1 //
2 //  SuperTuxKart - a fun racing game with go-kart
3 //  Copyright (C) 2018 Joerg Henrichs
4 //
5 //  This program is free software; you can redistribute it and/or
6 //  modify it under the terms of the GNU General Public License
7 //  as published by the Free Software Foundation; either version 3
8 //  of the License, or (at your option) any later version.
9 //
10 //  This program is distributed in the hope that it will be useful,
11 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
12 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 //  GNU General Public License for more details.
14 //
15 //  You should have received a copy of the GNU General Public License
16 //  along with this program; if not, write to the Free Software
17 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
18 
19 #ifndef HEADER_NETWORK_ITEM_MANAGER_HPP
20 #define HEADER_NETWORK_ITEM_MANAGER_HPP
21 
22 #include "items/item_event_info.hpp"
23 #include "items/item_manager.hpp"
24 #include "network/rewinder.hpp"
25 #include "utils/cpp2011.hpp"
26 #include "utils/synchronised.hpp"
27 
28 #include <map>
29 #include <memory>
30 #include <mutex>
31 
32 class STKPeer;
33 
34 /** \ingroup items
35  *  The network item manager is responsible for handling all network related
36  *  item manager tasks - synchronisation between clients and servers. It
37  *  maintains one 'confirmed' state on the clients, based on the latest
38  *  server update. The server sends updates that only contains the delta
39  *  between the last confirmed and the current server state. Eash client
40  *  confirms to the server which deltas it has received. Once all clients
41  *  have received a delta, the server will remove it from the list of
42  *  deltas.
43   */
44 class NetworkItemManager : public Rewinder, public ItemManager
45 {
46 private:
47 
48     /** A client stores a 'confirmed' item event state, which is based on the
49       * server data. This is used in case of rewind. */
50     std::vector<ItemState*> m_confirmed_state;
51 
52     /** The switch ticks value at the lime of the last confirmed state. */
53     int m_confirmed_switch_ticks;
54 
55     /** Time at which m_confirmed_state was taken. */
56     int m_confirmed_state_time;
57 
58     /** Allow remove or add peer live. */
59     std::mutex m_live_players_mutex;
60 
61     /** Stores on the server the latest confirmed tick from each client. */
62     std::map<std::weak_ptr<STKPeer>, int32_t,
63         std::owner_less<std::weak_ptr<STKPeer> > > m_last_confirmed_item_ticks;
64 
65     /** List of all items events. */
66     Synchronised< std::vector<ItemEventInfo> > m_item_events;
67 
68     void forwardTime(int ticks);
69 public:
70 
71     static bool m_network_item_debugging;
72 
73     NetworkItemManager();
74     virtual ~NetworkItemManager();
75     virtual void reset() OVERRIDE;
76     virtual void setItemConfirmationTime(std::weak_ptr<STKPeer> peer,
77                                          int ticks) OVERRIDE;
78     virtual void  collectedItem(ItemState *item, AbstractKart *kart) OVERRIDE;
79     virtual void  switchItems() OVERRIDE;
80     virtual Item* dropNewItem(ItemState::ItemType type,
81                               const AbstractKart *kart,
82                               const Vec3 *server_xyz = NULL,
83                               const Vec3 *server_normal = NULL) OVERRIDE;
84     virtual BareNetworkString* saveState(std::vector<std::string>* ru)
85         OVERRIDE;
86     virtual void restoreState(BareNetworkString *buffer, int count) OVERRIDE;
87     // ------------------------------------------------------------------------
rewindToEvent(BareNetworkString * bns)88     virtual void rewindToEvent(BareNetworkString *bns) OVERRIDE {};
89     // ------------------------------------------------------------------------
saveTransform()90     virtual void saveTransform() OVERRIDE {};
91     // ------------------------------------------------------------------------
computeError()92     virtual void computeError() OVERRIDE {};
93     // ------------------------------------------------------------------------
undoState(BareNetworkString * buffer)94     virtual void undoState(BareNetworkString *buffer) OVERRIDE {};
95     // ------------------------------------------------------------------------
undoEvent(BareNetworkString *)96     virtual void undoEvent(BareNetworkString*) OVERRIDE {};
97     // ------------------------------------------------------------------------
addLiveJoinPeer(std::weak_ptr<STKPeer> peer)98     void addLiveJoinPeer(std::weak_ptr<STKPeer> peer)
99     {
100         std::lock_guard<std::mutex> lock(m_live_players_mutex);
101         m_last_confirmed_item_ticks[peer] = 0;
102     }
103     // ------------------------------------------------------------------------
erasePeerInGame(std::weak_ptr<STKPeer> peer)104     void erasePeerInGame(std::weak_ptr<STKPeer> peer)
105     {
106         std::lock_guard<std::mutex> lock(m_live_players_mutex);
107         m_last_confirmed_item_ticks.erase(peer);
108     }
109     // ------------------------------------------------------------------------
110     void saveCompleteState(BareNetworkString* buffer) const;
111     // ------------------------------------------------------------------------
112     void restoreCompleteState(const BareNetworkString& buffer);
113     // ------------------------------------------------------------------------
114     void initServer();
115 
116 };   // NetworkItemManager
117 
118 #endif
119