[epiphany/downloads: 11/12] totem-glow-button: a glow button derived from libwnck

[Diego Escalante Urrelo <diegoe src gnome org>]

commit e5ca63cc920f56d56c507fc6fb938fcfa878af84
Author: Diego Escalante Urrelo <descalante igalia com>
Date:   Thu Jan 20 14:58:42 2011 -0500

    totem-glow-button: a glow button derived from libwnck

 lib/widgets/Makefile.am         |    2 +
 lib/widgets/totem-glow-button.c |  351 +++++++++++++++++++++++++++++++++++++++
 lib/widgets/totem-glow-button.h |   52 ++++++
 3 files changed, 405 insertions(+), 0 deletions(-)
---
diff --git a/lib/widgets/Makefile.am b/lib/widgets/Makefile.am
index f1e2f0d..8e074a8 100644
--- a/lib/widgets/Makefile.am
+++ b/lib/widgets/Makefile.am
@@ -11,6 +11,8 @@ libephywidgets_la_SOURCES = \
 	ephy-tree-model-node.h			\
 	ephy-tree-model-sort.c			\
 	ephy-tree-model-sort.h			\
+	totem-glow-button.c			\
+	totem-glow-button.h			\
 	ephy-zoom-action.h			\
 	ephy-zoom-action.c			\
 	ephy-zoom-control.c			\
diff --git a/lib/widgets/totem-glow-button.c b/lib/widgets/totem-glow-button.c
new file mode 100644
index 0000000..9a0b3fd
--- /dev/null
+++ b/lib/widgets/totem-glow-button.c
@@ -0,0 +1,351 @@
+/*
+ * (C) Copyright 2007 Bastien Nocera <hadess hadess net>
+ *
+ * Glow code from libwnck/libwnck/tasklist.c:
+ * Copyright © 2001 Havoc Pennington
+ * Copyright © 2003 Kim Woelders
+ * Copyright © 2003 Red Hat, Inc.
+ *
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301  USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <math.h>
+#include <gtk/gtk.h>
+#include "totem-glow-button.h"
+
+#define FADE_OPACITY_DEFAULT 0.6
+#define ENTER_SPEEDUP_RATIO 0.4
+#define FADE_MAX_LOOPS 4
+
+struct _TotemGlowButton {
+	GtkButton parent;
+
+	gdouble glow_start_time;
+	gdouble glow_factor;
+
+	guint button_glow;
+
+	guint glow : 1;
+	guint anim_enabled : 1;
+	guint pointer_entered : 1;
+	/* Set when we don't want to play animation
+	 * anymore in pointer entered mode */
+	guint anim_finished :1;
+};
+
+static void totem_glow_button_set_timeout (TotemGlowButton *button, gboolean set_timeout);
+
+static GtkButtonClass *parent_class;
+
+G_DEFINE_TYPE (TotemGlowButton, totem_glow_button, GTK_TYPE_BUTTON);
+
+static gboolean
+totem_glow_button_glow (TotemGlowButton *button)
+{
+	GtkWidget *buttonw;
+	GTimeVal tv;
+	gdouble now;
+	gfloat fade_opacity, loop_time;
+
+	buttonw = GTK_WIDGET (button);
+
+	if (gtk_widget_get_realized (buttonw) == FALSE)
+		return TRUE;
+
+	if (button->anim_enabled != FALSE) {
+		g_get_current_time (&tv);
+		now = (tv.tv_sec * (1.0 * G_USEC_PER_SEC) +
+		       tv.tv_usec) / G_USEC_PER_SEC;
+
+		/* Hard-coded values */
+		fade_opacity = FADE_OPACITY_DEFAULT;
+		loop_time = 3.0;
+
+		if (button->glow_start_time <= G_MINDOUBLE) {
+			button->glow_start_time = now;
+			/* If the pointer entered, we want to start with 'dark' */
+			if (button->pointer_entered != FALSE) {
+				button->glow_start_time -= loop_time / 4.0;
+			}
+		}
+
+		/* Timing for mouse hover animation
+		   [light]......[dark]......[light]......[dark]...
+		   {mouse hover event}
+		   [dark]..[light]..[dark]..[light]
+		   {mouse leave event}
+		   [light]......[dark]......[light]......[dark]
+		*/
+		if (button->pointer_entered != FALSE) {
+			/* pointer entered animation should be twice as fast */
+			loop_time *= ENTER_SPEEDUP_RATIO;
+		}
+		if ((now - button->glow_start_time) > loop_time * FADE_MAX_LOOPS) {
+			button->anim_finished = TRUE;
+			button->glow_factor = FADE_OPACITY_DEFAULT * 0.5;
+		} else {
+			button->glow_factor = fade_opacity * (0.5 - 0.5 * cos ((now - button->glow_start_time) * M_PI * 2.0 / loop_time));
+		}
+	} else {
+		button->glow_factor = FADE_OPACITY_DEFAULT * 0.5;
+	}
+
+	gtk_widget_queue_draw (GTK_WIDGET (button));
+
+	if (button->anim_finished != FALSE)
+		totem_glow_button_set_timeout (button, FALSE);
+
+	return button->anim_enabled;
+}
+
+static void
+totem_glow_button_clear_glow_start_timeout_id (TotemGlowButton *button)
+{
+	button->button_glow = 0;
+}
+
+static gboolean
+totem_glow_button_draw (GtkWidget *widget,
+			cairo_t   *cr,
+			gpointer   user_data)
+{
+	TotemGlowButton *button;
+	GtkStyleContext *context;
+	GtkAllocation allocation, child_allocation;
+	gint width, height;
+	GtkWidget *child;
+	GdkRGBA acolor;
+
+	button = TOTEM_GLOW_BUTTON (widget);
+
+	if (button->glow_factor == 0.0)
+		return FALSE;
+
+	context = gtk_widget_get_style_context (widget);
+
+	/* push a translucent overlay to paint to, so we can blend later */
+	cairo_push_group_with_content (cr, CAIRO_CONTENT_COLOR_ALPHA);
+
+	gtk_widget_get_allocation (widget, &allocation);
+
+	width = allocation.width;
+	height = allocation.height;
+
+	/* Draw a rectangle with bg[SELECTED] */
+	gtk_style_context_save (context);
+	gtk_style_context_add_class (context, "button");
+	gtk_style_context_set_state (context, GTK_STATE_SELECTED);
+	gtk_style_context_get_background_color (context, GTK_STATE_SELECTED, &acolor);
+	gdk_cairo_set_source_rgba (cr, &acolor);
+	gtk_render_background (context, cr, 0, 0, width, height);
+	gtk_style_context_restore (context);
+
+	/* then the image */
+	cairo_save (cr);
+	child = gtk_bin_get_child (GTK_BIN (button));
+	gtk_widget_get_allocation (child, &child_allocation);
+	cairo_translate (cr,
+			 child_allocation.x - allocation.x,
+			 child_allocation.y - allocation.y);
+	gtk_widget_draw (gtk_bin_get_child (GTK_BIN (button)), cr);
+	cairo_restore (cr);
+
+	/* finally blend it */
+	cairo_pop_group_to_source (cr);
+	cairo_paint_with_alpha (cr, button->glow_factor);
+
+	return FALSE;
+}
+
+static void
+totem_glow_button_map (GtkWidget *buttonw)
+{
+	TotemGlowButton *button;
+
+	(* GTK_WIDGET_CLASS (parent_class)->map) (buttonw);
+
+	button = TOTEM_GLOW_BUTTON (buttonw);
+
+	if (button->glow != FALSE && button->button_glow == 0) {
+		totem_glow_button_set_glow (button, TRUE);
+	}
+}
+
+static void
+totem_glow_button_unmap (GtkWidget *buttonw)
+{
+	TotemGlowButton *button;
+
+	button = TOTEM_GLOW_BUTTON (buttonw);
+
+	if (button->button_glow > 0) {
+		g_source_remove (button->button_glow);
+		button->button_glow = 0;
+	}
+
+	(* GTK_WIDGET_CLASS (parent_class)->unmap) (buttonw);
+}
+
+static void
+totem_glow_button_enter (GtkButton *buttonw)
+{
+	TotemGlowButton *button;
+
+	button = TOTEM_GLOW_BUTTON (buttonw);
+
+	(* GTK_BUTTON_CLASS (parent_class)->enter) (buttonw);
+
+	button->pointer_entered = TRUE;
+	button->anim_finished = FALSE;
+	button->glow_start_time = G_MINDOUBLE;
+	totem_glow_button_set_timeout (button, FALSE);
+}
+
+static void
+totem_glow_button_leave (GtkButton *buttonw)
+{
+	TotemGlowButton *button;
+
+	button = TOTEM_GLOW_BUTTON (buttonw);
+
+	(* GTK_BUTTON_CLASS (parent_class)->leave) (buttonw);
+
+	button->pointer_entered = FALSE;
+	button->glow_start_time = G_MINDOUBLE;
+	button->anim_finished = FALSE;
+	if (button->glow != FALSE)
+		totem_glow_button_set_timeout (button, TRUE);
+}
+
+static void
+totem_glow_button_finalize (GObject *object)
+{
+	TotemGlowButton *button = TOTEM_GLOW_BUTTON (object);
+
+	totem_glow_button_set_glow (button, FALSE);
+
+	G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static void
+totem_glow_button_class_init (TotemGlowButtonClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
+	GtkButtonClass *button_class = GTK_BUTTON_CLASS (klass);
+
+	parent_class = g_type_class_peek_parent (klass);
+
+	object_class->finalize = totem_glow_button_finalize;
+	/* Note that we don't use a draw here because we
+	 * want to modify what the button will draw by itself */
+	widget_class->map = totem_glow_button_map;
+	widget_class->unmap = totem_glow_button_unmap;
+	button_class->enter = totem_glow_button_enter;
+	button_class->leave = totem_glow_button_leave;
+}
+
+static void
+totem_glow_button_init (TotemGlowButton *button)
+{
+	button->glow_start_time = 0.0;
+	button->button_glow = 0;
+	button->glow_factor = 0.0;
+
+	g_signal_connect_object (button, "draw",
+				 G_CALLBACK (totem_glow_button_draw),
+				 G_OBJECT (button),
+				 G_CONNECT_AFTER);
+}
+
+GtkWidget *
+totem_glow_button_new (void)
+{
+	return g_object_new (TOTEM_TYPE_GLOW_BUTTON, NULL);
+}
+
+/* We can only add a timeout once, we assert that, though
+ * calling it multiple times to disable the animation is fine */
+static void
+totem_glow_button_set_timeout (TotemGlowButton *button, gboolean set_timeout)
+{
+	if (set_timeout != FALSE) {
+		if (button->button_glow > 0)
+			return;
+
+		button->glow_start_time = 0.0;
+
+		/* The animation doesn't speed up or slow down based on the
+		 * timeout value, but instead will just appear smoother or
+		 * choppier.
+		 */
+		button->button_glow =
+			g_timeout_add_full (G_PRIORITY_DEFAULT_IDLE,
+					    100,
+					    (GSourceFunc) totem_glow_button_glow, button,
+					    (GDestroyNotify) totem_glow_button_clear_glow_start_timeout_id);
+	} else {
+		if (button->button_glow > 0) {
+			g_source_remove (button->button_glow);
+			button->button_glow = 0;
+		}
+		button->glow_factor = 0.0;
+		gtk_widget_queue_draw (GTK_WIDGET (button));
+	}
+}
+
+void
+totem_glow_button_set_glow (TotemGlowButton *button, gboolean glow)
+{
+	GtkSettings *settings;
+	gboolean anim_enabled;
+
+	g_return_if_fail (TOTEM_IS_GLOW_BUTTON (button));
+
+	if (gtk_widget_get_mapped (GTK_WIDGET (button)) == FALSE
+	    && glow != FALSE) {
+		button->glow = glow;
+		return;
+	}
+
+	settings = gtk_settings_get_for_screen
+		(gtk_widget_get_screen (GTK_WIDGET (button)));
+	g_object_get (G_OBJECT (settings),
+		      "gtk-enable-animations", &anim_enabled,
+		      NULL);
+	button->anim_enabled = anim_enabled;
+
+	if (glow == FALSE && button->button_glow == 0 && button->anim_enabled != FALSE)
+		return;
+	if (glow != FALSE && button->button_glow != 0)
+		return;
+
+	button->glow = glow;
+
+	totem_glow_button_set_timeout (button, glow);
+}
+
+gboolean
+totem_glow_button_get_glow (TotemGlowButton *button)
+{
+	return button->glow != FALSE;
+}
+
diff --git a/lib/widgets/totem-glow-button.h b/lib/widgets/totem-glow-button.h
new file mode 100644
index 0000000..138f8c4
--- /dev/null
+++ b/lib/widgets/totem-glow-button.h
@@ -0,0 +1,52 @@
+/*
+ * (C) Copyright 2007 Bastien Nocera <hadess hadess net>
+ *
+ * Glow code from libwnck/libwnck/tasklist.c:
+ * Copyright © 2001 Havoc Pennington
+ * Copyright © 2003 Kim Woelders
+ * Copyright © 2003 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301  USA.
+ */
+
+#ifndef __TOTEM_GLOW_BUTTON_H__
+#define __TOTEM_GLOW_BUTTON_H__
+
+#include <gtk/gtk.h>
+
+G_BEGIN_DECLS
+
+#define TOTEM_TYPE_GLOW_BUTTON     (totem_glow_button_get_type ())
+#define TOTEM_GLOW_BUTTON(obj)     (G_TYPE_CHECK_INSTANCE_CAST ((obj), TOTEM_TYPE_GLOW_BUTTON, TotemGlowButton))
+#define TOTEM_IS_GLOW_BUTTON(obj)  (G_TYPE_CHECK_INSTANCE_TYPE ((obj), TOTEM_TYPE_GLOW_BUTTON))
+
+typedef struct _TotemGlowButton TotemGlowButton;
+
+typedef struct _TotemGlowButtonClass {
+  GtkButtonClass parent_class;
+
+  gpointer __bla[4];
+} TotemGlowButtonClass;
+
+GType		totem_glow_button_get_type	(void) G_GNUC_CONST;
+
+GtkWidget *	totem_glow_button_new		(void);
+void		totem_glow_button_set_glow	(TotemGlowButton *button, gboolean glow);
+gboolean	totem_glow_button_get_glow	(TotemGlowButton *button);
+
+G_END_DECLS
+
+#endif /* __TOTEM_GLOW_BUTTON_H__ */