gimp/app/core/gimpimage-snap.c

1234 lines
43 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 <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <gdk-pixbuf/gdk-pixbuf.h>
#include <gegl.h>
#include "libgimpmath/gimpmath.h"
#include "core-types.h"
#include "gimp.h"
#include "gimpgrid.h"
#include "gimpguide.h"
#include "gimpimage.h"
#include "gimplayer.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,
GimpImageSnapData *snapping_data,
gdouble x,
gdouble *tx,
gdouble epsilon_x,
gboolean snap_to_guides,
gboolean snap_to_grid,
gboolean snap_to_canvas,
gboolean snap_to_bbox,
gboolean snap_to_equidistance,
GimpAlignmentType alignment_side)
{
gdouble mindist = G_MAXDOUBLE;
gdouble mindist_t = 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 || snap_to_bbox || snap_to_equidistance))
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);
}
if (snap_to_bbox)
{
GList *selected_layers_list;
GList *layers_list;
gdouble gcx;
gint gx, gy, gw, gh;
gboolean not_in_selected_set;
gboolean snapped_2;
selected_layers_list = gimp_image_get_selected_layers (image);
layers_list = gimp_image_get_layer_list (image);
not_in_selected_set = TRUE;
snapped_2 = FALSE;
for (GList *iter = layers_list; iter; iter = iter->next)
{
if (!gimp_item_is_visible (iter->data))
continue;
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
gcx = (gdouble) gx + (gdouble) gw/2.0;
not_in_selected_set = TRUE;
for (GList *iter2 = selected_layers_list; iter2; iter2 = iter2->next)
{
if (iter2->data == iter->data)
not_in_selected_set = FALSE;
}
if ((gint) x >= gx && (gint) x <= (gx+gw) && not_in_selected_set)
{
snapped_2 |= gimp_image_snap_distance (x, (gdouble) gx,
epsilon_x,
&mindist, tx);
snapped_2 |= gimp_image_snap_distance (x, (gdouble) gx+gw,
epsilon_x,
&mindist, tx);
snapped_2 |= gimp_image_snap_distance (x, gcx,
epsilon_x,
&mindist, tx);
if (snapped_2)
{
snapped |= snapped_2;
snapped_2 = FALSE;
snapping_data->snapped_layer_horizontal = iter->data;
snapping_data->snapped_side_horizontal = alignment_side;
}
}
}
mindist_t = mindist;
g_list_free (layers_list);
}
if (snap_to_equidistance)
{
GList *layers_list = gimp_image_get_layer_list (image);
GList *selected_layers_list = gimp_image_get_selected_layers (image);
GimpLayer *near_layer1 = NULL;
gint gx, gy, gw, gh;
gint selected_set_y1 = G_MAXINT;
gint selected_set_y2 = G_MININT;
gint left_box_x2 = G_MININT;
gint left_box_x1 = 0;
gint left_box2_x2 = G_MININT;
gint right_box_x1 = G_MAXINT;
gint right_box_x2 = 0;
gint right_box2_x1 = G_MAXINT;
gint near_box_y1 = 0;
gint near_box_y2 = 0;
for (GList *iter = selected_layers_list; iter; iter = iter->next)
{
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
if (gy < selected_set_y1)
selected_set_y1 = gy;
if ((gy+gh) > selected_set_y2)
selected_set_y2 = gy+gh;
}
for (GList *iter = layers_list; iter; iter = iter->next)
{
if (!gimp_item_is_visible (iter->data))
continue;
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
if ((gy >= selected_set_y1 && gy <= selected_set_y2) ||
((gy+gh) >= selected_set_y1 && (gy+gh) <= selected_set_y2) ||
(selected_set_y1 >= gy && selected_set_y1 <= (gy+gh)) ||
(selected_set_y2 >= gy && selected_set_y2 <= (gy+gh)))
{
if (alignment_side == GIMP_ALIGN_LEFT &&
(gx+gw) < (gint) x && (gx+gw) > left_box_x2)
{
left_box_x2 = gx+gw;
left_box_x1 = gx;
near_box_y1 = gy;
near_box_y2 = gy+gh;
near_layer1 = iter->data;
}
else if (alignment_side == GIMP_ALIGN_RIGHT &&
gx > (gint) x && gx < right_box_x1)
{
right_box_x1 = gx;
right_box_x2 = gx+gw;
near_box_y1 = gy;
near_box_y2 = gy+gh;
near_layer1 = iter->data;
}
}
}
if (left_box_x2 != G_MININT || right_box_x1 != G_MAXINT)
{
for (GList *iter = layers_list; iter; iter = iter->next)
{
if (!gimp_item_is_visible (iter->data))
continue;
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
if ((gy >= near_box_y1 && gy <= near_box_y2) ||
((gy+gh) >= near_box_y1 && (gy+gh) <= near_box_y2) ||
(near_box_y1 >= gy && near_box_y1 <= (gy+gh)) ||
(near_box_y2 >= gy && near_box_y2 <= (gy+gh)))
{
if (alignment_side == GIMP_ALIGN_LEFT && (gx+gw) < left_box_x1)
{
left_box2_x2 = gx+gw;
if (gimp_image_snap_distance (x, (gdouble) (left_box_x2 + (left_box_x1 - left_box2_x2)),
epsilon_x,
&mindist, tx) ||
*tx == (left_box_x2 + (left_box_x1 - left_box2_x2)))
{
snapped |= TRUE;
snapping_data->equidistance_side_horizontal = GIMP_ALIGN_LEFT;
snapping_data->near_layer_horizontal1 = near_layer1;
snapping_data->near_layer_horizontal2 = iter->data;
break;
}
}
else if (alignment_side == GIMP_ALIGN_RIGHT && gx > right_box_x2)
{
right_box2_x1 = gx;
if (gimp_image_snap_distance (x, (gdouble) (right_box_x1 - (right_box2_x1 - right_box_x2)),
epsilon_x,
&mindist, tx) ||
*tx == (right_box_x1 - (right_box2_x1 - right_box_x2)))
{
snapped |= TRUE;
snapping_data->equidistance_side_horizontal = GIMP_ALIGN_RIGHT;
snapping_data->near_layer_horizontal1 = near_layer1;
snapping_data->near_layer_horizontal2 = iter->data;
break;
}
}
}
}
}
g_list_free (layers_list);
}
if (mindist_t != G_MAXDOUBLE && mindist_t > mindist)
snapping_data->snapped_side_horizontal = GIMP_ARRANGE_HFILL;
return snapped;
}
gboolean
gimp_image_snap_y (GimpImage *image,
GimpImageSnapData *snapping_data,
gdouble y,
gdouble *ty,
gdouble epsilon_y,
gboolean snap_to_guides,
gboolean snap_to_grid,
gboolean snap_to_canvas,
gboolean snap_to_bbox,
gboolean snap_to_equidistance,
GimpAlignmentType alignment_side)
{
gdouble mindist = G_MAXDOUBLE;
gdouble mindist_t = 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 || snap_to_bbox || snap_to_equidistance))
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);
}
if (snap_to_bbox)
{
GList *selected_layers_list;
GList *layers_list;
gdouble gcy;
gint gx, gy, gw, gh;
gboolean not_in_selected_set;
gboolean snapped_2;
selected_layers_list = gimp_image_get_selected_layers (image);
layers_list = gimp_image_get_layer_list (image);
not_in_selected_set = TRUE;
snapped_2 = FALSE;
for (GList *iter = layers_list; iter; iter = iter->next)
{
if (!gimp_item_is_visible (iter->data))
continue;
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
gcy = (gdouble) gy + (gdouble) gh/2.0;
not_in_selected_set = TRUE;
for (GList *iter2 = selected_layers_list; iter2; iter2 = iter2->next)
{
if (iter2->data == iter->data)
not_in_selected_set = FALSE;
}
if ((gint) y >= gy && (gint) y <= (gy+gh) && not_in_selected_set)
{
snapped_2 |= gimp_image_snap_distance (y, (gdouble) gy,
epsilon_y,
&mindist, ty);
snapped_2 |= gimp_image_snap_distance (y, (gdouble) gy+gh,
epsilon_y,
&mindist, ty);
snapped_2 |= gimp_image_snap_distance (y, gcy,
epsilon_y,
&mindist, ty);
if (snapped_2)
{
snapped |= snapped_2;
snapped_2 = FALSE;
snapping_data->snapped_layer_vertical = iter->data;
snapping_data->snapped_side_vertical = alignment_side;
}
}
}
mindist_t = mindist;
g_list_free (layers_list);
}
if (snap_to_equidistance)
{
GList *layers_list = gimp_image_get_layer_list (image);
GList *selected_layers_list = gimp_image_get_selected_layers (image);
GimpLayer *near_layer1 = NULL;
gint gx, gy, gw, gh;
gint selected_set_x1 = G_MAXINT;
gint selected_set_x2 = G_MININT;
gint up_box_y2 = G_MININT;
gint up_box_y1 = 0;
gint up_box2_y2 = G_MININT;
gint down_box_y1 = G_MAXINT;
gint down_box_y2 = 0;
gint down_box2_y1 = G_MAXINT;
gint near_box_x1 = 0;
gint near_box_x2 = 0;
for (GList *iter = selected_layers_list; iter; iter = iter->next)
{
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
if (gx < selected_set_x1)
selected_set_x1 = gx;
if ((gx+gw) > selected_set_x2)
selected_set_x2 = gx+gw;
}
for (GList *iter = layers_list; iter; iter = iter->next)
{
if (!gimp_item_is_visible (iter->data))
continue;
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
if ((gx >= selected_set_x1 && gx <= selected_set_x2) ||
((gx+gw) >= selected_set_x1 && (gx+gw) <= selected_set_x2) ||
(selected_set_x1 >= gx && selected_set_x1 <= (gx+gw)) ||
(selected_set_x2 >= gx && selected_set_x2 <= (gx+gw)))
{
if (alignment_side == GIMP_ALIGN_TOP &&
(gy+gh) < (gint) y && (gy+gh) > up_box_y2)
{
up_box_y2 = gy+gh;
up_box_y1 = gy;
near_box_x1 = gx;
near_box_x2 = gx+gw;
near_layer1 = iter->data;
}
else if (alignment_side == GIMP_ALIGN_BOTTOM &&
gy > (gint) y && gy < down_box_y1)
{
down_box_y1 = gy;
down_box_y2 = gy+gh;
near_box_x1 = gx;
near_box_x2 = gx+gw;
near_layer1 = iter->data;
}
}
}
if (up_box_y2 != G_MININT || down_box_y1 != G_MAXINT)
{
for (GList *iter = layers_list; iter; iter = iter->next)
{
if (!gimp_item_is_visible (iter->data))
continue;
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
if ((gx >= near_box_x1 && gx <= near_box_x2) ||
((gx+gw) >= near_box_x1 && (gx+gw) <= near_box_x2) ||
(near_box_x1 >= gx && near_box_x1 <= (gx+gw)) ||
(near_box_x2 >= gx && near_box_x2 <= (gx+gw)))
{
if (alignment_side == GIMP_ALIGN_TOP && (gy+gh) < up_box_y1)
{
up_box2_y2 = gy+gh;
if (gimp_image_snap_distance (y, (gdouble) (up_box_y2 + (up_box_y1 - up_box2_y2)),
epsilon_y,
&mindist, ty) ||
*ty == (up_box_y2 + (up_box_y1 - up_box2_y2)))
{
snapped |= TRUE;
snapping_data->equidistance_side_vertical = GIMP_ALIGN_TOP;
snapping_data->near_layer_vertical1 = near_layer1;
snapping_data->near_layer_vertical2 = iter->data;
break;
}
}
else if (alignment_side == GIMP_ALIGN_BOTTOM && gy > down_box_y2)
{
down_box2_y1 = gy;
if (gimp_image_snap_distance (y, (gdouble) (down_box_y1 - (down_box2_y1 - down_box_y2)),
epsilon_y,
&mindist, ty) ||
*ty == (down_box_y1 - (down_box2_y1 - down_box_y2)))
{
snapped |= TRUE;
snapping_data->equidistance_side_vertical = GIMP_ALIGN_BOTTOM;
snapping_data->near_layer_vertical1 = near_layer1;
snapping_data->near_layer_vertical2 = iter->data;
break;
}
}
}
}
}
g_list_free (layers_list);
}
if (mindist_t != G_MAXDOUBLE && mindist_t > mindist)
snapping_data->snapped_side_vertical = GIMP_ARRANGE_HFILL;
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 snap_to_bbox,
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_selected_vectors (image))
snap_to_vectors = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas || snap_to_vectors || snap_to_bbox))
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)
{
GList *selected_vectors = gimp_image_get_selected_vectors (image);
GList *iter;
GimpStroke *stroke = NULL;
GimpCoords coords = { 0, 0, 0, 0, 0 };
coords.x = x;
coords.y = y;
for (iter = selected_vectors; iter; iter = iter->next)
{
GimpVectors *vectors = iter->data;
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);
}
}
}
}
if (snap_to_bbox)
{
GList *layers_list = gimp_image_get_layer_list (image);
gdouble gcx, gcy;
gint gx, gy, gw, gh;
for (GList *iter = layers_list; iter; iter = iter->next)
{
if (!gimp_item_is_visible (iter->data))
continue;
gimp_item_bounds (iter->data, &gx, &gy, &gw, &gh);
gimp_item_get_offset (iter->data, &gx, &gy);
gcx = (gdouble) gx + (gdouble) gw/2.0;
gcy = (gdouble) gy + (gdouble) gh/2.0;
if ((gint) x >= gx && (gint) x <= (gx+gw))
{
snapped |= gimp_image_snap_distance (x, (gdouble) gx,
epsilon_x,
&mindist_x, tx);
snapped |= gimp_image_snap_distance (x, (gdouble) gx+gw,
epsilon_x,
&mindist_x, tx);
snapped |= gimp_image_snap_distance (x, gcx,
epsilon_x,
&mindist_x, tx);
}
if ((gint) y >= gy && (gint) y <= (gy+gh))
{
snapped |= gimp_image_snap_distance (y, (gdouble) gy,
epsilon_y,
&mindist_y, ty);
snapped |= gimp_image_snap_distance (y, (gdouble) gy+gh,
epsilon_y,
&mindist_y, ty);
snapped |= gimp_image_snap_distance (y, gcy,
epsilon_y,
&mindist_y, ty);
}
}
g_list_free (layers_list);
}
return snapped;
}
gboolean
gimp_image_snap_rectangle (GimpImage *image,
GimpImageSnapData *snapping_data,
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,
gboolean snap_to_bbox,
gboolean snap_to_equidistance)
{
gdouble nx, ny;
gdouble mindist_x = G_MAXDOUBLE;
gdouble mindist_y = G_MAXDOUBLE;
gdouble mindist_t = G_MAXDOUBLE;
gdouble mindist_tx = G_MAXDOUBLE;
gdouble mindist_ty = G_MAXDOUBLE;
gdouble x_center = (x1 + x2) / 2.0;
gdouble y_center = (y1 + y2) / 2.0;
gboolean snapped = FALSE;
GimpAlignmentType alignment_side;
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_selected_vectors (image))
snap_to_vectors = FALSE;
if (! (snap_to_guides || snap_to_grid || snap_to_canvas || snap_to_vectors || snap_to_bbox || snap_to_equidistance))
return FALSE;
/* center, vertical */
if (gimp_image_snap_x (image, snapping_data, x_center, &nx,
MIN (epsilon_x, mindist_x),
snap_to_guides,
snap_to_grid,
snap_to_canvas,
snap_to_bbox,
FALSE,
GIMP_ALIGN_VCENTER))
{
mindist_x = ABS (nx - x_center);
*tx1 = RINT (x1 + (nx - x_center));
snapped = TRUE;
}
/* left edge */
if (gimp_image_snap_x (image, snapping_data, x1, &nx,
MIN (epsilon_x, mindist_x),
snap_to_guides,
snap_to_grid,
snap_to_canvas,
snap_to_bbox,
snap_to_equidistance,
GIMP_ALIGN_LEFT))
{
mindist_x = ABS (nx - x1);
mindist_t = mindist_x;
*tx1 = nx;
snapped = TRUE;
}
alignment_side = snapping_data->equidistance_side_horizontal;
if (mindist_t > mindist_x && alignment_side == GIMP_ALIGN_VCENTER)
snapping_data->equidistance_side_horizontal = GIMP_ARRANGE_HFILL;
mindist_t = mindist_x;
/* right edge */
if (gimp_image_snap_x (image, snapping_data, x2, &nx,
MIN (epsilon_x, mindist_x),
snap_to_guides,
snap_to_grid,
snap_to_canvas,
snap_to_bbox,
snap_to_equidistance,
GIMP_ALIGN_RIGHT))
{
mindist_x = ABS (nx - x2);
*tx1 = RINT (x1 + (nx - x2));
snapped = TRUE;
}
alignment_side = snapping_data->equidistance_side_horizontal;
if (mindist_t > mindist_x && (alignment_side == GIMP_ALIGN_LEFT || alignment_side == GIMP_ALIGN_VCENTER))
snapping_data->equidistance_side_horizontal = GIMP_ARRANGE_HFILL;
mindist_t = G_MAXDOUBLE;
/* center, horizontal */
if (gimp_image_snap_y (image, snapping_data, y_center, &ny,
MIN (epsilon_y, mindist_y),
snap_to_guides,
snap_to_grid,
snap_to_canvas,
snap_to_bbox,
FALSE,
GIMP_ALIGN_HCENTER))
{
mindist_y = ABS (ny - y_center);
*ty1 = RINT (y1 + (ny - y_center));
snapped = TRUE;
}
/* top edge */
if (gimp_image_snap_y (image, snapping_data, y1, &ny,
MIN (epsilon_y, mindist_y),
snap_to_guides,
snap_to_grid,
snap_to_canvas,
snap_to_bbox,
snap_to_equidistance,
GIMP_ALIGN_TOP))
{
mindist_y = ABS (ny - y1);
mindist_t = mindist_y;
*ty1 = ny;
snapped = TRUE;
}
alignment_side = snapping_data->equidistance_side_vertical;
if (mindist_t > mindist_y && alignment_side == GIMP_ALIGN_HCENTER)
snapping_data->equidistance_side_vertical = GIMP_ARRANGE_HFILL;
mindist_t = mindist_y;
/* bottom edge */
if (gimp_image_snap_y (image, snapping_data, y2, &ny,
MIN (epsilon_y, mindist_y),
snap_to_guides,
snap_to_grid,
snap_to_canvas,
snap_to_bbox,
snap_to_equidistance,
GIMP_ALIGN_BOTTOM))
{
mindist_y = ABS (ny - y2);
*ty1 = RINT (y1 + (ny - y2));
snapped = TRUE;
}
alignment_side = snapping_data->equidistance_side_vertical;
if (mindist_t > mindist_y && (alignment_side == GIMP_ALIGN_HCENTER || alignment_side == GIMP_ALIGN_TOP))
snapping_data->equidistance_side_vertical = GIMP_ARRANGE_HFILL;
mindist_tx = mindist_x;
mindist_ty = mindist_y;
if (snap_to_vectors)
{
GList *selected_vectors = gimp_image_get_selected_vectors (image);
GList *iter;
GimpStroke *stroke = NULL;
GimpCoords coords1 = GIMP_COORDS_DEFAULT_VALUES;
GimpCoords coords2 = GIMP_COORDS_DEFAULT_VALUES;
for (iter = selected_vectors; iter; iter = iter->next)
{
GimpVectors *vectors = iter->data;
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;
}
}
}
}
if (ROUND (mindist_y) < ROUND (mindist_ty))
{
snapping_data->equidistance_side_vertical = GIMP_ARRANGE_HFILL;
snapping_data->snapped_side_vertical = GIMP_ARRANGE_HFILL;
}
if (ROUND (mindist_x) < ROUND (mindist_tx))
{
snapping_data->equidistance_side_horizontal = GIMP_ARRANGE_HFILL;
snapping_data->snapped_side_horizontal = GIMP_ARRANGE_HFILL;
}
}
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.
*
* Returns: %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;
}