diff --git a/clutter/Makefile.am b/clutter/Makefile.am
index fa82005ad..718de5568 100644
--- a/clutter/Makefile.am
+++ b/clutter/Makefile.am
@@ -95,6 +95,7 @@ source_h = \
$(srcdir)/clutter-constraint.h \
$(srcdir)/clutter-container.h \
$(srcdir)/clutter-deprecated.h \
+ $(srcdir)/clutter-desaturate-effect.h \
$(srcdir)/clutter-device-manager.h \
$(srcdir)/clutter-drag-action.h \
$(srcdir)/clutter-effect.h \
@@ -180,6 +181,7 @@ source_c = \
$(srcdir)/clutter-color.c \
$(srcdir)/clutter-constraint.c \
$(srcdir)/clutter-container.c \
+ $(srcdir)/clutter-desaturate-effect.c \
$(srcdir)/clutter-device-manager.c \
$(srcdir)/clutter-drag-action.c \
$(srcdir)/clutter-effect.c \
diff --git a/clutter/clutter-desaturate-effect.c b/clutter/clutter-desaturate-effect.c
new file mode 100644
index 000000000..1a81e370d
--- /dev/null
+++ b/clutter/clutter-desaturate-effect.c
@@ -0,0 +1,309 @@
+/*
+ * Clutter.
+ *
+ * An OpenGL based 'interactive canvas' library.
+ *
+ * Copyright (C) 2010 Intel Corporation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see .
+ *
+ * Author:
+ * Emmanuele Bassi
+ */
+
+/**
+ * SECTION:clutter-desaturate-effect
+ * @short_description: A desaturation effect
+ * @see_also: #ClutterEffect, #ClutterOffscreenEffect
+ *
+ * #ClutterDesaturateEffect is a sub-class of #ClutterEffect that
+ * desaturates the color of an actor and its contents. The strenght
+ * of the desaturation effect is controllable and animatable through
+ * the #ClutterDesaturateEffect:factor property.
+ *
+ * #ClutterDesaturateEffect uses the programmable pipeline of the GPU
+ * so it is only available on graphics hardware that supports this
+ * feature.
+ *
+ * #ClutterDesaturateEffect is available since Clutter 1.4
+ */
+
+#define CLUTTER_DESATURATE_EFFECT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_DESATURATE_EFFECT, ClutterDesaturateEffectClass))
+#define CLUTTER_IS_DESATURATE_EFFECT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_DESATURATE_EFFECT))
+#define CLUTTER_DESATURATE_EFFECT_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_DESATURATE_EFFECT, ClutterDesaturateEffectClass))
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "clutter-desaturate-effect.h"
+
+#include "cogl/cogl.h"
+
+#include "clutter-debug.h"
+#include "clutter-enum-types.h"
+#include "clutter-private.h"
+#include "clutter-shader-effect.h"
+
+typedef struct _ClutterDesaturateEffectClass ClutterDesaturateEffectClass;
+
+struct _ClutterDesaturateEffect
+{
+ ClutterShaderEffect parent_instance;
+
+ /* a back pointer to our actor, so that we can query it */
+ ClutterActor *actor;
+
+ /* the desaturation factor, also known as "strength" */
+ gdouble factor;
+
+ guint source_set : 1;
+};
+
+struct _ClutterDesaturateEffectClass
+{
+ ClutterShaderEffectClass parent_class;
+};
+
+/* the magic gray vec3 has been taken from the NTSC conversion weights
+ * as defined by:
+ *
+ * "OpenGL Superbible, 4th edition"
+ * -- Richard S. Wright Jr, Benjamin Lipchak, Nicholas Haemel
+ * Addison-Wesley
+ */
+static const gchar *desaturate_glsl_shader =
+"uniform sampler2D tex;\n"
+"uniform float factor;\n"
+"\n"
+"vec3 desaturate (const vec3 color, const float desaturation)\n"
+"{\n"
+" const vec3 gray_conv = vec3 (0.299, 0.587, 0.114);\n"
+" vec3 gray = vec3 (dot (gray_conv, color));\n"
+" return vec3 (mix (color.rgb, gray, desaturation));\n"
+"}\n"
+"\n"
+"void main ()\n"
+"{\n"
+" vec4 color = gl_Color * texture2D (tex, vec2 (gl_TexCoord[0].xy));\n"
+" color.rgb = desaturate (color.rgb, factor);\n"
+" gl_FragColor = color;\n"
+"}\n";
+
+enum
+{
+ PROP_0,
+
+ PROP_FACTOR
+};
+
+G_DEFINE_TYPE (ClutterDesaturateEffect,
+ clutter_desaturate_effect,
+ CLUTTER_TYPE_SHADER_EFFECT);
+
+static gboolean
+clutter_desaturate_effect_pre_paint (ClutterEffect *effect)
+{
+ ClutterDesaturateEffect *self = CLUTTER_DESATURATE_EFFECT (effect);
+ ClutterShaderEffect *shader_effect;
+ ClutterEffectClass *parent_class;
+ float factor;
+
+ if (!clutter_actor_meta_get_enabled (CLUTTER_ACTOR_META (effect)))
+ return FALSE;
+
+ self->actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (effect));
+ if (self->actor == NULL)
+ return FALSE;
+
+ shader_effect = CLUTTER_SHADER_EFFECT (effect);
+
+ if (!self->source_set)
+ {
+ CoglHandle shader;
+
+ /* get the CoglShader handle to set the source */
+ shader = clutter_shader_effect_get_shader (shader_effect);
+ if (shader == COGL_INVALID_HANDLE)
+ return FALSE;
+
+ cogl_shader_source (shader, desaturate_glsl_shader);
+ self->source_set = TRUE;
+ }
+
+ factor = (float) self->factor;
+
+ /* bind the uniforms to the factor property */
+ clutter_shader_effect_set_uniform (shader_effect,
+ "tex",
+ G_TYPE_INT, 1,
+ 0);
+ clutter_shader_effect_set_uniform (shader_effect,
+ "factor",
+ G_TYPE_FLOAT, 1,
+ factor);
+
+ parent_class = CLUTTER_EFFECT_CLASS (clutter_desaturate_effect_parent_class);
+ return parent_class->pre_paint (effect);
+}
+
+static void
+clutter_desaturate_effect_finalize (GObject *gobject)
+{
+ G_OBJECT_CLASS (clutter_desaturate_effect_parent_class)->finalize (gobject);
+}
+
+static void
+clutter_desaturate_effect_set_property (GObject *gobject,
+ guint prop_id,
+ const GValue *value,
+ GParamSpec *pspec)
+{
+ ClutterDesaturateEffect *effect = CLUTTER_DESATURATE_EFFECT (gobject);
+
+ switch (prop_id)
+ {
+ case PROP_FACTOR:
+ clutter_desaturate_effect_set_factor (effect,
+ g_value_get_double (value));
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+clutter_desaturate_effect_get_property (GObject *gobject,
+ guint prop_id,
+ GValue *value,
+ GParamSpec *pspec)
+{
+ ClutterDesaturateEffect *effect = CLUTTER_DESATURATE_EFFECT (gobject);
+
+ switch (prop_id)
+ {
+ case PROP_FACTOR:
+ g_value_set_double (value, effect->factor);
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+clutter_desaturate_effect_class_init (ClutterDesaturateEffectClass *klass)
+{
+ ClutterEffectClass *effect_class = CLUTTER_EFFECT_CLASS (klass);
+ GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+ GParamSpec *pspec;
+
+ effect_class->pre_paint = clutter_desaturate_effect_pre_paint;
+
+ gobject_class->set_property = clutter_desaturate_effect_set_property;
+ gobject_class->get_property = clutter_desaturate_effect_get_property;
+ gobject_class->finalize = clutter_desaturate_effect_finalize;
+
+ /**
+ * ClutterDesaturateEffect:factor:
+ *
+ * The desaturation factor, between 0.0 (no desaturation) and 1.0 (full
+ * desaturation).
+ *
+ * Since: 1.4
+ */
+ pspec = g_param_spec_double ("factor",
+ "Factor",
+ "The desaturation factor",
+ 0.0, 1.0,
+ 1.0,
+ CLUTTER_PARAM_READWRITE);
+ g_object_class_install_property (gobject_class, PROP_FACTOR, pspec);
+}
+
+static void
+clutter_desaturate_effect_init (ClutterDesaturateEffect *self)
+{
+ self->factor = 1.0;
+}
+
+/**
+ * clutter_desaturate_effect_new:
+ * @factor: the desaturation factor, between 0.0 and 1.0
+ *
+ * Creates a new #ClutterDesaturateEffect to be used with
+ * clutter_actor_set_effect()
+ *
+ * Return value: the newly created #ClutterDesaturateEffect or %NULL
+ *
+ * Since: 1.4
+ */
+ClutterEffect *
+clutter_desaturate_effect_new (gdouble factor)
+{
+ g_return_val_if_fail (factor >= 0.0 && factor <= 1.0, NULL);
+
+ return g_object_new (CLUTTER_TYPE_DESATURATE_EFFECT,
+ "factor", factor,
+ NULL);
+}
+
+/**
+ * clutter_desaturate_effect_set_factor:
+ * @effect: a #ClutterDesaturateEffect
+ * @factor: the desaturation factor, between 0.0 and 1.0
+ *
+ * Sets the desaturation factor for @effect, with 0.0 being "do not desaturate"
+ * and 1.0 being "fully desaturate"
+ *
+ * Since: 1.4
+ */
+void
+clutter_desaturate_effect_set_factor (ClutterDesaturateEffect *effect,
+ gdouble factor)
+{
+ g_return_if_fail (CLUTTER_IS_DESATURATE_EFFECT (effect));
+ g_return_if_fail (factor >= 0.0 && factor <= 1.0);
+
+ if (fabsf (effect->factor - factor) >= 0.00001)
+ {
+ effect->factor = factor;
+
+ if (effect->actor != NULL)
+ clutter_actor_queue_redraw (effect->actor);
+
+ g_object_notify (G_OBJECT (effect), "factor");
+ }
+}
+
+/**
+ * clutter_desaturate_effect_get_factor:
+ * @effect: a #ClutterDesaturateEffect
+ *
+ * Retrieves the desaturation factor of @effect
+ *
+ * Return value: the desaturation factor
+ *
+ * Since: 1.4
+ */
+gdouble
+clutter_desaturate_effect_get_factor (ClutterDesaturateEffect *effect)
+{
+ g_return_val_if_fail (CLUTTER_IS_DESATURATE_EFFECT (effect), 0.0);
+
+ return effect->factor;
+}
diff --git a/clutter/clutter-desaturate-effect.h b/clutter/clutter-desaturate-effect.h
new file mode 100644
index 000000000..7c51a5715
--- /dev/null
+++ b/clutter/clutter-desaturate-effect.h
@@ -0,0 +1,60 @@
+/*
+ * Clutter.
+ *
+ * An OpenGL based 'interactive canvas' library.
+ *
+ * Copyright (C) 2010 Intel Corporation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see .
+ *
+ * Author:
+ * Emmanuele Bassi
+ */
+
+#if !defined(__CLUTTER_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
+#error "Only can be included directly."
+#endif
+
+#ifndef __CLUTTER_DESATURATE_EFFECT_H__
+#define __CLUTTER_DESATURATE_EFFECT_H__
+
+#include
+
+G_BEGIN_DECLS
+
+#define CLUTTER_TYPE_DESATURATE_EFFECT (clutter_desaturate_effect_get_type ())
+#define CLUTTER_DESATURATE_EFFECT(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), CLUTTER_TYPE_DESATURATE_EFFECT, ClutterDesaturateEffect))
+#define CLUTTER_IS_DESATURATE_EFFECT(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CLUTTER_TYPE_DESATURATE_EFFECT))
+
+/**
+ * ClutterDesaturateEffect:
+ *
+ * ClutterDesaturateEffect is an opaque structure
+ * whose members cannot be directly accessed
+ *
+ * Since: 1.4
+ */
+typedef struct _ClutterDesaturateEffect ClutterDesaturateEffect;
+
+GType clutter_desaturate_effect_get_type (void) G_GNUC_CONST;
+
+ClutterEffect *clutter_desaturate_effect_new (gdouble factor);
+
+void clutter_desaturate_effect_set_factor (ClutterDesaturateEffect *effect,
+ gdouble factor);
+gdouble clutter_desaturate_effect_get_factor (ClutterDesaturateEffect *effect);
+
+G_END_DECLS
+
+#endif /* __CLUTTER_DESATURATE_EFFECT_H__ */
diff --git a/clutter/clutter.h b/clutter/clutter.h
index 1cdf0628d..e6a8da6c5 100644
--- a/clutter/clutter.h
+++ b/clutter/clutter.h
@@ -59,6 +59,7 @@
#include "clutter-color.h"
#include "clutter-constraint.h"
#include "clutter-container.h"
+#include "clutter-desaturate-effect.h"
#include "clutter-device-manager.h"
#include "clutter-drag-action.h"
#include "clutter-effect.h"
diff --git a/tests/interactive/test-rotate.c b/tests/interactive/test-rotate.c
index 2001090f5..60f85df96 100644
--- a/tests/interactive/test-rotate.c
+++ b/tests/interactive/test-rotate.c
@@ -35,7 +35,7 @@ test_rotate_main (int argc, char *argv[])
clutter_actor_set_position (hand, 240, 140);
clutter_actor_show (hand);
- clutter_container_add_actor (CLUTTER_CONTAINER (stage), hand);
+ clutter_actor_add_effect (hand, clutter_desaturate_effect_new (0.75));
label = clutter_text_new_with_text ("Mono 16",
"The Wonder\n"