elm scroller - add adnimated and accelerated wheel scroll

now when a whele event comes in, 1. the amount we scroll accelerates
based on time between wheel events (the faster wheel events come out,
the more accel), and 2. we animate to the new position providing a
smooth transition to the new spot rather than a jump. very visually
nice.

@feature

diff --git a/src/lib/elm_interface_scrollable.c b/src/lib/elm_interface_scrollable.c
index d1b818aeba031ffc29fa93fa86980e9c41466f0a..e510ac1be6bf3325c703f182d9ba33f4fe8d75de 100644 (file)
--- a/src/lib/elm_interface_scrollable.c
+++ b/src/lib/elm_interface_scrollable.c
@@ -1817,6 +1817,7 @@ _elm_scroll_wheel_event_cb(void *data,
    Evas_Coord x = 0, y = 0, vw = 0, vh = 0, cw = 0, ch = 0;
    int direction = 0;
    int pagenumber_h = 0, pagenumber_v = 0;
+   int mx = 0, my = 0, minx = 0, miny = 0;
 
    sid = data;
    ev = event_info;
@@ -1835,6 +1836,15 @@ _elm_scroll_wheel_event_cb(void *data,
    else if (evas_key_modifier_is_set(ev->modifiers, "Shift"))
      direction = !direction;
    eo_do(sid->obj, elm_interface_scrollable_content_pos_get(&x, &y));
+   if (sid->scrollto.x.animator) x = sid->scrollto.x.end;
+   if (sid->scrollto.y.animator) y = sid->scrollto.y.end;
+   eo_do(sid->pan_obj, elm_obj_pan_pos_max_get(&mx, &my));
+   eo_do(sid->pan_obj, elm_obj_pan_pos_min_get(&minx, &miny));
+   if (x < minx) x = minx;
+   if (x > mx) x = mx;
+   if (y < miny) y = miny;
+   if (y > my) y = my;
+
    if ((sid->down.bounce_x_animator) || (sid->down.bounce_y_animator) ||
        (sid->scrollto.x.animator) || (sid->scrollto.y.animator))
      {
@@ -1862,25 +1872,29 @@ _elm_scroll_wheel_event_cb(void *data,
      eo_do(sid->pan_obj, elm_obj_pan_content_size_get(&cw, &ch));
    if (!_paging_is_enabled(sid))
      {
+        int d = ev->z;
+        double delta_t = (double)(ev->timestamp - sid->last_wheel) / 1000.0;
+        double mul;
+
+        mul = 1.0 + (7.0 * ((0.2 - delta_t) / 0.2));
+        if (delta_t < 0.2) d *= mul;
+        sid->last_wheel = ev->timestamp;
         if (!direction)
           {
-             if (ch > vh || cw <= vw)
-               y += ev->z * sid->step.y;
-             else
-               x += ev->z * sid->step.x;
+             if ((ch > vh) || (cw <= vw)) y += d * sid->step.y;
+             else x += d * sid->step.x;
           }
         else if (direction == 1)
           {
-             if (cw > vw || ch <= vh)
-               x += ev->z * sid->step.x;
-             else
-               y += ev->z * sid->step.y;
+             if ((cw > vw) || (ch <= vh)) x += d * sid->step.x;
+             else y += d * sid->step.y;
           }
 
         if ((!sid->hold) && (!sid->freeze))
           {
              _elm_scroll_wanted_coordinates_update(sid, x, y);
-             eo_do(sid->obj, elm_interface_scrollable_content_pos_set(x, y, EINA_TRUE));
+             _elm_scroll_scroll_to_x(sid, _elm_config->bring_in_scroll_friction, x);
+             _elm_scroll_scroll_to_y(sid, _elm_config->bring_in_scroll_friction, y);
           }
      }
    else
@@ -1903,6 +1917,7 @@ _elm_scroll_wheel_event_cb(void *data,
 
         if ((!sid->hold) && (!sid->freeze))
           {
+             _elm_scroll_wanted_coordinates_update(sid, x, y);
              _elm_scroll_scroll_to_x(sid, _elm_config->bring_in_scroll_friction, x);
              _elm_scroll_scroll_to_y(sid, _elm_config->bring_in_scroll_friction, y);
           }

diff --git a/src/lib/elm_interface_scrollable.h b/src/lib/elm_interface_scrollable.h
index 25f50a14bf40260633aeb644c21c96fea1982811..5ae8947e2629b0aef5db0c31f0cd80dd7a7cf2ec 100644 (file)
--- a/src/lib/elm_interface_scrollable.h
+++ b/src/lib/elm_interface_scrollable.h
@@ -185,6 +185,8 @@ struct _Elm_Scrollable_Smart_Interface_Data
    int        page_limit_h, page_limit_v;
    int        current_calc;
 
+   unsigned int last_wheel;
+
    unsigned char size_adjust_recurse;
    unsigned char size_count;
    Eina_Bool  size_adjust_recurse_abort : 1;