master 5df33cfcaf: Improve handling of XI2 wheel movement

[Po Lu]

branch: master
commit 5df33cfcaf379455857f2aefa5ca0ab39cb9fc6f
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Improve handling of XI2 wheel movement
    
    * src/xterm.c (handle_one_xevent): Process movement in all
    directions and send it as a single event.
---
 src/xterm.c | 107 ++++++++++++++++++++++++++++--------------------------------
 1 file changed, 50 insertions(+), 57 deletions(-)

diff --git a/src/xterm.c b/src/xterm.c
index 57e06f6c7e..b0d3adca0e 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -10968,13 +10968,12 @@ handle_one_xevent (struct x_display_info *dpyinfo,
          case XI_Motion:
            {
              struct xi_device_t *device;
-             bool touch_end_event_seen = false;
 
              states = &xev->valuators;
              values = states->values;
              device = xi_device_from_id (dpyinfo, xev->deviceid);
 
-             if (!device || !device->master_p)
+             if (!device)
                goto XI_OTHER;
 
 #ifdef XI_TouchBegin
@@ -10988,6 +10987,8 @@ handle_one_xevent (struct x_display_info *dpyinfo,
              double xv_total_x = 0.0;
              double xv_total_y = 0.0;
 #endif
+             double total_x = 0.0;
+             double total_y = 0.0;
 
              for (int i = 0; i < states->mask_len * 8; i++)
                {
@@ -11029,7 +11030,8 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                            }
 #endif
 
-                         found_valuator = true;
+                         if (delta == 0.0)
+                           found_valuator = true;
 
                          if (signbit (delta) != signbit (val->emacs_value))
                            val->emacs_value = 0;
@@ -11041,26 +11043,6 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                              && (fabs (delta) > 0))
                            continue;
 
-                         bool s = signbit (val->emacs_value);
-                         inev.ie.kind = (fabs (delta) > 0
-                                         ? (val->horizontal
-                                            ? HORIZ_WHEEL_EVENT
-                                            : WHEEL_EVENT)
-                                         : TOUCH_END_EVENT);
-                         inev.ie.timestamp = xev->time;
-
-                         XSETINT (inev.ie.x, lrint (xev->event_x));
-                         XSETINT (inev.ie.y, lrint (xev->event_y));
-                         XSETFRAME (inev.ie.frame_or_window, f);
-
-                         if (fabs (delta) > 0)
-                           {
-                             inev.ie.modifiers = !s ? up_modifier : 
down_modifier;
-                             inev.ie.modifiers
-                               |= x_x_to_emacs_modifiers (dpyinfo,
-                                                          xev->mods.effective);
-                           }
-
                          window = window_from_coordinates (f, xev->event_x,
                                                            xev->event_y, NULL,
                                                            false, false);
@@ -11078,40 +11060,15 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                          if (NUMBERP (Vx_scroll_event_delta_factor))
                            scroll_unit *= XFLOATINT 
(Vx_scroll_event_delta_factor);
 
-                         if (fabs (delta) > 0)
-                           {
-                             if (val->horizontal)
-                               {
-                                 inev.ie.arg
-                                   = list3 (Qnil,
-                                            make_float (val->emacs_value
-                                                        * scroll_unit),
-                                            make_float (0));
-                               }
-                             else
-                               {
-                                 inev.ie.arg = list3 (Qnil, make_float (0),
-                                                      make_float 
(val->emacs_value
-                                                                  * 
scroll_unit));
-                               }
-                           }
+                         if (val->horizontal)
+                           total_x += delta * scroll_unit;
                          else
-                           {
-                             inev.ie.arg = Qnil;
-                           }
-
-                         if (inev.ie.kind != TOUCH_END_EVENT
-                             || !touch_end_event_seen)
-                           {
-                             kbd_buffer_store_event_hold (&inev.ie, hold_quit);
-                             touch_end_event_seen = inev.ie.kind == 
TOUCH_END_EVENT;
-                           }
+                           total_y += delta * scroll_unit;
 
+                         found_valuator = true;
                          val->emacs_value = 0;
                        }
                    }
-
-                 inev.ie.kind = NO_EVENT;
                }
 
 #ifdef HAVE_XWIDGETS
@@ -11141,15 +11098,51 @@ handle_one_xevent (struct x_display_info *dpyinfo,
 
                  goto XI_OTHER;
                }
-#endif
-             if (found_valuator)
+             else
                {
+#endif
+                 if (found_valuator)
+                   {
+                     if (fabs (total_x) > 0 || fabs (total_y) > 0)
+                       {
+                         inev.ie.kind = (fabs (total_y) >= fabs (total_x)
+                                         ? WHEEL_EVENT : HORIZ_WHEEL_EVENT);
+                         inev.ie.timestamp = xev->time;
+
+                         XSETINT (inev.ie.x, lrint (xev->event_x));
+                         XSETINT (inev.ie.y, lrint (xev->event_y));
+                         XSETFRAME (inev.ie.frame_or_window, f);
+
+                         inev.ie.modifiers = (signbit (fabs (total_y) >= fabs 
(total_x)
+                                                       ? total_y : total_x)
+                                              ? down_modifier : up_modifier);
+                         inev.ie.modifiers
+                           |= x_x_to_emacs_modifiers (dpyinfo,
+                                                      xev->mods.effective);
+                         inev.ie.arg = list3 (Qnil,
+                                              make_float (total_x),
+                                              make_float (total_y));
+
 #ifdef USE_GTK
-                 if (f && xg_event_is_for_scrollbar (f, event))
-                   *finish = X_EVENT_DROP;
+                         if (f && xg_event_is_for_scrollbar (f, event))
+                           *finish = X_EVENT_DROP;
 #endif
-                 goto XI_OTHER;
+                       }
+                     else
+                       {
+                         inev.ie.kind = TOUCH_END_EVENT;
+                         inev.ie.timestamp = xev->time;
+
+                         XSETINT (inev.ie.x, lrint (xev->event_x));
+                         XSETINT (inev.ie.y, lrint (xev->event_y));
+                         XSETFRAME (inev.ie.frame_or_window, f);
+                       }
+
+                     goto XI_OTHER;
+                   }
+#ifdef HAVE_XWIDGETS
                }
+#endif
 
              ev.x = lrint (xev->event_x);
              ev.y = lrint (xev->event_y);