gimp/app/operations/gimpoperationbrightnesscont...

141 lines
5.4 KiB
C

/* GIMP - The GNU Image Manipulation Program
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* gimpoperationbrightnesscontrast.c
* Copyright (C) 2012 Michael Natterer <mitch@gimp.org>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <cairo.h>
#include <gegl.h>
#include <gdk-pixbuf/gdk-pixbuf.h>
#include "libgimpcolor/gimpcolor.h"
#include "libgimpmath/gimpmath.h"
#include "operations-types.h"
#include "gimpbrightnesscontrastconfig.h"
#include "gimpoperationbrightnesscontrast.h"
#include "gimp-intl.h"
static gboolean gimp_operation_brightness_contrast_process (GeglOperation *operation,
void *in_buf,
void *out_buf,
glong samples,
const GeglRectangle *roi,
gint level);
G_DEFINE_TYPE (GimpOperationBrightnessContrast, gimp_operation_brightness_contrast,
GIMP_TYPE_OPERATION_POINT_FILTER)
#define parent_class gimp_operation_brightness_contrast_parent_class
static void
gimp_operation_brightness_contrast_class_init (GimpOperationBrightnessContrastClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (klass);
GeglOperationPointFilterClass *point_class = GEGL_OPERATION_POINT_FILTER_CLASS (klass);
object_class->set_property = gimp_operation_point_filter_set_property;
object_class->get_property = gimp_operation_point_filter_get_property;
gegl_operation_class_set_keys (operation_class,
"name", "gimp:brightness-contrast",
"categories", "color",
"description", _("Adjust brightness and contrast"),
NULL);
point_class->process = gimp_operation_brightness_contrast_process;
g_object_class_install_property (object_class,
GIMP_OPERATION_POINT_FILTER_PROP_CONFIG,
g_param_spec_object ("config",
"Config",
"The config object",
GIMP_TYPE_BRIGHTNESS_CONTRAST_CONFIG,
G_PARAM_READWRITE |
G_PARAM_CONSTRUCT));
}
static void
gimp_operation_brightness_contrast_init (GimpOperationBrightnessContrast *self)
{
}
static inline gfloat
gimp_operation_brightness_contrast_map (gfloat value,
gdouble brightness,
gdouble slant)
{
/* apply brightness */
if (brightness < 0.0)
value = value * (1.0 + brightness);
else
value = value + ((1.0 - value) * brightness);
value = (value - 0.5) * slant + 0.5;
return value;
}
static gboolean
gimp_operation_brightness_contrast_process (GeglOperation *operation,
void *in_buf,
void *out_buf,
glong samples,
const GeglRectangle *roi,
gint level)
{
GimpOperationPointFilter *point = GIMP_OPERATION_POINT_FILTER (operation);
GimpBrightnessContrastConfig *config = GIMP_BRIGHTNESS_CONTRAST_CONFIG (point->config);
gfloat *src = in_buf;
gfloat *dest = out_buf;
gdouble brightness;
gdouble slant;
if (! config)
return FALSE;
brightness = config->brightness / 2.0;
slant = tan ((config->contrast + 1) * G_PI_4);
while (samples--)
{
dest[RED] = gimp_operation_brightness_contrast_map (src[RED],
brightness,
slant);
dest[GREEN] = gimp_operation_brightness_contrast_map (src[GREEN],
brightness,
slant);
dest[BLUE] = gimp_operation_brightness_contrast_map (src[BLUE],
brightness,
slant);
dest[ALPHA] = src[ALPHA];
src += 4;
dest += 4;
}
return TRUE;
}