mutter/clutter/clutter-desaturate-effect.c
Emmanuele Bassi 77ec8774a0 WARNING: Massive revert commit
Revert all the work that happened on the master branch.

Sadly, this is the only way to merge the current development branch back
into master.

It is now abundantly clear that I merged the 1.99 branch far too soon,
and that Clutter 2.0 won't happen any time soon, if at all.

Since having the development happen on a separate branch throws a lot of
people into confusion, let's undo the clutter-1.99 → master merge, and
move back the development of Clutter to the master branch.

In order to do so, we need to do some surgery to the Git repository.

First, we do a massive revert in a single commit of all that happened
since the switch to 1.99 and the API version bump done with the
89a2862b05 commit. The history is too long
to be reverted commit by commit without being extremely messy.
2015-01-03 20:34:20 +00:00

383 lines
11 KiB
C

/*
* 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 <http://www.gnu.org/licenses/>.
*
* Author:
* Emmanuele Bassi <ebassi@linux.intel.com>
*/
/**
* 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 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
#define CLUTTER_ENABLE_EXPERIMENTAL_API
#include <math.h>
#include "clutter-desaturate-effect.h"
#include "cogl/cogl.h"
#include "clutter-debug.h"
#include "clutter-enum-types.h"
#include "clutter-offscreen-effect.h"
#include "clutter-private.h"
struct _ClutterDesaturateEffect
{
ClutterOffscreenEffect parent_instance;
/* the desaturation factor, also known as "strength" */
gdouble factor;
gint factor_uniform;
gint tex_width;
gint tex_height;
CoglPipeline *pipeline;
};
struct _ClutterDesaturateEffectClass
{
ClutterOffscreenEffectClass parent_class;
CoglPipeline *base_pipeline;
};
/* 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_declarations =
"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";
static const gchar *desaturate_glsl_source =
" cogl_color_out.rgb = desaturate (cogl_color_out.rgb, factor);\n";
enum
{
PROP_0,
PROP_FACTOR,
PROP_LAST
};
static GParamSpec *obj_props[PROP_LAST];
G_DEFINE_TYPE (ClutterDesaturateEffect,
clutter_desaturate_effect,
CLUTTER_TYPE_OFFSCREEN_EFFECT);
static gboolean
clutter_desaturate_effect_pre_paint (ClutterEffect *effect)
{
ClutterDesaturateEffect *self = CLUTTER_DESATURATE_EFFECT (effect);
ClutterEffectClass *parent_class;
if (!clutter_actor_meta_get_enabled (CLUTTER_ACTOR_META (effect)))
return FALSE;
if (!clutter_feature_available (CLUTTER_FEATURE_SHADERS_GLSL))
{
/* if we don't have support for GLSL shaders then we
* forcibly disable the ActorMeta
*/
g_warning ("Unable to use the ShaderEffect: the graphics hardware "
"or the current GL driver does not implement support "
"for the GLSL shading language.");
clutter_actor_meta_set_enabled (CLUTTER_ACTOR_META (effect), FALSE);
return FALSE;
}
parent_class = CLUTTER_EFFECT_CLASS (clutter_desaturate_effect_parent_class);
if (parent_class->pre_paint (effect))
{
ClutterOffscreenEffect *offscreen_effect =
CLUTTER_OFFSCREEN_EFFECT (effect);
CoglHandle texture;
texture = clutter_offscreen_effect_get_texture (offscreen_effect);
self->tex_width = cogl_texture_get_width (texture);
self->tex_height = cogl_texture_get_height (texture);
cogl_pipeline_set_layer_texture (self->pipeline, 0, texture);
return TRUE;
}
else
return FALSE;
}
static void
clutter_desaturate_effect_paint_target (ClutterOffscreenEffect *effect)
{
ClutterDesaturateEffect *self = CLUTTER_DESATURATE_EFFECT (effect);
ClutterActor *actor;
CoglHandle texture;
guint8 paint_opacity;
texture = clutter_offscreen_effect_get_texture (effect);
cogl_pipeline_set_layer_texture (self->pipeline, 0, texture);
actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (effect));
paint_opacity = clutter_actor_get_paint_opacity (actor);
cogl_pipeline_set_color4ub (self->pipeline,
paint_opacity,
paint_opacity,
paint_opacity,
paint_opacity);
cogl_push_source (self->pipeline);
cogl_rectangle (0, 0,
cogl_texture_get_width (texture),
cogl_texture_get_height (texture));
cogl_pop_source ();
}
static void
clutter_desaturate_effect_dispose (GObject *gobject)
{
ClutterDesaturateEffect *self = CLUTTER_DESATURATE_EFFECT (gobject);
if (self->pipeline != NULL)
{
cogl_object_unref (self->pipeline);
self->pipeline = NULL;
}
G_OBJECT_CLASS (clutter_desaturate_effect_parent_class)->dispose (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
update_factor_uniform (ClutterDesaturateEffect *self)
{
if (self->factor_uniform > -1)
cogl_pipeline_set_uniform_1f (self->pipeline,
self->factor_uniform,
self->factor);
}
static void
clutter_desaturate_effect_class_init (ClutterDesaturateEffectClass *klass)
{
ClutterEffectClass *effect_class = CLUTTER_EFFECT_CLASS (klass);
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
ClutterOffscreenEffectClass *offscreen_class;
offscreen_class = CLUTTER_OFFSCREEN_EFFECT_CLASS (klass);
offscreen_class->paint_target = clutter_desaturate_effect_paint_target;
effect_class->pre_paint = clutter_desaturate_effect_pre_paint;
/**
* ClutterDesaturateEffect:factor:
*
* The desaturation factor, between 0.0 (no desaturation) and 1.0 (full
* desaturation).
*
* Since: 1.4
*/
obj_props[PROP_FACTOR] =
g_param_spec_double ("factor",
P_("Factor"),
P_("The desaturation factor"),
0.0, 1.0,
1.0,
CLUTTER_PARAM_READWRITE);
gobject_class->dispose = clutter_desaturate_effect_dispose;
gobject_class->set_property = clutter_desaturate_effect_set_property;
gobject_class->get_property = clutter_desaturate_effect_get_property;
g_object_class_install_properties (gobject_class, PROP_LAST, obj_props);
}
static void
clutter_desaturate_effect_init (ClutterDesaturateEffect *self)
{
ClutterDesaturateEffectClass *klass = CLUTTER_DESATURATE_EFFECT_GET_CLASS (self);
if (G_UNLIKELY (klass->base_pipeline == NULL))
{
CoglContext *ctx =
clutter_backend_get_cogl_context (clutter_get_default_backend ());
CoglSnippet *snippet;
klass->base_pipeline = cogl_pipeline_new (ctx);
snippet = cogl_snippet_new (COGL_SNIPPET_HOOK_FRAGMENT,
desaturate_glsl_declarations,
desaturate_glsl_source);
cogl_pipeline_add_snippet (klass->base_pipeline, snippet);
cogl_object_unref (snippet);
cogl_pipeline_set_layer_null_texture (klass->base_pipeline,
0, /* layer number */
COGL_TEXTURE_TYPE_2D);
}
self->pipeline = cogl_pipeline_copy (klass->base_pipeline);
self->factor_uniform =
cogl_pipeline_get_uniform_location (self->pipeline, "factor");
self->factor = 1.0;
update_factor_uniform (self);
}
/**
* clutter_desaturate_effect_new:
* @factor: the desaturation factor, between 0.0 and 1.0
*
* Creates a new #ClutterDesaturateEffect to be used with
* clutter_actor_add_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;
update_factor_uniform (effect);
clutter_effect_queue_repaint (CLUTTER_EFFECT (effect));
g_object_notify_by_pspec (G_OBJECT (effect), obj_props[PROP_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;
}