Add support for the demo version of the game

This allows the demo version of the game to be used, both for playing on demo servers, or for hosting a demo server

code/client/cl_main.cpp

@@ -3689,6 +3689,8 @@ void CL_ServerInfoPacket( netadr_t from, msg_t *msg ) {
 	char	*infoString;
 	int		prot;
 	char	*gamename;
+	char	*pszVersion;
+	char	*pszServerType;
 	qboolean gameMismatch;
 
 	infoString = MSG_ReadString( msg );
@@ -3717,12 +3719,44 @@ void CL_ServerInfoPacket( netadr_t from, msg_t *msg ) {
 #ifdef LEGACY_PROTOCOL
 	   && prot != com_legacyprotocol->integer
 #endif
+		&& (com_target_demo->integer || prot != protocol_version_demo)
 	  )
 	{
 		Com_DPrintf( "Different protocol info packet: %s\n", infoString );
 		return;
 	}
 
+	if (!com_target_demo->integer && prot == protocol_version_demo) {
+		Com_DPrintf("Full version found compatible demo protocol version. %s\n", infoString);
+	}
+
+    pszVersion = Info_ValueForKey(infoString, "gamever");
+    pszServerType = Info_ValueForKey(infoString, "serverType");
+
+	if (!*pszVersion) {
+		return;
+	}
+
+	if (*pszVersion == 'd') {
+		pszVersion++;
+	}
+
+    if (com_target_game->integer >= target_game_e::TG_MOHTT) {
+        if (atoi(pszServerType) == target_game_e::TG_MOHTT) {
+            if (fabs(atof(pszVersion)) < 2.3f) {
+				return;
+            }
+        } else {
+            if (fabs(atof(pszVersion)) < 2.1f) {
+				return;
+            }
+        }
+    } else {
+        if (fabs(atof(pszVersion) - com_target_version->value) > 0.1f) {
+			return;
+        }
+    }
+
 	// iterate servers waiting for ping response
 	for (i=0; i<MAX_PINGREQUESTS; i++)
 	{

code/client/cl_ui.cpp

@@ -4986,6 +4986,20 @@ void UI_HideStatistics_f()
     statsUpdater.CancelEventsOfType(EV_StatsUpdater_UpdateStats);
 }
 
+/*
+====================
+UI_SalesScreen_f
+====================
+*/
+void UI_SalesScreen_f()
+{
+    if (random() > 0.5) {
+        Cbuf_AddText("pushmenu sales_splash1\n");
+    } else {
+        Cbuf_AddText("pushmenu sales_splash2\n");
+    }
+}
+
 /*
 ====================
 CL_ShutdownUI
@@ -5256,6 +5270,7 @@ void CL_InitializeUI(void)
     Cmd_AddCommand("-statistics", UI_HideStatistics_f);
     Cmd_AddCommand("setreturnmenu", UI_SetReturnMenuToCurrent);
     Cmd_AddCommand("gotoreturnmenu", UI_PushReturnMenu_f);
+    Cmd_AddCommand("salesscreen", UI_SalesScreen_f);
 
     if (developer->integer) {
         UColor bgColor;

code/client/cl_uiserverlist.cpp

@@ -1040,6 +1040,7 @@ void UpdateServerListCallBack(GServerList serverlist, int msg, void* instance, v
     {
         const char* pszHostName;
         bool bDiffVersion;
+        bool bIsDemo;
         str sServerName;
         str sPlayers;
         const char* pszGameVer;
@@ -1047,12 +1048,14 @@ void UpdateServerListCallBack(GServerList serverlist, int msg, void* instance, v
 
         pszHostName = ServerGetStringValue(server, "hostname", "(NONE)");
         bDiffVersion = false;
+        bIsDemo = false;
         pszGameVer = ServerGetStringValue(server, "gamever", "1.00");
         pszGameVerNumber = pszGameVer;
 
         if (pszGameVerNumber[0] == 'd') {
             // demo server
             pszGameVerNumber++;
+            bIsDemo = true;
         }
 
         if (com_target_game->integer >= target_game_e::TG_MOHTT) {
@@ -1077,7 +1080,11 @@ void UpdateServerListCallBack(GServerList serverlist, int msg, void* instance, v
             }
         }
         // always show the version
-        sServerName = va(" (%s) %s", pszGameVer, pszHostName);
+        if (!bIsDemo) {
+            sServerName = va(" (%s) %s", pszGameVerNumber, pszHostName);
+        } else {
+            sServerName = va(" (d%s) %s", pszGameVerNumber, pszHostName);
+        }
 
         iRealIP = inet_addr(ServerGetAddress(server));
         iPort = ServerGetIntValue(server, "hostport", PORT_SERVER);

code/gamespy/sv_gamespy.c

@@ -55,6 +55,13 @@ static const char *GS_GAME_NAME[] =
     "mohaab"
 };
 
+static const char *GS_GAME_NAME_DEMO[] =
+{
+    "mohaa",
+    "mohaas",
+    "mohaabd"
+};
+
 static const char *GS_GAME_VERSION[] =
 {
     TARGET_GAME_VERSION_MOH,
@@ -98,7 +105,11 @@ unsigned int GS_GetCurrentGameID() {
 }
 
 const char* GS_GetGameName(unsigned int index) {
+    if (!com_target_demo->integer) {
         return GS_GAME_NAME[index];
+    } else {
+        return GS_GAME_NAME_DEMO[index];
+    }
 }
 
 const char* GS_GetCurrentGameName() {
@@ -110,7 +121,11 @@ const char* GS_GetGameVersion(unsigned int index) {
 }
 
 const char* GS_GetCurrentGameVersion() {
+    if (!com_target_demo->integer || com_target_game->integer <= TG_MOH) {
         return GS_GetGameVersion(com_target_game->integer);
+    } else {
+        return va("d%s", GS_GetGameVersion(com_target_game->integer));
+    }
 }
 
 static const char *ConvertMapFilename(const char *mapname)
@@ -130,7 +145,6 @@ static void basic_callback(char *outbuf, int maxlen, void *userdata)
 {
     Info_SetValueForKey(outbuf, "gamename", GS_GetCurrentGameName());
     Info_SetValueForKey(outbuf, "gamever", GS_GetCurrentGameVersion());
-
     Info_SetValueForKey(outbuf, "location", va("%i", sv_location->integer));
 
     if (sv_debug_gamespy->integer) {

code/qcommon/common.c

@@ -123,6 +123,10 @@ cvar_t  *con_autochat;
 cvar_t	*precache;
 cvar_t	*com_target_game;
 cvar_t	*com_target_version;
+cvar_t	*com_target_demo;
+
+int protocol_version_demo;
+int protocol_version_full;
 
 // com_speeds times
 int		time_game;
@@ -1652,6 +1656,7 @@ void Com_Init( char *commandLine ) {
 	CL_InitKeyCommands();
 
 	com_target_game = Cvar_Get("com_target_game", "0", CVAR_LATCH | CVAR_PROTECTED);
+	com_target_demo = Cvar_Get("com_target_demo", "0", CVAR_LATCH | CVAR_PROTECTED);
 	com_target_version = Cvar_Get("com_target_version", "0.00", CVAR_ROM);
 	com_standalone = Cvar_Get("com_standalone", "0", CVAR_ROM);
 	com_basegame = Cvar_Get("com_basegame", BASEGAME, CVAR_INIT);
@@ -2996,15 +3001,21 @@ int QDECL Com_strCompare( const void *a, const void *b )
     return strcmp( *pa, *pb );
 }
 
-void Com_InitTargetGameWithType(target_game_e target_game)
+void Com_InitTargetGameWithType(target_game_e target_game, qboolean bIsDemo)
 {
 	const char* protocol;
 
     switch (target_game)
     {
     case TG_MOH:
+		if (!bIsDemo) {
 			Cvar_Set("com_protocol", va("%i", PROTOCOL_MOH));
 			Cvar_Set("com_legacyprotocol", va("%i", PROTOCOL_MOH));
+		} else {
+			Cvar_Set("com_protocol", va("%i", PROTOCOL_MOH_DEMO));
+			Cvar_Set("com_legacyprotocol", va("%i", PROTOCOL_MOH_DEMO));
+        }
+		protocol_version_demo = protocol_version_full = PROTOCOL_MOH;
 		Cvar_Set("com_target_version", TARGET_GAME_VERSION_MOH);
 		Cvar_Set("com_target_extension", PRODUCT_EXTENSION_MOH);
 		Cvar_Set("com_gamename", TARGET_GAME_NAME_MOH);
@@ -3013,22 +3024,50 @@ void Com_InitTargetGameWithType(target_game_e target_game)
         break;
 
     case TG_MOHTA:
+		if (!bIsDemo) {
 			Cvar_Set("com_protocol", va("%i", PROTOCOL_MOHTA));
             Cvar_Set("com_legacyprotocol", va("%i", PROTOCOL_MOHTA));
+		} else {
+			Cvar_Set("com_protocol", va("%i", PROTOCOL_MOHTA_DEMO));
+            Cvar_Set("com_legacyprotocol", va("%i", PROTOCOL_MOHTA_DEMO));
+		}
+		protocol_version_demo = PROTOCOL_MOHTA_DEMO;
+		protocol_version_full = PROTOCOL_MOHTA;
 		Cvar_Set("com_target_version", TARGET_GAME_VERSION_MOHTA);
 		Cvar_Set("com_target_extension", PRODUCT_EXTENSION_MOHTA);
 		Cvar_Set("com_gamename", TARGET_GAME_NAME_MOHTA);
+		if (!bIsDemo) {
 			Cvar_Set("fs_basegame", "mainta");
+		} else {
+			// Targeting a demo
+			Cvar_Set("fs_basegame", "demota");
+		}
         break;
 
     case TG_MOHTT:
 		// mohta and mohtt use the same protocol version number
+		if (!bIsDemo) {
 			Cvar_Set("com_protocol", va("%i", PROTOCOL_MOHTA));
             Cvar_Set("com_legacyprotocol", va("%i", PROTOCOL_MOHTA));
+            Cvar_Set("com_protocol_alt", va("%i", PROTOCOL_MOHTA_DEMO));
             Cvar_Set("com_target_version", TARGET_GAME_VERSION_MOHTT);
+		} else {
+			Cvar_Set("com_protocol", va("%i", PROTOCOL_MOHTA_DEMO));
+            Cvar_Set("com_legacyprotocol", va("%i", PROTOCOL_MOHTA_DEMO));
+            Cvar_Set("com_protocol_alt", va("%i", PROTOCOL_MOHTA));
+            Cvar_Set("com_target_version", TARGET_GAME_VERSION_MOHTT_DEMO);
+        }
+        protocol_version_demo = PROTOCOL_MOHTA_DEMO;
+        protocol_version_full = PROTOCOL_MOHTA;
+        Cvar_Set("com_protocol_alt", va("%i", PROTOCOL_MOHTA));
 		Cvar_Set("com_target_extension", PRODUCT_EXTENSION_MOHTT);
 		Cvar_Set("com_gamename", TARGET_GAME_NAME_MOHTT);
+		if (!bIsDemo) {
 			Cvar_Set("fs_basegame", "maintt");
+		} else {
+			// Targeting a demo
+			Cvar_Set("fs_basegame", "demott");
+		}
         break;
 
     default:
@@ -3045,7 +3084,7 @@ Com_InitTargetGame
 ===============
 */
 void Com_InitTargetGame() {
-	Com_InitTargetGameWithType((target_game_e)com_target_game->integer);
+	Com_InitTargetGameWithType((target_game_e)com_target_game->integer, com_target_demo->integer);
 }
 
 #ifdef __cplusplus

code/qcommon/q_shared.h

@@ -39,6 +39,7 @@ extern "C" {
 #define GAME_EXTENSION_MOH				"main"
 #define PRODUCT_EXTENSION_MOH			"Allied Assault"
 #define TARGET_GAME_VERSION_MOH			"1.12"
+#define TARGET_GAME_PROTOCOL_DEMO_MOH	6
 #define TARGET_GAME_PROTOCOL_MOH		8
 #define TARGET_GAME_NAME_MOH			"mohaa"
 
@@ -49,6 +50,7 @@ extern "C" {
 #define GAME_EXTENSION_MOHTA			"mainta"
 #define PRODUCT_EXTENSION_MOHTA			"Spearhead"
 #define TARGET_GAME_VERSION_MOHTA		"2.16"
+#define TARGET_GAME_PROTOCOL_MIN_MOHTA	16
 #define TARGET_GAME_PROTOCOL_MOHTA		17
 #define TARGET_GAME_NAME_MOHTA			"mohaas"
 
@@ -60,6 +62,8 @@ extern "C" {
 #define PRODUCT_EXTENSION_MOHTT			"Breakthrough"
 // The version string must be equal or above 2.0 to be able to connect to breakthrough servers
 #define	TARGET_GAME_VERSION_MOHTT		"2.41"
+#define	TARGET_GAME_VERSION_MOHTT_DEMO	"0.31"
+#define TARGET_GAME_PROTOCOL_MIN_MOHTT	16
 #define TARGET_GAME_PROTOCOL_MOHTT		17
 #define TARGET_GAME_NAME_MOHTT			"mohaab"
 
@@ -264,8 +268,10 @@ typedef enum {
 
 typedef enum {
     PROTOCOL_MOH_MIN = 6,
+    PROTOCOL_MOH_DEMO = 6,
     PROTOCOL_MOH = 8,
     PROTOCOL_MOHTA_MIN = 15,
+    PROTOCOL_MOHTA_DEMO = 16,
     PROTOCOL_MOHTA = 17,
 } protocol_e;
 

code/qcommon/qcommon.h

@@ -1056,6 +1056,10 @@ extern  cvar_t* con_autochat;
 #endif
 extern	cvar_t* com_target_version;
 extern	cvar_t* com_target_game;
+extern	cvar_t* com_target_demo;
+
+extern	int		protocol_version_demo;
+extern	int		protocol_version_full;
 
 // com_speeds times
 extern	int		time_game;

code/server/sv_client.c

@@ -284,6 +284,28 @@ challenge_t* FindChallenge(netadr_t from, qboolean connecting) {
 	return challenge;
 }
 
+/*
+==================
+SV_IsDemoClient
+
+Returns whether or not the client is using the demo version of the game
+==================
+*/
+
+qboolean SV_IsDemoClient(const char *userinfo)
+{
+	int version;
+
+	if (protocol_version_demo == protocol_version_full) {
+		// Older versions don't check for network demo
+		return qfalse;
+	}
+
+    version = atoi(Info_ValueForKey(userinfo, "protocol"));
+
+	return version == protocol_version_demo;
+}
+
 /*
 ==================
 SV_DirectConnect
@@ -338,6 +360,17 @@ void SV_DirectConnect( netadr_t from ) {
 
     version = atoi(Info_ValueForKey(userinfo, "protocol"));
 
+	if (!com_target_demo->integer && SV_IsDemoClient(userinfo)) {
+        SV_NET_OutOfBandPrint(&svs.netprofile, from, "print\nThe Multiplayer Demo can not connect to full version games.\n");
+		Com_DPrintf("    rejected connect from version %i\n", version);
+		return;
+    }
+
+    if (com_target_demo->integer && version == protocol_version_full) {
+		// Make sure to make the full game compatible with the demo game protocol
+        version = com_protocol->integer;
+    }
+	
 #ifdef LEGACY_PROTOCOL
 	if(version > 0 && com_legacyprotocol->integer == version)
 		compat = qtrue;

code/server/sv_main.c

@@ -615,8 +615,15 @@ void SVC_Info( netadr_t from ) {
 		Info_SetValueForKey( infostring, "game", gamedir );
 	}
 
+    if (!com_target_demo->integer || com_target_game->integer <= TG_MOH) {
         Info_SetValueForKey(infostring, "gamever", com_target_version->string);
+	} else {
+		Info_SetValueForKey(infostring, "gamever", va("d%s", com_target_version->string));
+	}
+
+	if (com_target_game->integer >= TG_MOHTT) {
 		Info_SetValueForKey(infostring, "serverType", va("%i", com_target_game->integer));
+	}
 
 	SV_NET_OutOfBandPrint( &svs.netprofile, from, "infoResponse\n%s", infostring );
 }

docs/getting_started_installation.md

@@ -14,7 +14,7 @@ Ensure that you download the binaries compatible with your platform in the [rele
 ## Requirements
 
 - A valid MOH:AA installation, a MOH:AA Warchest copy can be acquired from GOG [here](https://www.gog.com/en/game/medal_of_honor_allied_assault_war_chest).
-  - [Extracting GOG Installer on Linux and macOS](#extracting-gog-setup-file-on-linux-and-macos)
+  - [Extracting GOG Installer on Linux and macOS](#extracting-gog-setup-file-on-linux-and-macos). The demo version can also be used.
 - On Windows, Microsoft Visual C++ 2015/2017/2019/2022 Redistributable from https://learn.microsoft.com/en-US/cpp/windows/latest-supported-vc-redist?view=msvc-170 may be required.
 
 ## System requirements

docs/getting_started_running.md

@@ -19,6 +19,10 @@ On Windows, a shortcut can be created to the `openmohaa` executable, with the co
 
 You can now start a local OpenMOHAA server or play on a server.
 
+### Playing with the downloadable demo
+
+The argument `+set com_target_demo 1` must be appended to command-line to play the game/host a server using demo assets: Allied Assault, Spearhead and Breakthrough demo are supported.
+
 ### From the launchers
 
 For simplicity, there are 3 launchers for the standalone game: