/* This file is an image processing operation for GEGL
*
* GEGL 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 3 of the License, or (at your option) any later version.
*
* GEGL 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 GEGL; if not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2008 Øyvind Kolås <pippin@gimp.org>
*/
#include "config.h"
#include <glib/gi18n-lib.h>
#ifdef GEGL_CHANT_PROPERTIES
gegl_chant_double (x1, _("x1"), -1000.0, 1000.0, 25.0, "")
gegl_chant_double (y1, _("y1"), -1000.0, 1000.0, 25.0, "")
gegl_chant_double (x2, _("x2"), -1000.0, 1000.0, 50.0, "")
gegl_chant_double (y2, _("y2"), -1000.0, 1000.0, 50.0, "")
gegl_chant_color (color1, _("Color"), "black",
_("One end of gradient"))
gegl_chant_color (color2, _("Other color"), "white",
_("One end of gradient"))
#else
#define GEGL_CHANT_TYPE_POINT_RENDER
#define GEGL_CHANT_C_FILE "radial-gradient.c"
#include "gegl-chant.h"
#include <math.h>
static void
prepare (GeglOperation *operation)
{
gegl_operation_set_format (operation, "output", babl_format ("RGBA float"));
}
static GeglRectangle
get_bounding_box (GeglOperation *operation)
{
GeglRectangle result = {-10000000, -10000000, 20000000, 20000000};
return result;
}
static gfloat dist(gfloat x1, gfloat y1, gfloat x2, gfloat y2)
{
return sqrt( (x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
}
static gboolean
process (GeglOperation *operation,
void *out_buf,
glong n_pixels,
const GeglRectangle *roi,
gint level)
{
GeglChantO *o = GEGL_CHANT_PROPERTIES (operation);
gfloat *out_pixel = out_buf;
gfloat color1[4];
gfloat color2[4];
gint x, y;
gfloat length = dist (o->x1, o->y1, o->x2, o->y2);
gegl_color_get_pixel (o->color1, babl_format ("RGBA float"), color1);
gegl_color_get_pixel (o->color2, babl_format ("RGBA float"), color2);
x= roi->x;
y= roi->y;
while (n_pixels--)
{
gfloat v;
gint c;
if (length == 0.0)
v = 0.5;
else
{
v = dist(x,y,o->x2,o->y2)/length;
if (v<0.0)
v= 0.0;
if (v>1.0)
v= 1.0;
}
for (c=0;c<4;c++)
out_pixel[c]=color1[c] * v + color2[c] * (1.0-v);
out_pixel += 4;
/* update x and y coordinates */
if (++x>=roi->x + roi->width)
{
x=roi->x;
y++;
}
}
return TRUE;
}
static void
gegl_chant_class_init (GeglChantClass *klass)
{
GeglOperationClass *operation_class;
GeglOperationPointRenderClass *point_render_class;
operation_class = GEGL_OPERATION_CLASS (klass);
point_render_class = GEGL_OPERATION_POINT_RENDER_CLASS (klass);
point_render_class->process = process;
operation_class->get_bounding_box = get_bounding_box;
operation_class->prepare = prepare;
operation_class->no_cache = TRUE;
gegl_operation_class_set_keys (operation_class,
"name" , "gegl:radial-gradient",
"categories" , "render",
"description" , _("Radial gradient renderer"),
NULL);
}
#endif