gimp/app/base/colorize.c

134 lines
3.4 KiB
C

/* GIMP - The GNU Image Manipulation Program
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* 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 <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <glib-object.h>
#include "libgimpcolor/gimpcolor.h"
#include "libgimpmath/gimpmath.h"
#include "base-types.h"
#include "colorize.h"
#include "pixel-region.h"
void
colorize_init (Colorize *colorize)
{
gint i;
g_return_if_fail (colorize != NULL);
colorize->hue = 180.0;
colorize->saturation = 50.0;
colorize->lightness = 0.0;
for (i = 0; i < 256; i ++)
{
colorize->lum_red_lookup[i] = i * GIMP_RGB_LUMINANCE_RED;
colorize->lum_green_lookup[i] = i * GIMP_RGB_LUMINANCE_GREEN;
colorize->lum_blue_lookup[i] = i * GIMP_RGB_LUMINANCE_BLUE;
}
}
void
colorize_calculate (Colorize *colorize)
{
GimpHSL hsl;
GimpRGB rgb;
gint i;
g_return_if_fail (colorize != NULL);
hsl.h = colorize->hue / 360.0;
hsl.s = colorize->saturation / 100.0;
/* Calculate transfers */
for (i = 0; i < 256; i ++)
{
hsl.l = (gdouble) i / 255.0;
gimp_hsl_to_rgb (&hsl, &rgb);
/* this used to read i * rgb.r,g,b in GIMP 2.4, but this produced
* darkened results, multiplying with 255 is correct and preserves
* the lightness unless modified with the slider.
*/
colorize->final_red_lookup[i] = 255.0 * rgb.r;
colorize->final_green_lookup[i] = 255.0 * rgb.g;
colorize->final_blue_lookup[i] = 255.0 * rgb.b;
}
}
void
colorize (Colorize *colorize,
PixelRegion *srcPR,
PixelRegion *destPR)
{
const guchar *src, *s;
guchar *dest, *d;
gboolean alpha;
gint w, h;
gint lum;
/* Set the transfer arrays (for speed) */
h = srcPR->h;
src = srcPR->data;
dest = destPR->data;
alpha = (srcPR->bytes == 4) ? TRUE : FALSE;
while (h--)
{
w = srcPR->w;
s = src;
d = dest;
while (w--)
{
lum = (colorize->lum_red_lookup[s[RED]] +
colorize->lum_green_lookup[s[GREEN]] +
colorize->lum_blue_lookup[s[BLUE]]); /* luminosity */
if (colorize->lightness > 0)
{
lum = (gdouble) lum * (100.0 - colorize->lightness) / 100.0;
lum += 255 - (100.0 - colorize->lightness) * 255.0 / 100.0;
}
else if (colorize->lightness < 0)
{
lum = (gdouble) lum * (colorize->lightness + 100.0) / 100.0;
}
d[RED] = colorize->final_red_lookup[lum];
d[GREEN] = colorize->final_green_lookup[lum];
d[BLUE] = colorize->final_blue_lookup[lum];
if (alpha)
d[ALPHA] = s[ALPHA];
s += srcPR->bytes;
d += destPR->bytes;
}
src += srcPR->rowstride;
dest += destPR->rowstride;
}
}