Add live join world and kart handling

src/karts/abstract_kart.cpp

@@ -58,6 +58,7 @@ AbstractKart::~AbstractKart()
 // ----------------------------------------------------------------------------
 void AbstractKart::reset()
 {
+    m_live_join_util = 0;
     // important to delete animations before calling reset, as some animations
     // set the kart velocity in their destructor (e.g. cannon) which "reset"
     // can then cancel. See #2738
@@ -192,10 +193,17 @@ void AbstractKart::kartIsInRestNow()
  *  position in case there is a slope. */
 void AbstractKart::makeKartRest()
 {
+    btTransform t = m_starting_transform;
+    if (m_live_join_util != 0)
+    {
+        t.setOrigin(t.getOrigin() +
+            m_starting_transform.getBasis().getColumn(1) * 3.0f);
+    }
+
     btRigidBody *body = getBody();
     body->clearForces();
     body->setLinearVelocity(Vec3(0.0f));
     body->setAngularVelocity(Vec3(0.0f));
-    body->proceedToTransform(m_starting_transform);
+    body->proceedToTransform(t);
-    setTrans(m_starting_transform);
+    setTrans(t);
 }   // makeKartRest

src/karts/abstract_kart.hpp

@@ -75,12 +75,15 @@ private:
     /** Index of kart in world. */
     unsigned int m_world_kart_id;
 
-    btTransform m_starting_transform;
     // ------------------------------------------------------------------------
     void loadKartProperties(const std::string& new_ident,
                             PerPlayerDifficulty difficulty,
                             std::shared_ptr<RenderInfo> ri);
 protected:
+    btTransform m_starting_transform;
+
+    int m_live_join_util;
+
     /** The kart properties. */
     std::unique_ptr<KartProperties> m_kart_properties;
 
@@ -532,6 +535,8 @@ public:
     virtual float getStartupBoostFromStartTicks(int ticks) const = 0;
     // ------------------------------------------------------------------------
     virtual Stars* getStarsEffect() const = 0;
+    // ------------------------------------------------------------------------
+    void setLiveJoinKart(int util_ticks)     { m_live_join_util = util_ticks; }
 };   // AbstractKart
 
 

src/karts/kart.cpp

@@ -1409,6 +1409,23 @@ void Kart::update(int ticks)
 
     Vec3 front(0, 0, getKartLength()*0.5f);
     m_xyz_front = getTrans()(front);
+
+    // Hover the kart above reset position before entering the game
+    if (m_live_join_util != 0 &&
+        (m_live_join_util < World::getWorld()->getTicksSinceStart() ||
+        World::getWorld()->isLiveJoinWorld()))
+    {
+        btRigidBody *body = getBody();
+        body->clearForces();
+        body->setLinearVelocity(Vec3(0.0f));
+        body->setAngularVelocity(Vec3(0.0f));
+        btTransform hovering = m_starting_transform;
+        hovering.setOrigin(hovering.getOrigin() +
+            m_starting_transform.getBasis().getColumn(1) * 3.0f);
+        body->proceedToTransform(hovering);
+        setTrans(hovering);
+    }
+
     // Update the locally maintained speed of the kart (m_speed), which 
     // is used furthermore for engine power, camera distance etc
     updateSpeed();

src/modes/world_status.cpp

@@ -49,7 +49,7 @@ WorldStatus::WorldStatus()
     m_play_track_intro_sound = UserConfigParams::m_music;
     m_play_ready_set_go_sounds = true;
     m_play_racestart_sounds = true;
-
+    m_live_join_world = false;
     IrrlichtDevice *device = irr_driver->getDevice();
 
     if (device->getTimer()->isStopped())
@@ -253,10 +253,13 @@ void WorldStatus::updateTime(int ticks)
                 m_phase = WAIT_FOR_SERVER_PHASE;
                 // In networked races, inform the start game protocol that
                 // the world has been setup
+                if (!m_live_join_world)
+                {
                     auto lobby = LobbyProtocol::get<LobbyProtocol>();
                     assert(lobby);
                     lobby->finishedLoadingWorld();
                 }
+            }
             else
             {
                 if (m_play_ready_set_go_sounds)
@@ -266,6 +269,20 @@ void WorldStatus::updateTime(int ticks)
             return;   // Don't increase time
         case WAIT_FOR_SERVER_PHASE:
         {
+            if (m_live_join_world)
+            {
+                m_auxiliary_ticks++;
+                // Add 3 seconds delay before telling server finish loading
+                // world, so previous (if any) disconnected player has left
+                // fully
+                if (m_auxiliary_ticks == 360)
+                {
+                    auto lobby = LobbyProtocol::get<LobbyProtocol>();
+                    assert(lobby);
+                    lobby->finishedLoadingWorld();
+                }
+                return;
+            }
             return;   // Don't increase time
         }
         case SERVER_READY_PHASE:
@@ -522,3 +539,10 @@ void WorldStatus::unpause()
         !NetworkConfig::get()->isNetworking())
         device->getTimer()->start();
 }   // unpause
+
+//-----------------------------------------------------------------------------
+void WorldStatus::endLiveJoinWorld(int ticks_now)
+{
+    m_live_join_world = false;
+    m_auxiliary_ticks = 0;
+}   // endLiveJoinWorld

src/modes/world_status.hpp

@@ -136,6 +136,8 @@ private:
 
     bool            m_engines_started;
 
+    bool            m_live_join_world;
+
     void startEngines();
 
 public:
@@ -212,7 +214,12 @@ public:
     int getTicksSinceStart() const { return m_count_up_ticks; }
     // ------------------------------------------------------------------------
     int getAuxiliaryTicks() const { return m_auxiliary_ticks; }
-
+    // ------------------------------------------------------------------------
+    bool isLiveJoinWorld() const { return m_live_join_world; }
+    // ------------------------------------------------------------------------
+    void setLiveJoinWorld(bool val) { m_live_join_world = val; }
+    // ------------------------------------------------------------------------
+    void endLiveJoinWorld(int ticks_now);
 };   // WorldStatus