/* 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 2011 Audrey Mandet <mandet.audrey@gmail.com>
* Copyright (c) 1997 Eric L. Hernes (erich@rrnet.com)
*/
#include "config.h"
#include <glib/gi18n-lib.h>
#include <math.h>
#ifdef GEGL_CHANT_PROPERTIES
gegl_chant_double_ui (x, _("X"), -G_MAXDOUBLE, G_MAXDOUBLE, 0.0, 0.0, 1024.0, 1.0,
_("X coordinate of the center of the waves"))
gegl_chant_double_ui (y, _("Y"), -G_MAXDOUBLE, G_MAXDOUBLE, 0.0, 0.0, 1024.0, 1.0,
_("Coordinate y of the center of the waves"))
gegl_chant_double (amplitude, _("Amplitude"), 0.0, 1000.0, 25.0,
_("Amplitude of the ripple"))
gegl_chant_double (period, _("Period"), 0.0, 1000.0, 200.0,
_("Period of the ripple"))
gegl_chant_double (phi, _("Phase shift"), -1.0, 1.0, 0.0,
_("Phase shift"))
gegl_chant_enum (sampler_type, _("Sampler"), GeglSamplerType, GEGL_TYPE_SAMPLER_TYPE,
GEGL_SAMPLER_CUBIC, _("Sampler used internally"))
#else
#define GEGL_CHANT_TYPE_AREA_FILTER
#define GEGL_CHANT_C_FILE "waves.c"
#include "gegl-chant.h"
#include <stdio.h>
#include <math.h>
static void prepare (GeglOperation *operation)
{
GeglChantO *o;
GeglOperationAreaFilter *op_area;
op_area = GEGL_OPERATION_AREA_FILTER (operation);
o = GEGL_CHANT_PROPERTIES (operation);
op_area->left = o->amplitude;
op_area->right = o->amplitude;
op_area->top = o->amplitude;
op_area->bottom = o->amplitude;
gegl_operation_set_format (operation, "input",
babl_format ("RGBA float"));
gegl_operation_set_format (operation, "output",
babl_format ("RGBA float"));
}
static gboolean
process (GeglOperation *operation,
GeglBuffer *input,
GeglBuffer *output,
const GeglRectangle *result,
gint level)
{
GeglChantO *o = GEGL_CHANT_PROPERTIES (operation);
gint x = result->x; /* initial x */
gint y = result->y; /* and y coordinates */
gfloat *dst_buf = g_slice_alloc (result->width * result->height * 4 * sizeof(gfloat));
gfloat *out_pixel = dst_buf;
GeglSampler *sampler = gegl_buffer_sampler_new (input,
babl_format ("RGBA float"),
o->sampler_type);
gint n_pixels = result->width * result->height;
while (n_pixels--)
{
gdouble coordsx = 0.0;
gdouble coordsy = 0.0;
gdouble radius = 0.0;
gdouble shift = 0.0;
gdouble ux = 0.0; /* unit vector of the radius */
gdouble uy = 0.0;
gdouble vx = 0.0; /* orthogonal vector of u */
gdouble vy = 0.0;
gdouble dx = 0.0;
gdouble dy = 0.0;
dx = (gdouble)x-o->x;
dy = (gdouble)y-o->y;
radius = sqrt( dx * dx + dy * dy );
shift = o->amplitude * sin(2.0 * G_PI * radius / o->period + 2.0 * G_PI * o->phi);
ux = dx / radius;
uy = dy / radius;
vx = -uy;
vy = ux;
coordsx = x + shift * vx;
coordsy = y + shift * vy;
gegl_sampler_get (sampler,
coordsx,
coordsy,
NULL,
out_pixel);
out_pixel += 4;
/* update x and y coordinates */
x++;
if (x>=result->x + result->width)
{
x=result->x;
y++;
}
}
gegl_buffer_set (output, result, 0, babl_format ("RGBA float"), dst_buf, GEGL_AUTO_ROWSTRIDE);
g_slice_free1 (result->width * result->height * 4 * sizeof(gfloat), dst_buf);
g_object_unref (sampler);
return TRUE;
}
static void
gegl_chant_class_init (GeglChantClass *klass)
{
GeglOperationClass *operation_class;
GeglOperationFilterClass *filter_class;
operation_class = GEGL_OPERATION_CLASS (klass);
filter_class = GEGL_OPERATION_FILTER_CLASS (klass);
filter_class->process = process;
operation_class->prepare = prepare;
gegl_operation_class_set_keys (operation_class,
"name" , "gegl:waves",
"categories" , "distort",
"description", _("Transform the buffer with waves"),
NULL);
}
#endif