[gtk+/wip/mir2] mir: use old scrolling system if we get simple integer values

[Marco Trevisan <marcotrevi src gnome org>]

commit 84119c20f297e4d02f4667a3d4d921e785fd77e9
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Fri Dec 12 01:40:55 2014 +0100

    mir: use old scrolling system if we get simple integer values

 gdk/mir/gdkmireventsource.c |   18 +++++++++++++++---
 1 files changed, 15 insertions(+), 3 deletions(-)
---
diff --git a/gdk/mir/gdkmireventsource.c b/gdk/mir/gdkmireventsource.c
index caa07b1..8a16528 100644
--- a/gdk/mir/gdkmireventsource.c
+++ b/gdk/mir/gdkmireventsource.c
@@ -167,11 +167,23 @@ generate_scroll_event (GdkWindow *window, gdouble x, gdouble y, gdouble delta_x,
   event->scroll.x = x;
   event->scroll.y = y;
   event->scroll.state = state;
-  event->scroll.direction = GDK_SCROLL_SMOOTH;
-  event->scroll.delta_x = -delta_x;
-  event->scroll.delta_y = -delta_y;
   event->scroll.time = event_time;
 
+  if (ABS (delta_x) == 1 && delta_y == 0)
+    {
+      event->scroll.direction = (delta_x < 0) ? GDK_SCROLL_LEFT : GDK_SCROLL_RIGHT;
+    }
+  else if (ABS (delta_y) == 1 && delta_x == 0)
+    {
+      event->scroll.direction = (delta_y < 0) ? GDK_SCROLL_DOWN : GDK_SCROLL_UP;
+    }
+  else
+    {
+      event->scroll.direction = GDK_SCROLL_SMOOTH;
+      event->scroll.delta_x = -delta_x;
+      event->scroll.delta_y = -delta_y;
+    }
+
   send_event (window, get_pointer (window), event);
 }