gimp/app/core/gimpimage-snap.c

746 lines
20 KiB
C

/* The GIMP -- an 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 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 <glib-object.h>
#include "core-types.h"
#include "gimp.h"
#include "gimpimage.h"
#include "gimpimage-grid.h"
#include "gimpimage-guides.h"
#include "gimpimage-snap.h"
#include "vectors/gimpstroke.h"
#include "vectors/gimpvectors.h"
#include "gimp-intl.h"
/* public functions */
gboolean
gimp_image_snap_x (GimpImage *image,
gdouble x,
gdouble *tx,
gdouble epsilon_x,
gboolean snap_to_guides,
gboolean snap_to_grid,
gboolean snap_to_canvas)
{
gdouble mindist = G_MAXDOUBLE;
gdouble dist;
gboolean snapped = FALSE;
g_return_val_if_fail (GIMP_IS_IMAGE (image), FALSE);
g_return_val_if_fail (tx != NULL, FALSE);
*tx = x;
if (! image->guides) snap_to_guides = FALSE;
if (! image->grid) snap_to_grid = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas))
return FALSE;
if (x < -epsilon_x || x >= (image->width + epsilon_x))
return FALSE;
if (snap_to_guides)
{
GList *list;
for (list = image->guides; list; list = g_list_next (list))
{
GimpGuide *guide = list->data;
if (guide->position < 0)
continue;
if (guide->orientation == GIMP_ORIENTATION_VERTICAL)
{
dist = ABS (guide->position - x);
if (dist < MIN (epsilon_x, mindist))
{
mindist = dist;
*tx = guide->position;
snapped = TRUE;
}
}
}
}
if (snap_to_grid)
{
GimpGrid *grid = gimp_image_get_grid (image);
gdouble xspacing;
gdouble xoffset;
gdouble i;
g_object_get (grid,
"xspacing", &xspacing,
"xoffset", &xoffset,
NULL);
for (i = xoffset; i <= image->width; i += xspacing)
{
if (i < 0)
continue;
dist = ABS (i - x);
if (dist < MIN (epsilon_x, mindist))
{
mindist = dist;
*tx = i;
snapped = TRUE;
}
}
}
if (snap_to_canvas)
{
dist = ABS (x);
if (dist < MIN (epsilon_x, mindist))
{
mindist = dist;
*tx = 0;
snapped = TRUE;
}
dist = ABS (image->width - x);
if (dist < MIN (epsilon_x, mindist))
{
mindist = dist;
*tx = image->width;
snapped = TRUE;
}
}
return snapped;
}
gboolean
gimp_image_snap_y (GimpImage *image,
gdouble y,
gdouble *ty,
gdouble epsilon_y,
gboolean snap_to_guides,
gboolean snap_to_grid,
gboolean snap_to_canvas)
{
gdouble mindist = G_MAXDOUBLE;
gdouble dist;
gboolean snapped = FALSE;
g_return_val_if_fail (GIMP_IS_IMAGE (image), FALSE);
g_return_val_if_fail (ty != NULL, FALSE);
*ty = y;
if (! image->guides) snap_to_guides = FALSE;
if (! image->grid) snap_to_grid = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas))
return FALSE;
if (y < -epsilon_y || y >= (image->height + epsilon_y))
return FALSE;
if (snap_to_guides)
{
GList *list;
for (list = image->guides; list; list = g_list_next (list))
{
GimpGuide *guide = list->data;
if (guide->position < 0)
continue;
if (guide->orientation == GIMP_ORIENTATION_HORIZONTAL)
{
dist = ABS (guide->position - y);
if (dist < MIN (epsilon_y, mindist))
{
mindist = dist;
*ty = guide->position;
snapped = TRUE;
}
}
}
}
if (snap_to_grid)
{
GimpGrid *grid = gimp_image_get_grid (image);
gdouble yspacing;
gdouble yoffset;
gdouble i;
g_object_get (grid,
"yspacing", &yspacing,
"yoffset", &yoffset,
NULL);
for (i = yoffset; i <= image->height; i += yspacing)
{
if (i < 0)
continue;
dist = ABS (i - y);
if (dist < MIN (epsilon_y, mindist))
{
mindist = dist;
*ty = i;
snapped = TRUE;
}
}
}
if (snap_to_canvas)
{
dist = ABS (y);
if (dist < MIN (epsilon_y, mindist))
{
mindist = dist;
*ty = 0;
snapped = TRUE;
}
dist = ABS (image->height - y);
if (dist < MIN (epsilon_y, mindist))
{
mindist = dist;
*ty = image->height;
snapped = TRUE;
}
}
return snapped;
}
gboolean
gimp_image_snap_point (GimpImage *image,
gdouble x,
gdouble y,
gdouble *tx,
gdouble *ty,
gdouble epsilon_x,
gdouble epsilon_y,
gboolean snap_to_guides,
gboolean snap_to_grid,
gboolean snap_to_canvas,
gboolean snap_to_vectors)
{
gdouble mindist_x = G_MAXDOUBLE;
gdouble mindist_y = G_MAXDOUBLE;
gdouble dist;
gboolean snapped = FALSE;
g_return_val_if_fail (GIMP_IS_IMAGE (image), FALSE);
g_return_val_if_fail (tx != NULL, FALSE);
g_return_val_if_fail (ty != NULL, FALSE);
*tx = x;
*ty = y;
if (! image->guides) snap_to_guides = FALSE;
if (! image->grid) snap_to_grid = FALSE;
if (! image->active_vectors) snap_to_vectors = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas || snap_to_vectors))
return FALSE;
if (x < -epsilon_x || x >= (image->width + epsilon_x) ||
y < -epsilon_y || y >= (image->height + epsilon_y))
{
return FALSE;
}
if (snap_to_guides)
{
GList *list;
for (list = image->guides; list; list = g_list_next (list))
{
GimpGuide *guide = list->data;
if (guide->position < 0)
continue;
switch (guide->orientation)
{
case GIMP_ORIENTATION_HORIZONTAL:
dist = ABS (guide->position - y);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty = guide->position;
snapped = TRUE;
}
break;
case GIMP_ORIENTATION_VERTICAL:
dist = ABS (guide->position - x);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx = guide->position;
snapped = TRUE;
}
break;
default:
break;
}
}
}
if (snap_to_grid)
{
GimpGrid *grid = gimp_image_get_grid (image);
gdouble xspacing, yspacing;
gdouble xoffset, yoffset;
gdouble i;
g_object_get (grid,
"xspacing", &xspacing,
"yspacing", &yspacing,
"xoffset", &xoffset,
"yoffset", &yoffset,
NULL);
for (i = xoffset; i <= image->width; i += xspacing)
{
if (i < 0)
continue;
dist = ABS (i - x);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx = i;
snapped = TRUE;
}
}
for (i = yoffset; i <= image->height; i += yspacing)
{
if (i < 0)
continue;
dist = ABS (i - y);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty = i;
snapped = TRUE;
}
}
}
if (snap_to_canvas)
{
dist = ABS (x);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx = 0;
snapped = TRUE;
}
dist = ABS (image->width - x);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx = image->width;
snapped = TRUE;
}
dist = ABS (y);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty = 0;
snapped = TRUE;
}
dist = ABS (image->height - y);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty = image->height;
snapped = TRUE;
}
}
if (snap_to_vectors)
{
GimpVectors *vectors = gimp_image_get_active_vectors (image);
GimpStroke *stroke = NULL;
GimpCoords coords = { 0, 0, 0, 0, 0 };
coords.x = x;
coords.y = y;
while ((stroke = gimp_vectors_stroke_get_next (vectors, stroke)))
{
GimpCoords nearest;
if (gimp_stroke_nearest_point_get (stroke, &coords, 1.0,
&nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.x - x);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx = nearest.x;
snapped = TRUE;
}
dist = ABS (nearest.y - y);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty = nearest.y;
snapped = TRUE;
}
}
}
}
return snapped;
}
gboolean
gimp_image_snap_rectangle (GimpImage *image,
gdouble x1,
gdouble y1,
gdouble x2,
gdouble y2,
gdouble *tx1,
gdouble *ty1,
gdouble epsilon_x,
gdouble epsilon_y,
gboolean snap_to_guides,
gboolean snap_to_grid,
gboolean snap_to_canvas,
gboolean snap_to_vectors)
{
gdouble nx, ny;
gdouble mindist_x = G_MAXDOUBLE;
gdouble mindist_y = G_MAXDOUBLE;
gboolean snapped = FALSE;
g_return_val_if_fail (GIMP_IS_IMAGE (image), FALSE);
g_return_val_if_fail (tx1 != NULL, FALSE);
g_return_val_if_fail (ty1 != NULL, FALSE);
*tx1 = x1;
*ty1 = y1;
if (! image->guides) snap_to_guides = FALSE;
if (! image->grid) snap_to_grid = FALSE;
if (! image->active_vectors) snap_to_vectors = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas || snap_to_vectors))
return FALSE;
/* left edge */
if (gimp_image_snap_x (image, x1, &nx,
MIN (epsilon_x, mindist_x),
snap_to_guides,
snap_to_grid,
snap_to_canvas))
{
mindist_x = ABS (nx - x1);
*tx1 = nx;
snapped = TRUE;
}
/* right edge */
if (gimp_image_snap_x (image, x2, &nx,
MIN (epsilon_x, mindist_x),
snap_to_guides,
snap_to_grid,
snap_to_canvas))
{
mindist_x = ABS (nx - x2);
*tx1 = RINT (x1 + (nx - x2));
snapped = TRUE;
}
/* top edge */
if (gimp_image_snap_y (image, y1, &ny,
MIN (epsilon_y, mindist_y),
snap_to_guides,
snap_to_grid,
snap_to_canvas))
{
mindist_y = ABS (ny - y1);
*ty1 = ny;
snapped = TRUE;
}
/* bottom edge */
if (gimp_image_snap_y (image, y2, &ny,
MIN (epsilon_y, mindist_y),
snap_to_guides,
snap_to_grid,
snap_to_canvas))
{
mindist_y = ABS (ny - y2);
*ty1 = RINT (y1 + (ny - y2));
snapped = TRUE;
}
if (snap_to_vectors)
{
GimpVectors *vectors = gimp_image_get_active_vectors (image);
GimpStroke *stroke = NULL;
GimpCoords coords1 = GIMP_COORDS_DEFAULT_VALUES;
GimpCoords coords2 = GIMP_COORDS_DEFAULT_VALUES;
while ((stroke = gimp_vectors_stroke_get_next (vectors, stroke)))
{
GimpCoords nearest;
gdouble dist;
/* top edge */
coords1.x = x1;
coords1.y = y1;
coords2.x = x2;
coords2.y = y1;
if (gimp_stroke_nearest_tangent_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.y - y1);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty1 = nearest.y;
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.x - x1);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx1 = nearest.x;
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords2, &coords1,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.x - x2);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx1 = RINT (x1 + (nearest.x - x2));
snapped = TRUE;
}
}
/* bottom edge */
coords1.x = x1;
coords1.y = y2;
coords2.x = x2;
coords2.y = y2;
if (gimp_stroke_nearest_tangent_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.y - y2);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty1 = RINT (y1 + (nearest.y - y2));
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.x - x1);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx1 = nearest.x;
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords2, &coords1,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.x - x2);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx1 = RINT (x1 + (nearest.x - x2));
snapped = TRUE;
}
}
/* left edge */
coords1.x = x1;
coords1.y = y1;
coords2.x = x1;
coords2.y = y2;
if (gimp_stroke_nearest_tangent_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.x - x1);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx1 = nearest.x;
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.y - y1);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty1 = nearest.y;
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords2, &coords1,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.y - y2);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty1 = RINT (y1 + (nearest.y - y2));
snapped = TRUE;
}
}
/* right edge */
coords1.x = x2;
coords1.y = y1;
coords2.x = x2;
coords2.y = y2;
if (gimp_stroke_nearest_tangent_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.x - x2);
if (dist < MIN (epsilon_x, mindist_x))
{
mindist_x = dist;
*tx1 = RINT (x1 + (nearest.x - x2));
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.y - y1);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty1 = nearest.y;
snapped = TRUE;
}
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords2, &coords1,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
dist = ABS (nearest.y - y2);
if (dist < MIN (epsilon_y, mindist_y))
{
mindist_y = dist;
*ty1 = RINT (y1 + (nearest.y - y2));
snapped = TRUE;
}
}
}
}
return snapped;
}