Move state frequency to ServerConfig which clients can adapt

src/network/network_config.cpp

@@ -57,6 +57,7 @@ NetworkConfig::NetworkConfig()
         0 : stk_config->m_client_port;
     m_joined_server_version = 0;
     m_network_ai_tester = false;
+    m_state_frequency = 10;
 }   // NetworkConfig
 
 // ----------------------------------------------------------------------------

src/network/network_config.hpp

@@ -90,6 +90,9 @@ private:
 
     uint32_t m_joined_server_version;
 
+    /** Set by client or server which is required to be the same. */
+    int m_state_frequency;
+
 public:
     /** Singleton get, which creates this object if necessary. */
     static NetworkConfig *get()
@@ -222,6 +225,10 @@ public:
     uint32_t getJoinedServerVersion() const { return m_joined_server_version; }
     // ------------------------------------------------------------------------
     void clearActivePlayersForClient() const;
+    // ------------------------------------------------------------------------
+    void setStateFrequency(int frequency)    { m_state_frequency = frequency; }
+    // ------------------------------------------------------------------------
+    int getStateFrequency() const                 { return m_state_frequency; }
 };   // class NetworkConfig
 
 #endif // HEADER_NETWORK_CONFIG

src/network/protocols/client_lobby.cpp

@@ -268,7 +268,6 @@ void ClientLobby::addAllPlayers(Event* event)
         float time_limit = data.getFloat();
         m_game_setup->setHitCaptureTime(hit_capture_limit, time_limit);
     }
-
     configRemoteKart(players);
     loadWorld();
     // Disable until render gui during loading is bug free
@@ -523,6 +522,8 @@ void ClientLobby::connectionAccepted(Event* event)
     m_auto_started = false;
     m_state.store(CONNECTED);
     float auto_start_timer = data.getFloat();
+    int state_frequency_in_server = data.getUInt32();
+    NetworkConfig::get()->setStateFrequency(state_frequency_in_server);
     if (auto_start_timer != std::numeric_limits<float>::max())
         NetworkingLobby::getInstance()->setStartingTimerTo(auto_start_timer);
 }   // connectionAccepted

src/network/protocols/server_lobby.cpp

@@ -1812,7 +1812,8 @@ void ServerLobby::handleUnencryptedConnection(std::shared_ptr<STKPeer> peer,
             (m_timeout.load() - (int64_t)StkTime::getRealTimeMs()) / 1000.0f;
     }
     message_ack->addUInt8(LE_CONNECTION_ACCEPTED).addUInt32(peer->getHostId())
-        .addUInt32(ServerConfig::m_server_version).addFloat(auto_start_timer);
+        .addUInt32(ServerConfig::m_server_version).addFloat(auto_start_timer)
+        .addUInt32(ServerConfig::m_state_frequency);
 
     if (game_started)
     {

src/network/rewind_manager.cpp

@@ -80,8 +80,8 @@ void RewindManager::reset()
     m_not_rewound_ticks.store(0);
     m_overall_state_size = 0;
     m_last_saved_state = -1;  // forces initial state save
-    m_state_frequency =
-        stk_config->getPhysicsFPS() / stk_config->m_network_state_frequeny;
+    m_state_frequency = stk_config->getPhysicsFPS() /
+        NetworkConfig::get()->getStateFrequency();
 
     if (!m_enable_rewind_manager) return;
 

src/network/server_config.cpp

@@ -34,6 +34,7 @@ static std::vector<UserConfigParam*> g_server_params;
 #include "config/stk_config.hpp"
 #include "io/file_manager.hpp"
 #include "network/game_setup.hpp"
+#include "network/network_config.hpp"
 #include "network/protocols/lobby_protocol.hpp"
 #include "network/stk_host.hpp"
 #include "race/race_manager.hpp"
@@ -256,6 +257,16 @@ void loadServerLobbyFromConfig()
     if (unsupportedGameMode())
         Log::fatal("ServerConfig", "Unsupported game mode");
 
+    int frequency_in_config = m_state_frequency;
+    if (frequency_in_config > stk_config->getPhysicsFPS())
+    {
+        Log::warn("ServerConfig", "Invalid %d state frequency which is larger "
+            "than physics FPS %d, use default value.",
+            frequency_in_config, stk_config->getPhysicsFPS());
+        m_state_frequency.revertToDefaults();
+    }
+    NetworkConfig::get()->setStateFrequency(m_state_frequency);
+
     if (m_server_difficulty > RaceManager::DIFFICULTY_LAST)
         m_server_difficulty = RaceManager::DIFFICULTY_LAST;
     if (m_server_mode > 8)

src/network/server_config.hpp

@@ -295,6 +295,14 @@ namespace ServerConfig
         "Negative value to disable, and this option will always be disabled "
         "for LAN server."));
 
+    SERVER_CFG_PREFIX IntServerConfigParam m_state_frequency
+        SERVER_CFG_DEFAULT(IntServerConfigParam(10,
+        "state-frequency",
+        "Set how many states the server will send per second, the higher this "
+        "value, the more bandwidth requires, also each client will trigger "
+        "more rewind, which clients with slow device may have problem playing "
+        "this server, use the default value is recommended."));
+
     SERVER_CFG_PREFIX StringToUIntServerConfigParam m_server_ip_ban_list
         SERVER_CFG_DEFAULT(StringToUIntServerConfigParam("server-ip-ban-list",
         "ip: IP in X.X.X.X/Y (CIDR) format for banning, use Y of 32 for a "