implement smooth seeking acceleration for audio playback and mpegplayer

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17843 a1c6a512-1295-4272-9138-f99709370657

4 files changed, 78 insertions, 20 deletions

diff --git a/apps/gui/gwps-common.c b/apps/gui/gwps-common.c
index b53d68d6ba..3fd77a2211 100644
--- a/apps/gui/gwps-common.c
+++ b/apps/gui/gwps-common.c
@@ -196,10 +196,10 @@ bool ffwd_rew(int button)
     unsigned int max_step = 0; /* maximum ff/rewind step */ 
     int ff_rewind_count = 0;   /* current ff/rewind count (in ticks) */
     int direction = -1;         /* forward=1 or backward=-1 */
-    long accel_tick = 0;       /* next time at which to bump the step size */
     bool exit = false;
     bool usb = false;
     int i = 0;
+    const long ff_rw_accel = (global_settings.ff_rewind_accel + 3);
 
     if (button == ACTION_NONE)
     {
@@ -237,13 +237,8 @@ bool ffwd_rew(int button)
 
                     ff_rewind_count += step * direction;
 
-                    if (global_settings.ff_rewind_accel != 0 && 
-                        current_tick >= accel_tick)
-                    { 
-                        step *= 2;
-                        accel_tick = current_tick +
-                            global_settings.ff_rewind_accel*HZ; 
-                    } 
+                    /* smooth seeking by multiplying step by: 1 + (2 ^ -accel) */
+                    step += step >> ff_rw_accel;
                 }
                 else
                 {
@@ -268,9 +263,6 @@ bool ffwd_rew(int button)
                         wps_state.ff_rewind = true;
 
                         step = 1000 * global_settings.ff_rewind_min_step;
-
-                        accel_tick = current_tick +
-                            global_settings.ff_rewind_accel*HZ; 
                     }
                     else
                         break;
diff --git a/apps/lang/english.lang b/apps/lang/english.lang
index 757fa58bb6..02ecdd5ad9 100644
--- a/apps/lang/english.lang
+++ b/apps/lang/english.lang
@@ -11750,3 +11750,71 @@
     gigabeatf: "High"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_VERY_SLOW
+  desc: in settings_menu
+  user:
+  <source>
+    *: none
+    gigabeatf: "Very slow"
+  </source>
+  <dest>
+    *: none
+    gigabeatf: "Very slow"
+  </dest>
+  <voice>
+    *: none
+    gigabeatf: "Very slow"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_SLOW
+  desc: in settings_menu
+  user:
+  <source>
+    *: none
+    gigabeatf: "Slow"
+  </source>
+  <dest>
+    *: none
+    gigabeatf: "Slow"
+  </dest>
+  <voice>
+    *: none
+    gigabeatf: "Slow"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_VERY_FAST
+  desc: in settings_menu
+  user:
+  <source>
+    *: none
+    gigabeatf: "Very fast"
+  </source>
+  <dest>
+    *: none
+    gigabeatf: "Very fast"
+  </dest>
+  <voice>
+    *: none
+    gigabeatf: "Very fast"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_FAST
+  desc: in settings_menu
+  user:
+  <source>
+    *: none
+    gigabeatf: "Fast"
+  </source>
+  <dest>
+    *: none
+    gigabeatf: "Fast"
+  </dest>
+  <voice>
+    *: none
+    gigabeatf: "Fast"
+  </voice>
+</phrase>
diff --git a/apps/plugins/mpegplayer/mpegplayer.c b/apps/plugins/mpegplayer/mpegplayer.c
index 6d6aa2078f..5b478d0bf7 100644
--- a/apps/plugins/mpegplayer/mpegplayer.c
+++ b/apps/plugins/mpegplayer/mpegplayer.c
@@ -1109,8 +1109,7 @@ static int wvs_get_status(void)
 static uint32_t wvs_ff_rw(int btn, unsigned refresh)
 {
     unsigned int step = TS_SECOND*rb->global_settings->ff_rewind_min_step;
-    const long ff_rw_accel = rb->global_settings->ff_rewind_accel;
-    long accel_tick = *rb->current_tick + ff_rw_accel*HZ;
+    const long ff_rw_accel = (rb->global_settings->ff_rewind_accel + 3);
     uint32_t start;
     uint32_t time = stream_get_seek_time(&start);
     const uint32_t duration = stream_get_duration();
@@ -1145,7 +1144,6 @@ static uint32_t wvs_ff_rw(int btn, unsigned refresh)
 
     while (1)
     {
-        long tick = *rb->current_tick;
         stream_keep_disk_active();
 
         switch (btn)
@@ -1199,10 +1197,8 @@ static uint32_t wvs_ff_rw(int btn, unsigned refresh)
 
         ff_rw_count += step;
 
-        if (ff_rw_accel != 0 && TIME_AFTER(tick, accel_tick)) { 
-            step *= 2;
-            accel_tick = tick + ff_rw_accel*HZ; 
-        }
+        /* smooth seeking by multiplying step by: 1 + (2 ^ -accel) */
+        step += step >> ff_rw_accel;
 
         if (wvs.status == WVS_STATUS_FF) {
             if (duration - time <= ff_rw_count)
diff --git a/apps/settings_list.c b/apps/settings_list.c
index 6007570bf8..1e9bd185b7 100644
--- a/apps/settings_list.c
+++ b/apps/settings_list.c
@@ -666,8 +666,10 @@ const struct settings_list settings[] = {
     TABLE_SETTING(F_ALLOW_ARBITRARY_VALS, ff_rewind_min_step,
                   LANG_FFRW_STEP, 1, "scan min step", NULL, UNIT_SEC,
                   NULL, NULL, NULL, 14,  1,2,3,4,5,6,8,10,15,20,25,30,45,60),
-    INT_SETTING(0, ff_rewind_accel, LANG_FFRW_ACCEL, 3, "scan accel", UNIT_SEC,
-                16, 0, -1, scanaccel_formatter, getlang_unit_0_is_off, NULL),
+    CHOICE_SETTING(0, ff_rewind_accel, LANG_FFRW_ACCEL, 2,
+                   "seek accel", "very fast,fast,normal,slow,very slow", NULL, 5,
+                   ID2P(LANG_VERY_FAST), ID2P(LANG_FAST), ID2P(LANG_NORMAL),
+                   ID2P(LANG_SLOW) , ID2P(LANG_VERY_SLOW)),
 #if (CONFIG_CODEC == SWCODEC) && !defined(HAVE_FLASH_STORAGE)
     STRINGCHOICE_SETTING(0, buffer_margin, LANG_MP3BUFFER_MARGIN, 0,"antiskip",
                          "5s,15s,30s,1min,2min,3min,5min,10min", NULL, 8,