introduce fractional framerates

#91

frontend/libretro.c

@@ -131,7 +131,8 @@ static unsigned previous_width = 0;
 static unsigned previous_height = 0;
 
 static int plugins_opened;
-static int is_pal_mode;
+
+#define is_pal_mode Config.PsxType
 
 /* memory card data */
 extern char Mcd1Data[MCD_SIZE];
@@ -586,7 +587,6 @@ void pl_frame_limit(void)
 
 void pl_timing_prepare(int is_pal)
 {
-   is_pal_mode = is_pal;
 }
 
 void plat_trigger_vibrate(int pad, int low, int high)
@@ -1002,7 +1002,7 @@ void retro_get_system_av_info(struct retro_system_av_info *info)
    unsigned geom_width           = vout_width;
 
    memset(info, 0, sizeof(*info));
-   info->timing.fps              = is_pal_mode ? 50.0 : 60.0;
+   info->timing.fps              = psxGetFps();
    info->timing.sample_rate      = 44100.0;
    info->geometry.base_width     = geom_width;
    info->geometry.base_height    = geom_height;
@@ -2265,6 +2265,7 @@ static void update_variables(bool in_flight)
    int gpu_peops_fix = GPU_PEOPS_OLD_FRAME_SKIP;
 #endif
    frameskip_type_t prev_frameskip_type;
+   double old_fps = psxGetFps();
 
    var.value = NULL;
    var.key = "pcsx_rearmed_frameskip_type";
@@ -2706,6 +2707,18 @@ static void update_variables(bool in_flight)
          Config.GpuListWalking = -1;
    }
 
+   var.value = NULL;
+   var.key = "pcsx_rearmed_fractional_framerate";
+   if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
+   {
+      if (strcmp(var.value, "disabled") == 0)
+         Config.FractionalFramerate = 0;
+      else if (strcmp(var.value, "enabled") == 0)
+         Config.FractionalFramerate = 1;
+      else // auto
+         Config.FractionalFramerate = -1;
+   }
+
    var.value = NULL;
    var.key = "pcsx_rearmed_screen_centering";
    if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE, &var) && var.value)
@@ -3005,6 +3018,13 @@ static void update_variables(bool in_flight)
    }
 
    update_option_visibility();
+
+   if (old_fps != psxGetFps())
+   {
+      struct retro_system_av_info info;
+      retro_get_system_av_info(&info);
+      environ_cb(RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO, &info);
+   }
 }
 
 // Taken from beetle-psx-libretro

frontend/libretro_core_options.h

@@ -425,6 +425,21 @@ struct retro_core_option_v2_definition option_defs_us[] = {
       },
       "disabled",
    },
+   {
+      "pcsx_rearmed_fractional_framerate",
+      "Use fractional frame rate",
+      NULL,
+      "Instead of the exact 50 or 60 (maximum) fps for PAL/NTSC the real console runs closer to something like 49.75 and 59.81fps (varies slightly between hw versions). PCSX-ReARMed uses the former \"round\" framerates to better match modern displays, however that may cause audio/video desync in games like DDR and Spyro 2 (intro). With this option you can try to use fractional framerates.",
+      NULL,
+      "video",
+      {
+         { "auto", "Auto" },
+         { "disabled", NULL },
+         { "enabled",  NULL },
+         { NULL, NULL },
+      },
+      "auto",
+   },
    {
       "pcsx_rearmed_gpu_slow_llists",
       "(GPU) Slow linked list processing",
@@ -433,7 +448,7 @@ struct retro_core_option_v2_definition option_defs_us[] = {
       NULL,
       "video",
       {
-         { "auto", NULL },
+         { "auto", "Auto" },
          { "disabled", NULL },
          { "enabled",  NULL },
          { NULL, NULL },

frontend/main.c

@@ -136,6 +136,7 @@ void emu_set_default_config(void)
 	Config.PsxAuto = 1;
 	Config.cycle_multiplier = CYCLE_MULT_DEFAULT;
 	Config.GpuListWalking = -1;
+	Config.FractionalFramerate = -1;
 
 	pl_rearmed_cbs.gpu_neon.allow_interlace = 2; // auto
 	pl_rearmed_cbs.gpu_neon.enhancement_enable =

frontend/menu.c

@@ -408,6 +408,7 @@ static const struct {
 	CE_CONFIG_VAL(DisableStalls),
 	CE_CONFIG_VAL(Cpu),
 	CE_CONFIG_VAL(GpuListWalking),
+	CE_CONFIG_VAL(FractionalFramerate),
 	CE_CONFIG_VAL(PreciseExceptions),
 	CE_INTVAL(region),
 	CE_INTVAL_V(g_scaler, 3),
@@ -1638,7 +1639,7 @@ static int menu_loop_speed_hacks(int id, int keys)
 	return 0;
 }
 
-static const char *men_gpul[]    = { "Auto", "Off", "On", NULL };
+static const char *men_autooo[]  = { "Auto", "Off", "On", NULL };
 
 static const char h_cfg_cpul[]   = "Shows CPU usage in %";
 static const char h_cfg_spu[]    = "Shows active SPU channels\n"
@@ -1657,10 +1658,12 @@ static const char h_cfg_exc[]    = "Emulate some PSX's debug hw like breakpoints
 				   "and exceptions (slow, interpreter only, keep off)";
 static const char h_cfg_gpul[]   = "Try enabling this if the game misses some graphics\n"
 				   "causes a performance hit";
+static const char h_cfg_ffps[]   = "Instead of 50/60fps for PAL/NTSC use ~49.75/59.81\n"
+				   "Closer to real hw but doesn't match modern displays.";
 static const char h_cfg_psxclk[]  = "Over/under-clock the PSX, default is " DEFAULT_PSX_CLOCK_S "\n"
 				    "(adjust this if the game is too slow/too fast/hangs)";
 
-enum { AMO_XA, AMO_CDDA, AMO_IC, AMO_BP, AMO_CPU, AMO_GPUL };
+enum { AMO_XA, AMO_CDDA, AMO_IC, AMO_BP, AMO_CPU, AMO_GPUL, AMO_FFPS };
 
 static menu_entry e_menu_adv_options[] =
 {
@@ -1671,7 +1674,8 @@ static menu_entry e_menu_adv_options[] =
 	mee_onoff_h   ("Disable CD Audio",       0, menu_iopts[AMO_CDDA], 1, h_cfg_cdda),
 	mee_onoff_h   ("ICache emulation",       0, menu_iopts[AMO_IC],   1, h_cfg_icache),
 	mee_onoff_h   ("BP exception emulation", 0, menu_iopts[AMO_BP],   1, h_cfg_exc),
-	mee_enum_h    ("GPU l-list slow walking",0, menu_iopts[AMO_GPUL], men_gpul, h_cfg_gpul),
+	mee_enum_h    ("GPU l-list slow walking",0, menu_iopts[AMO_GPUL], men_autooo, h_cfg_gpul),
+	mee_enum_h    ("Fractional framerate",   0, menu_iopts[AMO_FFPS], men_autooo, h_cfg_ffps),
 #if !defined(DRC_DISABLE) || defined(LIGHTREC)
 	mee_onoff_h   ("Disable dynarec (slow!)",0, menu_iopts[AMO_CPU],  1, h_cfg_nodrc),
 #endif
@@ -1697,12 +1701,14 @@ static int menu_loop_adv_options(int id, int keys)
 	for (i = 0; i < ARRAY_SIZE(opts); i++)
 		*opts[i].mopt = *opts[i].opt;
 	menu_iopts[AMO_GPUL] = Config.GpuListWalking + 1;
+	menu_iopts[AMO_FFPS] = Config.FractionalFramerate + 1;
 
 	me_loop(e_menu_adv_options, &sel);
 
 	for (i = 0; i < ARRAY_SIZE(opts); i++)
 		*opts[i].opt = *opts[i].mopt;
 	Config.GpuListWalking = menu_iopts[AMO_GPUL] - 1;
+	Config.FractionalFramerate = menu_iopts[AMO_FFPS] - 1;
 
 	return 0;
 }

frontend/plugin_lib.c

@@ -35,6 +35,7 @@
 #include "../libpcsxcore/psxmem_map.h"
 #include "../libpcsxcore/gpu.h"
 #include "../libpcsxcore/r3000a.h"
+#include "../libpcsxcore/psxcounters.h"
 
 #define HUD_HEIGHT 10
 
@@ -778,18 +779,20 @@ void pl_frame_limit(void)
 
 void pl_timing_prepare(int is_pal_)
 {
+	double fps;
 	pl_rearmed_cbs.fskip_advice = 0;
 	pl_rearmed_cbs.flips_per_sec = 0;
 	pl_rearmed_cbs.cpu_usage = 0;
 
 	is_pal = is_pal_;
-	frame_interval = is_pal ? 20000 : 16667;
-	frame_interval1024 = is_pal ? 20000*1024 : 17066667;
+	fps = psxGetFps();
+	frame_interval = (int)(1000000.0 / fps);
+	frame_interval1024 = (int)(1000000.0 * 1024.0 / fps);
 
 	// used by P.E.Op.S. frameskip code
-	pl_rearmed_cbs.gpu_peops.fFrameRateHz = is_pal ? 50.0f : 59.94f;
+	pl_rearmed_cbs.gpu_peops.fFrameRateHz = (float)fps;
 	pl_rearmed_cbs.gpu_peops.dwFrameRateTicks =
-		(100000*100 / (unsigned long)(pl_rearmed_cbs.gpu_peops.fFrameRateHz*100));
+		(100000*100 / (int)(pl_rearmed_cbs.gpu_peops.fFrameRateHz*100));
 }
 
 static void pl_get_layer_pos(int *x, int *y, int *w, int *h)

libpcsxcore/cdrom.c

@@ -583,19 +583,15 @@ static int cdrSeekTime(unsigned char *target)
 	int cyclesSinceRS = psxRegs.cycle - cdr.LastReadSeekCycles;
 	seekTime = MAX_VALUE(seekTime, 20000);
 
-	// need this stupidly long penalty or else Spyro2 intro desyncs
-	// note: if misapplied this breaks MGS cutscenes among other things
-	if (cdr.DriveState == DRIVESTATE_PAUSED && cyclesSinceRS > cdReadTime * 50)
-		seekTime += cdReadTime * 25;
 	// Transformers Beast Wars Transmetals does Setloc(x),SeekL,Setloc(x),ReadN
 	// and then wants some slack time
-	else if (cdr.DriveState == DRIVESTATE_PAUSED || cyclesSinceRS < cdReadTime *3/2)
+	if (cdr.DriveState == DRIVESTATE_PAUSED || cyclesSinceRS < cdReadTime *3/2)
 		seekTime += cdReadTime;
 
 	seekTime = MIN_VALUE(seekTime, PSXCLK * 2 / 3);
-	CDR_LOG("seek: %.2f %.2f (%.2f) st %d\n", (float)seekTime / PSXCLK,
+	CDR_LOG("seek: %.2f %.2f (%.2f) st %d di %d\n", (float)seekTime / PSXCLK,
 		(float)seekTime / cdReadTime, (float)cyclesSinceRS / cdReadTime,
-		cdr.DriveState);
+		cdr.DriveState, diff);
 	return seekTime;
 }
 

libpcsxcore/database.c

@@ -59,6 +59,22 @@ static const char * const dualshock_init_analog_hack_db[] =
 	"SLUS00546",
 };
 
+static const char * const fractional_Framerate_hack_db[] =
+{
+	/* Dance Dance Revolution */
+	"SLPM86503", // 3rd Mix
+	"SLPM86752", // 4th Mix
+	"SLPM86266", // 4thMix: The Beat Goes On
+	"SLPM86831", // Extra Mix
+	"SLUS01446", // Konamix
+	/* Dancing Stage Fever */
+	"SLES04097",
+	/* Dancing Stage Fusion */
+	"SLES04163",
+	/* Spyro 2 */
+	"SCUS94425", "SCES02104",
+};
+
 #define HACK_ENTRY(var, list) \
 	{ #var, &Config.hacks.var, list, ARRAY_SIZE(list) }
 
@@ -76,6 +92,7 @@ hack_db[] =
 	HACK_ENTRY(gpu_centering, gpu_centering_hack_db),
 	HACK_ENTRY(gpu_timing1024, dualshock_timing1024_hack_db),
 	HACK_ENTRY(dualshock_init_analog, dualshock_init_analog_hack_db),
+	HACK_ENTRY(fractional_Framerate, fractional_Framerate_hack_db),
 };
 
 static const struct

libpcsxcore/psxcommon.h

@@ -142,9 +142,10 @@ typedef struct {
 	boolean icache_emulation;
 	boolean DisableStalls;
 	boolean PreciseExceptions;
-	int GpuListWalking;
 	int cycle_multiplier; // 100 for 1.0
 	int cycle_multiplier_override;
+	s8 GpuListWalking;
+	s8 FractionalFramerate; // ~49.75 and ~59.81 instead of 50 and 60
 	u8 Cpu; // CPU_DYNAREC or CPU_INTERPRETER
 	u8 PsxType; // PSX_TYPE_NTSC or PSX_TYPE_PAL
 	struct {
@@ -153,6 +154,7 @@ typedef struct {
 		boolean gpu_centering;
 		boolean dualshock_init_analog;
 		boolean gpu_timing1024;
+		boolean fractional_Framerate;
 	} hacks;
 } PcsxConfig;
 

libpcsxcore/psxcounters.c

@@ -79,9 +79,40 @@ u32 psxNextCounter = 0, psxNextsCounter = 0;
 
 /******************************************************************************/
 
+#define FPS_FRACTIONAL_PAL  (53203425/314./3406) // ~49.75
+#define FPS_FRACTIONAL_NTSC (53693175/263./3413) // ~59.81
+
+static inline
+u32 frameCycles(void)
+{
+    int ff = Config.FractionalFramerate >= 0
+        ? Config.FractionalFramerate : Config.hacks.fractional_Framerate;
+    if (ff)
+    {
+        if (Config.PsxType)
+            return (u32)(PSXCLK / FPS_FRACTIONAL_PAL);
+        else
+            return (u32)(PSXCLK / FPS_FRACTIONAL_NTSC);
+    }
+    return Config.PsxType ? (PSXCLK / 50) : (PSXCLK / 60);
+}
+
+// used to inform the frontend about the exact framerate
+double psxGetFps()
+{
+    int ff = Config.FractionalFramerate >= 0
+        ? Config.FractionalFramerate : Config.hacks.fractional_Framerate;
+    if (ff)
+        return Config.PsxType ? FPS_FRACTIONAL_PAL : FPS_FRACTIONAL_NTSC;
+    else
+        return Config.PsxType ? 50.0 : 60.0;
+}
+
+// to inform the frontend about the exact famerate
 static inline
 u32 lineCycles(void)
 {
+    // should be more like above, but our timing is already poor anyway
     if (Config.PsxType)
         return PSXCLK / 50 / HSyncTotal[1];
     else
@@ -308,7 +339,7 @@ static void scheduleRcntBase(void)
 
     if (hSyncCount + hsync_steps == HSyncTotal[Config.PsxType])
     {
-        rcnts[3].cycle = Config.PsxType ? PSXCLK / 50 : PSXCLK / 60;
+        rcnts[3].cycle = frameCycles();
     }
     else
     {
@@ -380,7 +411,7 @@ void psxRcntUpdate()
         if( hSyncCount >= HSyncTotal[Config.PsxType] )
         {
             u32 status, field = 0;
-            rcnts[3].cycleStart += Config.PsxType ? PSXCLK / 50 : PSXCLK / 60;
+            rcnts[3].cycleStart += frameCycles();
             hSyncCount = 0;
             frame_counter++;
 

libpcsxcore/psxcounters.h

@@ -56,6 +56,8 @@ u32 psxRcntRtarget(u32 index);
 
 s32 psxRcntFreeze(void *f, s32 Mode);
 
+double psxGetFps();
+
 #ifdef __cplusplus
 }
 #endif

plugins/dfsound/externals.h

@@ -58,7 +58,7 @@
 #define MAXCHAN     24
 
 // note: must be even due to the way reverb works now
-#define NSSIZE ((44100 / 50 + 16) & ~1)
+#define NSSIZE ((44100 / 50 + 32) & ~1)
 
 ///////////////////////////////////////////////////////////
 // struct defines