WaypointTransmitter.Connection> waypointConnections = this.connections.row(player);
+         SetView<WaypointTransmitter> potentialWaypoints = Sets.difference(this.waypoints, waypointConnections.keySet());
+ 
+@@ -92,6 +_,7 @@
+     }
+ 
+     public void remakeConnections(final WaypointTransmitter waypoint) {
++        if (!this.locatorBarEnabled) return; // Paper - optimize ServerWaypointManager with locator bar disabled
+         for (ServerPlayer player : this.players) {
+             this.createConnection(player, waypoint);
+         }
+@@ -101,8 +_,11 @@
+         return this.waypoints;
+     }
+ 
+-    private static boolean isLocatorBarEnabledFor(final ServerPlayer player) {
+-        return player.level().getGameRules().get(GameRules.LOCATOR_BAR);
++    // Paper start - optimize ServerWaypointManager with locator bar disabled
++    // Avoid a gamerule lookup for each player
++    private boolean isLocatorBarEnabledFor(final ServerPlayer player) {
++        return locatorBarEnabled;
++    // Paper end - optimize ServerWaypointManager with locator bar disabled
+     }
+ 
+     private void createConnection(final ServerPlayer player, final WaypointTransmitter waypoint) {