From 808e450ed34f3f082efd7b5bd31e331f151fe683 Mon Sep 17 00:00:00 2001
From: Lephenixnoir <sebastien.michelland@protonmail.com>
Date: Mon, 13 Sep 2021 20:17:57 +0200
Subject: [PATCH] Enable demos (but they don't match the version)

---
 cgdoom/d_main.c   |  9 +++++---
 cgdoom/doomdef.h  |  2 +-
 cgdoom/doomstat.h |  6 +++---
 cgdoom/g_game.c   | 52 ++++++++++++++++++++++++++++++++++++++++++-----
 cgdoom/st_stuff.c |  4 ++--
 5 files changed, 59 insertions(+), 14 deletions(-)

diff --git a/cgdoom/d_main.c b/cgdoom/d_main.c
index 5616c8a..6d84c6a 100644
--- a/cgdoom/d_main.c
+++ b/cgdoom/d_main.c
@@ -343,9 +343,9 @@ void D_DoAdvanceDemo (void)
     gameaction = ga_nothing;
 
     if ( gamemode == retail )
-      demosequence = (demosequence+1)%3;
+      demosequence = (demosequence+1)%4;
     else
-      demosequence = (demosequence+1)%2;
+      demosequence = (demosequence+1)%3;
 
     switch (demosequence)
     {
@@ -358,11 +358,14 @@ void D_DoAdvanceDemo (void)
         pagename = "TITLEPIC";
         break;
       case 1:
+        G_DeferedPlayDemo ("demo1");
+        break;
+      case 2:
         pagetic = 200;
         gamestate = GS_DEMOSCREEN;
         pagename = "CREDIT";
         break;
-      case 2:
+      case 3:
         gamestate = GS_DEMOSCREEN;
         if ( gamemode == commercial)
         {
diff --git a/cgdoom/doomdef.h b/cgdoom/doomdef.h
index 1967f0f..adb37f6 100644
--- a/cgdoom/doomdef.h
+++ b/cgdoom/doomdef.h
@@ -31,7 +31,7 @@
 // Global parameters/defines.
 //
 // DOOM version
-#define VERSION 110;
+#define VERSION 110
 
 
 // Game mode handling - identify IWAD version
diff --git a/cgdoom/doomstat.h b/cgdoom/doomstat.h
index f2a520e..eaf214f 100644
--- a/cgdoom/doomstat.h
+++ b/cgdoom/doomstat.h
@@ -81,7 +81,7 @@ extern  int		gamemap;
 extern  boolean         respawnmonsters;
 
 // Netgame? Only true if >1 player.
-extern  const boolean	netgame;
+extern  boolean	netgame;
 
 // Flag: true only if started as net deathmatch.
 // An enum might handle altdeath/cooperative better.
@@ -147,7 +147,7 @@ extern	int		scaledviewwidth;
 extern  int	viewangleoffset;
 
 // Player taking events, and displaying.
-extern  const int	consoleplayer;	
+extern  int	consoleplayer;
 extern  int	displayplayer;
 
 
@@ -234,7 +234,7 @@ extern  const int					maxammo[NUMAMMO];
 //extern  FILE*				debugfile;
 
 // if true, load all graphics at level load
-extern  const boolean				precache;
+extern  boolean				precache;
 
 
 // wipegamestate can be set to -1
diff --git a/cgdoom/g_game.c b/cgdoom/g_game.c
index dd4fff9..ed3b253 100644
--- a/cgdoom/g_game.c
+++ b/cgdoom/g_game.c
@@ -82,6 +82,7 @@ void     G_DoReborn (void);
 void     G_DoLoadLevel (void); 
 void     G_DoNewGame (void); 
 void     G_DoLoadGame (void); 
+void     G_DoPlayDemo (void);
 void     G_DoCompleted (void); 
 void     G_DoVictory (void); 
 void     G_DoWorldDone (void); 
@@ -108,24 +109,25 @@ int      starttime;           // for comparative timing purposes
 boolean     viewactive; 
 
 boolean     deathmatch;            // only if started as net death 
-const boolean     netgame = 0;                // only true if packets are broadcast 
+boolean     netgame = 0;                // only true if packets are broadcast
 boolean     playeringame[MAXPLAYERS]; 
 player_t    players[MAXPLAYERS]; 
 
-const      int consoleplayer = 0;          // player taking events and displaying 
+int consoleplayer = 0;          // player taking events and displaying
 int      displayplayer;          // view being displayed 
 int                gametic; 
 int               levelstarttic;          // gametic at level start 
 int               totalkills, totalitems, totalsecret;    // for intermission 
 
 //char     demoname[32]; 
-const boolean     netdemo = 0; 
+boolean         demoplayback;
+boolean     netdemo = 0;
 byte*     demobuffer;
 byte*     demo_p;
 byte*     demoend; 
 boolean           singledemo;             // quit after playing a demo from cmdline 
 
-const boolean          precache = false;        // if true, load all graphics at start 
+boolean          precache = false;        // if true, load all graphics at start
 
 wbstartstruct_t   wminfo;                // parms for world map / intermission 
 
@@ -459,7 +461,7 @@ void G_Ticker (void)
       G_DoSaveGame (); 
       break; 
     case ga_playdemo:
-      /* CGDoom: Main menu demo is disabled (code removed) */
+      G_DoPlayDemo ();
       break;
     case ga_completed: 
       G_DoCompleted (); 
@@ -1127,6 +1129,46 @@ void G_DeferedPlayDemo (char* name)
   gameaction = ga_playdemo; 
 } 
 
+void G_DoPlayDemo (void)
+{
+  skill_t skill;
+  int i, episode, map;
+
+  gameaction = ga_nothing;
+  demobuffer = demo_p = (byte *)W_CacheLumpNameConst (defdemoname, PU_STATIC);
+  if ( *demo_p++ != VERSION)
+  {
+    // fprintf( stderr, "Demo is from a different game version!\n");
+    gameaction = ga_nothing;
+    return;
+  }
+
+  skill = *demo_p++;
+  episode = *demo_p++;
+  map = *demo_p++;
+  deathmatch = *demo_p++;
+  respawnparm = *demo_p++;
+  fastparm = *demo_p++;
+  nomonsters = *demo_p++;
+  consoleplayer = *demo_p++;
+
+  for (i=0 ; i<MAXPLAYERS ; i++)
+    playeringame[i] = *demo_p++;
+  if (playeringame[1])
+  {
+    netgame = true;
+    netdemo = true;
+  }
+
+  // don't spend a lot of time in loadlevel
+  precache = false;
+  G_InitNew (skill, episode, map);
+  precache = true;
+
+  usergame = false;
+  demoplayback = true;
+}
+
 //
 // G_TimeDemo 
 //
diff --git a/cgdoom/st_stuff.c b/cgdoom/st_stuff.c
index 052a3ed..f426c35 100644
--- a/cgdoom/st_stuff.c
+++ b/cgdoom/st_stuff.c
@@ -818,8 +818,8 @@ void ST_doPaletteStuff(void)
     // slowly fade the berzerk out
     bzc = 12 - (plyr->powers[pw_strength]>>6);
 
-  if (bzc > cnt)
-    cnt = bzc;
+    if (bzc > cnt)
+      cnt = bzc;
   }
 
   if (cnt)