Add jitter calculations

bukkit/src/main/java/me/caseload/knockbacksync/listener/bukkit/BukkitPlayerJoinQuitListener.java

@@ -1,7 +1,7 @@
 package me.caseload.knockbacksync.listener.bukkit;
 
 import me.caseload.knockbacksync.listener.PlayerJoinQuitListener;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.player.BukkitPlayer;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;

common/src/main/java/me/caseload/knockbacksync/command/KnockbackSyncCommand.java

@@ -9,7 +9,7 @@
 import me.caseload.knockbacksync.command.subcommand.ToggleOffGroundSubcommand;
 import me.caseload.knockbacksync.command.subcommand.ToggleSubCommand;
 import me.caseload.knockbacksync.manager.ConfigManager;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 import me.caseload.knockbacksync.permission.PermissionChecker;
 import me.caseload.knockbacksync.util.ChatUtil;
@@ -59,7 +59,7 @@ public static LiteralArgumentBuilder<CommandSourceStack> build() {
                                     if (playerData.getPing() == null) {
                                         return Component.literal("Pong not received. Your estimated ping is " + playerData.getPlatformPlayer().getPing() + "ms.");
                                     } else {
-                                        return Component.literal("Your last ping packet took " + playerData.getPing() + "ms.");
+                                        return Component.literal("Your last ping packet took " + playerData.getPing() +  "ms. Jitter: " + playerData.getJitter() + "ms.");
                                     }
                                 }, false);
                             } else {
@@ -76,11 +76,9 @@ public static LiteralArgumentBuilder<CommandSourceStack> build() {
                                         if (playerData.getPing() == null) {
                                             return Component.literal("Pong not received. " + target.getDisplayName().getString() + "’s estimated ping is " + playerData.getEstimatedPing() + "ms.");
                                         } else {
-                                            return Component.literal(target.getDisplayName().getString() + "’s last ping packet took " + playerData.getPing() + "ms.");
+                                            return Component.literal(target.getDisplayName().getString() + "’s last ping packet took " + playerData.getPing() + "ms. Jitter: " + playerData.getJitter() + "ms.");
                                         }
                                     }, false);
-                                    return 1;
-                                })
                         )
                 )
                 .then(Commands.literal("reload")

common/src/main/java/me/caseload/knockbacksync/command/subcommand/ToggleSubCommand.java

@@ -6,7 +6,7 @@
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import me.caseload.knockbacksync.KnockbackSyncBase;
 import me.caseload.knockbacksync.manager.ConfigManager;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 import me.caseload.knockbacksync.permission.PermissionChecker;
 import me.caseload.knockbacksync.util.ChatUtil;

common/src/main/java/me/caseload/knockbacksync/listener/PlayerDamageListener.java

@@ -1,7 +1,7 @@
 package me.caseload.knockbacksync.listener;
 
 import me.caseload.knockbacksync.KnockbackSyncBase;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 import me.caseload.knockbacksync.player.PlatformPlayer;
 

common/src/main/java/me/caseload/knockbacksync/listener/PlayerJoinQuitListener.java

@@ -1,7 +1,7 @@
 package me.caseload.knockbacksync.listener;
 
 import me.caseload.knockbacksync.KnockbackSyncBase;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 import me.caseload.knockbacksync.player.PlatformPlayer;
 import me.caseload.knockbacksync.util.ChatUtil;

common/src/main/java/me/caseload/knockbacksync/listener/PlayerKnockbackListener.java

@@ -2,7 +2,7 @@
 
 import com.github.retrooper.packetevents.util.Vector3d;
 import me.caseload.knockbacksync.KnockbackSyncBase;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 import me.caseload.knockbacksync.player.PlatformPlayer;
 

common/src/main/java/me/caseload/knockbacksync/listener/packetevents/AttributeChangeListener.java

@@ -6,7 +6,7 @@
 import com.github.retrooper.packetevents.protocol.packettype.PacketType;
 import com.github.retrooper.packetevents.protocol.player.ClientVersion;
 import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerUpdateAttributes;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 import me.caseload.knockbacksync.util.MathUtil;
 

common/src/main/java/me/caseload/knockbacksync/listener/packetevents/PingReceiveListener.java

@@ -5,11 +5,9 @@
 import com.github.retrooper.packetevents.protocol.packettype.PacketType;
 import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientPong;
 import me.caseload.knockbacksync.KnockbackSyncBase;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 
-import java.util.UUID;
-
 public class PingReceiveListener extends PacketListenerAbstract {
 
     @Override
@@ -31,6 +29,10 @@ public void onPacketReceive(PacketReceiveEvent event) {
                 long ping = System.currentTimeMillis() - sendTime;
                 playerData.setPreviousPing(playerData.getPing());
                 playerData.setPing(ping);
+
+                playerData.getJitterCalculator().addPing(ping, id);
+                double jitter = playerData.getJitterCalculator().calculateJitter();
+                playerData.setJitter(jitter);
             }
         }
     }

common/src/main/java/me/caseload/knockbacksync/manager/ConfigManager.java

@@ -7,6 +7,7 @@
 import me.caseload.knockbacksync.ConfigWrapper;
 import me.caseload.knockbacksync.KnockbackSyncBase;
 import me.caseload.knockbacksync.Platform;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.runnable.PingRunnable;
 import me.caseload.knockbacksync.scheduler.AbstractTaskHandle;
 

common/src/main/java/me/caseload/knockbacksync/manager/PlayerDataManager.java

@@ -1,5 +1,6 @@
 package me.caseload.knockbacksync.manager;
 
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.util.FloodgateUtil;
 import me.caseload.knockbacksync.util.GeyserUtil;
 import org.jetbrains.annotations.NotNull;

common/src/main/java/me/caseload/knockbacksync/player/JitterCalculator.java

@@ -0,0 +1,68 @@
+package me.caseload.knockbacksync.player;
+
+import lombok.Getter;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+public class JitterCalculator {
+    private final int SAMPLE_SIZE = 15;
+    private final Queue<Long> pings = new LinkedList<>();
+    @Getter
+    private long sequenceNumber = 0;
+
+    public void addPing(long pingTime, long receivedSequence) {
+        pings.offer(pingTime);
+        if (pings.size() > SAMPLE_SIZE) {
+            pings.poll();
+        }
+
+        // Check for out-of-order packets
+        if (receivedSequence < sequenceNumber) {
+            // Handle out-of-order packet
+        }
+        sequenceNumber = receivedSequence;
+    }
+
+    public double calculateJitter() {
+        if (pings.size() < 2) return 0;
+
+        List<Long> sortedPings = new ArrayList<>(pings);
+        Collections.sort(sortedPings);
+
+        // Calculate IQR
+        int q1Index = sortedPings.size() / 4;
+        int q3Index = q1Index * 3;
+        long q1 = sortedPings.get(q1Index);
+        long q3 = sortedPings.get(q3Index);
+        long iqr = q3 - q1;
+
+        // Filter outliers
+        double lowerBound = q1 - 1.5 * iqr;
+        double upperBound = q3 + 1.5 * iqr;
+        List<Long> filteredPings = sortedPings.stream()
+                .filter(p -> p >= lowerBound && p <= upperBound)
+                .toList();
+
+        // Calculate standard deviation
+        double mean = filteredPings.stream().mapToLong(Long::longValue).average().orElse(0);
+        double variance = filteredPings.stream()
+                .mapToDouble(p -> Math.pow(p - mean, 2))
+                .average().orElse(0);
+        double stdDev = Math.sqrt(variance);
+
+        // Calculate mean jitter
+        double meanJitter = 0;
+        Long prevPing = null;
+        for (Long ping : filteredPings) {
+            if (prevPing != null) {
+                meanJitter += Math.abs(ping - prevPing);
+            }
+            prevPing = ping;
+        }
+        meanJitter /= (filteredPings.size() - 1);
+
+        // You can return different jitter metrics based on your needs
+        return stdDev; // or meanJitter, or both
+    }
+}

common/src/main/java/me/caseload/knockbacksync/manager/PlayerData.java → common/src/main/java/me/caseload/knockbacksync/player/PlayerData.java

@@ -1,4 +1,4 @@
-package me.caseload.knockbacksync.manager;
+package me.caseload.knockbacksync.player;
 
 import com.github.retrooper.packetevents.PacketEvents;
 import com.github.retrooper.packetevents.manager.player.PlayerManager;
@@ -8,13 +8,10 @@
 import com.github.retrooper.packetevents.protocol.world.states.type.StateTypes;
 import com.github.retrooper.packetevents.util.Vector3d;
 import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerPing;
-import io.netty.channel.Channel;
 import lombok.Getter;
 import lombok.Setter;
 import me.caseload.knockbacksync.KnockbackSyncBase;
-//import me.caseload.knockbacksync.player.BukkitPlayer;
-//import me.caseload.knockbacksync.player.FabricPlayer;
-import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.manager.CombatManager;
 import me.caseload.knockbacksync.world.PlatformWorld;
 import me.caseload.knockbacksync.scheduler.AbstractTaskHandle;
 import me.caseload.knockbacksync.util.MathUtil;
@@ -24,15 +21,19 @@
 import org.jetbrains.annotations.Nullable;
 
 import java.lang.reflect.Field;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Random;
-import java.util.UUID;
+import java.util.*;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
 
 @Getter
 public class PlayerData {
 
+
+    @Getter
+    private JitterCalculator jitterCalculator;
+    @Getter @Setter
+    private double jitter;
+
     private static final int PLUGIN_IDENTIFIER = 0x80000000; // Bit 31 set to 1 (negative)
     private static final int ID_MASK = 0x7FFF; // 15-bit mask
     private final AtomicInteger pingIdCounter = new AtomicInteger(0);
@@ -111,24 +112,6 @@ public PlayerData(PlatformPlayer platformPlayer) {
         PING_OFFSET = KnockbackSyncBase.INSTANCE.getConfigManager().getConfigWrapper().getInt("ping_offset", 25);
     }
 
-//    public PlayerData(Player player) {
-//        this.uuid = player.getUniqueId();
-//        this.user = PacketEvents.getAPI().getPlayerManager().getUser(player);
-//        this.platformPlayer = new BukkitPlayer(player);
-//        PING_OFFSET = KnockbackSyncBase.INSTANCE.getConfigManager().getConfigWrapper().getInt("ping_offset", 25);
-//    }
-
-//    public PlayerData(ServerPlayer player) {
-//        this.uuid = player.getUUID();
-        // ping listener doesn't work beause I can't get the user
-        // this exists temporarily until I fix packetevents
-//        Channel channel = (Channel) PacketEvents.getAPI().getProtocolManager().getChannel(uuid);
-//        this.user = PacketEvents.getAPI().getProtocolManager().getUser(channel);
-//        this.user = null; // PacketEvents.getAPI().getPlayerManager().getUser(player);
-//        this.platformPlayer = new FabricPlayer(player);
-//        PING_OFFSET = KnockbackSyncBase.INSTANCE.getConfigManager().getConfigWrapper().getInt("ping_offset", 25);
-//    }
-
     /**
      * Calculates the player's ping with compensation for lag spikes.
      * A hardcoded offset is applied for several reasons,
@@ -156,14 +139,14 @@ public boolean isPingIdOurs(int id) {
 //    We use the lower 15 bits for the counter, giving us 32,767 unique negative IDs before wrapping.
 //    The isPingIdOurs method checks if the ID is negative and if the upper 17 bits match our identifier.
 //    This should avoid conflicts with GrimAC which uses negative short range and other plugins which are mostly positive ranged
-    public void sendPing() {
-        if (user != null) {
-            int packetId = generatePingId();
-            timeline.put(packetId, System.currentTimeMillis());
-            WrapperPlayServerPing packet = new WrapperPlayServerPing(packetId);
-            user.sendPacket(packet);
-        }
+public void sendPing() {
+    if (user != null) {
+        int packetId = generatePingId();
+        timeline.put(packetId, System.currentTimeMillis());
+        WrapperPlayServerPing packet = new WrapperPlayServerPing(packetId);
+        user.sendPacket(packet);
     }
+}
 
     /**
      * Determines if the Player is on the ground clientside, but not serverside

common/src/main/java/me/caseload/knockbacksync/runnable/PingRunnable.java

@@ -2,7 +2,7 @@
 
 import me.caseload.knockbacksync.KnockbackSyncBase;
 import me.caseload.knockbacksync.manager.CombatManager;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 
 import java.util.UUID;

common/src/main/java/me/caseload/knockbacksync/stats/custom/PlayerVersionsPie.java

@@ -1,10 +1,9 @@
 package me.caseload.knockbacksync.stats.custom;
 
 import me.caseload.knockbacksync.KnockbackSyncBase;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
 import me.caseload.knockbacksync.player.PlatformPlayer;
-import me.caseload.knockbacksync.world.PlatformServer;
 import me.caseload.knockbacksync.stats.AdvancedPie;
 
 import java.util.HashMap;

fabric/src/main/java/me/caseload/knockbacksync/listener/fabric/FabricPlayerJoinQuitListener.java

@@ -1,7 +1,7 @@
 package me.caseload.knockbacksync.listener.fabric;
 
 import me.caseload.knockbacksync.listener.PlayerJoinQuitListener;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.player.FabricPlayer;
 import net.fabricmc.fabric.api.networking.v1.ServerPlayConnectionEvents;