Added network load balancing

- Guests can now attempt to match latency with the arbitrator.
(net_loadbalance)
- Added althud feature to show arbitrator and local latency.
(hud_showlag 1 is on for netgames, 2 is always on)

src/d_net.cpp

@@ -117,6 +117,7 @@ int				playerfornode[MAXNETNODES];
 int 			maketic;
 int 			skiptics;
 int 			ticdup; 		
+int				arb_maketic;							// Arbitrators maketic difference
 
 void D_ProcessEvents (void); 
 void G_BuildTiccmd (ticcmd_t *cmd); 
@@ -151,6 +152,8 @@ CUSTOM_CVAR (Bool, cl_capfps, false, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 	}
 }
 
+CVAR(Bool, net_loadbalance, true, CVAR_SERVERINFO)
+
 // [RH] Special "ticcmds" get stored in here
 static struct TicSpecial
 {
@@ -347,6 +350,9 @@ int NetbufferSize ()
 		k += netbuffer[k] + 1;
 	}
 
+	if (doomcom.remotenode == nodeforplayer[Net_Arbitrator])
+		k++;
+
 	if (netbuffer[0] & NCMD_MULTI)
 	{
 		count = netbuffer[k];
@@ -570,6 +576,9 @@ bool HGetPacket (void)
 
 	if (doomcom.datalength != NetbufferSize ())
 	{
+		Printf("Bad packet length %i (calculated %i)\n",
+			doomcom.datalength, NetbufferSize());
+
 		if (debugfile)
 			fprintf (debugfile,"---bad packet length %i (calculated %i)\n",
 				doomcom.datalength, NetbufferSize());
@@ -782,6 +791,11 @@ void GetPackets (void)
 			}
 		}
 
+		if (netconsole == Net_Arbitrator)
+		{
+			arb_maketic = netbuffer[k++];
+		}
+
 		playerbytes[0] = netconsole;
 		if (netbuffer[0] & NCMD_MULTI)
 		{
@@ -1190,6 +1204,12 @@ void NetUpdate (void)
 			}
 		}
 
+		if (consoleplayer == Net_Arbitrator)
+		{
+			// The number of tics we just made should be removed from the count.
+			netbuffer[k++] = ((maketic - newtics - gametic) / ticdup);
+		}
+
 		if (numtics > 0)
 		{
 			int l;
@@ -1298,10 +1318,16 @@ void NetUpdate (void)
 			// very jerky. The way I have it written right now basically means
 			// that it won't adapt. Fortunately, player prediction helps
 			// alleviate the lag somewhat.
-
-			if (NetMode != NET_PacketServer)
+			int average = 0;
+			if (net_loadbalance)
+				average = (((maketic - newtics - gametic) / ticdup) + arb_maketic) / 2;
+			if (NetMode == NET_PeerToPeer)
 			{
-				mastertics = nettics[nodeforplayer[Net_Arbitrator]];
+				mastertics = nettics[nodeforplayer[Net_Arbitrator]] + average;
+			}
+			else if (NetMode == NET_PacketServer)
+			{
+				mastertics = mastertics + average;
 			}
 			if (nettics[0] <= mastertics)
 			{
@@ -2713,7 +2739,7 @@ void Net_SkipCommand (int type, BYTE **stream)
 CCMD (pings)
 {
 	int i;
-
+	Printf("%d (%d ms) arbitrator buffer time\n", arb_maketic * ticdup, (arb_maketic * ticdup) * (1000 / TICRATE));
 	for (i = 0; i < MAXPLAYERS; i++)
 		if (playeringame[i])
 			Printf ("% 4d %s\n", currrecvtime[i] - lastrecvtime[i],

src/d_net.h

@@ -143,6 +143,7 @@ extern	struct ticcmd_t	localcmds[LOCALCMDTICS];
 
 extern	int 			maketic;
 extern	int 			nettics[MAXNETNODES];
+extern	int				arb_maketic;
 
 extern	ticcmd_t		netcmds[MAXPLAYERS][BACKUPTICS];
 extern	int 			ticdup;

src/g_shared/shared_hud.cpp

@@ -37,6 +37,7 @@
 // copy would be.
 
 #include "doomtype.h"
+#include "doomdef.h"
 #include "v_video.h"
 #include "gi.h"
 #include "c_cvars.h"
@@ -48,6 +49,7 @@
 #include "p_local.h"
 #include "doomstat.h"
 #include "g_level.h"
+#include "d_net.h"
 
 #include <time.h>
 
@@ -73,6 +75,7 @@ CVAR (Bool,  hud_showscore,		false,	CVAR_ARCHIVE);	// for user maintained score
 CVAR (Bool,  hud_showweapons,	true, CVAR_ARCHIVE);	// Show weapons collected
 CVAR (Int ,  hud_showtime,		0,	    CVAR_ARCHIVE);	// Show time on HUD
 CVAR (Int ,  hud_timecolor,		CR_GOLD,CVAR_ARCHIVE);	// Color of in-game time on HUD
+CVAR (Int ,  hud_showlag,		0, CVAR_ARCHIVE);		// Show input latency (maketic - gametic difference)
 
 CVAR (Int, hud_ammo_red, 25, CVAR_ARCHIVE)					// ammo percent less than which status is red    
 CVAR (Int, hud_ammo_yellow, 50, CVAR_ARCHIVE)				// ammo percent less is yellow more green        
@@ -917,6 +920,49 @@ static void DrawTime()
 	DrawHudText(SmallFont, hud_timecolor, timeString, hudwidth - width, height, FRACUNIT);
 }
 
+//---------------------------------------------------------------------------
+//
+// Draw in-game latency
+//
+//---------------------------------------------------------------------------
+
+static void DrawLatency()
+{
+	if (hud_showlag <= 0 ||
+		(hud_showlag == 1 && !netgame) ||
+		hud_showlag > 2)
+	{
+		return;
+	}
+
+	int localdelay = (maketic - gametic) * (1000 / TICRATE);
+	int arbitratordelay = (arb_maketic * ticdup) * (1000 / TICRATE);
+	int color = CR_GREEN;
+	if (MAX(localdelay, arbitratordelay) > 200)
+	{
+		color = CR_YELLOW;
+	}
+	if (MAX(localdelay, arbitratordelay) > 400)
+	{
+		color = CR_ORANGE;
+	}
+	if (MAX(localdelay, arbitratordelay) >= ((BACKUPTICS / 2 - 1) * ticdup) * (1000 / TICRATE))
+	{
+		color = CR_RED;
+	}
+
+	char tempstr[32];
+
+	const int millis = (level.time % TICRATE) * (1000 / TICRATE);
+	mysnprintf(tempstr, sizeof(tempstr), "a:%dms - l:%dms", arbitratordelay, localdelay);
+
+	const int characterCount = strlen(tempstr);
+	const int width = SmallFont->GetCharWidth('0') * characterCount + 2; // small offset from screen's border
+	const int height = SmallFont->GetHeight() * 2;
+
+	DrawHudText(SmallFont, color, tempstr, hudwidth - width, height, FRACUNIT);
+}
+
 
 //---------------------------------------------------------------------------
 //
@@ -982,6 +1028,7 @@ void DrawHUD()
 		if (idmypos) DrawCoordinates(CPlayer);
 
 		DrawTime();
+		DrawLatency();
 	}
 	else
 	{

wadsrc/static/menudef.txt

@@ -805,6 +805,13 @@ OptionValue "AltHUDTime"
 	9, "System"
 }
 
+OptionValue "AltHUDLag"
+{
+	0, "Off"
+	1, "Netgames only"
+	2, "Always"
+}
+
 OptionMenu "AltHUDOptions"
 {
 	Title "Alternative HUD"
@@ -819,6 +826,7 @@ OptionMenu "AltHUDOptions"
 	Option "Show weapons",							"hud_showweapons", "OnOff"
 	Option "Show time",								"hud_showtime", "AltHUDTime"
 	Option "Time color",							"hud_timecolor", "TextColors"
+	Option "Show network latency",					"hud_showlag", "AltHUDLag"
 	Slider "Red ammo display below %",				"hud_ammo_red", 0, 100, 1, 0
 	Slider "Yellow ammo display below %",			"hud_ammo_yellow", 0, 100, 1, 0
 	Slider "Red health display below",				"hud_health_red", 0, 100, 1, 0