From a5da1900d0c4991827a210b126bd9ee667b5e088 Mon Sep 17 00:00:00 2001
From: Fabian Greffrath <fabian@greffrath.com>
Date: Tue, 14 Apr 2020 11:31:11 +0200
Subject: [PATCH] add an FPS counter widget

and the SHOWFPS cheat to enable it (only if not in automap)
---
 Source/d_player.h |  4 +++-
 Source/hu_stuff.c | 22 ++++++++++++++++++++++
 Source/i_video.c  | 22 ++++++++++++++++++++++
 Source/m_cheat.c  | 11 +++++++++++
 4 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/Source/d_player.h b/Source/d_player.h
index de1222b8..1a766fa4 100644
--- a/Source/d_player.h
+++ b/Source/d_player.h
@@ -70,7 +70,9 @@ typedef enum
   // No damage, no health loss.
   CF_GODMODE          = 2,
   // Not really a cheat, just a debug aid.
-  CF_NOMOMENTUM       = 4
+  CF_NOMOMENTUM       = 4,
+  // [FG] FPS counter widget
+  CF_SHOWFPS          = 8
 
 } cheat_t;
 
diff --git a/Source/hu_stuff.c b/Source/hu_stuff.c
index a1582a82..49afbba4 100644
--- a/Source/hu_stuff.c
+++ b/Source/hu_stuff.c
@@ -173,6 +173,7 @@ static hu_textline_t  w_keys;   //jff 2/16/98 new keys widget for hud
 static hu_textline_t  w_gkeys;  //jff 3/7/98 graphic keys widget for hud
 static hu_textline_t  w_monsec; //jff 2/16/98 new kill/secret widget for hud
 static hu_mtext_t     w_rtext;  //jff 2/26/98 text message refresh widget
+static hu_textline_t  w_fps;    // [FG] FPS counter widget
 
 static boolean    always_off = false;
 static char       chat_dest[MAXPLAYERS];
@@ -222,6 +223,7 @@ static char hud_weapstr[80];
 static char hud_keysstr[80];
 static char hud_gkeysstr[80]; //jff 3/7/98 add support for graphic key display
 static char hud_monsecstr[80];
+static char hud_fpsstr[32]; // [FG] FPS counter widget
 
 //
 // Builtin map names.
@@ -527,6 +529,9 @@ void HU_Start(void)
 		     HU_FONTSTART, colrngs[hudcolor_xyco]);
   HUlib_initTextLine(&w_coordz, HU_COORDX, HU_COORDZ_Y, hu_font,
 		     HU_FONTSTART, colrngs[hudcolor_xyco]);
+  // [FG] FPS counter widget
+  HUlib_initTextLine(&w_fps, HU_COORDX, HU_COORDX_Y, hu_font,
+		     HU_FONTSTART, colrngs[hudcolor_xyco]);
   
   // initialize the automaps coordinate widget
   //jff 3/3/98 split coordstr widget into 3 parts
@@ -542,6 +547,11 @@ void HU_Start(void)
   s = hud_coordstrz;
   while (*s)
     HUlib_addCharToTextLine(&w_coordz, *s++);
+  // [FG] FPS counter widget
+  sprintf(hud_fpsstr,"%-5d FPS",0);
+  s = hud_fpsstr;
+  while (*s)
+    HUlib_addCharToTextLine(&w_fps, *s++);
 
   //jff 2/16/98 initialize ammo widget
   sprintf(hud_ammostr,"AMM ");
@@ -719,6 +729,18 @@ void HU_Drawer(void)
         HUlib_addCharToTextLine(&w_coordz, *s++);
       HUlib_drawTextLine(&w_coordz, false);
     }
+  // [FG] FPS counter widget
+  else if (plr->cheats & CF_SHOWFPS)
+    {
+      extern int fps;
+
+      sprintf(hud_fpsstr,"%-5d FPS", fps);  // killough 10/98
+      HUlib_clearTextLine(&w_fps);
+      s = hud_fpsstr;
+      while (*s)
+        HUlib_addCharToTextLine(&w_fps, *s++);
+      HUlib_drawTextLine(&w_fps, false);
+    }
 
   // draw the weapon/health/ammo/armor/kills/keys displays if optioned
   //jff 2/17/98 allow new hud stuff to be turned off
diff --git a/Source/i_video.c b/Source/i_video.c
index bd017b26..fbc9b504 100644
--- a/Source/i_video.c
+++ b/Source/i_video.c
@@ -682,6 +682,8 @@ static int in_page_flip, in_hires;
 static void I_DrawDiskIcon(), I_RestoreDiskBackground();
 static unsigned int disk_to_draw, disk_to_restore;
 
+int fps; // [FG] FPS counter widget
+
 void I_FinishUpdate(void)
 {
    if (noblit || !in_graphics_mode)
@@ -726,6 +728,26 @@ void I_FinishUpdate(void)
       }
    }
 
+   // [crispy] [AM] Real FPS counter
+   {
+      static int lastmili;
+      static int fpscount;
+      int i, mili;
+
+      fpscount++;
+
+      i = SDL_GetTicks();
+      mili = i - lastmili;
+
+      // Update FPS counter every second
+      if (mili >= 1000)
+      {
+         fps = (fpscount * 1000) / mili;
+         fpscount = 0;
+         lastmili = i;
+      }
+   }
+
    I_DrawDiskIcon();
 
    SDL_LowerBlit(sdlscreen, &blit_rect, argbbuffer, &blit_rect);
diff --git a/Source/m_cheat.c b/Source/m_cheat.c
index f88259a0..ba7cec2c 100644
--- a/Source/m_cheat.c
+++ b/Source/m_cheat.c
@@ -83,6 +83,7 @@ static void cheat_printstats();   // killough 8/23/98
 
 static void cheat_autoaim();      // killough 7/19/98
 static void cheat_tst();
+static void cheat_showfps(); // [FG] FPS counter widget
 
 //-----------------------------------------------------------------------------
 //
@@ -256,6 +257,10 @@ struct cheat_s cheat[] = {
    cheat_printstats},
 #endif
 
+// [FG] FPS counter widget
+  {"showfps",    NULL,                always,
+   cheat_showfps},
+
   {NULL}                 // end-of-list marker
 };
 
@@ -269,6 +274,12 @@ static void cheat_printstats()    // killough 8/23/98
 }
 #endif
 
+// [FG] FPS counter widget
+static void cheat_showfps()
+{
+  plyr->cheats ^= CF_SHOWFPS;
+}
+
 // killough 7/19/98: Autoaiming optional in beta emulation mode
 static void cheat_autoaim()
 {