Replace cheat-detection teleport with server reconciliation

The old PUNKBUSTER check compared client-reported position to server
position and snapped the player back when latency made them diverge,
which felt like getting teleported under any real network conditions.

Replaces that with proper client-side prediction + reconciliation:
client tags each input with a sequence number and keeps an input
buffer; server tracks the last processed sequence and reports its
authoritative position via a per-user inputAck alongside each
worldUpdate. The client only corrects when the actual disagreement
exceeds what the unacked input time can explain — so steady-state
movement runs purely on local physics, and only genuine unexpected
events (collisions, being hit) trigger a smooth blend toward the
server state.

Includes adaptive threshold scaling so high-latency sessions don't
false-positive corrections during normal running.

app/Game/Channel/Control/PlayerController.js

@@ -1,24 +1,24 @@
 define([
 	"Game/Core/Control/PlayerController",
 	"Lib/Utilities/NotificationCenter",
-    "Lib/Utilities/Protocol/Parser",
-    "Game/Config/Settings"
+    "Lib/Utilities/Protocol/Parser"
 ],
- 
-function(Parent, nc, Parser, Settings) {
+
+function(Parent, nc, Parser) {
 
     "use strict";
  
     function PlayerController(player) {
 
     	Parent.call(this, player);
+        this._lastProcessedSeq = 0;
     }
 
     PlayerController.prototype = Object.create(Parent.prototype);
 
-    /* 
-     * retrieves move (and other) commands from client and executes them at the server 
-     */ 
+    /*
+     * retrieves move (and other) commands from client and executes them at the server
+     */
     PlayerController.prototype.applyCommand = function(options) {
         // FIXME: remove this function and use ProtocolHelper.applyCommand() instead
         // Don't forget to change the function names to on...
@@ -28,9 +28,16 @@ function(Parent, nc, Parser, Settings) {
         } else {
             message = options;
         }
-        
+
         for (var command in message) {
-            this[command].call(this, message[command]);
+            var commandOptions = message[command];
+
+            // Track sequence number from client input commands
+            if (commandOptions && typeof commandOptions === 'object' && commandOptions._seq !== undefined) {
+                this._lastProcessedSeq = commandOptions._seq;
+            }
+
+            this[command].call(this, commandOptions);
         }
     };
 
@@ -45,36 +52,6 @@ function(Parent, nc, Parser, Settings) {
         this.player.suicide();
     };
 
-    PlayerController.prototype.mePositionStateOverride = function(update) {
-
-        if(!this.player.isSpawned()) {
-            // if someone still falls but is dead on the server already
-            return; 
-        }
-
-        var difference = {
-            x: Math.abs(update.p.x - this.player.doll.body.GetPosition().x),
-            y: Math.abs(update.p.y - this.player.doll.body.GetPosition().y)
-        };
-
-        if(difference.x < Settings.PUNKBUSTER_DIFFERENCE_METERS &&
-           difference.y < Settings.PUNKBUSTER_DIFFERENCE_METERS) {
-            this.player.doll.updatePositionState(update);
-        } else {
-            // HARD UPDATE FOR SELF
-            console.log(this.player.user.options.nickname + " is cheating.");
-
-            var body = this.player.doll.body;
-
-            var options = {
-                p: body.GetPosition(),
-                lv: body.GetLinearVelocity()
-            };
-
-            nc.trigger(nc.ns.channel.to.client.user.gameCommand.send + this.player.id, "positionStateReset", options);
-        }
-    };
-
     return PlayerController;
  
 });

app/Game/Channel/GameController.js

@@ -113,13 +113,30 @@ function (Parent, PhysicsEngine, Settings, requestAnimFrame, nc, Box2D, Player,
     };
 
     GameController.prototype.updateWorld = function () {
-        
+
         var update = this.getWorldUpdateObject(false);
 
         if(Object.getOwnPropertyNames(update).length > 0) {
             nc.trigger(nc.ns.channel.to.client.gameCommand.broadcast, "worldUpdate", update);
         }
 
+        // Send per-user input acknowledgments for server reconciliation
+        for (var id in this.players) {
+            var player = this.players[id];
+            if (player.isSpawned() && player.playerController._lastProcessedSeq > 0) {
+                var body = player.doll.body;
+                nc.trigger(
+                    nc.ns.channel.to.client.user.gameCommand.send + id,
+                    "inputAck",
+                    {
+                        seq: player.playerController._lastProcessedSeq,
+                        p: { x: body.GetPosition().x, y: body.GetPosition().y },
+                        lv: { x: body.GetLinearVelocity().x, y: body.GetLinearVelocity().y }
+                    }
+                );
+            }
+        }
+
         this.worldUpdateTimeout = setTimeout(this.updateWorld.bind(this), Settings.NETWORK_UPDATE_INTERVAL);
     };
 

app/Game/Channel/GameObjects/Doll.js

@@ -2,11 +2,10 @@ define([
 	"Game/Core/GameObjects/Doll",
     "Game/Channel/GameObjects/Item",
     "Lib/Vendor/Box2D",
-    "Lib/Utilities/NotificationCenter",
-    "Lib/Utilities/Assert"
+    "Lib/Utilities/NotificationCenter"
 ],
- 
-function (Parent, Item, Box2D, nc, Assert) {
+
+function (Parent, Item, Box2D, nc) {
 
 	"use strict";
  
@@ -93,16 +92,6 @@ function (Parent, Item, Box2D, nc, Assert) {
         }
     };
 
-    Doll.prototype.updatePositionState = function(update) {
-        if(!this.isAnotherPlayerNearby()) {
-            Assert.number(update.p.x, update.p.y);
-            Assert.number(update.lv.x, update.lv.y);
-            this.body.SetAwake(true);
-            this.body.SetPosition(update.p);
-            this.body.SetLinearVelocity(update.lv);
-        }
-    };
-
     Doll.prototype.getUpdateData = function(getSleeping) {
 
         var updateData = Parent.prototype.getUpdateData.call(this, getSleeping);