elm scroller accel was broken by default confgis setting it to 0. fix

now set default wheel scroll accel to 7 as epr the confgi upgrade code
and also improve the acceleration to "rely on itself" and feedback
loop. this is so much better now i can scroll through things in a
whisk with the wheel.

fixes T4263

@fix

2 files changed, 6 insertions, 1 deletions

diff --git a/src/lib/elementary/elm_interface_scrollable.c b/src/lib/elementary/elm_interface_scrollable.c
index a92a503ed4..7c14d31e25 100644
--- a/src/lib/elementary/elm_interface_scrollable.c
+++ b/src/lib/elementary/elm_interface_scrollable.c
@@ -1942,9 +1942,13 @@ _scroll_wheel_post_event_cb(void *data, Evas *e EINA_UNUSED)
         double delta_t = (double)(ev->timestamp - sid->last_wheel) / 1000.0;
         double mul;
 
+        if (delta_t > 0.2) sid->last_wheel_mul = 0.0;
+        if (delta_t > 0.2) delta_t = 0.2;
         mul = 1.0 + (_elm_config->scroll_accel_factor * ((0.2 - delta_t) / 0.2));
-        if (delta_t < 0.2) d *= mul;
+        mul = mul * (1.0 + (0.15 * sid->last_wheel_mul));
+        d *= mul;
         sid->last_wheel = ev->timestamp;
+        sid->last_wheel_mul = mul;
         if (!direction)
           {
              if ((ch > vh) || (cw <= vw)) y += d * sid->step.y;
diff --git a/src/lib/elementary/elm_interface_scrollable.h b/src/lib/elementary/elm_interface_scrollable.h
index 21e17ffa97..f2167267ab 100644
--- a/src/lib/elementary/elm_interface_scrollable.h
+++ b/src/lib/elementary/elm_interface_scrollable.h
@@ -193,6 +193,7 @@ struct _Elm_Scrollable_Smart_Interface_Data
    int        page_limit_h, page_limit_v;
    int        current_calc;
 
+   double       last_wheel_mul;
    unsigned int last_wheel;
 
    unsigned char size_adjust_recurse;