From cfbec687e544d3b77e7f225dd63a679ddc2100c7 Mon Sep 17 00:00:00 2001
From: jdgleaver <james@leaver.myzen.co.uk>
Date: Mon, 4 Mar 2019 15:30:12 +0000
Subject: [PATCH] Make runtime independent of fast forward/slow motion
---
retroarch.c | 35 ++++++++++++++++++++++++++++++++++-
1 file changed, 34 insertions(+), 1 deletion(-)
diff --git a/retroarch.c b/retroarch.c
index 142a96c19f..e602528492 100644
--- a/retroarch.c
+++ b/retroarch.c
@@ -277,6 +277,7 @@ static unsigned fastforward_after_frames = 0;
static retro_usec_t runloop_frame_time_last = 0;
static retro_time_t frame_limit_minimum_time = 0.0;
static retro_time_t frame_limit_last_time = 0.0;
+static retro_time_t libretro_core_runtime_last = 0;
static retro_time_t libretro_core_runtime_usec = 0;
extern bool input_driver_flushing_input;
@@ -807,10 +808,41 @@ bool driver_ctl(enum driver_ctl_state state, void *data)
void rarch_core_runtime_tick(void)
{
+ retro_time_t frame_time;
struct retro_system_av_info *av_info = video_viewport_get_system_av_info();
if (av_info && av_info->timing.fps)
- libretro_core_runtime_usec += (1.0 / av_info->timing.fps) * 1000 * 1000;
+ {
+ frame_time = (1.0 / av_info->timing.fps) * 1000000;
+
+ /* Account for slow motion */
+ if (runloop_slowmotion)
+ {
+ settings_t *settings = config_get_ptr();
+ if (settings)
+ frame_time = (retro_time_t)((double)frame_time * settings->floats.slowmotion_ratio);
+ }
+ /* Account for fast forward */
+ else if (runloop_fastmotion)
+ {
+ /* Doing it this way means we miss the first frame after
+ * turning fast forward on, but it saves the overhead of
+ * having to do:
+ * retro_time_t current_usec = cpu_features_get_time_usec();
+ * libretro_core_runtime_last = current_usec;
+ * every frame when fast forward is off. */
+ retro_time_t current_usec = cpu_features_get_time_usec();
+
+ if (current_usec - libretro_core_runtime_last < frame_time)
+ {
+ frame_time = current_usec - libretro_core_runtime_last;
+ }
+
+ libretro_core_runtime_last = current_usec;
+ }
+
+ libretro_core_runtime_usec += frame_time;
+ }
}
#ifdef HAVE_THREADS
@@ -2382,6 +2414,7 @@ bool rarch_ctl(enum rarch_ctl_state state, void *data)
}
break;
case RARCH_CTL_CONTENT_RUNTIME_LOG_INIT:
+ libretro_core_runtime_last = cpu_features_get_time_usec();
libretro_core_runtime_usec = 0;
break;
case RARCH_CTL_CONTENT_RUNTIME_LOG_DEINIT: