Add adjustable FOV (#1364)

* Add adjustable FOV

* Always use custom FOV when non-zero

* Fix pixels at edge of screen for 32:9 aspect ratio

* Remove in-game aspect ratio selection for now

* Revert "Fix pixels at edge of screen for 32:9 aspect ratio"

This reverts commit ab1df333f610f4097bca0256694b3c99f69eb9de.

src/doomdef.h

@@ -80,6 +80,7 @@ typedef enum
 #define SCREENWIDTH  320
 #define SCREENHEIGHT 200
 #define NONWIDEWIDTH SCREENWIDTH // [crispy] non-widescreen SCREENWIDTH
+#define ACTUALHEIGHT 240
 
 // The maximum number of players, multiplayer/networking.
 #define MAXPLAYERS       4

src/i_video.c

@@ -44,8 +44,6 @@
 
 #include "icon.c"
 
-#define ACTUALHEIGHT 240
-
 resolution_mode_t resolution_mode, default_resolution_mode;
 
 boolean use_vsync;  // killough 2/8/98: controls whether vsync is called
@@ -55,6 +53,7 @@ int fpslimit; // when uncapped, limit framerate to this value
 boolean fullscreen;
 boolean exclusive_fullscreen;
 aspect_ratio_mode_t widescreen, default_widescreen; // widescreen mode
+int custom_fov;
 boolean vga_porch_flash; // emulate VGA "porch" behaviour
 boolean smooth_scaling;
 
@@ -989,7 +988,7 @@ static double CurrentAspectRatio(void)
             w = SCREENWIDTH;
             h = unscaled_actualheight;
             break;
-        case RATIO_MATCH_SCREEN:
+        case RATIO_AUTO:
             w = native_width;
             h = native_height;
             break;
@@ -1005,6 +1004,10 @@ static double CurrentAspectRatio(void)
             w = 21;
             h = 9;
             break;
+        case RATIO_32_9:
+            w = 32;
+            h = 9;
+            break;
         default:
             w = 16;
             h = 9;
@@ -1013,14 +1016,51 @@ static double CurrentAspectRatio(void)
 
     double aspect_ratio = (double)w / (double)h;
 
-    if (aspect_ratio > 2.4)
+    if (aspect_ratio > ASPECT_RATIO_MAX)
     {
-        aspect_ratio = 2.4;
+        aspect_ratio = ASPECT_RATIO_MAX;
     }
 
     return aspect_ratio;
 }
 
+// Fineangles in the SCREENWIDTH wide window.
+#define FIELDOFVIEW 2048
+
+void I_UpdateFOV(void)
+{
+    if (custom_fov)
+    {
+        const double slope = tan(custom_fov * M_PI / 360);
+        const double dist = (CurrentAspectRatio() * ACTUALHEIGHT / 2) / slope;
+
+        video.fov = custom_fov * ANG1;
+        pov_slope = slope * FRACUNIT;
+        pov_distance = dist * FRACUNIT;
+        lookdirmax = lround(dist * 100 / 160);
+    }
+    else
+    {
+        if (widescreen == RATIO_ORIG)
+        {
+            video.fov = ANG90;
+            pov_slope = finetangent[FINEANGLES / 4 + FIELDOFVIEW / 2];
+        }
+        else
+        {
+            const double slope = CurrentAspectRatio() * 3 / 4;
+
+            video.fov = 2 * atan(slope) / M_PI * ANG180;
+            pov_slope = slope * FRACUNIT;
+        }
+
+        pov_distance = (SCREENWIDTH / 2) << FRACBITS;
+        lookdirmax = 100;
+    }
+
+    lookdirs = 2 * lookdirmax + 1;
+}
+
 static void ResetResolution(int height)
 {
     double aspect_ratio = CurrentAspectRatio();
@@ -1044,7 +1084,7 @@ static void ResetResolution(int height)
 
     video.deltaw = (video.unscaledw - NONWIDEWIDTH) / 2;
 
-    video.fov = 2 * atan(video.unscaledw / (1.2 * SCREENHEIGHT) * 3 / 4) / M_PI * ANG180;
+    I_UpdateFOV();
 
     Z_FreeTag(PU_VALLOC);
 
@@ -1495,7 +1535,7 @@ static void CreateSurfaces(void)
                                 SDL_TEXTUREACCESS_STREAMING,
                                 w, h);
 
-    widescreen = RATIO_MATCH_SCREEN;
+    widescreen = RATIO_AUTO;
 
     ResetResolution(h);
     R_InitAnyRes();
@@ -1503,7 +1543,7 @@ static void CreateSurfaces(void)
 
     widescreen = default_widescreen;
 
-    if (resolution_mode != RES_DRS || widescreen != RATIO_MATCH_SCREEN)
+    if (resolution_mode != RES_DRS || widescreen != RATIO_AUTO)
     {
         ResetResolution(CurrentResolutionMode());
     }

src/i_video.h

@@ -24,13 +24,18 @@
 
 #include "doomtype.h"
 
+#define FOVMIN 40
+#define FOVMAX 140 // Up to 32:9 ultrawide.
+#define ASPECT_RATIO_MAX 3.6 // Up to 32:9 ultrawide.
+
 typedef enum
 {
     RATIO_ORIG,
-    RATIO_MATCH_SCREEN,
+    RATIO_AUTO,
     RATIO_16_10,
     RATIO_16_9,
     RATIO_21_9,
+    RATIO_32_9,
     NUM_RATIOS
 } aspect_ratio_mode_t;
 
@@ -61,6 +66,7 @@ void I_FinishUpdate(void);
 
 void I_ReadScreen(byte* dst);
 
+void I_UpdateFOV(void);
 void I_ResetScreen(void);   // killough 10/98
 void I_ResetTargetRefresh(void);
 void I_ToggleVsync(void); // [JN] Calls native SDL vsync toggle
@@ -82,6 +88,7 @@ extern int fpslimit; // when uncapped, limit framerate to this value
 extern int fps;
 extern boolean vga_porch_flash; // emulate VGA "porch" behaviour
 extern aspect_ratio_mode_t widescreen, default_widescreen; // widescreen mode
+extern int custom_fov; // Custom FOV set by the player.
 extern int video_display; // display index
 extern boolean screenvisible;
 extern boolean window_focused;

src/m_menu.c

@@ -3638,6 +3638,7 @@ enum {
   gen1_title1,
   gen1_hires,
   gen1_widescreen,
+  gen1_fov,
   gen1_gap1,
 
   gen1_fullscreen,
@@ -3777,6 +3778,17 @@ static void M_CoerceFPSLimit(void)
   I_ResetTargetRefresh();
 }
 
+static void M_UpdateFOV(void)
+{
+  if (custom_fov < FOVMIN)
+  {
+    custom_fov = 0;
+  }
+
+  I_UpdateFOV();
+  R_ExecuteSetViewSize();
+}
+
 static void M_ResetScreen(void)
 {
   need_reset = true;
@@ -3792,6 +3804,9 @@ setup_menu_t gen_settings1[] = { // General Settings screen1
   {"Widescreen Rendering", S_YESNO, m_null, M_X, M_Y+ gen1_widescreen*M_SPC,
    {"widescreen"}, 0, M_ResetScreen},
 
+  {"FOV", S_NUM, m_null, M_X, M_Y + gen1_fov*M_SPC,
+   {"fov"}, 0, M_UpdateFOV},
+
   {"", S_SKIP, m_null, M_X, M_Y + gen1_gap1*M_SPC},
 
   {"Fullscreen Mode", S_YESNO, m_null, M_X, M_Y+ gen1_fullscreen*M_SPC,

src/m_misc.c

@@ -205,8 +205,15 @@ default_t defaults[] = {
   {
     "widescreen",
     (config_t *) &default_widescreen, NULL,
-    {RATIO_MATCH_SCREEN}, {RATIO_ORIG, NUM_RATIOS-1}, number, ss_none, wad_no,
+    {RATIO_AUTO}, {RATIO_ORIG, NUM_RATIOS-1}, number, ss_none, wad_no,
-    "widescreen mode (0 = disable, 1 = match screen, 2 = 16:10, 3 = 16:9, 4 = 21:9)"
+    "Widescreen (0 = Off, 1 = Auto, 2 = 16:10, 3 = 16:9, 4 = 21:9, 5 = 32:9)"
+  },
+
+  {
+    "fov",
+    (config_t *) &custom_fov, NULL,
+    {0}, {0, FOVMAX}, number, ss_none, wad_no,
+    "Field of view in degrees (0 = Auto, 40 to 140 = Custom)"
   },
 
   // display index

src/p_mobj.h

@@ -425,7 +425,7 @@ extern boolean colored_blood;
 // Heretic/Hexen used value `173` presumably because Raven assumed an
 // equilateral triangle (i.e. 60°) for the vertical FOV which spans
 // 200 px, so the height of that triangle would be 100*sqrt(3) = 173.
-#define PLAYER_SLOPE(a)	((((a)->lookdir / MLOOKUNIT) << FRACBITS) / 160)
+#define PLAYER_SLOPE(a)	(FixedDiv(((a)->lookdir << FRACBITS) / MLOOKUNIT, pov_distance))
 extern boolean direct_vertical_aiming, default_direct_vertical_aiming;
 void P_UpdateDirectVerticalAiming(void);
 

src/p_user.c

@@ -238,8 +238,8 @@ void P_MovePlayer (player_t* player)
 
   if (!menuactive && !demoplayback)
   {
-    player->lookdir = BETWEEN(-LOOKDIRMAX * MLOOKUNIT,
+    player->lookdir = BETWEEN(-lookdirmax * MLOOKUNIT,
-                               LOOKDIRMAX * MLOOKUNIT,
+                               lookdirmax * MLOOKUNIT,
                                player->lookdir + cmd->lookdir);
     player->slope = PLAYER_SLOPE(player);
   }

src/r_data.h

@@ -24,8 +24,9 @@
 #include "r_defs.h"
 #include "r_state.h"
 
-#define LOOKDIRMAX	100
+// Largest range at FOV 40, AR 3.6 (742 = (3.6*240/2)/tan(40*M_PI/360)*100/160).
-#define LOOKDIRS	(2*LOOKDIRMAX+1) // [crispy] lookdir range: -100..100
+#define LOOKDIRSMAX (2 * 742 + 1)
+
 #define MLOOKUNIT	8
 
 // Retrieve column data for span blitting.

src/r_main.c

@@ -32,9 +32,6 @@
 #include "am_map.h"
 #include "st_stuff.h"
 
-// Fineangles in the SCREENWIDTH wide window.
-#define FIELDOFVIEW 2048    
-
 // killough: viewangleoffset is a legacy from the pre-v1.2 days, when Doom
 // had Left/Mid/Right viewing. +/-ANG90 offsets were placed here on each
 // node, by d_net.c, to set up a L/M/R session.
@@ -53,6 +50,10 @@ fixed_t  viewcos, viewsin;
 player_t *viewplayer;
 extern lighttable_t **walllights;
 fixed_t  viewheightfrac; // [FG] sprite clipping optimizations
+fixed_t pov_slope;
+fixed_t pov_distance;
+int lookdirmax;
+int lookdirs;
 
 //
 // precalculated math tables
@@ -251,11 +252,10 @@ static fixed_t centerxfrac_nonwide;
 //
 // killough 5/2/98: reformatted
 
-static void R_InitTextureMapping (void)
+static void R_InitTextureMapping(fixed_t focallength)
 {
   register int i,x;
-  fixed_t focallength;
+
-    
   // Use tangent table to generate viewangletox:
   //  viewangletox will give the next greatest x
   //  after the view angle.
@@ -263,15 +263,13 @@ static void R_InitTextureMapping (void)
   // Calc focallength
   //  so FIELDOFVIEW angles covers SCREENWIDTH.
 
-  focallength = FixedDiv(centerxfrac_nonwide, finetangent[FINEANGLES/4+FIELDOFVIEW/2]);
-        
   for (i=0 ; i<FINEANGLES/2 ; i++)
     {
       int t;
-      if (finetangent[i] > FRACUNIT*2)
+      if (finetangent[i] > pov_slope)
         t = -1;
       else
-        if (finetangent[i] < -FRACUNIT*2)
+        if (finetangent[i] < -pov_slope)
           t = viewwidth+1;
       else
         {
@@ -502,12 +500,12 @@ void R_ExecuteSetViewSize (void)
   centerxfrac = centerx<<FRACBITS;
   centeryfrac = centery<<FRACBITS;
   centerxfrac_nonwide = (viewwidth_nonwide/2)<<FRACBITS;
-  projection = centerxfrac_nonwide;
+  projection = FixedDiv(centerxfrac, pov_slope);
   viewheightfrac = viewheight<<(FRACBITS+1); // [FG] sprite clipping optimizations
 
   R_InitBuffer();       // killough 11/98
         
-  R_InitTextureMapping();
+  R_InitTextureMapping(projection);
     
   // psprite scales
   pspritescale = FixedDiv(viewwidth_nonwide, SCREENWIDTH);       // killough 11/98
@@ -520,14 +518,14 @@ void R_ExecuteSetViewSize (void)
   // planes
   for (i=0 ; i<viewheight ; i++)
     {   // killough 5/2/98: reformatted
-      for (j = 0; j < LOOKDIRS; j++)
+      for (j = 0; j < lookdirs; j++)
       {
         // [crispy] re-generate lookup-table for yslope[] whenever "viewheight" or "hires" change
-        fixed_t dy = abs(((i-viewheight/2-(j-LOOKDIRMAX)*viewblocks/10)<<FRACBITS)+FRACUNIT/2);
+        fixed_t dy = abs(((i-viewheight/2-(j-lookdirmax)*viewblocks/10)<<FRACBITS)+FRACUNIT/2);
-        yslopes[j][i] = FixedDiv(viewwidth_nonwide*(FRACUNIT/2), dy);
+        yslopes[j][i] = FixedDiv(projection, dy);
       }
     }
-  yslope = yslopes[LOOKDIRMAX];
+  yslope = yslopes[lookdirmax];
         
   for (i=0 ; i<viewwidth ; i++)
     {
@@ -698,11 +696,11 @@ void R_SetupFrame (player_t *player)
 
   extralight = player->extralight;
   extralight += STRICTMODE(LIGHTBRIGHT * extra_level_brightness);
-    
+
-  if (pitch > LOOKDIRMAX)
+  if (pitch > lookdirmax)
-    pitch = LOOKDIRMAX;
+    pitch = lookdirmax;
-  else if (pitch < -LOOKDIRMAX)
+  else if (pitch < -lookdirmax)
-    pitch = -LOOKDIRMAX;
+    pitch = -lookdirmax;
 
   // apply new yslope[] whenever "lookdir", "viewheight" or "hires" change
   tempCentery = viewheight/2 + pitch * viewblocks / 10;
@@ -710,7 +708,7 @@ void R_SetupFrame (player_t *player)
   {
       centery = tempCentery;
       centeryfrac = centery << FRACBITS;
-      yslope = yslopes[LOOKDIRMAX + pitch];
+      yslope = yslopes[lookdirmax + pitch];
   }
 
   viewsin = finesine[viewangle>>ANGLETOFINESHIFT];

src/r_main.h

@@ -40,6 +40,10 @@ extern int      validcount;
 extern int      linecount;
 extern int      loopcount;
 extern fixed_t  viewheightfrac; // [FG] sprite clipping optimizations
+extern fixed_t  pov_slope; // For calculating projection.
+extern fixed_t  pov_distance; // Distance from POV to projection plane.
+extern int      lookdirmax;
+extern int      lookdirs;
 
 //
 // Rendering stats

src/r_plane.c

@@ -119,7 +119,7 @@ void R_InitPlanesRes(void)
 
   if (yslopes)
   {
-    for (i = 0; i < LOOKDIRS; ++i)
+    for (i = 0; i < LOOKDIRSMAX; ++i)
     {
       Z_Free(yslopes[i]);
     }
@@ -136,8 +136,8 @@ void R_InitPlanesRes(void)
   cachedxstep = Z_Calloc(1, video.height * sizeof(*cachedxstep), PU_STATIC, NULL);
   cachedystep = Z_Calloc(1, video.height * sizeof(*cachedystep), PU_STATIC, NULL);
 
-  yslopes = Z_Malloc(LOOKDIRS * sizeof(*yslopes), PU_STATIC, NULL);
+  yslopes = Z_Malloc(LOOKDIRSMAX * sizeof(*yslopes), PU_STATIC, NULL);
-  for (i = 0; i < LOOKDIRS; ++i)
+  for (i = 0; i < LOOKDIRSMAX; ++i)
   {
     yslopes[i] = Z_Calloc(1, video.height * sizeof(**yslopes), PU_STATIC, NULL);
   }

src/v_video.c

@@ -284,7 +284,7 @@ void WriteGeneratedLumpWad(const char *filename)
 
 video_t video;
 
-#define WIDE_SCREENWIDTH 576 // corresponds to 2.4 aspect ratio
+#define WIDE_SCREENWIDTH 864 // corresponds to 3.6 aspect ratio
 
 static int x1lookup[WIDE_SCREENWIDTH + 1];
 static int y1lookup[SCREENHEIGHT + 1];