mutter/clutter/clutter-colorize-effect.c
Emmanuele Bassi 0e9a1dee6d shader-effect: Simplify setting the shader source
Sub-classes of ShaderEffect currently have to get the handle for the
Cogl shader and call cogl_shader_source(); this makes it awkward to
implement a ShaderEffect, and it exposes handles and Cogl API that we
might want to change in the future.

We should provide a ClutterShaderEffect method that allows to (safely)
set the shader source at the right time for sub-classes to use.
2010-06-03 14:10:55 +01:00

284 lines
7.9 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
*
* #ClutterColorizeEffect is a sub-class of #ClutterEffect that
* colorizes an actor with the given tint.
*
* #ClutterColorizeEffect uses the programmable pipeline of the GPU
* so it is only available on graphics hardware that supports this
* feature.
*
* #ClutterColorizeEffect is available since Clutter 1.4
*/
#define CLUTTER_COLORIZE_EFFECT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_COLORIZE_EFFECT, ClutterColorizeEffectClass))
#define CLUTTER_IS_COLORIZE_EFFECT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_COLORIZE_EFFECT))
#define CLUTTER_COLORIZE_EFFECT_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_COLORIZE_EFFECT, ClutterColorizeEffectClass))
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "clutter-colorize-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 _ClutterColorizeEffectClass ClutterColorizeEffectClass;
struct _ClutterColorizeEffect
{
ClutterShaderEffect parent_instance;
/* a back pointer to our actor, so that we can query it */
ClutterActor *actor;
/* the tint of the colorization */
ClutterColor tint;
};
struct _ClutterColorizeEffectClass
{
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 *colorize_glsl_shader =
"uniform sampler2D tex;\n"
"uniform vec3 tint;\n"
"\n"
"void main ()\n"
"{\n"
" vec4 color = gl_Color * texture2D (tex, vec2 (gl_TexCoord[0].xy));\n"
" float gray = dot (color.rgb, vec3 (0.299, 0.587, 0.114));\n"
" gl_FragColor = vec4 (gray * tint, color.a);\n"
"}\n";
/* a lame sepia */
static const ClutterColor default_tint = { 255, 204, 153, 255 };
enum
{
PROP_0,
PROP_TINT
};
G_DEFINE_TYPE (ClutterColorizeEffect,
clutter_colorize_effect,
CLUTTER_TYPE_SHADER_EFFECT);
static gboolean
clutter_colorize_effect_pre_paint (ClutterEffect *effect)
{
ClutterColorizeEffect *self = CLUTTER_COLORIZE_EFFECT (effect);
ClutterShaderEffect *shader_effect;
ClutterEffectClass *parent_class;
float tint_r, tint_g, tint_b;
if (!clutter_actor_meta_get_enabled (CLUTTER_ACTOR_META (effect)))
return FALSE;
shader_effect = CLUTTER_SHADER_EFFECT (effect);
clutter_shader_effect_set_shader_source (shader_effect, colorize_glsl_shader);
/* we want normalized values here */
tint_r = self->tint.red / 255.0f;
tint_g = self->tint.green / 255.0f;
tint_b = self->tint.blue / 255.0f;
/* 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,
"tint",
G_TYPE_FLOAT, 3,
tint_r,
tint_g,
tint_b);
parent_class = CLUTTER_EFFECT_CLASS (clutter_colorize_effect_parent_class);
return parent_class->pre_paint (effect);
}
static void
clutter_colorize_effect_finalize (GObject *gobject)
{
G_OBJECT_CLASS (clutter_colorize_effect_parent_class)->finalize (gobject);
}
static void
clutter_colorize_effect_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
ClutterColorizeEffect *effect = CLUTTER_COLORIZE_EFFECT (gobject);
switch (prop_id)
{
case PROP_TINT:
clutter_colorize_effect_set_tint (effect,
clutter_value_get_color (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_colorize_effect_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterColorizeEffect *effect = CLUTTER_COLORIZE_EFFECT (gobject);
switch (prop_id)
{
case PROP_TINT:
clutter_value_set_color (value, &effect->tint);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_colorize_effect_class_init (ClutterColorizeEffectClass *klass)
{
ClutterEffectClass *effect_class = CLUTTER_EFFECT_CLASS (klass);
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GParamSpec *pspec;
effect_class->pre_paint = clutter_colorize_effect_pre_paint;
gobject_class->set_property = clutter_colorize_effect_set_property;
gobject_class->get_property = clutter_colorize_effect_get_property;
gobject_class->finalize = clutter_colorize_effect_finalize;
/**
* ClutterColorizeEffect:tint:
*
* The tint to apply to the actor
*
* Since: 1.4
*/
pspec = clutter_param_spec_color ("tint",
"Tint",
"The tint to apply",
&default_tint,
CLUTTER_PARAM_READWRITE);
g_object_class_install_property (gobject_class, PROP_TINT, pspec);
}
static void
clutter_colorize_effect_init (ClutterColorizeEffect *self)
{
self->tint = default_tint;
}
/**
* clutter_colorize_effect_new:
* @tint: the color to be used
*
* Creates a new #ClutterColorizeEffect to be used with
* clutter_actor_set_effect()
*
* Return value: the newly created #ClutterColorizeEffect or %NULL
*
* Since: 1.4
*/
ClutterEffect *
clutter_colorize_effect_new (const ClutterColor *tint)
{
return g_object_new (CLUTTER_TYPE_COLORIZE_EFFECT,
"tint", tint,
NULL);
}
/**
* clutter_colorize_effect_set_tint:
* @effect: a #ClutterColorizeEffect
* @tint: the color to be used
*
* Sets the tint to be used when colorizing
*
* Since: 1.4
*/
void
clutter_colorize_effect_set_tint (ClutterColorizeEffect *effect,
const ClutterColor *tint)
{
g_return_if_fail (CLUTTER_IS_COLORIZE_EFFECT (effect));
effect->tint = *tint;
if (effect->actor != NULL)
clutter_actor_queue_redraw (effect->actor);
g_object_notify (G_OBJECT (effect), "tint");
}
/**
* clutter_colorize_effect_get_tint:
* @effect: a #ClutterColorizeEffect
* @tint: (out): return location for the color used
*
* Retrieves the tint used by @effect
*
* Since: 1.4
*/
void
clutter_colorize_effect_get_tint (ClutterColorizeEffect *effect,
ClutterColor *tint)
{
g_return_if_fail (CLUTTER_IS_COLORIZE_EFFECT (effect));
g_return_if_fail (tint != NULL);
*tint = effect->tint;
}