gimp/app/paint/gimppaintcore-stroke.c

414 lines
12 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 <gegl.h>
#include "libgimpmath/gimpmath.h"
#include "paint-types.h"
#include "base/boundary.h"
#include "core/gimpdrawable.h"
#include "core/gimperror.h"
#include "vectors/gimpstroke.h"
#include "vectors/gimpvectors.h"
#include "gimppaintcore.h"
#include "gimppaintcore-stroke.h"
#include "gimppaintoptions.h"
#include "gimp-intl.h"
static void gimp_paint_core_stroke_emulate_dynamics (GimpCoords *coords,
gint length);
static const GimpCoords default_coords = GIMP_COORDS_DEFAULT_VALUES;
gboolean
gimp_paint_core_stroke (GimpPaintCore *core,
GimpDrawable *drawable,
GimpPaintOptions *paint_options,
GimpCoords *strokes,
gint n_strokes,
gboolean push_undo,
GError **error)
{
g_return_val_if_fail (GIMP_IS_PAINT_CORE (core), FALSE);
g_return_val_if_fail (GIMP_IS_DRAWABLE (drawable), FALSE);
g_return_val_if_fail (gimp_item_is_attached (GIMP_ITEM (drawable)), FALSE);
g_return_val_if_fail (GIMP_IS_PAINT_OPTIONS (paint_options), FALSE);
g_return_val_if_fail (strokes != NULL, FALSE);
g_return_val_if_fail (n_strokes > 0, FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
if (gimp_paint_core_start (core, drawable, paint_options, &strokes[0],
error))
{
gint i;
core->start_coords = strokes[0];
core->last_coords = strokes[0];
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_INIT, 0);
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_MOTION, 0);
for (i = 1; i < n_strokes; i++)
{
gimp_paint_core_interpolate (core, drawable, paint_options,
&strokes[i], 0);
}
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_FINISH, 0);
gimp_paint_core_finish (core, drawable, push_undo);
gimp_paint_core_cleanup (core);
return TRUE;
}
return FALSE;
}
gboolean
gimp_paint_core_stroke_boundary (GimpPaintCore *core,
GimpDrawable *drawable,
GimpPaintOptions *paint_options,
gboolean emulate_dynamics,
const BoundSeg *bound_segs,
gint n_bound_segs,
gint offset_x,
gint offset_y,
gboolean push_undo,
GError **error)
{
GimpImage *image;
BoundSeg *stroke_segs;
gint n_stroke_segs;
gint off_x;
gint off_y;
GimpCoords *coords;
gboolean initialized = FALSE;
gint n_coords;
gint seg;
gint s;
g_return_val_if_fail (GIMP_IS_PAINT_CORE (core), FALSE);
g_return_val_if_fail (GIMP_IS_DRAWABLE (drawable), FALSE);
g_return_val_if_fail (gimp_item_is_attached (GIMP_ITEM (drawable)), FALSE);
g_return_val_if_fail (GIMP_IS_PAINT_OPTIONS (paint_options), FALSE);
g_return_val_if_fail (bound_segs != NULL && n_bound_segs > 0, FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
image = gimp_item_get_image (GIMP_ITEM (drawable));
stroke_segs = boundary_sort (bound_segs, n_bound_segs, &n_stroke_segs);
if (n_stroke_segs == 0)
return TRUE;
gimp_item_get_offset (GIMP_ITEM (drawable), &off_x, &off_y);
off_x -= offset_x;
off_y -= offset_y;
coords = g_new0 (GimpCoords, n_bound_segs + 4);
seg = 0;
n_coords = 0;
/* we offset all coordinates by 0.5 to align the brush with the path */
coords[n_coords] = default_coords;
coords[n_coords].x = (gdouble) (stroke_segs[0].x1 - off_x + 0.5);
coords[n_coords].y = (gdouble) (stroke_segs[0].y1 - off_y + 0.5);
n_coords++;
for (s = 0; s < n_stroke_segs; s++)
{
while (stroke_segs[seg].x1 != -1 ||
stroke_segs[seg].x2 != -1 ||
stroke_segs[seg].y1 != -1 ||
stroke_segs[seg].y2 != -1)
{
coords[n_coords] = default_coords;
coords[n_coords].x = (gdouble) (stroke_segs[seg].x1 - off_x + 0.5);
coords[n_coords].y = (gdouble) (stroke_segs[seg].y1 - off_y + 0.5);
n_coords++;
seg++;
}
/* Close the stroke points up */
coords[n_coords] = coords[0];
n_coords++;
if (emulate_dynamics)
gimp_paint_core_stroke_emulate_dynamics (coords, n_coords);
if (initialized ||
gimp_paint_core_start (core, drawable, paint_options, &coords[0],
error))
{
gint i;
initialized = TRUE;
core->cur_coords = coords[0];
core->start_coords = coords[0];
core->last_coords = coords[0];
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_INIT, 0);
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_MOTION, 0);
for (i = 1; i < n_coords; i++)
{
gimp_paint_core_interpolate (core, drawable, paint_options,
&coords[i], 0);
}
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_FINISH, 0);
}
else
{
break;
}
n_coords = 0;
seg++;
coords[n_coords] = default_coords;
coords[n_coords].x = (gdouble) (stroke_segs[seg].x1 - off_x + 0.5);
coords[n_coords].y = (gdouble) (stroke_segs[seg].y1 - off_y + 0.5);
n_coords++;
}
if (initialized)
{
gimp_paint_core_finish (core, drawable, push_undo);
gimp_paint_core_cleanup (core);
}
g_free (coords);
g_free (stroke_segs);
return initialized;
}
gboolean
gimp_paint_core_stroke_vectors (GimpPaintCore *core,
GimpDrawable *drawable,
GimpPaintOptions *paint_options,
gboolean emulate_dynamics,
GimpVectors *vectors,
gboolean push_undo,
GError **error)
{
GList *stroke;
gboolean initialized = FALSE;
gboolean due_to_lack_of_points = FALSE;
gint off_x, off_y;
gint vectors_off_x, vectors_off_y;
g_return_val_if_fail (GIMP_IS_PAINT_CORE (core), FALSE);
g_return_val_if_fail (GIMP_IS_DRAWABLE (drawable), FALSE);
g_return_val_if_fail (gimp_item_is_attached (GIMP_ITEM (drawable)), FALSE);
g_return_val_if_fail (GIMP_IS_PAINT_OPTIONS (paint_options), FALSE);
g_return_val_if_fail (GIMP_IS_VECTORS (vectors), FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
gimp_item_get_offset (GIMP_ITEM (vectors), &vectors_off_x, &vectors_off_y);
gimp_item_get_offset (GIMP_ITEM (drawable), &off_x, &off_y);
off_x -= vectors_off_x;
off_y -= vectors_off_y;
for (stroke = vectors->strokes; stroke; stroke = stroke->next)
{
GArray *coords;
gboolean closed;
coords = gimp_stroke_interpolate (GIMP_STROKE (stroke->data),
1.0, &closed);
if (coords && coords->len)
{
gint i;
for (i = 0; i < coords->len; i++)
{
g_array_index (coords, GimpCoords, i).x -= off_x;
g_array_index (coords, GimpCoords, i).y -= off_y;
}
if (emulate_dynamics)
gimp_paint_core_stroke_emulate_dynamics ((GimpCoords *) coords->data,
coords->len);
if (initialized ||
gimp_paint_core_start (core, drawable, paint_options,
&g_array_index (coords, GimpCoords, 0),
error))
{
initialized = TRUE;
core->cur_coords = g_array_index (coords, GimpCoords, 0);
core->start_coords = g_array_index (coords, GimpCoords, 0);
core->last_coords = g_array_index (coords, GimpCoords, 0);
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_INIT, 0);
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_MOTION, 0);
for (i = 1; i < coords->len; i++)
{
gimp_paint_core_interpolate (core, drawable, paint_options,
&g_array_index (coords, GimpCoords, i),
0);
}
gimp_paint_core_paint (core, drawable, paint_options,
GIMP_PAINT_STATE_FINISH, 0);
}
else
{
if (coords)
g_array_free (coords, TRUE);
break;
}
}
else
{
due_to_lack_of_points = TRUE;
}
if (coords)
g_array_free (coords, TRUE);
}
if (initialized)
{
gimp_paint_core_finish (core, drawable, push_undo);
gimp_paint_core_cleanup (core);
}
if (! initialized && due_to_lack_of_points && *error == NULL)
{
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("Not enough points to stroke"));
}
return initialized;
}
static void
gimp_paint_core_stroke_emulate_dynamics (GimpCoords *coords,
gint length)
{
const gint ramp_length = length / 3;
/* Calculate and create pressure ramp parameters */
if (ramp_length > 0)
{
gdouble slope = 1.0 / (gdouble) (ramp_length);
gint i;
/* Calculate pressure start ramp */
for (i = 0; i < ramp_length; i++)
{
coords[i].pressure = i * slope;
}
/* Calculate pressure end ramp */
for (i = length - ramp_length; i < length; i++)
{
coords[i].pressure = 1.0 - (i - (length - ramp_length)) * slope;
}
}
/* Calculate and create velocity ramp parameters */
if (length > 0)
{
gdouble slope = 1.0 / length;
gint i;
/* Calculate velocity end ramp */
for (i = 0; i < length; i++)
{
coords[i].velocity = i * slope;
}
}
if (length > 0)
{
gint i;
/* Fill in direction */
for (i = 2; i < length; i++)
{
gdouble delta_x = coords[i - 1].x - coords[i].x;
gdouble delta_y = coords[i - 1].y - coords[i].y;
if (delta_x == 0)
{
coords[i].direction = coords[i - 1].direction;
}
else
{
coords[i].direction = atan (delta_y / delta_x) / (2 * G_PI);
if (delta_x > 0.0)
coords[i].direction = coords[i].direction + 0.5;
}
/* This should avoid confusing the interpolator on sharp
* turns where the angle warps
*/
if (fabs (coords[i].direction - coords[i - 1].direction) > 0.5)
coords[i].direction = coords[i].direction + 1.0;
}
if (length > 2)
{
coords[0].direction = coords[2].direction;
coords[1].direction = coords[2].direction;
}
}
}