Add optional frame skipping when fast-forwarding (#13550)

config.def.h

@@ -1253,6 +1253,9 @@ static const bool savestate_thumbnail_enable = false;
 /* Maximum fast forward ratio. */
 #define DEFAULT_FASTFORWARD_RATIO 0.0
 
+/* Skip frames when fast forwarding. */
+#define DEFAULT_FASTFORWARD_FRAMESKIP true
+
 /* Enable runloop for variable refresh rate screens. Force x1 speed while handling fast forward too. */
 #define DEFAULT_VRR_RUNLOOP_ENABLE false
 

configuration.c

@@ -1654,6 +1654,7 @@ static struct config_bool_setting *populate_settings_bool(
    SETTING_BOOL("ui_menubar_enable",             &settings->bools.ui_menubar_enable, true, DEFAULT_UI_MENUBAR_ENABLE, false);
    SETTING_BOOL("suspend_screensaver_enable",    &settings->bools.ui_suspend_screensaver_enable, true, true, false);
    SETTING_BOOL("rewind_enable",                 &settings->bools.rewind_enable, true, DEFAULT_REWIND_ENABLE, false);
+   SETTING_BOOL("fastforward_frameskip",         &settings->bools.fastforward_frameskip, true, DEFAULT_FASTFORWARD_FRAMESKIP, false);
    SETTING_BOOL("vrr_runloop_enable",            &settings->bools.vrr_runloop_enable, true, DEFAULT_VRR_RUNLOOP_ENABLE, false);
    SETTING_BOOL("apply_cheats_after_toggle",     &settings->bools.apply_cheats_after_toggle, true, DEFAULT_APPLY_CHEATS_AFTER_TOGGLE, false);
    SETTING_BOOL("apply_cheats_after_load",       &settings->bools.apply_cheats_after_load, true, DEFAULT_APPLY_CHEATS_AFTER_LOAD, false);

configuration.h

@@ -834,6 +834,7 @@ typedef struct settings
       bool history_list_enable;
       bool playlist_entry_rename;
       bool rewind_enable;
+      bool fastforward_frameskip;
       bool vrr_runloop_enable;
       bool apply_cheats_after_toggle;
       bool apply_cheats_after_load;

gfx/video_driver.c

@@ -3579,6 +3579,7 @@ void video_driver_frame(const void *data, unsigned width,
    const enum retro_pixel_format
       video_driver_pix_fmt       = video_st->pix_fmt;
    bool runloop_idle             = runloop_st->idle;
+   bool render_frame             = !runloop_st->fastforward_frameskip_frames_current;
    bool video_driver_active      = video_st->active;
 #if defined(HAVE_GFX_WIDGETS)
    bool widgets_active           = dispwidget_get_ptr()->active;
@@ -3617,6 +3618,11 @@ void video_driver_frame(const void *data, unsigned width,
 
    video_driver_build_info(&video_info);
 
+   render_frame |= video_info.menu_is_alive;
+
+   if (!render_frame)
+      runloop_st->fastforward_frameskip_frames_current--;
+
    /* Get the amount of frames per seconds. */
    if (video_st->frame_count)
    {
@@ -3772,7 +3778,7 @@ void video_driver_frame(const void *data, unsigned width,
             pitch, runloop_idle);
 
 #ifdef HAVE_VIDEO_FILTER
-   if (data && video_st->state_filter)
+   if (render_frame && data && video_st->state_filter)
    {
       unsigned output_width                             = 0;
       unsigned output_height                            = 0;
@@ -3834,11 +3840,7 @@ void video_driver_frame(const void *data, unsigned width,
                   msg_entry.category,
                   msg_entry.prio,
                   false,
-#ifdef HAVE_MENU
+                  video_info.menu_is_alive
-                  menu_state_get_ptr()->alive
-#else
-                  false
-#endif
             );
       }
       /* ...otherwise, just output message via
@@ -3858,7 +3860,7 @@ void video_driver_frame(const void *data, unsigned width,
       }
    }
 
-   if (video_info.statistics_show)
+   if (render_frame && video_info.statistics_show)
    {
       audio_statistics_t audio_stats;
       double stddev                          = 0.0;
@@ -3920,13 +3922,17 @@ void video_driver_frame(const void *data, unsigned width,
       /* TODO/FIXME - add OSD chat text here */
    }
 
-   if (video_st->current_video && video_st->current_video->frame)
+   if (render_frame && video_st->current_video && video_st->current_video->frame)
+   {
       video_st->active = video_st->current_video->frame(
             video_st->data, data, width, height,
             video_st->frame_count, (unsigned)pitch,
             video_info.menu_screensaver_active || video_info.notifications_hidden ? "" : video_driver_msg,
             &video_info);
 
+      runloop_st->fastforward_frameskip_frames_current = runloop_st->fastforward_frameskip_frames;
+   }
+
    video_st->frame_count++;
 
    /* Display the status text, with a higher priority. */

intl/msg_hash_lbl.h

@@ -1234,6 +1234,10 @@ MSG_HASH(
    MENU_ENUM_LABEL_FASTFORWARD_RATIO,
    "fastforward_ratio"
    )
+MSG_HASH(
+   MENU_ENUM_LABEL_FASTFORWARD_FRAMESKIP,
+   "fastforward_frameskip"
+   )
 MSG_HASH(
    MENU_ENUM_LABEL_FILE_BROWSER_CORE,
    "file_browser_core"

intl/msg_hash_us.h

@@ -3460,6 +3460,14 @@ MSG_HASH(
    MENU_ENUM_SUBLABEL_FASTFORWARD_RATIO,
    "The maximum rate at which content will be run when using fast-forward (e.g., 5.0x for 60 fps content = 300 fps cap). If set to 0.0x, fast-forward ratio is unlimited (no FPS cap)."
    )
+MSG_HASH(
+   MENU_ENUM_LABEL_VALUE_FASTFORWARD_FRAMESKIP,
+   "Fast-Forward Frameskip"
+   )
+MSG_HASH(
+   MENU_ENUM_SUBLABEL_FASTFORWARD_FRAMESKIP,
+   "Skip frames according to fast-forward rate. This conserves power and allows the use of 3rd party frame limiting."
+   )
 MSG_HASH(
    MENU_ENUM_LABEL_VALUE_SLOWMOTION_RATIO,
    "Slow-Motion Rate"

menu/cbs/menu_cbs_sublabel.c

@@ -494,6 +494,7 @@ DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_video_gpu_record,              MENU_
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_savestate_auto_index,          MENU_ENUM_SUBLABEL_SAVESTATE_AUTO_INDEX)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_block_sram_overwrite,          MENU_ENUM_SUBLABEL_BLOCK_SRAM_OVERWRITE)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_fastforward_ratio,             MENU_ENUM_SUBLABEL_FASTFORWARD_RATIO)
+DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_fastforward_frameskip,         MENU_ENUM_SUBLABEL_FASTFORWARD_FRAMESKIP)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_vrr_runloop_enable,            MENU_ENUM_SUBLABEL_VRR_RUNLOOP_ENABLE)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_slowmotion_ratio,              MENU_ENUM_SUBLABEL_SLOWMOTION_RATIO)
 DEFAULT_SUBLABEL_MACRO(action_bind_sublabel_run_ahead_enabled,             MENU_ENUM_SUBLABEL_RUN_AHEAD_ENABLED)
@@ -3409,6 +3410,9 @@ int menu_cbs_init_bind_sublabel(menu_file_list_cbs_t *cbs,
          case MENU_ENUM_LABEL_FASTFORWARD_RATIO:
             BIND_ACTION_SUBLABEL(cbs, action_bind_sublabel_fastforward_ratio);
             break;
+         case MENU_ENUM_LABEL_FASTFORWARD_FRAMESKIP:
+            BIND_ACTION_SUBLABEL(cbs, action_bind_sublabel_fastforward_frameskip);
+            break;
          case MENU_ENUM_LABEL_VRR_RUNLOOP_ENABLE:
             BIND_ACTION_SUBLABEL(cbs, action_bind_sublabel_vrr_runloop_enable);
             break;

menu/menu_displaylist.c

@@ -9393,6 +9393,7 @@ unsigned menu_displaylist_build_list(
 #endif
                {MENU_ENUM_LABEL_FRAME_TIME_COUNTER_SETTINGS, PARSE_ACTION},
                {MENU_ENUM_LABEL_FASTFORWARD_RATIO,       PARSE_ONLY_FLOAT},
+               {MENU_ENUM_LABEL_FASTFORWARD_FRAMESKIP,   PARSE_ONLY_BOOL },
                {MENU_ENUM_LABEL_SLOWMOTION_RATIO,        PARSE_ONLY_FLOAT},
                {MENU_ENUM_LABEL_VRR_RUNLOOP_ENABLE,      PARSE_ONLY_BOOL },
                {MENU_ENUM_LABEL_MENU_THROTTLE_FRAMERATE, PARSE_ONLY_BOOL },

menu/menu_setting.c

@@ -13950,6 +13950,22 @@ static bool setting_append_list(
          MENU_SETTINGS_LIST_CURRENT_ADD_CMD(list, list_info, CMD_EVENT_SET_FRAME_LIMIT);
          menu_settings_list_current_add_range(list, list_info, 0, 10, 1.0, true, true);
 
+         CONFIG_BOOL(
+               list, list_info,
+               &settings->bools.fastforward_frameskip,
+               MENU_ENUM_LABEL_FASTFORWARD_FRAMESKIP,
+               MENU_ENUM_LABEL_VALUE_FASTFORWARD_FRAMESKIP,
+               DEFAULT_FASTFORWARD_FRAMESKIP,
+               MENU_ENUM_LABEL_VALUE_OFF,
+               MENU_ENUM_LABEL_VALUE_ON,
+               &group_info,
+               &subgroup_info,
+               parent_group,
+               general_write_handler,
+               general_read_handler,
+               SD_FLAG_NONE
+               );
+
          CONFIG_BOOL(
                list, list_info,
                &settings->bools.vrr_runloop_enable,

msg_hash.h

@@ -1993,6 +1993,7 @@ enum msg_hash_enums
    MENU_LABEL(OVERLAY_CENTER_Y),
 
    MENU_LABEL(FASTFORWARD_RATIO),
+   MENU_LABEL(FASTFORWARD_FRAMESKIP),
    MENU_LABEL(VRR_RUNLOOP_ENABLE),
    MENU_LABEL(REWIND_ENABLE),
    MENU_LABEL(CHEAT_APPLY_AFTER_TOGGLE),

runloop.c

@@ -4910,6 +4910,22 @@ static bool core_unload_game(void)
    return true;
 }
 
+static void runloop_apply_fastmotion_frameskip(runloop_state_t *runloop_st, settings_t *settings)
+{
+   unsigned frames = 0;
+
+   if (runloop_st->fastmotion && settings->bools.fastforward_frameskip)
+   {
+      frames = (unsigned)settings->floats.fastforward_ratio;
+      /* Pick refresh rate as unlimited throttle rate */
+      frames = (!frames) ? (unsigned)roundf(settings->floats.video_refresh_rate) : frames;
+      /* Decrease one to represent skipped frames */
+      frames--;
+   }
+
+   runloop_st->fastforward_frameskip_frames_current = runloop_st->fastforward_frameskip_frames = frames;
+}
+
 static void runloop_apply_fastmotion_override(runloop_state_t *runloop_st, settings_t *settings)
 {
    video_driver_state_t *video_st                     = video_state_get_ptr();
@@ -4947,6 +4963,7 @@ static void runloop_apply_fastmotion_override(runloop_state_t *runloop_st, setti
       if (!runloop_st->fastmotion)
          runloop_st->fastforward_after_frames = 1;
 
+      runloop_apply_fastmotion_frameskip(runloop_st, settings);
       driver_set_nonblock_state();
 
       /* Reset frame time counter when toggling
@@ -7063,6 +7080,7 @@ static enum runloop_state_enum runloop_check_state(
             runloop_st->fastmotion            = true;
          }
 
+         runloop_apply_fastmotion_frameskip(runloop_st, settings);
          driver_set_nonblock_state();
 
          /* Reset frame time counter when toggling

runloop.h

@@ -216,6 +216,8 @@ struct runloop
    unsigned max_frames;
    unsigned audio_latency;
    unsigned fastforward_after_frames;
+   unsigned fastforward_frameskip_frames;
+   unsigned fastforward_frameskip_frames_current;
    unsigned perf_ptr_libretro;
    unsigned subsystem_current_count;
    unsigned entry_state_slot;