From f68dbed5351c33ec975445eb832e75b5e68a6fb2 Mon Sep 17 00:00:00 2001
From: Techjar <tecknojar@gmail.com>
Date: Mon, 9 Jul 2018 16:45:52 -0400
Subject: [PATCH] NetPlay: Bundle multiple local pads into one packet This
 saves a significant amount of bandwidth with multiple controllers on one
 client, as most of the packet is just protocol overhead.

---
 Source/Core/Core/NetPlayClient.cpp | 40 +++++++++++++++++++-----------
 Source/Core/Core/NetPlayClient.h   |  2 +-
 Source/Core/Core/NetPlayServer.cpp | 40 +++++++++++++++++-------------
 3 files changed, 49 insertions(+), 33 deletions(-)

diff --git a/Source/Core/Core/NetPlayClient.cpp b/Source/Core/Core/NetPlayClient.cpp
index 99863ce273..7fa576a3ef 100644
--- a/Source/Core/Core/NetPlayClient.cpp
+++ b/Source/Core/Core/NetPlayClient.cpp
@@ -334,15 +334,20 @@ unsigned int NetPlayClient::OnData(sf::Packet& packet)
 
   case NP_MSG_PAD_DATA:
   {
-    PadMapping map = 0;
-    GCPadStatus pad;
-    packet >> map >> pad.button >> pad.analogA >> pad.analogB >> pad.stickX >> pad.stickY >>
-        pad.substickX >> pad.substickY >> pad.triggerLeft >> pad.triggerRight >> pad.isConnected;
+    while (!packet.endOfPacket())
+    {
+      PadMapping map;
+      packet >> map;
 
-    // Trusting server for good map value (>=0 && <4)
-    // add to pad buffer
-    m_pad_buffer.at(map).Push(pad);
-    m_gc_pad_event.Set();
+      GCPadStatus pad;
+      packet >> pad.button >> pad.analogA >> pad.analogB >> pad.stickX >> pad.stickY >>
+          pad.substickX >> pad.substickY >> pad.triggerLeft >> pad.triggerRight >> pad.isConnected;
+
+      // Trusting server for good map value (>=0 && <4)
+      // add to pad buffer
+      m_pad_buffer.at(map).Push(pad);
+      m_gc_pad_event.Set();
+    }
   }
   break;
 
@@ -778,15 +783,12 @@ void NetPlayClient::SendChatMessage(const std::string& msg)
 }
 
 // called from ---CPU--- thread
-void NetPlayClient::SendPadState(const int in_game_pad, const GCPadStatus& pad)
+void NetPlayClient::AddPadStateToPacket(const int in_game_pad, const GCPadStatus& pad,
+                                        sf::Packet& packet)
 {
-  sf::Packet packet;
-  packet << static_cast<MessageId>(NP_MSG_PAD_DATA);
   packet << static_cast<PadMapping>(in_game_pad);
   packet << pad.button << pad.analogA << pad.analogB << pad.stickX << pad.stickY << pad.substickX
          << pad.substickY << pad.triggerLeft << pad.triggerRight << pad.isConnected;
-
-  SendAsync(std::move(packet));
 }
 
 // called from ---CPU--- thread
@@ -1000,6 +1002,10 @@ bool NetPlayClient::GetNetPads(const int pad_nb, GCPadStatus* pad_status)
   // clients.
   if (IsFirstInGamePad(pad_nb))
   {
+    sf::Packet packet;
+    packet << static_cast<MessageId>(NP_MSG_PAD_DATA);
+
+    bool send_packet = false;
     const int num_local_pads = NumLocalPads();
     for (int local_pad = 0; local_pad < num_local_pads; local_pad++)
     {
@@ -1023,10 +1029,14 @@ bool NetPlayClient::GetNetPads(const int pad_nb, GCPadStatus* pad_status)
         // add to buffer
         m_pad_buffer[ingame_pad].Push(*pad_status);
 
-        // send
-        SendPadState(ingame_pad, *pad_status);
+        // add to packet
+        AddPadStateToPacket(ingame_pad, *pad_status, packet);
+        send_packet = true;
       }
     }
+
+    if (send_packet)
+      SendAsync(std::move(packet));
   }
 
   // Now, we either use the data pushed earlier, or wait for the
diff --git a/Source/Core/Core/NetPlayClient.h b/Source/Core/Core/NetPlayClient.h
index c4ababf068..464337b9ea 100644
--- a/Source/Core/Core/NetPlayClient.h
+++ b/Source/Core/Core/NetPlayClient.h
@@ -159,7 +159,7 @@ private:
   void SendStopGamePacket();
 
   void UpdateDevices();
-  void SendPadState(int in_game_pad, const GCPadStatus& np);
+  void AddPadStateToPacket(int in_game_pad, const GCPadStatus& np, sf::Packet& packet);
   void SendWiimoteState(int in_game_pad, const NetWiimote& nw);
   unsigned int OnData(sf::Packet& packet);
   void Send(const sf::Packet& packet);
diff --git a/Source/Core/Core/NetPlayServer.cpp b/Source/Core/Core/NetPlayServer.cpp
index 78ad81364c..1a185a6c7d 100644
--- a/Source/Core/Core/NetPlayServer.cpp
+++ b/Source/Core/Core/NetPlayServer.cpp
@@ -526,24 +526,30 @@ unsigned int NetPlayServer::OnData(sf::Packet& packet, Client& player)
     if (player.current_game != m_current_game)
       break;
 
-    PadMapping map = 0;
-    GCPadStatus pad;
-    packet >> map >> pad.button >> pad.analogA >> pad.analogB >> pad.stickX >> pad.stickY >>
-        pad.substickX >> pad.substickY >> pad.triggerLeft >> pad.triggerRight >> pad.isConnected;
-
-    // If the data is not from the correct player,
-    // then disconnect them.
-    if (m_pad_map.at(map) != player.pid)
-    {
-      return 1;
-    }
-
-    // Relay to clients
     sf::Packet spac;
-    spac << (MessageId)NP_MSG_PAD_DATA;
-    spac << map << pad.button << pad.analogA << pad.analogB << pad.stickX << pad.stickY
-         << pad.substickX << pad.substickY << pad.triggerLeft << pad.triggerRight
-         << pad.isConnected;
+    spac << static_cast<MessageId>(NP_MSG_PAD_DATA);
+
+    while (!packet.endOfPacket())
+    {
+      PadMapping map;
+      packet >> map;
+
+      // If the data is not from the correct player,
+      // then disconnect them.
+      if (m_pad_map.at(map) != player.pid)
+      {
+        return 1;
+      }
+
+      GCPadStatus pad;
+      packet >> pad.button >> pad.analogA >> pad.analogB >> pad.stickX >> pad.stickY >>
+          pad.substickX >> pad.substickY >> pad.triggerLeft >> pad.triggerRight >> pad.isConnected;
+
+      // Add to packet for relay to clients
+      spac << map << pad.button << pad.analogA << pad.analogB << pad.stickX << pad.stickY
+           << pad.substickX << pad.substickY << pad.triggerLeft << pad.triggerRight
+           << pad.isConnected;
+    }
 
     SendToClients(spac, player.pid);
   }