Merge lp:~cimi/overlay-scrollbar/fix-758046 into lp:overlay-scrollbar

[Andrea Cimitan]

Implement tolerance

[Ted Gould (ted)]

You shouldn't need to use the floating point absolute value here. (fabs). Other than that it seems good.

review: Approve

[lp:~cimi/overlay-scrollbar/fix-758046]

208. By Andrea Cimitan on 2011-04-13

use abs instead fabs

=== modified file 'os/os-thumb.c'
--- os/os-thumb.c	2011-04-07 16:14:09 +0000
+++ os/os-thumb.c	2011-04-13 09:34:31 +0000
@@ -27,15 +27,18 @@
 #include "os-private.h"
 #include "math.h"
 
-/* Rate of the fade-out */
+/* Rate of the fade-out. */
 #define RATE_FADE_OUT 30
 
-/* Duration of the fade-out */
+/* Duration of the fade-out. */
 #define DURATION_FADE_OUT 2000
 
-/* Timeout before the fade-out */
+/* Timeout before the fade-out. */
 #define TIMEOUT_FADE_OUT 250
 
+/* Number of tolerance pixels. */
+#define TOLERANCE_PIXELS 3
+
 struct _OsThumbPrivate {
   GtkOrientation orientation;
   GtkWidget *grabbed_widget;
@@ -43,6 +46,7 @@
   gboolean button_press_event;
   gboolean motion_notify_event;
   gboolean can_rgba;
+  gboolean use_tolerance;
   gint pointer_x;
   gint pointer_y;
   guint32 source_id;
@@ -279,6 +283,8 @@
           priv->button_press_event = TRUE;
           priv->motion_notify_event = FALSE;
 
+          priv->use_tolerance = TRUE;
+
           gtk_widget_queue_draw (widget);
         }
     }
@@ -299,21 +305,6 @@
 
   gtk_widget_get_allocation (widget, &allocation);
 
-  if (priv->source_id != 0)
-    {
-      g_source_remove (priv->source_id);
-      priv->source_id = 0;
-    }
-
-  /* Add the fade-out timeout only
-   * if the pointer is inside the thumb.
-   * allocation.x and allocation.y are always 0. */
-  if ((event->x >= 0 && event->x <= allocation.width) &&
-      (event->y >= 0 && event->y <= allocation.height))
-    priv->source_id = g_timeout_add (TIMEOUT_FADE_OUT,
-                                     os_thumb_timeout_fade_out_cb,
-                                     thumb);
-
   if (event->type == GDK_BUTTON_RELEASE)
     {
       if (event->button == 1)
@@ -588,6 +579,8 @@
         }
     }
 
+  priv->use_tolerance = FALSE;
+
   return FALSE;
 }
 
@@ -637,13 +630,22 @@
       gtk_window_set_opacity (GTK_WINDOW (widget), 1.0f);
     }
 
-  /* If you're not dragging, enable the fade-out.
+  /* If you're not dragging, and you're outside
+   * the tolerance pixels, enable the fade-out.
    * priv->motion_notify_event is TRUE only on dragging,
    * see code few lines below. */
   if (!priv->motion_notify_event)
-    priv->source_id = g_timeout_add (TIMEOUT_FADE_OUT,
-                                     os_thumb_timeout_fade_out_cb,
-                                     thumb);
+  {
+    if (!priv->use_tolerance ||
+        (abs (priv->pointer_x - event->x) > TOLERANCE_PIXELS ||
+         abs (priv->pointer_y - event->y) > TOLERANCE_PIXELS))
+      {
+        priv->use_tolerance = FALSE;
+        priv->source_id = g_timeout_add (TIMEOUT_FADE_OUT,
+                                         os_thumb_timeout_fade_out_cb,
+                                         thumb);
+      }
+  }
 
   if (priv->button_press_event)
     {
@@ -709,6 +711,8 @@
   priv->button_press_event = FALSE;
   priv->motion_notify_event = FALSE;
 
+  priv->use_tolerance = FALSE;
+
   if (priv->grabbed_widget != NULL)
     gtk_grab_add (priv->grabbed_widget);