/* 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 .
*/
#include "config.h"
#include
#include
#include "libgimpmath/gimpmath.h"
#include "core-types.h"
#include "gimp.h"
#include "gimpgrid.h"
#include "gimpguide.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"
static gboolean gimp_image_snap_distance (const gdouble unsnapped,
const gdouble nearest,
const gdouble epsilon,
gdouble *mindist,
gdouble *target);
/* 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;
gboolean snapped = FALSE;
g_return_val_if_fail (GIMP_IS_IMAGE (image), FALSE);
g_return_val_if_fail (tx != NULL, FALSE);
*tx = x;
if (! gimp_image_get_guides (image)) snap_to_guides = FALSE;
if (! gimp_image_get_grid (image)) snap_to_grid = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas))
return FALSE;
if (x < -epsilon_x || x >= (gimp_image_get_width (image) + epsilon_x))
return FALSE;
if (snap_to_guides)
{
GList *list;
for (list = gimp_image_get_guides (image); list; list = g_list_next (list))
{
GimpGuide *guide = list->data;
gint position = gimp_guide_get_position (guide);
if (gimp_guide_is_custom (guide))
continue;
if (gimp_guide_get_orientation (guide) == GIMP_ORIENTATION_VERTICAL)
{
snapped |= gimp_image_snap_distance (x, position,
epsilon_x,
&mindist, tx);
}
}
}
if (snap_to_grid)
{
GimpGrid *grid = gimp_image_get_grid (image);
gdouble xspacing;
gdouble xoffset;
gimp_grid_get_spacing (grid, &xspacing, NULL);
gimp_grid_get_offset (grid, &xoffset, NULL);
if (xspacing > 0.0)
{
gdouble nearest;
nearest = xoffset + RINT ((x - xoffset) / xspacing) * xspacing;
snapped |= gimp_image_snap_distance (x, nearest,
epsilon_x,
&mindist, tx);
}
}
if (snap_to_canvas)
{
snapped |= gimp_image_snap_distance (x, 0,
epsilon_x,
&mindist, tx);
snapped |= gimp_image_snap_distance (x, gimp_image_get_width (image),
epsilon_x,
&mindist, tx);
}
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;
gboolean snapped = FALSE;
g_return_val_if_fail (GIMP_IS_IMAGE (image), FALSE);
g_return_val_if_fail (ty != NULL, FALSE);
*ty = y;
if (! gimp_image_get_guides (image)) snap_to_guides = FALSE;
if (! gimp_image_get_grid (image)) snap_to_grid = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas))
return FALSE;
if (y < -epsilon_y || y >= (gimp_image_get_height (image) + epsilon_y))
return FALSE;
if (snap_to_guides)
{
GList *list;
for (list = gimp_image_get_guides (image); list; list = g_list_next (list))
{
GimpGuide *guide = list->data;
gint position = gimp_guide_get_position (guide);
if (gimp_guide_is_custom (guide))
continue;
if (gimp_guide_get_orientation (guide) == GIMP_ORIENTATION_HORIZONTAL)
{
snapped |= gimp_image_snap_distance (y, position,
epsilon_y,
&mindist, ty);
}
}
}
if (snap_to_grid)
{
GimpGrid *grid = gimp_image_get_grid (image);
gdouble yspacing;
gdouble yoffset;
gimp_grid_get_spacing (grid, NULL, &yspacing);
gimp_grid_get_offset (grid, NULL, &yoffset);
if (yspacing > 0.0)
{
gdouble nearest;
nearest = yoffset + RINT ((y - yoffset) / yspacing) * yspacing;
snapped |= gimp_image_snap_distance (y, nearest,
epsilon_y,
&mindist, ty);
}
}
if (snap_to_canvas)
{
snapped |= gimp_image_snap_distance (y, 0,
epsilon_y,
&mindist, ty);
snapped |= gimp_image_snap_distance (y, gimp_image_get_height (image),
epsilon_y,
&mindist, ty);
}
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,
gboolean show_all)
{
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 (tx != NULL, FALSE);
g_return_val_if_fail (ty != NULL, FALSE);
*tx = x;
*ty = y;
if (! gimp_image_get_guides (image)) snap_to_guides = FALSE;
if (! gimp_image_get_grid (image)) snap_to_grid = FALSE;
if (! gimp_image_get_active_vectors (image)) snap_to_vectors = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas || snap_to_vectors))
return FALSE;
if (! show_all &&
(x < -epsilon_x || x >= (gimp_image_get_width (image) + epsilon_x) ||
y < -epsilon_y || y >= (gimp_image_get_height (image) + epsilon_y)))
{
/* Off-canvas grid is invisible unless "show all" option is
* enabled. So let's not snap to the invisible grid.
*/
snap_to_grid = FALSE;
snap_to_canvas = FALSE;
}
if (snap_to_guides)
{
GList *list;
for (list = gimp_image_get_guides (image); list; list = g_list_next (list))
{
GimpGuide *guide = list->data;
gint position = gimp_guide_get_position (guide);
if (gimp_guide_is_custom (guide))
continue;
switch (gimp_guide_get_orientation (guide))
{
case GIMP_ORIENTATION_HORIZONTAL:
snapped |= gimp_image_snap_distance (y, position,
epsilon_y,
&mindist_y, ty);
break;
case GIMP_ORIENTATION_VERTICAL:
snapped |= gimp_image_snap_distance (x, position,
epsilon_x,
&mindist_x, tx);
break;
default:
break;
}
}
}
if (snap_to_grid)
{
GimpGrid *grid = gimp_image_get_grid (image);
gdouble xspacing, yspacing;
gdouble xoffset, yoffset;
gimp_grid_get_spacing (grid, &xspacing, &yspacing);
gimp_grid_get_offset (grid, &xoffset, &yoffset);
if (xspacing > 0.0)
{
gdouble nearest;
nearest = xoffset + RINT ((x - xoffset) / xspacing) * xspacing;
snapped |= gimp_image_snap_distance (x, nearest,
epsilon_x,
&mindist_x, tx);
}
if (yspacing > 0.0)
{
gdouble nearest;
nearest = yoffset + RINT ((y - yoffset) / yspacing) * yspacing;
snapped |= gimp_image_snap_distance (y, nearest,
epsilon_y,
&mindist_y, ty);
}
}
if (snap_to_canvas)
{
snapped |= gimp_image_snap_distance (x, 0,
epsilon_x,
&mindist_x, tx);
snapped |= gimp_image_snap_distance (x, gimp_image_get_width (image),
epsilon_x,
&mindist_x, tx);
snapped |= gimp_image_snap_distance (y, 0,
epsilon_y,
&mindist_y, ty);
snapped |= gimp_image_snap_distance (y, gimp_image_get_height (image),
epsilon_y,
&mindist_y, ty);
}
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)
{
snapped |= gimp_image_snap_distance (x, nearest.x,
epsilon_x,
&mindist_x, tx);
snapped |= gimp_image_snap_distance (y, nearest.y,
epsilon_y,
&mindist_y, ty);
}
}
}
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;
gdouble x_center = (x1 + x2) / 2.0;
gdouble y_center = (y1 + y2) / 2.0;
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 (! gimp_image_get_guides (image)) snap_to_guides = FALSE;
if (! gimp_image_get_grid (image)) snap_to_grid = FALSE;
if (! gimp_image_get_active_vectors (image)) 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;
}
/* center, vertical */
if (gimp_image_snap_x (image, x_center, &nx,
MIN (epsilon_x, mindist_x),
snap_to_guides,
snap_to_grid,
snap_to_canvas))
{
mindist_x = ABS (nx - x_center);
*tx1 = RINT (x1 + (nx - x_center));
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;
}
/* center, horizontal */
if (gimp_image_snap_y (image, y_center, &ny,
MIN (epsilon_y, mindist_y),
snap_to_guides,
snap_to_grid,
snap_to_canvas))
{
mindist_y = ABS (ny - y_center);
*ty1 = RINT (y1 + (ny - y_center));
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)
{
snapped |= gimp_image_snap_distance (y1, nearest.y,
epsilon_y,
&mindist_y, ty1);
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
snapped |= gimp_image_snap_distance (x1, nearest.x,
epsilon_x,
&mindist_x, tx1);
}
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)
{
snapped |= gimp_image_snap_distance (x1, nearest.x,
epsilon_x,
&mindist_x, tx1);
}
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)
{
snapped |= gimp_image_snap_distance (x1, nearest.x,
epsilon_x,
&mindist_x, tx1);
}
if (gimp_stroke_nearest_intersection_get (stroke, &coords1, &coords2,
1.0, &nearest,
NULL, NULL, NULL) >= 0)
{
snapped |= gimp_image_snap_distance (y1, nearest.y,
epsilon_y,
&mindist_y, ty1);
}
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)
{
snapped |= gimp_image_snap_distance (y1, nearest.y,
epsilon_y,
&mindist_y, ty1);
}
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;
}
}
/* center */
coords1.x = x_center;
coords1.y = y_center;
if (gimp_stroke_nearest_point_get (stroke, &coords1, 1.0,
&nearest,
NULL, NULL, NULL) >= 0)
{
if (gimp_image_snap_distance (x_center, nearest.x,
epsilon_x,
&mindist_x, &nx))
{
mindist_x = ABS (nx - x_center);
*tx1 = RINT (x1 + (nx - x_center));
snapped = TRUE;
}
if (gimp_image_snap_distance (y_center, nearest.y,
epsilon_y,
&mindist_y, &ny))
{
mindist_y = ABS (ny - y_center);
*ty1 = RINT (y1 + (ny - y_center));
snapped = TRUE;
}
}
}
}
return snapped;
}
/* private functions */
/**
* gimp_image_snap_distance:
* @unsnapped: One coordinate of the unsnapped position
* @nearest: One coordinate of a snapping position candidate
* @epsilon: The snapping threshold
* @mindist: The distance to the currently closest snapping target
* @target: The currently closest snapping target
*
* Finds out if snapping occurs from position to a snapping candidate
* and sets the target accordingly.
*
* Return value: %TRUE if snapping occurred, %FALSE otherwise
*/
static gboolean
gimp_image_snap_distance (const gdouble unsnapped,
const gdouble nearest,
const gdouble epsilon,
gdouble *mindist,
gdouble *target)
{
const gdouble dist = ABS (nearest - unsnapped);
if (dist < MIN (epsilon, *mindist))
{
*mindist = dist;
*target = nearest;
return TRUE;
}
return FALSE;
}