PIKApp/app/operations/pikaoperationsetalpha.c

193 lines
6.9 KiB
C

/* PIKA - Photo and Image Kooker Application
* a rebranding of The GNU Image Manipulation Program (created with heckimp)
* A derived work which may be trivial. However, any changes may be (C)2023 by Aldercone Studio
*
* Original copyright, applying to most contents (license remains unchanged):
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* pikaoperationsetalpha.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 <gegl.h>
#include "operations-types.h"
#include "pikaoperationsetalpha.h"
enum
{
PROP_0,
PROP_VALUE
};
static void pika_operation_set_alpha_get_property (GObject *object,
guint property_id,
GValue *value,
GParamSpec *pspec);
static void pika_operation_set_alpha_set_property (GObject *object,
guint property_id,
const GValue *value,
GParamSpec *pspec);
static void pika_operation_set_alpha_prepare (GeglOperation *operation);
static gboolean pika_operation_set_alpha_process (GeglOperation *operation,
void *in_buf,
void *aux_buf,
void *out_buf,
glong samples,
const GeglRectangle *roi,
gint level);
G_DEFINE_TYPE (PikaOperationSetAlpha, pika_operation_set_alpha,
GEGL_TYPE_OPERATION_POINT_COMPOSER)
#define parent_class pika_operation_set_alpha_parent_class
static void
pika_operation_set_alpha_class_init (PikaOperationSetAlphaClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (klass);
GeglOperationPointComposerClass *point_class = GEGL_OPERATION_POINT_COMPOSER_CLASS (klass);
object_class->set_property = pika_operation_set_alpha_set_property;
object_class->get_property = pika_operation_set_alpha_get_property;
gegl_operation_class_set_keys (operation_class,
"name", "pika:set-alpha",
"categories", "color",
"description", "Set a buffer's alpha channel to a value",
NULL);
operation_class->prepare = pika_operation_set_alpha_prepare;
point_class->process = pika_operation_set_alpha_process;
g_object_class_install_property (object_class, PROP_VALUE,
g_param_spec_double ("value",
"Value",
"The alpha value",
0.0, 1.0, 1.0,
G_PARAM_READWRITE |
G_PARAM_CONSTRUCT));
}
static void
pika_operation_set_alpha_init (PikaOperationSetAlpha *self)
{
}
static void
pika_operation_set_alpha_get_property (GObject *object,
guint property_id,
GValue *value,
GParamSpec *pspec)
{
PikaOperationSetAlpha *self = PIKA_OPERATION_SET_ALPHA (object);
switch (property_id)
{
case PROP_VALUE:
g_value_set_double (value, self->value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static void
pika_operation_set_alpha_set_property (GObject *object,
guint property_id,
const GValue *value,
GParamSpec *pspec)
{
PikaOperationSetAlpha *self = PIKA_OPERATION_SET_ALPHA (object);
switch (property_id)
{
case PROP_VALUE:
self->value = g_value_get_double (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static void
pika_operation_set_alpha_prepare (GeglOperation *operation)
{
const Babl *space = gegl_operation_get_source_space (operation, "input");
gegl_operation_set_format (operation, "input", babl_format_with_space ("RGBA float", space));
gegl_operation_set_format (operation, "aux", babl_format_with_space ("Y float", space));
gegl_operation_set_format (operation, "output", babl_format_with_space ("RGBA float", space));
}
static gboolean
pika_operation_set_alpha_process (GeglOperation *operation,
void *in_buf,
void *aux_buf,
void *out_buf,
glong samples,
const GeglRectangle *roi,
gint level)
{
PikaOperationSetAlpha *self = PIKA_OPERATION_SET_ALPHA (operation);
gfloat *src = in_buf;
gfloat *aux = aux_buf;
gfloat *dest = out_buf;
if (aux)
{
while (samples--)
{
dest[RED] = src[RED];
dest[GREEN] = src[GREEN];
dest[BLUE] = src[BLUE];
dest[ALPHA] = self->value * *aux;
src += 4;
aux += 1;
dest += 4;
}
}
else
{
while (samples--)
{
dest[RED] = src[RED];
dest[GREEN] = src[GREEN];
dest[BLUE] = src[BLUE];
dest[ALPHA] = self->value;
src += 4;
dest += 4;
}
}
return TRUE;
}