Latejoin traitors (#9783)

Content.Server/GameTicking/GameTicker.RoundFlow.cs

@@ -357,6 +357,8 @@ namespace Content.Server.GameTicking
 
             RoundNumberMetric.Inc();
 
+            PlayersJoinedRoundNormally = 0;
+
             RunLevel = GameRunLevel.PreRoundLobby;
             LobbySong = _robustRandom.Pick(_lobbyMusicCollection.PickFiles).ToString();
             RandomizeLobbyBackground();

Content.Server/GameTicking/GameTicker.Spawning.cs

@@ -28,6 +28,12 @@ namespace Content.Server.GameTicking
         [ViewVariables(VVAccess.ReadWrite), Obsolete("Due for removal when observer spawning is refactored.")]
         private EntityCoordinates _spawnPoint;
 
+        /// <summary>
+        /// How many players have joined the round through normal methods.
+        /// Useful for game rules to look at. Doesn't count observers, people in lobby, etc.
+        /// </summary>
+        public int PlayersJoinedRoundNormally = 0;
+
         // Mainly to avoid allocations.
         private readonly List<EntityCoordinates> _possiblePositions = new();
 
@@ -193,7 +199,8 @@ namespace Content.Server.GameTicking
             }
 
             // We raise this event directed to the mob, but also broadcast it so game rules can do something now.
-            var aev = new PlayerSpawnCompleteEvent(mob, player, jobId, lateJoin, station, character);
+            PlayersJoinedRoundNormally++;
+            var aev = new PlayerSpawnCompleteEvent(mob, player, jobId, lateJoin, PlayersJoinedRoundNormally, station, character);
             RaiseLocalEvent(mob, aev, true);
         }
 
@@ -317,7 +324,10 @@ namespace Content.Server.GameTicking
         public EntityUid Station { get; }
         public HumanoidCharacterProfile Profile { get; }
 
-        public PlayerSpawnCompleteEvent(EntityUid mob, IPlayerSession player, string? jobId, bool lateJoin, EntityUid station, HumanoidCharacterProfile profile)
+        // Ex. If this is the 27th person to join, this will be 27.
+        public int JoinOrder { get; }
+
+        public PlayerSpawnCompleteEvent(EntityUid mob, IPlayerSession player, string? jobId, bool lateJoin, int joinOrder, EntityUid station, HumanoidCharacterProfile profile)
         {
             Mob = mob;
             Player = player;
@@ -325,6 +335,7 @@ namespace Content.Server.GameTicking
             LateJoin = lateJoin;
             Station = station;
             Profile = profile;
+            JoinOrder = joinOrder;
         }
     }
 }

Content.Server/GameTicking/Rules/TraitorRuleSystem.cs

@@ -1,7 +1,5 @@
-using System.Collections.Generic;
 using System.Linq;
 using Content.Server.Chat.Managers;
-using Content.Server.GameTicking.Rules.Configurations;
 using Content.Server.Objectives.Interfaces;
 using Content.Server.Players;
 using Content.Server.Roles;
@@ -42,12 +40,16 @@ public sealed class TraitorRuleSystem : GameRuleSystem
     public int TotalTraitors => Traitors.Count;
     public string[] Codewords = new string[3];
 
+    private int _playersPerTraitor => _cfg.GetCVar(CCVars.TraitorPlayersPerTraitor);
+    private int _maxTraitors => _cfg.GetCVar(CCVars.TraitorMaxTraitors);
+
     public override void Initialize()
     {
         base.Initialize();
 
         SubscribeLocalEvent<RoundStartAttemptEvent>(OnStartAttempt);
         SubscribeLocalEvent<RulePlayerJobsAssignedEvent>(OnPlayersSpawned);
+        SubscribeLocalEvent<PlayerSpawnCompleteEvent>(HandleLatejoin);
         SubscribeLocalEvent<RoundEndTextAppendEvent>(OnRoundEndText);
     }
 
@@ -107,9 +109,8 @@ public sealed class TraitorRuleSystem : GameRuleSystem
         if (!RuleAdded)
             return;
 
-        var playersPerTraitor = _cfg.GetCVar(CCVars.TraitorPlayersPerTraitor);
+        var numTraitors = MathHelper.Clamp(ev.Players.Length / _playersPerTraitor, 1, _maxTraitors);
-        var maxTraitors = _cfg.GetCVar(CCVars.TraitorMaxTraitors);
+        var codewordCount = _cfg.GetCVar(CCVars.TraitorCodewordCount);
-        var numTraitors = MathHelper.Clamp(ev.Players.Length / playersPerTraitor, 1, maxTraitors);
 
         var traitorPool = FindPotentialTraitors(ev);
         var selectedTraitors = PickTraitors(numTraitors, traitorPool);
@@ -154,7 +155,7 @@ public sealed class TraitorRuleSystem : GameRuleSystem
             Logger.InfoS("preset", "Insufficient ready players to fill up with traitors, stopping the selection.");
             return results;
         }
-        
+
         for (var i = 0; i < traitorCount; i++)
         {
             results.Add(_random.PickAndTake(prefList));
@@ -211,6 +212,48 @@ public sealed class TraitorRuleSystem : GameRuleSystem
         return true;
     }
 
+    private void HandleLatejoin(PlayerSpawnCompleteEvent ev)
+    {
+        if (!RuleAdded)
+            return;
+        if (TotalTraitors >= _maxTraitors)
+            return;
+        if (!ev.LateJoin)
+            return;
+        if (!ev.Profile.AntagPreferences.Contains(TraitorPrototypeID))
+            return;
+
+
+        if (ev.JobId == null || !_prototypeManager.TryIndex<JobPrototype>(ev.JobId, out var job))
+            return;
+
+        if (!job.CanBeAntag)
+            return;
+
+        // the nth player we adjust our probabilities around
+        int target = ((_playersPerTraitor * TotalTraitors) + 1);
+
+        float chance = (1f / _playersPerTraitor);
+
+        /// If we have too many traitors, divide by how many players below target for next traitor we are.
+        if (ev.JoinOrder < target)
+        {
+            chance /= (target - ev.JoinOrder);
+        } else // Tick up towards 100% chance.
+        {
+            chance *= ((ev.JoinOrder + 1) - target);
+        }
+        if (chance > 1)
+            chance = 1;
+
+        // Now that we've calculated our chance, roll and make them a traitor if we roll under.
+        // You get one shot.
+        if (_random.Prob((float) chance))
+        {
+            MakeTraitor(ev.Player);
+        }
+    }
+
     private void OnRoundEndText(RoundEndTextAppendEvent ev)
     {
         if (!RuleAdded)

Content.Server/Objectives/Conditions/KillPersonCondition.cs

@@ -29,7 +29,7 @@ namespace Content.Server.Objectives.Conditions
 
         public string Description => Loc.GetString("objective-condition-kill-person-description");
 
-        public SpriteSpecifier Icon => new SpriteSpecifier.Rsi(new ResourcePath("Objects/Weapons/Guns/Pistols/mk58_wood.rsi"), "icon");
+        public SpriteSpecifier Icon => new SpriteSpecifier.Rsi(new ResourcePath("Objects/Weapons/Guns/Pistols/viper.rsi"), "icon");
 
         public float Progress => (Target?.CharacterDeadIC ?? true) ? 1f : 0f;
 

Content.Shared/CCVar/CCVars.cs

@@ -246,7 +246,7 @@ namespace Content.Shared.CCVar
             CVarDef.Create("suspicion.min_traitors", 2);
 
         public static readonly CVarDef<int> SuspicionPlayersPerTraitor =
-            CVarDef.Create("suspicion.players_per_traitor", 5);
+            CVarDef.Create("suspicion.players_per_traitor", 6);
 
         public static readonly CVarDef<int> SuspicionStartingBalance =
             CVarDef.Create("suspicion.starting_balance", 20);
@@ -262,7 +262,7 @@ namespace Content.Shared.CCVar
             CVarDef.Create("traitor.min_players", 5);
 
         public static readonly CVarDef<int> TraitorMaxTraitors =
-            CVarDef.Create("traitor.max_traitors", 7);
+            CVarDef.Create("traitor.max_traitors", 12); // Assuming average server maxes somewhere from like 50-80 people
 
         public static readonly CVarDef<int> TraitorPlayersPerTraitor =
             CVarDef.Create("traitor.players_per_traitor", 5);