Merge lp:~cimi/overlay-scrollbar/animated-thumb-fade-out into lp:overlay-scrollbar

[Andrea Cimitan]

as in the bugreport, add a fade-out animation

[Kalle Valo (kvalo)]

Good looking code and didn't find anything wrong.

review: Approve

[lp:~cimi/overlay-scrollbar/animated-thumb-fade-out]

194. By Andrea Cimitan on 2011-04-05

Added few comments, try to avoid useless calls ("faster code is code that doesn't execute").

[Kalle Valo (kvalo)]

Update looks good as well.

review: Approve

[lp:~cimi/overlay-scrollbar/animated-thumb-fade-out]

195. By Andrea Cimitan on 2011-04-05

stop the animation on leave-notify only if there's an active timeout

[Loïc Molinari (loic.molinari)]

Why not using the end animation callback of OsAnimation instead of testing if weight is equal to 1.0 in os_thumb_fade_out_cb()?

The comment in os_thumb_button_release_event() says that "priv->source_id should be always != 0". I guess you meant "== 0" here, otherwise I think you should remove the source from the mainloop first. In any case, adding a debug assert "OS_DCHECK (priv->source_id == 0);" would be very useful there to make sure it's really the case.

Apart from that, looks good to me too.

[Andrea Cimitan (cimi)]

Because the end animation fallback iirc is called also when you stop the animation (that's why I've chosen to do in that way... but maybe was late the previous night, let me check :-) )

[lp:~cimi/overlay-scrollbar/animated-thumb-fade-out]

196. By Andrea Cimitan on 2011-04-05

fixed comment

[Andrea Cimitan (cimi)]

exactly: os_animation_stop () calls the end_func, so if I put a gtk_widget_hide there, this will be called everytime I stop the fade-out (so if the widget is 90% opaque, it will be hidden), and I don't want it to stop everytime, but only if weight == 1.0f.
Yeah, I could write a complex end_func just to check the opacity of the window, but it's more expensive, isn't it?

[Loïc Molinari (loic.molinari)]

I get it. Actually I see no good reason for stop to call the end callback. Maybe we should remove it. What do you think?

=== modified file 'os/os-thumb.c'
--- os/os-thumb.c	2011-04-04 16:25:26 +0000
+++ os/os-thumb.c	2011-04-05 16:01:57 +0000
@@ -25,15 +25,28 @@
 #endif /* HAVE_CONFIG_H */
 
 #include "os-private.h"
+#include "math.h"
+
+/* Rate of the fade-out */
+#define RATE_FADE_OUT 30
+
+/* Duration of the fade-out */
+#define DURATION_FADE_OUT 2000
+
+/* Timeout before the fade-out */
+#define TIMEOUT_FADE_OUT 250
 
 struct _OsThumbPrivate {
   GtkOrientation orientation;
   GtkWidget *grabbed_widget;
+  OsAnimation *animation;
   gboolean button_press_event;
+  gboolean enter_notify_event;
   gboolean motion_notify_event;
   gboolean can_rgba;
   gint pointer_x;
   gint pointer_y;
+  guint32 source_id;
 };
 
 enum {
@@ -42,10 +55,14 @@
   LAST_ARG
 };
 
+static void os_thumb_fade_out_cb (gfloat weight, gpointer user_data);
+static gboolean os_thumb_timeout_fade_out_cb (gpointer user_data);
 static gboolean os_thumb_button_press_event (GtkWidget *widget, GdkEventButton *event);
 static gboolean os_thumb_button_release_event (GtkWidget *widget, GdkEventButton *event);
 static void os_thumb_composited_changed (GtkWidget *widget);
+static gboolean os_thumb_enter_notify_event (GtkWidget *widget, GdkEventCrossing *event);
 static gboolean os_thumb_expose (GtkWidget *widget, GdkEventExpose *event);
+static gboolean os_thumb_leave_notify_event (GtkWidget *widget, GdkEventCrossing *event);
 static gboolean os_thumb_motion_notify_event (GtkWidget *widget, GdkEventMotion *event);
 static void os_thumb_map (GtkWidget *widget);
 static void os_thumb_screen_changed (GtkWidget *widget, GdkScreen *old_screen);
@@ -83,6 +100,43 @@
   cairo_arc (cr, x + radius, y + radius, radius, G_PI, G_PI * 1.5);
 }
 
+static void
+os_thumb_fade_out_cb (gfloat weight,
+                      gpointer user_data)
+{
+  OsThumb *thumb;
+  OsThumbPrivate *priv;
+
+  thumb = OS_THUMB (user_data);
+
+  priv = thumb->priv;
+
+  if (weight < 1.0f)
+    gtk_window_set_opacity (GTK_WINDOW (thumb), fabs (weight - 1.0f));
+  else
+    {
+      /* Animation ended. */
+      priv->source_id = 0;
+
+      gtk_widget_hide (GTK_WIDGET (thumb));
+    }
+}
+
+static gboolean
+os_thumb_timeout_fade_out_cb (gpointer user_data)
+{
+  OsThumb *thumb;
+  OsThumbPrivate *priv;
+
+  thumb = OS_THUMB (user_data);
+
+  priv = thumb->priv;
+
+  os_animation_start (priv->animation);
+
+  return FALSE;
+}
+
 /* Type definition. */
 
 G_DEFINE_TYPE (OsThumb, os_thumb, GTK_TYPE_WINDOW);
@@ -99,7 +153,9 @@
   widget_class->button_press_event   = os_thumb_button_press_event;
   widget_class->button_release_event = os_thumb_button_release_event;
   widget_class->composited_changed   = os_thumb_composited_changed;
+  widget_class->enter_notify_event   = os_thumb_enter_notify_event;
   widget_class->expose_event         = os_thumb_expose;
+  widget_class->leave_notify_event   = os_thumb_leave_notify_event;
   widget_class->map                  = os_thumb_map;
   widget_class->motion_notify_event  = os_thumb_motion_notify_event;
   widget_class->screen_changed       = os_thumb_screen_changed;
@@ -134,6 +190,10 @@
 
   priv->can_rgba = FALSE;
 
+  priv->source_id = 0;
+  priv->animation = os_animation_new (RATE_FADE_OUT, DURATION_FADE_OUT,
+                                      os_thumb_fade_out_cb, NULL, thumb);
+
   gtk_window_set_skip_pager_hint (GTK_WINDOW (thumb), TRUE);
   gtk_window_set_skip_taskbar_hint (GTK_WINDOW (thumb), TRUE);
   /* gtk_window_set_has_resize_grip (GTK_WINDOW (thumb), FALSE); */
@@ -143,7 +203,7 @@
   gtk_widget_set_app_paintable (GTK_WIDGET (thumb), TRUE);
   gtk_widget_add_events (GTK_WIDGET (thumb), GDK_BUTTON_PRESS_MASK |
                                              GDK_BUTTON_RELEASE_MASK |
-                                             GDK_BUTTON_MOTION_MASK |
+                                             GDK_POINTER_MOTION_MASK |
                                              GDK_POINTER_MOTION_HINT_MASK);
 
   os_thumb_screen_changed (GTK_WIDGET (thumb), NULL);
@@ -153,6 +213,24 @@
 static void
 os_thumb_dispose (GObject *object)
 {
+  OsThumb *thumb;
+  OsThumbPrivate *priv;
+
+  thumb = OS_THUMB (object);
+  priv = thumb->priv;
+
+  if (priv->source_id != 0)
+    {
+      g_source_remove (priv->source_id);
+      priv->source_id = 0;
+    }
+
+  if (priv->animation != NULL)
+    {
+      g_object_unref (priv->animation);
+      priv->animation = NULL;
+    }
+
   G_OBJECT_CLASS (os_thumb_parent_class)->dispose (object);
 }
 
@@ -167,16 +245,27 @@
 os_thumb_button_press_event (GtkWidget      *widget,
                              GdkEventButton *event)
 {
+  OsThumb *thumb;
+  OsThumbPrivate *priv;
+
+  thumb = OS_THUMB (widget);
+  priv = thumb->priv;
+
+  /* Stop the animation on user interaction,
+   * the button_press_event. */
+  if (priv->source_id != 0)
+    {
+      g_source_remove (priv->source_id);
+      priv->source_id = 0;
+
+      os_animation_stop (priv->animation);
+      gtk_window_set_opacity (GTK_WINDOW (widget), 1.0f);
+    }
+
   if (event->type == GDK_BUTTON_PRESS)
     {
       if (event->button == 1)
         {
-          OsThumb *thumb;
-          OsThumbPrivate *priv;
-
-          thumb = OS_THUMB (widget);
-          priv = thumb->priv;
-
           gtk_grab_add (widget);
 
           priv->pointer_x = event->x;
@@ -196,16 +285,26 @@
 os_thumb_button_release_event (GtkWidget      *widget,
                                GdkEventButton *event)
 {
+  OsThumb *thumb;
+  OsThumbPrivate *priv;
+
+  thumb = OS_THUMB (widget);
+  priv = thumb->priv;
+
+  /* priv->source_id should be always 0 here,
+   * because it's set to 0 in both motion_notify_event
+   * and button_press_event.
+   * Add the fade-out timeout only if the pointer is inside,
+   * so if priv->enter_notify_event is TRUE. */
+  if (priv->enter_notify_event)
+    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)
         {
-          OsThumb *thumb;
-          OsThumbPrivate *priv;
-
-          thumb = OS_THUMB (widget);
-          priv = thumb->priv;
-
           gtk_grab_remove (widget);
 
           priv->button_press_event = FALSE;
@@ -245,6 +344,21 @@
 }
 
 static gboolean
+os_thumb_enter_notify_event (GtkWidget        *widget,
+                             GdkEventCrossing *event)
+{
+  OsThumb *thumb;
+  OsThumbPrivate *priv;
+
+  thumb = OS_THUMB (widget);
+  priv = thumb->priv;
+
+  priv->enter_notify_event = TRUE;
+
+  return FALSE;
+}
+
+static gboolean
 os_thumb_expose (GtkWidget      *widget,
                  GdkEventExpose *event)
 {
@@ -451,6 +565,36 @@
   return FALSE;
 }
 
+static gboolean
+os_thumb_leave_notify_event (GtkWidget        *widget,
+                             GdkEventCrossing *event)
+{
+  OsThumb *thumb;
+  OsThumbPrivate *priv;
+
+  thumb = OS_THUMB (widget);
+  priv = thumb->priv;
+
+  priv->enter_notify_event = FALSE;
+
+  /* If we exit the thumb when a button is pressed,
+   * there's no need to stop the animation, it should
+   * already be stopped.
+   * Stop it only if priv->button_press_event is FALSE. */
+  if (!priv->button_press_event)
+    {
+      if (priv->source_id != 0)
+        {
+          g_source_remove (priv->source_id);
+          priv->source_id = 0;
+
+          os_animation_stop (priv->animation);
+        }
+    }
+
+  return FALSE;
+}
+
 static void
 os_thumb_map (GtkWidget *widget)
 {
@@ -478,6 +622,24 @@
   thumb = OS_THUMB (widget);
   priv = thumb->priv;
 
+  /* On motion, stop the fade-out. */
+  if (priv->source_id != 0)
+    {
+      g_source_remove (priv->source_id);
+      priv->source_id = 0;
+
+      os_animation_stop (priv->animation);
+      gtk_window_set_opacity (GTK_WINDOW (widget), 1.0f);
+    }
+
+  /* If you're not dragging, 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->button_press_event)
     {
       if (!priv->motion_notify_event)
@@ -513,6 +675,7 @@
   priv = thumb->priv;
 
   priv->button_press_event = FALSE;
+  priv->enter_notify_event = FALSE;
   priv->motion_notify_event = FALSE;
 
   if (priv->grabbed_widget != NULL)