gimp/modules/cdisplay_gamma.c

377 lines
9.9 KiB
C

/* The GIMP -- an image manipulation program
* Copyright (C) 1999 Manish Singh <yosh@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 2 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, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "config.h"
#include <string.h>
#include <gtk/gtk.h>
#include "libgimpbase/gimpbase.h"
#include "libgimpmath/gimpmath.h"
#include "libgimpmodule/gimpmodule.h"
#include "libgimpwidgets/gimpwidgets.h"
#include "libgimp/libgimp-intl.h"
#define DEFAULT_GAMMA 1.0
#define CDISPLAY_TYPE_GAMMA (cdisplay_gamma_type)
#define CDISPLAY_GAMMA(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), CDISPLAY_TYPE_GAMMA, CdisplayGamma))
#define CDISPLAY_GAMMA_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), CDISPLAY_TYPE_GAMMA, CdisplayGammaClass))
#define CDISPLAY_IS_GAMMA(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CDISPLAY_TYPE_GAMMA))
#define CDISPLAY_IS_GAMMA_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), CDISPLAY_TYPE_GAMMA))
typedef struct _CdisplayGamma CdisplayGamma;
typedef struct _CdisplayGammaClass CdisplayGammaClass;
struct _CdisplayGamma
{
GimpColorDisplay parent_instance;
gdouble gamma;
guchar *lookup;
GtkWidget *hbox;
GtkObject *adjustment;
};
struct _CdisplayGammaClass
{
GimpColorDisplayClass parent_instance;
};
static GType cdisplay_gamma_get_type (GTypeModule *module);
static void cdisplay_gamma_class_init (CdisplayGammaClass *klass);
static void cdisplay_gamma_init (CdisplayGamma *gamma);
static void cdisplay_gamma_finalize (GObject *object);
static GimpColorDisplay * cdisplay_gamma_clone (GimpColorDisplay *display);
static void cdisplay_gamma_convert (GimpColorDisplay *display,
guchar *buf,
gint w,
gint h,
gint bpp,
gint bpl);
static void cdisplay_gamma_load_state (GimpColorDisplay *display,
GimpParasite *state);
static GimpParasite * cdisplay_gamma_save_state (GimpColorDisplay *display);
static GtkWidget * cdisplay_gamma_configure (GimpColorDisplay *display);
static void cdisplay_gamma_configure_reset (GimpColorDisplay *display);
static void gamma_create_lookup_table (CdisplayGamma *gamma);
static void gamma_configure_adj_callback (GtkAdjustment *adj,
CdisplayGamma *gamma);
static const GimpModuleInfo cdisplay_gamma_info =
{
GIMP_MODULE_ABI_VERSION,
N_("Gamma color display filter"),
"Manish Singh <yosh@gimp.org>",
"v0.2",
"(c) 1999, released under the GPL",
"October 14, 2000"
};
static GType cdisplay_gamma_type = 0;
static GimpColorDisplayClass *parent_class = NULL;
G_MODULE_EXPORT const GimpModuleInfo *
gimp_module_query (GTypeModule *module)
{
return &cdisplay_gamma_info;
}
G_MODULE_EXPORT gboolean
gimp_module_register (GTypeModule *module)
{
cdisplay_gamma_get_type (module);
return TRUE;
}
static GType
cdisplay_gamma_get_type (GTypeModule *module)
{
if (! cdisplay_gamma_type)
{
static const GTypeInfo display_info =
{
sizeof (CdisplayGammaClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) cdisplay_gamma_class_init,
NULL, /* class_finalize */
NULL, /* class_data */
sizeof (CdisplayGamma),
0, /* n_preallocs */
(GInstanceInitFunc) cdisplay_gamma_init,
};
cdisplay_gamma_type =
g_type_module_register_type (module,
GIMP_TYPE_COLOR_DISPLAY,
"CdisplayGamma",
&display_info, 0);
}
return cdisplay_gamma_type;
}
static void
cdisplay_gamma_class_init (CdisplayGammaClass *klass)
{
GObjectClass *object_class;
GimpColorDisplayClass *display_class;
object_class = G_OBJECT_CLASS (klass);
display_class = GIMP_COLOR_DISPLAY_CLASS (klass);
parent_class = g_type_class_peek_parent (klass);
object_class->finalize = cdisplay_gamma_finalize;
display_class->name = _("Gamma");
display_class->help_page = "modules/gamma.html";
display_class->clone = cdisplay_gamma_clone;
display_class->convert = cdisplay_gamma_convert;
display_class->load_state = cdisplay_gamma_load_state;
display_class->save_state = cdisplay_gamma_save_state;
display_class->configure = cdisplay_gamma_configure;
display_class->configure_reset = cdisplay_gamma_configure_reset;
}
static void
cdisplay_gamma_init (CdisplayGamma *gamma)
{
gint i;
gamma->gamma = DEFAULT_GAMMA;
gamma->lookup = g_new (guchar, 256);
for (i = 0; i < 256; i++)
gamma->lookup[i] = i;
}
static void
cdisplay_gamma_finalize (GObject *object)
{
CdisplayGamma *gamma;
gamma = CDISPLAY_GAMMA (object);
if (gamma->hbox)
gtk_widget_destroy (gamma->hbox);
if (gamma->lookup)
{
g_free (gamma->lookup);
gamma->lookup = NULL;
}
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static GimpColorDisplay *
cdisplay_gamma_clone (GimpColorDisplay *display)
{
CdisplayGamma *gamma;
CdisplayGamma *copy;
gamma = CDISPLAY_GAMMA (display);
copy = CDISPLAY_GAMMA (gimp_color_display_new (G_TYPE_FROM_INSTANCE (gamma)));
copy->gamma = gamma->gamma;
memcpy (copy->lookup, gamma->lookup, sizeof (guchar) * 256);
return GIMP_COLOR_DISPLAY (copy);
}
static void
cdisplay_gamma_convert (GimpColorDisplay *display,
guchar *buf,
gint width,
gint height,
gint bpp,
gint bpl)
{
CdisplayGamma *gamma;
gint i, j = height;
gamma = CDISPLAY_GAMMA (display);
/* You will not be using the entire buffer most of the time.
* Hence, the simplistic code for this is as follows:
*
* for (j = 0; j < height; j++)
* {
* for (i = 0; i < width * bpp; i++)
* buf[i] = lookup[buf[i]];
* buf += bpl;
* }
*/
width *= bpp;
bpl -= width;
while (j--)
{
i = width;
while (i--)
{
*buf = gamma->lookup[*buf];
buf++;
}
buf += bpl;
}
}
static void
cdisplay_gamma_load_state (GimpColorDisplay *display,
GimpParasite *state)
{
CdisplayGamma *gamma;
gamma = CDISPLAY_GAMMA (display);
#if G_BYTE_ORDER == G_BIG_ENDIAN
memcpy (&gamma->gamma, gimp_parasite_data (state), sizeof (gdouble));
#else
{
guint32 buf[2];
const guint32 *data;
data = gimp_parasite_data (state);
buf[0] = g_ntohl (data[1]);
buf[1] = g_ntohl (data[0]);
memcpy (&gamma->gamma, buf, sizeof (gdouble));
}
#endif
gamma_create_lookup_table (gamma);
}
static GimpParasite *
cdisplay_gamma_save_state (GimpColorDisplay *display)
{
CdisplayGamma *gamma;
guint32 buf[2];
gamma = CDISPLAY_GAMMA (display);
memcpy (buf, &gamma->gamma, sizeof (double));
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
{
guint32 tmp;
tmp = g_htonl (buf[0]);
buf[0] = g_htonl (buf[1]);
buf[1] = tmp;
}
#endif
return gimp_parasite_new ("Display/Gamma", GIMP_PARASITE_PERSISTENT,
sizeof (double), &buf);
}
static GtkWidget *
cdisplay_gamma_configure (GimpColorDisplay *display)
{
CdisplayGamma *gamma;
GtkWidget *label;
GtkWidget *spinbutton;
gamma = CDISPLAY_GAMMA (display);
if (gamma->hbox)
gtk_widget_destroy (gamma->hbox);
gamma->hbox = gtk_hbox_new (FALSE, 4);
g_object_add_weak_pointer (G_OBJECT (gamma->hbox), (gpointer) &gamma->hbox);
label = gtk_label_new ( _("Gamma:"));
gtk_box_pack_start (GTK_BOX (gamma->hbox), label, FALSE, FALSE, 0);
gtk_widget_show (label);
spinbutton = gimp_spin_button_new (&gamma->adjustment,
gamma->gamma, 0.01, 10.0, 0.01, 0.1, 0.0,
0.1, 3);
gtk_box_pack_start (GTK_BOX (gamma->hbox), spinbutton, FALSE, FALSE, 0);
gtk_widget_show (spinbutton);
g_signal_connect (gamma->adjustment, "value_changed",
G_CALLBACK (gamma_configure_adj_callback),
gamma);
return gamma->hbox;
}
static void
cdisplay_gamma_configure_reset (GimpColorDisplay *display)
{
CdisplayGamma *gamma;
gamma = CDISPLAY_GAMMA (display);
if (gamma->adjustment)
gtk_adjustment_set_value (GTK_ADJUSTMENT (gamma->adjustment), DEFAULT_GAMMA);
}
static void
gamma_create_lookup_table (CdisplayGamma *gamma)
{
gdouble one_over_gamma;
gdouble ind;
gint i;
if (gamma->gamma == 0.0)
gamma->gamma = 1.0;
one_over_gamma = 1.0 / gamma->gamma;
for (i = 0; i < 256; i++)
{
ind = (gdouble) i / 255.0;
gamma->lookup[i] = (guchar) (gint) (255 * pow (ind, one_over_gamma));
}
}
static void
gamma_configure_adj_callback (GtkAdjustment *adj,
CdisplayGamma *gamma)
{
gamma->gamma = adj->value;
gamma_create_lookup_table (gamma);
gimp_color_display_changed (GIMP_COLOR_DISPLAY (gamma));
}