From 29c6dae77623a6384cbacd777ed2547e93edf1ae Mon Sep 17 00:00:00 2001
From: fickleheart <fickle@tinted.red>
Date: Tue, 19 Mar 2019 23:39:04 -0500
Subject: [PATCH] Add command to lower netreplay sync frequency

This makes for smaller replay files while keeping
sync checks in place!
---
 src/d_netcmd.c |  1 +
 src/g_game.c   | 12 ++++++++++--
 src/g_game.h   |  2 +-
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/d_netcmd.c b/src/d_netcmd.c
index 0522fd71..b13df51e 100644
--- a/src/d_netcmd.c
+++ b/src/d_netcmd.c
@@ -811,6 +811,7 @@ void D_RegisterClientCommands(void)
 	COM_AddCommand("displayplayer", Command_Displayplayer_f);
 
 	CV_RegisterVar(&cv_recordmultiplayerdemos);
+	CV_RegisterVar(&cv_netdemosyncquality);
 
 	// FIXME: not to be here.. but needs be done for config loading
 	CV_RegisterVar(&cv_usegamma);
diff --git a/src/g_game.c b/src/g_game.c
index 0b52c528..7335939c 100644
--- a/src/g_game.c
+++ b/src/g_game.c
@@ -341,6 +341,9 @@ INT16 prevmap, nextmap;
 static CV_PossibleValue_t recordmultiplayerdemos_cons_t[] = {{0, "Disabled"}, {1, "Manual Save"}, {2, "Auto Save"}, {0, NULL}};
 consvar_t cv_recordmultiplayerdemos = {"netdemo_record", "Manual Save", CV_SAVE, recordmultiplayerdemos_cons_t, NULL, 0, NULL, NULL, 0, 0, NULL};
 
+static CV_PossibleValue_t netdemosyncquality_cons_t[] = {{1, "MIN"}, {35, "MAX"}, {0, NULL}};
+consvar_t cv_netdemosyncquality = {"netdemo_syncquality", "1", CV_SAVE, netdemosyncquality_cons_t, NULL, 0, NULL, NULL, 0, 0, NULL};
+
 static UINT8 *savebuffer;
 
 // Analog Control
@@ -5221,7 +5224,7 @@ void G_GhostAddHit(INT32 playernum, mobj_t *victim)
 
 void G_WriteAllGhostTics(void)
 {
-	INT32 i;
+	INT32 i, counter = leveltime;
 	for (i = 0; i < MAXPLAYERS; i++)
 	{
 		if (!playeringame[i] || players[i].spectator)
@@ -5230,6 +5233,11 @@ void G_WriteAllGhostTics(void)
 		if (!players[i].mo)
 			continue;
 
+		counter++;
+
+		if (counter % cv_netdemosyncquality.value != 0) // Only write 1 in this many ghost datas per tic to cut down on multiplayer replay size.
+			continue;
+
 		WRITEUINT8(demo_p, i);
 		G_WriteGhostTic(players[i].mo, i);
 	}
@@ -5264,7 +5272,7 @@ void G_WriteGhostTic(mobj_t *ghost, INT32 playernum)
 	if (abs(ghost->x-oldghost[playernum].x) > MAXMOM
 	|| abs(ghost->y-oldghost[playernum].y) > MAXMOM
 	|| abs(ghost->z-oldghost[playernum].z) > MAXMOM
-	|| (leveltime & 255) == 1) // Hack to enable slightly nicer resyncing
+	|| ((UINT8)(leveltime & 255) > 0 && (UINT8)(leveltime & 255) <= (UINT8)cv_netdemosyncquality.value)) // Hack to enable slightly nicer resyncing
 	{
 		oldghost[playernum].x = ghost->x;
 		oldghost[playernum].y = ghost->y;
diff --git a/src/g_game.h b/src/g_game.h
index e5f94793..f78a06d0 100644
--- a/src/g_game.h
+++ b/src/g_game.h
@@ -38,7 +38,7 @@ extern boolean playeringame[MAXPLAYERS];
 // demoplaying back and demo recording
 extern boolean demoplayback, titledemo, fromtitledemo, demorecording, timingdemo, demosaved, demodefersave, demo_loadfiles, demo_ignorefiles;
 extern tic_t demosavebutton;
-extern consvar_t cv_recordmultiplayerdemos;
+extern consvar_t cv_recordmultiplayerdemos, cv_netdemosyncquality;
 
 // Quit after playing a demo from cmdline.
 extern boolean singledemo;