PIKApp/pdb/groups/selection.pdb

# PIKA - Photo and Image Kooker Application
# 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/>.

# "Perlized" from C source by Manish Singh <yosh@gimp.org>

sub selection_bounds {
    $blurb = 'Find the bounding box of the current selection.';

    $help = <<'HELP';
This procedure returns whether there is a selection for the specified image. If
there is one, the upper left and lower right corners of the bounding box are
returned. These coordinates are relative to the image. Please note that the
pixel specified by the lower right coordinate of the bounding box is not
part of the selection. The selection ends at the upper left corner of this
pixel. This means the width of the selection can be calculated as (x2 - x1),
its height as (y2 - y1).
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    @outargs = (
	{ name => 'non_empty', type => 'boolean', void_ret => 1,
	  desc => 'TRUE if there is a selection' },
	{ name => 'x1', type => 'int32',
	  desc => 'x coordinate of upper left corner of selection bounds' },
	{ name => 'y1', type => 'int32',
	  desc => 'y coordinate of upper left corner of selection bounds' },
	{ name => 'x2', type => 'int32',
	  desc => 'x coordinate of lower right corner of selection bounds' },
	{ name => 'y2', type => 'int32',
	  desc => 'y coordinate of lower right corner of selection bounds' }
    );

    %invoke = (
	code => <<'CODE'
{
  gint x, y, w, h;

  non_empty = pika_item_bounds (PIKA_ITEM (pika_image_get_mask (image)),
                                &x, &y, &w, &h);

  x1 = x;
  y1 = y;
  x2 = x + w;
  y2 = y + h;
}
CODE
    );
}

sub selection_value {
    $blurb = 'Find the value of the selection at the specified coordinates.';

    $help = <<'HELP';
This procedure returns the value of the selection at the specified coordinates.
If the coordinates lie out of bounds, 0 is returned.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' },
	{ name => 'x', type => 'int32',
	  desc => 'x coordinate of value' },
	{ name => 'y', type => 'int32',
	  desc => 'y coordinate of value' }
    );

    @outargs = (
	{ name => 'value', type => '0 <= int32 <= 255',
	  desc => 'Value of the selection' }
    );

    %invoke = (
	code => <<'CODE'
{
  gdouble val;

  val= pika_pickable_get_opacity_at (PIKA_PICKABLE (pika_image_get_mask (image)),
                                     x, y);

  value = ROUND (CLAMP (val, 0.0, 1.0) * 255.0);
}
CODE
    );
}

sub selection_is_empty {
    $blurb = 'Determine whether the selection is empty.';

    $help = <<'HELP';
This procedure returns TRUE if the selection for the specified image is empty.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    @outargs = (
	{ name => 'is_empty', type => 'boolean',
	  desc => 'Is the selection empty?' }
    );

    %invoke = (
	code => <<'CODE'
{
  is_empty = pika_channel_is_empty (pika_image_get_mask (image));
}
CODE
    );
}

sub selection_translate {
    $blurb = 'Translate the selection by the specified offsets.';

    $help = <<'HELP';
This procedure actually translates the selection for the specified image by the
specified offsets. Regions that are translated from beyond the bounds of the
image are set to empty. Valid regions of the selection which are translated
beyond the bounds of the image because of this call are lost.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' },
	{ name => 'offx', type => 'int32',
	  desc => 'x offset for translation' },
	{ name => 'offy', type => 'int32',
	  desc => 'y offset for translation' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_item_translate (PIKA_ITEM (pika_image_get_mask (image)),
                       offx, offy, TRUE);
}
CODE
    );
}

sub selection_float {
    $blurb = <<'BLURB';
Float the selection from the specified drawable with initial offsets as
specified.
BLURB

    $help = <<'HELP';
This procedure determines the region of the specified drawable that lies
beneath the current selection. The region is then cut from the drawable and the
resulting data is made into a new layer which is instantiated as a floating
selection. The offsets allow initial positioning of the new floating selection.
HELP

    &std_pdb_misc;

    $lib_private = 1;

    @inargs = (
        { name => 'drawables', type => 'itemarray',
	  desc => 'The drawables from which to float selection',
          no_validate => 1,
          array => { name => 'num_drawables',
                     type => '1 <= int32',
                     desc => "The number of drawables" } },
	{ name => 'offx', type => 'int32',
	  desc => 'x offset for translation' },
	{ name => 'offy', type => 'int32',
	  desc => 'y offset for translation' }
    );

    @outargs = (
	{ name => 'layer', type => 'layer',
	  desc => 'The floated layer' }
    );

    %invoke = (
	code => <<'CODE'
{
  PikaImage *image = NULL;
  gint       i;

  if (num_drawables < 1)
    {
      success = FALSE;
    }
  else
    {
      for (i = 0; i < num_drawables; i++)
        {
          if (! pika_pdb_item_is_attached (PIKA_ITEM (drawables[i]), NULL,
                                           PIKA_PDB_ITEM_CONTENT, error) ||
              pika_pdb_item_is_group (PIKA_ITEM (drawables[i]), error)   ||
              (image && image != pika_item_get_image (PIKA_ITEM (drawables[i]))))
            {
              success = FALSE;
              break;
            }
          else
            {
              image = pika_item_get_image (PIKA_ITEM (drawables[i]));
            }
        }
    }

  if (success)
    {
      GList *drawable_list = NULL;

      for (i = 0; i < num_drawables; i++)
        drawable_list = g_list_prepend (drawable_list, (gpointer) drawables[i]);

      layer = pika_selection_float (PIKA_SELECTION (pika_image_get_mask (image)),
                                    drawable_list, context, TRUE, offx, offy,
                                    error);
      g_list_free (drawable_list);
      if (! layer)
        success = FALSE;
    }
}
CODE
    );
}

sub selection_invert {
    $blurb = 'Invert the selection mask.';

    $help = <<'HELP';
This procedure inverts the selection mask. For every pixel in the selection
channel, its new value is calculated as (255 - old-value).
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_channel_invert (pika_image_get_mask (image), TRUE);
}
CODE
    );
}

sub selection_sharpen {
    $blurb = 'Sharpen the selection mask.';

    $help = <<'HELP';
This procedure sharpens the selection mask. For every pixel in the selection
channel, if the value is > 127, the new pixel is assigned a value of 255.
This removes any "anti-aliasing" that might exist in the selection mask's
boundary.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_channel_sharpen (pika_image_get_mask (image), TRUE);
}
CODE
    );
}

sub selection_all {
    $blurb = 'Select all of the image.';

    $help = <<'HELP';
This procedure sets the selection mask to completely encompass the image.
Every pixel in the selection channel is set to 255.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_channel_all (pika_image_get_mask (image), TRUE);
}
CODE
    );
}

sub selection_none {
    $blurb = 'Deselect the entire image.';

    $help = <<'HELP';
This procedure deselects the entire image. Every pixel in the selection channel
is set to 0.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_channel_clear (pika_image_get_mask (image), NULL, TRUE);
}
CODE
    );
}

sub selection_feather {
    $blurb = "Feather the image's selection";

    $help = <<'HELP';
This procedure feathers the selection. Feathering is implemented
using a gaussian blur.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' },
	{ name => 'radius', type => '0 <= float',
	  desc => 'Radius of feather (in pixels)' }
    );

    %invoke = (
	code => <<'CODE'
{
  /* FIXME: "edge-lock" hardcoded to  TRUE */
  pika_channel_feather (pika_image_get_mask (image),
                        radius, radius, TRUE, TRUE);
}
CODE
    );
}

sub selection_border {
    $blurb = "Border the image's selection";

    $help .= <<'HELP';
This procedure borders the selection. Bordering creates a new
selection which is defined along the boundary of the previous
selection at every point within the specified radius.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' },
	{ name => 'radius', type => '0 <= int32',
	  desc => 'Radius of border (in pixels)' }
    );

    %invoke = (
	code => <<'CODE'
{
  /* FIXME: "style" and "edge-lock" hardcoded to SMOOTH and TRUE, respectively. */
  pika_channel_border (pika_image_get_mask (image),
                       radius, radius,
                       PIKA_CHANNEL_BORDER_STYLE_SMOOTH,
                       TRUE, TRUE);
}
CODE
    );
}

sub selection_grow {
    $blurb = "Grow the image's selection";

    $help .= <<'HELP';
This procedure grows the selection. Growing involves expanding the
boundary in all directions by the specified pixel amount.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' },
	{ name => 'steps', type => '0 <= int32',
	  desc => 'Steps of grow (in pixels)' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_channel_grow (pika_image_get_mask (image),
                     steps, steps, TRUE);
}
CODE
    );
}

sub selection_shrink {
    $blurb = "Shrink the image's selection";

    $help .= <<'HELP';
This procedure shrinks the selection. Shrinking involves trimming the
existing selection boundary on all sides by the specified number of
pixels.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' },
	{ name => 'steps', type => '0 <= int32',
	  desc => 'Steps of shrink (in pixels)' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_channel_shrink (pika_image_get_mask (image),
                       steps, steps, FALSE, TRUE);
}
CODE
    );
}

sub selection_flood {
    $blurb = "Remove holes from the image's selection";

    $help .= <<'HELP';
This procedure removes holes from the selection, that can come from 
selecting a patchy area with the Fuzzy Select Tool. 
In technical terms this procedure floods the selection. 
See the Algorithms page in the developer wiki for details.
HELP

    $author = 'Ell';
    $copyright = 'Ell';
    $date = '2016';
    $since = '2.10';

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    %invoke = (
	code => <<'CODE'
{
  pika_channel_flood (pika_image_get_mask (image), TRUE);
}
CODE
    );
}

sub selection_save {
    $blurb = 'Copy the selection mask to a new channel.';

    $help = <<'HELP';
This procedure copies the selection mask and stores the content in a new
channel. The new channel is automatically inserted into the image's list of
channels.
HELP

    &std_pdb_misc;

    @inargs = (
	{ name => 'image', type => 'image',
	  desc => 'The image' }
    );

    @outargs = (
	{ name => 'channel', type => 'channel',
	  desc => 'The new channel' }
    );

    %invoke = (
        headers => [qw("core/pikaselection.h") ],
	code    => <<'CODE'
{
  channel = PIKA_CHANNEL (pika_item_duplicate (PIKA_ITEM (pika_image_get_mask (image)),
                                               PIKA_TYPE_CHANNEL));

  if (channel)
    {
      /*  saved selections are not visible by default  */
      pika_item_set_visible (PIKA_ITEM (channel), FALSE, FALSE);

      pika_image_add_channel (image, channel,
                              PIKA_IMAGE_ACTIVE_PARENT, -1, TRUE);
    }
  else
    success = FALSE;
}
CODE
    );
}

@headers = qw("libpikamath/pikamath.h"
              "core/pikapickable.h"
              "pikapdb-utils.h"
              "pika-intl.h");

@procs = qw(selection_bounds selection_value selection_is_empty
	    selection_translate selection_float
	    selection_invert selection_sharpen selection_all selection_none
	    selection_feather selection_border selection_grow selection_shrink
	    selection_flood
	    selection_save);

%exports = (app => [@procs], lib => [@procs]);

$desc = 'Image mask';
$doc_title = 'pikaselection';
$doc_short_desc = 'Functions for manipulating selections.';
$doc_long_desc = 'Functions for manipulating selections.';

1;