Add live join and spectate button to lobby

src/modes/world.cpp

@@ -253,12 +253,15 @@ void World::init()
 
     if (Camera::getNumCameras() == 0)
     {
+        auto cl = LobbyProtocol::get<ClientLobby>();
         if ( (NetworkConfig::get()->isServer() && 
               !ProfileWorld::isNoGraphics()       ) ||
-            race_manager->isWatchingReplay()            )
+            race_manager->isWatchingReplay()        ||
+            (cl && cl->isSpectator()))
         {
-            // In case that the server is running with gui or watching replay,
+            // In case that the server is running with gui, watching replay or
-            // create a camera and attach it to the first kart.
+            // spectating the game, create a camera and attach it to the first
+            // kart.
             Camera::createCamera(World::getWorld()->getKart(0), 0);
 
         }   // if server with graphics of is watching replay

src/network/game_setup.cpp

@@ -155,6 +155,7 @@ void GameSetup::addServerInfo(NetworkString* ns)
 
     ns->encodeString16(m_message_of_today);
     ns->addUInt8((uint8_t)ServerConfig::m_server_configurable);
+    ns->addUInt8(race_manager->supportsLiveJoining() ? 1 : 0);
 }   // addServerInfo
 
 //-----------------------------------------------------------------------------

src/network/protocols/client_lobby.cpp

@@ -29,6 +29,7 @@
 #include "items/powerup_manager.hpp"
 #include "karts/abstract_kart.hpp"
 #include "karts/controller/controller.hpp"
+#include "karts/kart_properties.hpp"
 #include "karts/kart_properties_manager.hpp"
 #include "modes/linear_world.hpp"
 #include "network/crypto.hpp"
@@ -91,6 +92,7 @@ ClientLobby::ClientLobby(const TransportAddress& a, std::shared_ptr<Server> s)
     m_disconnected_msg[PDI_BAD_CONNECTION] =
         _("Bad network connection is detected.");
     m_first_connect = true;
+    m_spectator = false;
 }   // ClientLobby
 
 //-----------------------------------------------------------------------------
@@ -110,6 +112,7 @@ ClientLobby::~ClientLobby()
 //-----------------------------------------------------------------------------
 void ClientLobby::setup()
 {
+    m_spectator = false;
     m_auto_back_to_lobby_time = std::numeric_limits<uint64_t>::max();
     m_start_live_game_time = std::numeric_limits<uint64_t>::max();
     m_received_server_result = false;
@@ -649,6 +652,9 @@ void ClientLobby::handleServerInfo(Event* event)
     }
     bool server_config = data.getUInt8() == 1;
     NetworkingLobby::getInstance()->toggleServerConfigButton(server_config);
+    bool live_join_spectator = data.getUInt8() == 1;
+    NetworkingLobby::getInstance()
+        ->toggleServerLiveJoinable(live_join_spectator);
 }   // handleServerInfo
 
 //-----------------------------------------------------------------------------
@@ -1101,3 +1107,21 @@ void ClientLobby::handleKartInfo(Event* event)
     SFXManager::get()->quickSound("energy_bar_full");
     MessageQueue::add(MessageQueue::MT_FRIEND, msg);
 }   // handleKartInfo
+
+//-----------------------------------------------------------------------------
+void ClientLobby::startLiveJoinKartSelection()
+{
+    NetworkKartSelectionScreen::getInstance()->setLiveJoin(true);
+    std::vector<int> all_k =
+        kart_properties_manager->getKartsInGroup("standard");
+    std::set<std::string> karts;
+    for (int kart : all_k)
+    {
+        const KartProperties* kp = kart_properties_manager->getKartById(kart);
+        if (!kp->isAddon())
+            karts.insert(kp->getIdent());
+    }
+    NetworkKartSelectionScreen::getInstance()
+        ->setAvailableKartsFromServer(karts);
+    NetworkKartSelectionScreen::getInstance()->push();
+}   // startLiveJoinKartSelection

src/network/protocols/client_lobby.hpp

@@ -79,6 +79,8 @@ private:
 
     bool m_first_connect;
 
+    bool m_spectator;
+
     uint64_t m_auto_back_to_lobby_time;
 
     uint64_t m_start_live_game_time;
@@ -125,6 +127,9 @@ public:
     bool isServerAutoGameTime() const       { return m_server_auto_game_time; }
     virtual bool isRacing() const OVERRIDE { return m_state.load() == RACING; }
     void requestKartInfo(uint8_t kart_id);
+    void setSpectator(bool val)                          { m_spectator = val; }
+    bool isSpectator() const                            { return m_spectator; }
+    void startLiveJoinKartSelection();
 };
 
 #endif // CLIENT_LOBBY_HPP

src/network/protocols/game_protocol.cpp

@@ -174,7 +174,8 @@ void GameProtocol::controllerAction(int kart_id, PlayerAction action,
 void GameProtocol::handleControllerAction(Event *event)
 {
     STKPeer* peer = event->getPeer();
-    if (NetworkConfig::get()->isServer() && peer->isWaitingForGame())
+    if (NetworkConfig::get()->isServer() && (peer->isWaitingForGame() ||
+        peer->getAvailableKartIDs().empty()))
         return;
     NetworkString &data = event->data();
     uint8_t count = data.getUInt8();

src/network/protocols/server_lobby.cpp

@@ -696,6 +696,9 @@ void ServerLobby::liveJoinRequest(Event* event)
         rejectLiveJoin(peer, BLR_NO_GAME_FOR_LIVE_JOIN);
         return;
     }
+    bool spectator = data.getUInt8() == 1;
+    if (!spectator)
+    {
         setPlayerKarts(data, peer);
 
         std::vector<int> used_id;
@@ -728,6 +731,13 @@ void ServerLobby::liveJoinRequest(Event* event)
                 peer->getAddress().toString().c_str(), id);
             peer->addAvailableKartID(id);
         }
+    }
+    else
+    {
+        Log::info("ServerLobby", "%s spectating now.",
+            peer->getAddress().toString().c_str());
+    }
+
     std::vector<std::shared_ptr<NetworkPlayerProfile> > players;
     for (unsigned i = 0; i < race_manager->getNumPlayers(); i++)
     {
@@ -856,9 +866,14 @@ void ServerLobby::finishedLoadingLiveJoinClient(Event* event)
         World::getWorld()->addReservedKart(id);
         const RemoteKartInfo& rki = race_manager->getKartInfo(id);
         addLiveJoiningKart(id, rki, m_last_live_join_util_ticks);
+        Log::info("ServerLobby", "%s live-joining succeeded with kart id %d.",
+            peer->getAddress().toString().c_str(), id);
     }
-    Log::info("ServerLobby", "%s live-joining succeeded.",
+    if (peer->getAvailableKartIDs().empty())
+    {
+        Log::info("ServerLobby", "%s spectating succeeded.",
             peer->getAddress().toString().c_str());
+    }
 
     NetworkString* ns = getNetworkString(10);
     ns->setSynchronous(true);

src/states_screens/online/network_kart_selection.cpp

@@ -104,7 +104,9 @@ void NetworkKartSelectionScreen::allPlayersDone()
     if (m_live_join)
     {
         kart.setSynchronous(true);
-        kart.addUInt8(LobbyProtocol::LE_LIVE_JOIN);
+        kart.addUInt8(LobbyProtocol::LE_LIVE_JOIN)
+            // not spectator
+            .addUInt8(0);
     }
     else
         kart.addUInt8(LobbyProtocol::LE_KART_SELECTION);

src/states_screens/online/networking_lobby.cpp

@@ -41,6 +41,7 @@
 #include "network/protocols/client_lobby.hpp"
 #include "network/server.hpp"
 #include "network/stk_host.hpp"
+#include "network/network_timer_synchronizer.hpp"
 #include "states_screens/dialogs/splitscreen_player_dialog.hpp"
 #include "states_screens/dialogs/network_user_dialog.hpp"
 #include "states_screens/dialogs/server_configuration_dialog.hpp"
@@ -122,6 +123,10 @@ void NetworkingLobby::loadedFromFile()
         (file_manager->getAsset(FileManager::GUI_ICON, "hourglass.png"));
     video::ITexture* icon_5 = irr_driver->getTexture
         (file_manager->getAsset(FileManager::GUI_ICON, "green_check.png"));
+    m_config_texture = irr_driver->getTexture
+        (file_manager->getAsset(FileManager::GUI_ICON, "main_options.png"));
+    m_spectate_texture = irr_driver->getTexture
+        (file_manager->getAsset(FileManager::GUI_ICON, "screen_other.png"));
     m_icon_bank->addTextureAsSprite(icon_1);
     m_icon_bank->addTextureAsSprite(icon_2);
     m_icon_bank->addTextureAsSprite(icon_3);
@@ -161,6 +166,8 @@ void NetworkingLobby::init()
     m_player_names.clear();
     m_allow_change_team = false;
     m_has_auto_start_in_server = false;
+    m_server_live_joinable = false;
+    m_client_live_joinable = false;
     m_ping_update_timer = 0.0f;
     m_start_timeout = std::numeric_limits<float>::max();
     m_cur_starting_timer = std::numeric_limits<int64_t>::max();
@@ -248,6 +255,11 @@ void NetworkingLobby::onUpdate(float delta)
     if (NetworkConfig::get()->isServer() || !STKHost::existHost())
         return;
 
+    m_start_button->setVisible(false);
+    m_config_button->setVisible(false);
+    m_config_button->setImage(m_config_texture);
+    m_client_live_joinable = false;
+
     m_ping_update_timer += delta;
     if (m_player_list && m_ping_update_timer > 2.0f)
     {
@@ -317,6 +329,18 @@ void NetworkingLobby::onUpdate(float delta)
             //wait before the current game finish
             msg = _("Please wait for the current game's end.");
         }
+
+        // You can live join or spectator if u have the current play track
+        // and network timer is synchronized
+        if (t &&
+            STKHost::get()->getNetworkTimerSynchronizer()->isSynchronised() &&
+            m_server_live_joinable)
+        {
+            m_client_live_joinable = true;
+        }
+        else
+            m_client_live_joinable = false;
+
         m_timeout_message->setText(msg, false);
         core::stringw total_msg;
         for (auto& string : m_server_info)
@@ -326,6 +350,19 @@ void NetworkingLobby::onUpdate(float delta)
         }
         m_text_bubble->setText(total_msg, true);
         m_cur_starting_timer = std::numeric_limits<int64_t>::max();
+
+        if (m_client_live_joinable)
+        {
+            m_start_button->setVisible(true);
+            //I18N: Live join is displayed in networking lobby to allow players
+            //to join the current started in-progress game
+            m_start_button->setLabel(_("Live join"));
+            //I18N: Spectate is displayed in networking lobby to allow players
+            //to join the current started in-progress game
+            m_config_button->setLabel(_("Spectate"));
+            m_config_button->setImage(m_spectate_texture);
+            m_config_button->setVisible(true);
+        }
         return;
     }
 
@@ -508,15 +545,35 @@ void NetworkingLobby::eventCallback(Widget* widget, const std::string& name,
         m_chat_box->setText("");
     }   // send chat message
     else if (name == m_start_button->m_properties[PROP_ID])
+    {
+        if (m_client_live_joinable)
+        {
+            auto cl = LobbyProtocol::get<ClientLobby>();
+            if (cl)
+                cl->startLiveJoinKartSelection();
+        }
+        else
         {
             // Send a message to the server to start
             NetworkString start(PROTOCOL_LOBBY_ROOM);
             start.addUInt8(LobbyProtocol::LE_REQUEST_BEGIN);
             STKHost::get()->sendToServer(&start, true);
         }
+    }
     else if (name == m_config_button->m_properties[PROP_ID])
     {
         auto cl = LobbyProtocol::get<ClientLobby>();
+        if (m_client_live_joinable && cl)
+        {
+            cl->setSpectator(true);
+            NetworkString start(PROTOCOL_LOBBY_ROOM);
+            start.setSynchronous(true);
+            start.addUInt8(LobbyProtocol::LE_LIVE_JOIN)
+                // is spectating
+                .addUInt8(1);
+            STKHost::get()->sendToServer(&start, true);
+            return;
+        }
         if (cl)
         {
             new ServerConfigurationDialog(

src/states_screens/online/networking_lobby.hpp

@@ -77,7 +77,11 @@ private:
     unsigned m_min_start_game_players;
 
     bool m_allow_change_team, m_has_auto_start_in_server,
-        m_server_configurable;
+        m_server_configurable, m_server_live_joinable,
+        m_client_live_joinable;
+
+    video::ITexture* m_config_texture;
+    video::ITexture* m_spectate_texture;
 
     GUIEngine::IconButtonWidget* m_back_widget;
     GUIEngine::LabelWidget* m_header;
@@ -145,6 +149,7 @@ public:
                             float start_timeout, unsigned server_max_player);
     void setStartingTimerTo(float t);
     void toggleServerConfigButton(bool val)    { m_server_configurable = val; }
+    void toggleServerLiveJoinable(bool val)   { m_server_live_joinable = val; }
 };   // class NetworkingLobby
 
 #endif