Store whether a player is activ in C++

This prevents mods from mutating this value and revealing the map.

Part of this commit is written by @phosit.

binaries/data/mods/public/simulation/components/Player.js

@@ -512,6 +512,9 @@ Player.prototype.SetState = function(newState, message)
 			});
 	}
 
+	Engine.PostMessage(this.entity, won ? MT_PlayerWon : MT_PlayerDefeated,
+		{ "playerId": this.playerID });
+
 	if (message)
 		Engine.QueryInterface(SYSTEM_ENTITY, IID_GuiInterface).PushNotification({
 			"type": won ? "won" : "defeat",
@@ -519,8 +522,6 @@ Player.prototype.SetState = function(newState, message)
 			"allies": [this.playerID],
 			"message": message
 		});
-
-	Engine.PostMessage(this.entity, won ? MT_PlayerWon : MT_PlayerDefeated, { "playerId": this.playerID });
 };
 
 Player.prototype.GetFormations = function()

binaries/data/mods/public/simulation/components/interfaces/Player.js

@@ -10,18 +10,6 @@ Engine.RegisterMessageType("DisabledTechnologiesChanged");
  */
 Engine.RegisterMessageType("DisabledTemplatesChanged");
 
-/**
- * Message of the form { "playerID": number }
- * sent from Player component when a player is defeated.
- */
-Engine.RegisterMessageType("PlayerDefeated");
-
-/**
- * Message of the form { "playerID": number }
- * sent from Player component when a player has won.
- */
-Engine.RegisterMessageType("PlayerWon");
-
 /**
  * Message of the form { "to": number, "from": number, "amounts": object }
  * sent from Player component whenever a tribute is sent.

source/ps/Game.cpp

@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -486,6 +486,7 @@ bool CGame::IsGameFinished() const
 	return false;
 }
 
+// This function is implemented so that mods can't change it's result. See ICmpPlayer.cpp
 bool CGame::PlayerFinished(player_id_t playerID) const
 {
 	CmpPtr<ICmpPlayerManager> cmpPlayerManager(*m_Simulation2, SYSTEM_ENTITY);
@@ -493,5 +494,5 @@ bool CGame::PlayerFinished(player_id_t playerID) const
 		return false;
 
 	CmpPtr<ICmpPlayer> cmpPlayer(*m_Simulation2, cmpPlayerManager->GetPlayerByID(playerID));
-	return cmpPlayer && cmpPlayer->GetState() != "active";
+	return cmpPlayer && !cmpPlayer->IsActive();
 }

source/simulation2/MessageTypes.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -511,6 +511,38 @@ public:
 	player_id_t player;
 };
 
+/**
+ * Sent by the Player component when a specific player has won.
+ */
+class CMessagePlayerWon final : public CMessage
+{
+public:
+	DEFAULT_MESSAGE_IMPL(PlayerWon)
+
+	CMessagePlayerWon(player_id_t playerId) :
+		playerId{playerId}
+	{
+	}
+
+	player_id_t playerId;
+};
+
+/**
+ * Sent by the Player component when an specific player has been defeated.
+ */
+class CMessagePlayerDefeated final : public CMessage
+{
+public:
+	DEFAULT_MESSAGE_IMPL(PlayerDefeated)
+
+	CMessagePlayerDefeated(player_id_t playerId) :
+		playerId{playerId}
+	{
+	}
+
+	player_id_t playerId;
+};
+
 /**
  * Sent by aura and tech managers when a value of a certain template's component is changed
  */

source/simulation2/TypeList.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -61,6 +61,8 @@ MESSAGE(MinimapPing)
 MESSAGE(CinemaPathEnded)
 MESSAGE(CinemaQueueEnded)
 MESSAGE(PlayerColorChanged)
+MESSAGE(PlayerWon)
+MESSAGE(PlayerDefeated)
 
 // TemplateManager must come before all other (non-test) components,
 // so that it is the first to be (de)serialized

source/simulation2/components/ICmpPlayer.cpp

@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -21,6 +21,7 @@
 
 #include "graphics/Color.h"
 #include "maths/FixedVector3D.h"
+#include "simulation2/system/Component.h"
 #include "simulation2/system/InterfaceScripted.h"
 #include "simulation2/scripting/ScriptComponent.h"
 
@@ -30,7 +31,41 @@ END_INTERFACE_WRAPPER(Player)
 class CCmpPlayerScripted : public ICmpPlayer
 {
 public:
-	DEFAULT_SCRIPT_WRAPPER(PlayerScripted)
+	DEFAULT_SCRIPT_WRAPPER_BASIC(PlayerScripted)
+
+	static void ClassInit(CComponentManager& componentManager)
+	{
+		componentManager.SubscribeToMessageType(MT_PlayerWon);
+		componentManager.SubscribeToMessageType(MT_PlayerDefeated);
+	}
+
+	void Serialize(ISerializer& serialize) final
+	{
+		serialize.Bool("isActive", m_IsActive);
+		m_Script.Serialize(serialize);
+	}
+
+	void Deserialize(const CParamNode& paramNode, IDeserializer& deserialize) final
+	{
+		deserialize.Bool("isActive", m_IsActive);
+		m_Script.Deserialize(paramNode, deserialize, GetEntityId());
+	}
+
+	void HandleMessage(const CMessage& msg, bool global) final
+	{
+		const int msgType{msg.GetType()};
+
+		// Handle messages that were subscribed to in ClassInit.
+		if (msgType == MT_PlayerWon || msgType == MT_PlayerDefeated)
+		{
+			m_IsActive = false;
+			if (!m_Script.HasMessageHandler(msg, global))
+				return;
+		}
+
+		// Handle messages that were subscribed to within the JS implementation of the interface.
+		m_Script.HandleMessage(msg, global);
+	}
 
 	CColor GetDisplayedColor() override
 	{
@@ -56,6 +91,18 @@ public:
 	{
 		return m_Script.Call<std::string>("GetState");
 	}
+
+	bool IsActive() final
+	{
+		return m_IsActive;
+	}
+
+private:
+	// Serialize this player state variable in C++ so that mods can't manipulate this value in order to
+	// reveal the map locally.
+	// Once it's set to `false` it's never set to true again. To prevent mods from temporarily changing
+	// it.
+	bool m_IsActive{true};
 };
 
 REGISTER_COMPONENT_SCRIPT_WRAPPER(PlayerScripted)

source/simulation2/components/ICmpPlayer.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -39,6 +39,9 @@ public:
 	virtual bool HasStartingCamera() = 0;
 	virtual std::string GetState() = 0;
 
+	// See the cpp file for why this is implemented in C++.
+	virtual bool IsActive() = 0;
+
 	DECLARE_INTERFACE_TYPE(Player)
 };
 

source/simulation2/scripting/MessageTypeConversions.cpp

@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -541,6 +541,38 @@ CMessage* CMessagePlayerColorChanged::FromJSVal(const ScriptRequest& rq, JS::Han
 	return new CMessagePlayerColorChanged(player);
 }
 
+////////////////////////////////
+
+JS::Value CMessagePlayerWon::ToJSVal(const ScriptRequest& rq) const
+{
+	TOJSVAL_SETUP();
+	SET_MSG_PROPERTY(playerId);
+	return JS::ObjectValue(*obj);
+}
+
+CMessage* CMessagePlayerWon::FromJSVal(const ScriptRequest& rq, JS::HandleValue val)
+{
+	FROMJSVAL_SETUP();
+	GET_MSG_PROPERTY(player_id_t, playerId);
+	return new CMessagePlayerWon(playerId);
+}
+
+////////////////////////////////
+
+JS::Value CMessagePlayerDefeated::ToJSVal(const ScriptRequest& rq) const
+{
+	TOJSVAL_SETUP();
+	SET_MSG_PROPERTY(playerId);
+	return JS::ObjectValue(*obj);
+}
+
+CMessage* CMessagePlayerDefeated::FromJSVal(const ScriptRequest& rq, JS::HandleValue val)
+{
+	FROMJSVAL_SETUP();
+	GET_MSG_PROPERTY(player_id_t, playerId);
+	return new CMessagePlayerDefeated(playerId);
+}
+
 ////////////////////////////////////////////////////////////////
 
 CMessage* CMessageFromJSVal(int mtid, const ScriptRequest& rq, JS::HandleValue val)

source/simulation2/scripting/ScriptComponent.cpp

@@ -1,4 +1,4 @@
-/* Copyright (C) 2023 Wildfire Games.
+/* Copyright (C) 2024 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -46,6 +46,13 @@ void CComponentTypeScript::Deinit()
 	ScriptFunction::CallVoid(rq, m_Instance, "Deinit");
 }
 
+bool CComponentTypeScript::HasMessageHandler(const CMessage& msg, const bool global)
+{
+	const ScriptRequest rq(m_ScriptInterface);
+	return Script::HasProperty(rq, m_Instance, global ? msg.GetScriptGlobalHandlerName() :
+		msg.GetScriptHandlerName());
+}
+
 void CComponentTypeScript::HandleMessage(const CMessage& msg, bool global)
 {
 	ScriptRequest rq(m_ScriptInterface);

source/simulation2/scripting/ScriptComponent.h

@@ -41,6 +41,7 @@ public:
 
 	void Init(const CParamNode& paramNode, entity_id_t ent);
 	void Deinit();
+	bool HasMessageHandler(const CMessage& msg, const bool global);
 	void HandleMessage(const CMessage& msg, bool global);
 
 	void Serialize(ISerializer& serialize);
@@ -88,8 +89,7 @@ private:
 	}
 
 
-#define DEFAULT_SCRIPT_WRAPPER(cname) \
-	static void ClassInit(CComponentManager& UNUSED(componentManager)) { } \
+#define DEFAULT_SCRIPT_WRAPPER_BASIC(cname) \
 	static IComponent* Allocate(const ScriptInterface& scriptInterface, JS::HandleValue instance) \
 	{ \
 		return new CCmp##cname(scriptInterface, instance); \
@@ -111,18 +111,6 @@ private:
 	{ \
 		m_Script.Deinit(); \
 	} \
-	void HandleMessage(const CMessage& msg, bool global) override \
-	{ \
-		m_Script.HandleMessage(msg, global); \
-	} \
-	void Serialize(ISerializer& serialize) override \
-	{ \
-		m_Script.Serialize(serialize); \
-	} \
-	void Deserialize(const CParamNode& paramNode, IDeserializer& deserialize) override \
-	{ \
-		m_Script.Deserialize(paramNode, deserialize, GetEntityId()); \
-	} \
 	JS::Value GetJSInstance() const override \
 	{ \
 		return m_Script.GetInstance(); \
@@ -135,4 +123,21 @@ private:
 		CComponentTypeScript m_Script; \
 	public:
 
+
+#define DEFAULT_SCRIPT_WRAPPER(cname) \
+	static void ClassInit(CComponentManager& UNUSED(componentManager)) { } \
+	void HandleMessage(const CMessage& msg, bool global) override \
+	{ \
+		m_Script.HandleMessage(msg, global); \
+	} \
+	void Serialize(ISerializer& serialize) override \
+	{ \
+		m_Script.Serialize(serialize); \
+	} \
+	void Deserialize(const CParamNode& paramNode, IDeserializer& deserialize) override \
+	{ \
+		m_Script.Deserialize(paramNode, deserialize, GetEntityId()); \
+	} \
+	DEFAULT_SCRIPT_WRAPPER_BASIC(cname)
+
 #endif // INCLUDED_SCRIPTCOMPONENT

source/simulation2/system/ComponentManager.cpp

@@ -20,6 +20,7 @@
 #include "ComponentManager.h"
 
 #include "lib/utf8.h"
+#include "ps/algorithm.h"
 #include "ps/CLogger.h"
 #include "ps/Filesystem.h"
 #include "ps/Profile.h"
@@ -303,10 +304,17 @@ void CComponentManager::Script_RegisterComponentType_Common(int iid, const std::
 			return;
 		}
 
+		// If we have already subscribed in classInit, do not subscribe again
 		if (isGlobal)
-			SubscribeGloballyToMessageType(mit->second);
+		{
+			if (!IsGloballySubscribed(mit->second))
+				SubscribeGloballyToMessageType(mit->second);
+		}
 		else
-			SubscribeToMessageType(mit->second);
+		{
+			if (!IsLocallySubscribed(mit->second))
+				SubscribeToMessageType(mit->second);
+		}
 	}
 
 	m_CurrentComponent = CID__Invalid;
@@ -571,6 +579,18 @@ void CComponentManager::SubscribeGloballyToMessageType(MessageTypeId mtid)
 	std::sort(types.begin(), types.end()); // TODO: just sort once at the end of LoadComponents
 }
 
+bool CComponentManager::IsLocallySubscribed(MessageTypeId mtid)
+{
+	ENSURE(m_CurrentComponent != CID__Invalid);
+	return PS::contains(m_LocalMessageSubscriptions[mtid], m_CurrentComponent);
+}
+
+bool CComponentManager::IsGloballySubscribed(MessageTypeId mtid)
+{
+	ENSURE(m_CurrentComponent != CID__Invalid);
+	return PS::contains(m_GlobalMessageSubscriptions[mtid], m_CurrentComponent);
+}
+
 void CComponentManager::FlattenDynamicSubscriptions()
 {
 	std::map<MessageTypeId, CDynamicSubscription>::iterator it;

source/simulation2/system/ComponentManager.h

@@ -113,6 +113,16 @@ public:
 	 */
 	void SubscribeGloballyToMessageType(MessageTypeId mtid);
 
+	/**
+	 * Check if the current component type is subscribed to messages of the given type.
+	 */
+	bool IsLocallySubscribed(MessageTypeId mtid);
+
+	/**
+	 * Check if the current component type is globally subscribed to messages of the given type.
+	 */
+	bool IsGloballySubscribed(MessageTypeId mtid);
+
 	/**
 	 * Subscribe the given component instance to all messages of the given message type.
 	 * The component's HandleMessage will be called on any BroadcastMessage or PostMessage of