/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2010-2012 Inclusive Design Research Centre, OCAD University.
*
* 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:
* Joseph Scheuhammer <clown@alum.mit.edu>
*/
/**
* SECTION:clutter-brightness-contrast-effect
* @short_description: Increase/decrease brightness and/or contrast of actor.
* @see_also: #ClutterEffect, #ClutterOffscreenEffect
*
* #ClutterBrightnessContrastEffect is a sub-class of #ClutterEffect that
* changes the overall brightness of a #ClutterActor.
*
* #ClutterBrightnessContrastEffect is available since Clutter 1.10
*/
#define CLUTTER_BRIGHTNESS_CONTRAST_EFFECT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_BRIGHTNESS_CONTRAST_EFFECT, ClutterBrightnessContrastEffectClass))
#define CLUTTER_IS_BRIGHTNESS_CONTRAST_EFFECT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_BRIGHTNESS_CONTRAST_EFFECT))
#define CLUTTER_BRIGHTNESS_CONTRAST_EFFECT_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_BRIGHTNESS_CONTRAST_EFFECT, ClutterBrightnessContrastEffectClass))
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <math.h>
#define CLUTTER_ENABLE_EXPERIMENTAL_API
#include "clutter-brightness-contrast-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 _ClutterBrightnessContrastEffect
{
ClutterOffscreenEffect parent_instance;
/* Brightness and contrast changes. */
gfloat brightness_red;
gfloat brightness_green;
gfloat brightness_blue;
gfloat contrast_red;
gfloat contrast_green;
gfloat contrast_blue;
gint brightness_multiplier_uniform;
gint brightness_offset_uniform;
gint contrast_uniform;
gint tex_width;
gint tex_height;
CoglPipeline *pipeline;
};
struct _ClutterBrightnessContrastEffectClass
{
ClutterOffscreenEffectClass parent_class;
CoglPipeline *base_pipeline;
};
/* Brightness effects in GLSL.
*/
static const gchar *brightness_contrast_decls =
"uniform vec3 brightness_multiplier;\n"
"uniform vec3 brightness_offset;\n"
"uniform vec3 contrast;\n";
static const gchar *brightness_contrast_source =
/* Apply the brightness. The brightness_offset is multiplied by the
alpha to keep the color pre-multiplied */
"cogl_color_out.rgb = (cogl_color_out.rgb * brightness_multiplier +\n"
" brightness_offset * cogl_color_out.a);\n"
/* Apply the contrast */
"cogl_color_out.rgb = ((cogl_color_out.rgb - 0.5 * cogl_color_out.a) *\n"
" contrast + 0.5 * cogl_color_out.a);\n";
static const ClutterColor no_brightness_change = { 0x7f, 0x7f, 0x7f, 0xff };
static const ClutterColor no_contrast_change = { 0x7f, 0x7f, 0x7f, 0xff };
static const gfloat no_change = 0.0f;
enum
{
PROP_0,
PROP_BRIGHTNESS,
PROP_CONTRAST,
PROP_LAST
};
static GParamSpec *obj_props[PROP_LAST];
G_DEFINE_TYPE (ClutterBrightnessContrastEffect,
clutter_brightness_contrast_effect,
CLUTTER_TYPE_OFFSCREEN_EFFECT);
static gboolean
will_have_no_effect (ClutterBrightnessContrastEffect *self)
{
return (self->brightness_red == no_change &&
self->brightness_green == no_change &&
self->brightness_blue == no_change &&
self->contrast_red == no_change &&
self->contrast_green == no_change &&
self->contrast_blue == no_change);
}
static gboolean
clutter_brightness_contrast_effect_pre_paint (ClutterEffect *effect)
{
ClutterBrightnessContrastEffect *self = CLUTTER_BRIGHTNESS_CONTRAST_EFFECT (effect);
ClutterEffectClass *parent_class;
if (!clutter_actor_meta_get_enabled (CLUTTER_ACTOR_META (effect)))
return FALSE;
if (will_have_no_effect (self))
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 ClutterBrightnessContrastEffect: the "
"graphics hardware or the current GL driver does not "
"implement support for the GLSL shading language. The "
"effect will be disabled.");
clutter_actor_meta_set_enabled (CLUTTER_ACTOR_META (effect), FALSE);
return FALSE;
}
parent_class =
CLUTTER_EFFECT_CLASS (clutter_brightness_contrast_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_brightness_contrast_effect_paint_target (ClutterOffscreenEffect *effect)
{
ClutterBrightnessContrastEffect *self = CLUTTER_BRIGHTNESS_CONTRAST_EFFECT (effect);
ClutterActor *actor;
guint8 paint_opacity;
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, self->tex_width, self->tex_height);
cogl_pop_source ();
}
static void
clutter_brightness_contrast_effect_dispose (GObject *gobject)
{
ClutterBrightnessContrastEffect *self = CLUTTER_BRIGHTNESS_CONTRAST_EFFECT (gobject);
if (self->pipeline != NULL)
{
cogl_object_unref (self->pipeline);
self->pipeline = NULL;
}
G_OBJECT_CLASS (clutter_brightness_contrast_effect_parent_class)->dispose (gobject);
}
static void
clutter_brightness_contrast_effect_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
ClutterBrightnessContrastEffect *effect = CLUTTER_BRIGHTNESS_CONTRAST_EFFECT (gobject);
switch (prop_id)
{
case PROP_BRIGHTNESS:
{
const ClutterColor *color = clutter_value_get_color (value);
clutter_brightness_contrast_effect_set_brightness_full (effect,
color->red / 127.0f - 1.0f,
color->green / 127.0f - 1.0f,
color->blue / 127.0f - 1.0f);
}
break;
case PROP_CONTRAST:
{
const ClutterColor *color = clutter_value_get_color (value);
clutter_brightness_contrast_effect_set_contrast_full (effect,
color->red / 127.0f - 1.0f,
color->green / 127.0f - 1.0f,
color->blue / 127.0f - 1.0f);
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_brightness_contrast_effect_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterBrightnessContrastEffect *effect = CLUTTER_BRIGHTNESS_CONTRAST_EFFECT (gobject);
ClutterColor color;
switch (prop_id)
{
case PROP_BRIGHTNESS:
{
color.red = (effect->brightness_red + 1.0f) * 127.0f;
color.green = (effect->brightness_green + 1.0f) * 127.0f;
color.blue = (effect->brightness_blue + 1.0f) * 127.0f;
color.alpha = 0xff;
clutter_value_set_color (value, &color);
}
break;
case PROP_CONTRAST:
{
color.red = (effect->contrast_red + 1.0f) * 127.0f;
color.green = (effect->contrast_green + 1.0f) * 127.0f;
color.blue = (effect->contrast_blue + 1.0f) * 127.0f;
color.alpha = 0xff;
clutter_value_set_color (value, &color);
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_brightness_contrast_effect_class_init (ClutterBrightnessContrastEffectClass *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_brightness_contrast_effect_paint_target;
effect_class->pre_paint = clutter_brightness_contrast_effect_pre_paint;
gobject_class->set_property = clutter_brightness_contrast_effect_set_property;
gobject_class->get_property = clutter_brightness_contrast_effect_get_property;
gobject_class->dispose = clutter_brightness_contrast_effect_dispose;
/**
* ClutterBrightnessContrastEffect:brightness:
*
* The brightness change to apply to the effect.
*
* This property uses a #ClutterColor to represent the changes to each
* color channel. The range is [ 0, 255 ], with 127 as the value used
* to indicate no change; values smaller than 127 indicate a decrease
* in brightness, and values larger than 127 indicate an increase in
* brightness.
*
* Since: 1.10
*/
obj_props[PROP_BRIGHTNESS] =
clutter_param_spec_color ("brightness",
P_("Brightness"),
P_("The brightness change to apply"),
&no_brightness_change,
CLUTTER_PARAM_READWRITE);
/**
* ClutterBrightnessContrastEffect:contrast:
*
* The contrast change to apply to the effect.
*
* This property uses a #ClutterColor to represent the changes to each
* color channel. The range is [ 0, 255 ], with 127 as the value used
* to indicate no change; values smaller than 127 indicate a decrease
* in contrast, and values larger than 127 indicate an increase in
* contrast.
*
* Since: 1.10
*/
obj_props[PROP_CONTRAST] =
clutter_param_spec_color ("contrast",
P_("Contrast"),
P_("The contrast change to apply"),
&no_contrast_change,
CLUTTER_PARAM_READWRITE);
g_object_class_install_properties (gobject_class, PROP_LAST, obj_props);
}
static void
get_brightness_values (gfloat value,
gfloat *multiplier,
gfloat *offset)
{
if (value < 0.0f)
{
*multiplier = 1.0f + value;
*offset = 0.0f;
}
else
{
*multiplier = 1.0f - value;
*offset = value;
}
}
static inline void
update_uniforms (ClutterBrightnessContrastEffect *self)
{
if (self->brightness_multiplier_uniform > -1 &&
self->brightness_offset_uniform > -1)
{
float brightness_multiplier[3];
float brightness_offset[3];
get_brightness_values (self->brightness_red,
brightness_multiplier + 0,
brightness_offset + 0);
get_brightness_values (self->brightness_green,
brightness_multiplier + 1,
brightness_offset + 1);
get_brightness_values (self->brightness_blue,
brightness_multiplier + 2,
brightness_offset + 2);
cogl_pipeline_set_uniform_float (self->pipeline,
self->brightness_multiplier_uniform,
3, /* n_components */
1, /* count */
brightness_multiplier);
cogl_pipeline_set_uniform_float (self->pipeline,
self->brightness_offset_uniform,
3, /* n_components */
1, /* count */
brightness_offset);
}
if (self->contrast_uniform > -1)
{
float contrast[3] = {
tan ((self->contrast_red + 1) * G_PI_4),
tan ((self->contrast_green + 1) * G_PI_4),
tan ((self->contrast_blue + 1) * G_PI_4)
};
cogl_pipeline_set_uniform_float (self->pipeline,
self->contrast_uniform,
3, /* n_components */
1, /* count */
contrast);
}
}
static void
clutter_brightness_contrast_effect_init (ClutterBrightnessContrastEffect *self)
{
ClutterBrightnessContrastEffectClass *klass;
self->brightness_red = no_change;
self->brightness_green = no_change;
self->brightness_blue = no_change;
self->contrast_red = no_change;
self->contrast_green = no_change;
self->contrast_blue = no_change;
klass = CLUTTER_BRIGHTNESS_CONTRAST_EFFECT_GET_CLASS (self);
if (G_UNLIKELY (klass->base_pipeline == NULL))
{
CoglSnippet *snippet;
CoglContext *ctx =
clutter_backend_get_cogl_context (clutter_get_default_backend ());
klass->base_pipeline = cogl_pipeline_new (ctx);
snippet = cogl_snippet_new (COGL_SNIPPET_HOOK_FRAGMENT,
brightness_contrast_decls,
brightness_contrast_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->brightness_multiplier_uniform =
cogl_pipeline_get_uniform_location (self->pipeline,
"brightness_multiplier");
self->brightness_offset_uniform =
cogl_pipeline_get_uniform_location (self->pipeline,
"brightness_offset");
self->contrast_uniform =
cogl_pipeline_get_uniform_location (self->pipeline, "contrast");
update_uniforms (self);
}
/**
* clutter_brightness_contrast_effect_new:
*
* Creates a new #ClutterBrightnessContrastEffect to be used with
* clutter_actor_add_effect()
*
* Return value: (transfer full): the newly created
* #ClutterBrightnessContrastEffect or %NULL. Use g_object_unref() when
* done.
*
* Since: 1.10
*/
ClutterEffect *
clutter_brightness_contrast_effect_new (void)
{
return g_object_new (CLUTTER_TYPE_BRIGHTNESS_CONTRAST_EFFECT, NULL);
}
/**
* clutter_brightness_contrast_effect_set_brightness_full:
* @effect: a #ClutterBrightnessContrastEffect
* @red: red component of the change in brightness
* @green: green component of the change in brightness
* @blue: blue component of the change in brightness
*
* The range for each component is [-1.0, 1.0] where 0.0 designates no change,
* values below 0.0 mean a decrease in brightness, and values above indicate
* an increase.
*
* Since: 1.10
*/
void
clutter_brightness_contrast_effect_set_brightness_full (ClutterBrightnessContrastEffect *effect,
gfloat red,
gfloat green,
gfloat blue)
{
g_return_if_fail (CLUTTER_IS_BRIGHTNESS_CONTRAST_EFFECT (effect));
if (red == effect->brightness_red &&
green == effect->brightness_green &&
blue == effect->brightness_blue)
return;
effect->brightness_red = red;
effect->brightness_green = green;
effect->brightness_blue = blue;
update_uniforms (effect);
clutter_effect_queue_repaint (CLUTTER_EFFECT (effect));
g_object_notify_by_pspec (G_OBJECT (effect), obj_props[PROP_BRIGHTNESS]);
}
/**
* clutter_brightness_contrast_effect_get_brightness:
* @effect: a #ClutterBrightnessContrastEffect
* @red: (out) (allow-none): return location for red component of the
* change in brightness
* @green: (out) (allow-none): return location for green component of the
* change in brightness
* @blue: (out) (allow-none): return location for blue component of the
* change in brightness
*
* Retrieves the change in brightness used by @effect.
*
* Since: 1.10
*/
void
clutter_brightness_contrast_effect_get_brightness (ClutterBrightnessContrastEffect *effect,
gfloat *red,
gfloat *green,
gfloat *blue)
{
g_return_if_fail (CLUTTER_IS_BRIGHTNESS_CONTRAST_EFFECT (effect));
if (red != NULL)
*red = effect->brightness_red;
if (green != NULL)
*green = effect->brightness_green;
if (blue != NULL)
*blue = effect->brightness_blue;
}
/**
* clutter_brightness_contrast_effect_set_brightness:
* @effect: a #ClutterBrightnessContrastEffect
* @brightness: the brightness change for all three components (r, g, b)
*
* The range of @brightness is [-1.0, 1.0], where 0.0 designates no change;
* a value below 0.0 indicates a decrease in brightness; and a value
* above 0.0 indicates an increase of brightness.
*
* Since: 1.10
*/
void
clutter_brightness_contrast_effect_set_brightness (ClutterBrightnessContrastEffect *effect,
gfloat brightness)
{
clutter_brightness_contrast_effect_set_brightness_full (effect,
brightness,
brightness,
brightness);
}
/**
* clutter_brightness_contrast_effect_set_contrast_full:
* @effect: a #ClutterBrightnessContrastEffect
* @red: red component of the change in contrast
* @green: green component of the change in contrast
* @blue: blue component of the change in contrast
*
* The range for each component is [-1.0, 1.0] where 0.0 designates no change,
* values below 0.0 mean a decrease in contrast, and values above indicate
* an increase.
*
* Since: 1.10
*/
void
clutter_brightness_contrast_effect_set_contrast_full (ClutterBrightnessContrastEffect *effect,
gfloat red,
gfloat green,
gfloat blue)
{
g_return_if_fail (CLUTTER_IS_BRIGHTNESS_CONTRAST_EFFECT (effect));
if (red == effect->contrast_red &&
green == effect->contrast_green &&
blue == effect->contrast_blue)
return;
effect->contrast_red = red;
effect->contrast_green = green;
effect->contrast_blue = blue;
update_uniforms (effect);
clutter_effect_queue_repaint (CLUTTER_EFFECT (effect));
g_object_notify_by_pspec (G_OBJECT (effect), obj_props[PROP_CONTRAST]);
}
/**
* clutter_brightness_contrast_effect_get_contrast:
* @effect: a #ClutterBrightnessContrastEffect
* @red: (out) (allow-none): return location for red component of the
* change in contrast
* @green: (out) (allow-none): return location for green component of the
* change in contrast
* @blue: (out) (allow-none): return location for blue component of the
* change in contrast
*
* Retrieves the contrast value used by @effect.
*
* Since: 1.10
*/
void
clutter_brightness_contrast_effect_get_contrast (ClutterBrightnessContrastEffect *effect,
gfloat *red,
gfloat *green,
gfloat *blue)
{
g_return_if_fail (CLUTTER_IS_BRIGHTNESS_CONTRAST_EFFECT (effect));
if (red != NULL)
*red = effect->contrast_red;
if (green != NULL)
*green = effect->contrast_green;
if (blue != NULL)
*blue = effect->contrast_blue;
}
/**
* clutter_brightness_contrast_effect_set_contrast:
* @effect: a #ClutterBrightnessContrastEffect
* @contrast: contrast change for all three channels
*
* The range for @contrast is [-1.0, 1.0], where 0.0 designates no change;
* a value below 0.0 indicates a decrease in contrast; and a value above
* 0.0 indicates an increase.
*
* Since: 1.10
*/
void
clutter_brightness_contrast_effect_set_contrast (ClutterBrightnessContrastEffect *effect,
gfloat contrast)
{
clutter_brightness_contrast_effect_set_contrast_full (effect,
contrast,
contrast,
contrast);
}