PIKApp/pdb/groups/item_transform.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>

# Item Transformations

# shortcuts

sub transform_invoke {
    my ($progress_text, $assemble_matrix, $check) = @_;
    my $success_check = <<"CODE";
  success = pika_pdb_item_is_attached (item, NULL,
                                       PIKA_PDB_ITEM_CONTENT |
                                       PIKA_PDB_ITEM_POSITION, error);
CODE

    if ($check) {
        $success_check = <<"CODE"
  success = (pika_pdb_item_is_attached (item, NULL,
                                        PIKA_PDB_ITEM_CONTENT |
                                        PIKA_PDB_ITEM_POSITION, error) &&
	     $check);
CODE
    }

    %invoke = (
        code => <<"CODE"
{
  gint x, y, width, height;

$success_check

  if (success &&
      pika_item_mask_intersect (item, &x, &y, &width, &height))
    {
      PikaPDBContext *pdb_context = PIKA_PDB_CONTEXT (context);
      PikaImage      *image       = pika_item_get_image (item);
      PikaChannel    *mask        = pika_image_get_mask (image);
      PikaMatrix3     matrix;
      gint            off_x, off_y;

      pika_item_get_offset (item, &off_x, &off_y);
      x += off_x;
      y += off_y;

      /* Assemble the transformation matrix */
$assemble_matrix

      if (progress)
        pika_progress_start (progress, FALSE, _(\"$progress_text\"));

      if (PIKA_IS_DRAWABLE (item)                             &&
          item != PIKA_ITEM (mask)                            &&
          ! pika_viewable_get_children (PIKA_VIEWABLE (item)) &&
          ! pika_channel_is_empty (mask))
        {
          PikaDrawable *drawable;

          drawable = pika_drawable_transform_affine (PIKA_DRAWABLE (item),
                                                     context, &matrix,
                                                     pdb_context->transform_direction,
                                                     pdb_context->interpolation,
                                                     pdb_context->transform_resize,
                                                     progress);

          if (drawable)
            item = PIKA_ITEM (drawable);
          else
            success = FALSE;
        }
      else
        {
          pika_item_transform (item, context, &matrix,
                               pdb_context->transform_direction,
                               pdb_context->interpolation,
                               pika_item_get_clip (
                                 item, pdb_context->transform_resize),
                               progress);
        }

      if (progress)
        pika_progress_end (progress);
    }
}
CODE
    )
}

# The defs

sub item_transform_translate {
    $blurb = 'Translate the item by the specified offsets.';

    $help = <<'HELP';
This procedure translates the item by the amounts specified in the
off_x and off_y arguments. These can be negative, and are considered
offsets from the current position. The offsets will be rounded to the
nearest pixel unless the item is a path.
HELP

    &mitch_pdb_misc('2018', '2.10');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The item' },
	{ name => 'off_x', type => 'float',
	  desc => "Offset in x direction" },
	{ name => 'off_y', type => 'float',
	  desc => "Offset in y direction" }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The translated item' }
    );

    %invoke = (
	code => <<'CODE'
{
  if (pika_pdb_item_is_modifiable (item,
                                   PIKA_PDB_ITEM_POSITION, error))
    pika_item_translate (item, off_x, off_y, TRUE);
  else
    success = FALSE;
}
CODE
    );
}

sub item_transform_flip_simple {
    $blurb = <<'BLURB';
Flip the specified item either vertically or horizontally.
BLURB

    $help = <<'HELP';
This procedure flips the specified item.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then flipped. If auto_center
is set to TRUE, the flip is around the selection's center. Otherwise,
the coordinate of the axis needs to be specified. The return value is
the ID of the flipped floating selection.


If there is no selection or the item is not a drawable, the entire
item will be flipped around its center if auto_center is set to TRUE,
otherwise the coordinate of the axis needs to be specified.
The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2004', '2.2');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
        { name => 'flip_type',
	  type => 'enum PikaOrientationType (no PIKA_ORIENTATION_UNKNOWN)',
          desc => 'Type of flip' },
        { name => 'auto_center', type => 'boolean',
          desc => 'Whether to automatically position the axis in the selection center' },
        { name => 'axis', type => 'float',
          desc => 'coord. of flip axis' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The flipped item' }
    );

    %invoke = (
        code => <<'CODE'
{
  gint x, y, width, height;

  success = pika_pdb_item_is_attached (item, NULL,
                                       PIKA_PDB_ITEM_CONTENT |
                                       PIKA_PDB_ITEM_POSITION, error);

  if (success &&
      pika_item_mask_intersect (item, &x, &y, &width, &height))
    {
      PikaPDBContext *pdb_context = PIKA_PDB_CONTEXT (context);
      PikaImage      *image       = pika_item_get_image (item);
      PikaChannel    *mask        = pika_image_get_mask (image);
      gint            off_x, off_y;

      pika_item_get_offset (item, &off_x, &off_y);
      x += off_x;
      y += off_y;

      pika_transform_get_flip_axis (x, y, width, height,
                                    flip_type, auto_center, &axis);

      if (PIKA_IS_DRAWABLE (item)                             &&
          item != PIKA_ITEM (mask)                            &&
          ! pika_viewable_get_children (PIKA_VIEWABLE (item)) &&
          ! pika_channel_is_empty (mask))
        {
          PikaDrawable *drawable;

          drawable = pika_drawable_transform_flip (PIKA_DRAWABLE (item), context,
                                                   flip_type, axis,
                                                   pdb_context->transform_resize);

          if (drawable)
            item = PIKA_ITEM (drawable);
          else
            success = FALSE;
        }
      else
        {
          pika_item_flip (item, context,
                          flip_type, axis,
                          pika_item_get_clip (
                            item, pdb_context->transform_resize));
        }
    }
}
CODE
    );
}


sub item_transform_flip {
    $blurb = <<'BLURB';
Flip the specified item around a given line.
BLURB

    $help = <<'HELP';
This procedure flips the specified item.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then flipped. The axis to flip
around is specified by specifying two points from that line. The
return value is the ID of the flipped floating selection.


If there is no selection or the item is not a drawable, the entire
item will be flipped around the specified axis.
The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_interpolation(), pika_context_set_transform_direction(),
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
        { name => 'x0', type => 'float',
          desc => 'horz. coord. of one end of axis' },
        { name => 'y0', type => 'float',
          desc => 'vert. coord. of one end of axis' },
        { name => 'x1', type => 'float',
          desc => 'horz. coord. of other end of axis' },
        { name => 'y1', type => 'float',
          desc => 'vert. coord. of other end of axis' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The flipped item' }
    );

    transform_invoke ("Flipping", <<CODE);
      pika_matrix3_identity (&matrix);
      pika_transform_matrix_flip_free (&matrix, x0, y0, x1, y1);
CODE
}


sub item_transform_perspective {
    $blurb = <<'BLURB';
Perform a possibly non-affine transformation on the specified item.
BLURB

    $help = <<'HELP';
This procedure performs a possibly non-affine transformation on the
specified item by allowing the corners of the original bounding box to
be arbitrarily remapped to any values.


The 4 coordinates specify the new locations of each corner of the
original bounding box. By specifying these values, any affine
transformation (rotation, scaling, translation) can be affected.
Additionally, these values can be specified such that the resulting
transformed item will appear to have been projected via a perspective
transform.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then transformed as specified.
The return value is the ID of the transformed floating selection.


If there is no selection or the item is not a drawable, the entire
item will be transformed according to the specified mapping.

The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_interpolation(), pika_context_set_transform_direction(),
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
	{ name => 'x0', type => 'float',
	  desc => 'The new x coordinate of upper-left corner of original
		   bounding box' },
	{ name => 'y0', type => 'float',
	  desc => 'The new y coordinate of upper-left corner of original
		   bounding box' },
	{ name => 'x1', type => 'float',
	  desc => 'The new x coordinate of upper-right corner of original
		   bounding box' },
	{ name => 'y1', type => 'float',
	  desc => 'The new y coordinate of upper-right corner of original
		   bounding box' },
	{ name => 'x2', type => 'float',
	  desc => 'The new x coordinate of lower-left corner of original
		   bounding box' },
	{ name => 'y2', type => 'float',
	  desc => 'The new y coordinate of lower-left corner of original
		   bounding box' },
	{ name => 'x3', type => 'float',
	  desc => 'The new x coordinate of lower-right corner of original
		   bounding box' },
	{ name => 'y3', type => 'float',
	  desc => 'The new y coordinate of lower-right corner of original
		   bounding box' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The transformed item' }
    );

    transform_invoke ("Perspective", <<CODE);
      pika_matrix3_identity (&matrix);
      pika_transform_matrix_perspective (&matrix,
                                         x, y, width, height,
                                         x0, y0, x1, y1,
                                         x2, y2, x3, y3);
CODE
}


sub item_transform_rotate_simple {
    $blurb = <<'BLURB';
Rotate the specified item about given coordinates through the specified angle.
BLURB

    $help = <<'HELP';
This function rotates the specified item.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then rotated by the specified
amount. If auto_center is set to TRUE, the rotation is around the
selection's center. Otherwise, the coordinate of the center point
needs to be specified. The return value is the ID of the rotated
floating selection.


If there is no selection or the item is not a drawable, the entire
item will be rotated around its center if auto_center is set to TRUE,
otherwise the coordinate of the center point needs to be specified.

The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
        { name => 'rotate_type', type => 'enum PikaRotationType',
          desc => 'Type of rotation' },
        { name => 'auto_center', type => 'boolean',
          desc => 'Whether to automatically rotate around the selection center' },
        { name => 'center_x', type => 'float',
          desc => 'The hor. coordinate of the center of rotation' },
        { name => 'center_y', type => 'float',
          desc => 'The vert. coordinate of the center of rotation' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The rotated item' }
    );

    %invoke = (
        code => <<'CODE'
{
  gint x, y, width, height;

  success = pika_pdb_item_is_attached (item, NULL,
                                       PIKA_PDB_ITEM_CONTENT |
                                       PIKA_PDB_ITEM_POSITION, error);

  if (success &&
      pika_item_mask_intersect (item, &x, &y, &width, &height))
    {
      PikaPDBContext *pdb_context = PIKA_PDB_CONTEXT (context);
      PikaImage      *image       = pika_item_get_image (item);
      PikaChannel    *mask        = pika_image_get_mask (image);
      gint            off_x, off_y;

      pika_item_get_offset (item, &off_x, &off_y);
      x += off_x;
      y += off_y;

      pika_transform_get_rotate_center (x, y, width, height,
                                        auto_center, &center_x, &center_y);

      if (PIKA_IS_DRAWABLE (item)                             &&
          item != PIKA_ITEM (mask)                            &&
          ! pika_viewable_get_children (PIKA_VIEWABLE (item)) &&
          ! pika_channel_is_empty (mask))
        {
          PikaDrawable *drawable;

          drawable = pika_drawable_transform_rotate (PIKA_DRAWABLE (item),
                                                     context,
                                                     rotate_type,
                                                     center_x, center_y,
                                                     pdb_context->transform_resize);

          if (drawable)
            item = PIKA_ITEM (drawable);
          else
            success = FALSE;
        }
      else
        {
          pika_item_rotate (item, context,
                            rotate_type,
                            center_x, center_y,
                            pika_item_get_clip (
                              item, pdb_context->transform_resize));
        }
    }
}
CODE
    );
}


sub item_transform_rotate {
    $blurb = <<'BLURB';
Rotate the specified item about given coordinates through the
specified angle.
BLURB

    $help = <<'HELP';
This function rotates the specified item.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then rotated by the specified
amount. If auto_center is set to TRUE, the rotation is around the
selection's center. Otherwise, the coordinate of the center point
needs to be specified. The return value is the ID of the rotated
floating selection.


If there is no selection or the item is not a drawable, the entire
item will be rotated around its center if auto_center is set to TRUE,
otherwise the coordinate of the center point needs to be specified.

The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_interpolation(), pika_context_set_transform_direction(),
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
        { name => 'angle', type => 'float',
          desc => 'The angle of rotation (radians)' },
        { name => 'auto_center', type => 'boolean',
          desc => 'Whether to automatically rotate around the selection center' },
        { name => 'center_x', type => 'float',
          desc => 'The hor. coordinate of the center of rotation' },
        { name => 'center_y', type => 'float',
          desc => 'The vert. coordinate of the center of rotation' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The rotated item' }
    );

    transform_invoke ("Rotating", <<CODE);
      pika_matrix3_identity (&matrix);
      if (auto_center)
        pika_transform_matrix_rotate_rect (&matrix,
                                           x, y, width, height, angle);
      else
        pika_transform_matrix_rotate_center (&matrix,
                                             center_x, center_y, angle);
CODE
}


sub item_transform_scale {
    $blurb = 'Scale the specified item.';

    $help = <<'HELP';
This procedure scales the specified item.


The 2 coordinates specify the new locations of the top-left and
bottom-roght corners of the original bounding box.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then scaled as specified.  The
return value is the ID of the scaled floating selection.


If there is no selection or the item is not a drawable, the entire
item will be scaled according to the specified coordinates.

The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_interpolation(), pika_context_set_transform_direction(),
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
	{ name => 'x0', type => 'float',
	  desc => 'The new x coordinate of the upper-left corner of the
		    scaled region' },
	{ name => 'y0', type => 'float',
	  desc => 'The new y coordinate of the upper-left corner of the
		    scaled region' },
	{ name => 'x1', type => 'float',
	  desc => 'The new x coordinate of the lower-right corner of the
		    scaled region' },
	{ name => 'y1', type => 'float',
	  desc => 'The new y coordinate of the lower-right corner of the
		    scaled region' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The scaled item' }
    );

    transform_invoke ("Scaling", <<CODE, 'x0 < x1 && y0 < y1');
      pika_matrix3_identity (&matrix);
      pika_transform_matrix_scale (&matrix,
                                   x, y, width, height,
                                   x0, y0, x1 - x0, y1 - y0);
CODE
}


sub item_transform_shear {
    $blurb = <<'BLURB';
Shear the specified item about its center by the specified magnitude.
BLURB

    $help = <<'HELP';
This procedure shears the specified item.


The shear type parameter indicates whether the shear will be applied
horizontally or vertically. The magnitude can be either positive or
negative and indicates the extent (in pixels) to shear by.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then sheared as specified.
The return value is the ID of the sheared floating selection.


If there is no selection or the item is not a drawable, the entire
item will be sheared according to the specified parameters.

The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_interpolation(), pika_context_set_transform_direction(),
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
        { name => 'shear_type',
	  type => 'enum PikaOrientationType (no PIKA_ORIENTATION_UNKNOWN)',
          desc => 'Type of shear' },
        { name => 'magnitude', type => 'float',
          desc => 'The magnitude of the shear' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The sheared item' }
    );

    transform_invoke ("Shearing", <<CODE);
      pika_matrix3_identity (&matrix);
      pika_transform_matrix_shear (&matrix,
                                   x, y, width, height,
                                   shear_type, magnitude);
CODE
}


sub item_transform_2d {
    $blurb = 'Transform the specified item in 2d.';

    $help = <<'HELP';
This procedure transforms the specified item.


The transformation is done by scaling by the x and y scale factors
about the point (source_x, source_y), then rotating around the same
point, then translating that point to the new position (dest_x,
dest_y).


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then transformed as specified.
The return value is the ID of the transformed floating selection.


If there is no selection or the item is not a drawable, the entire
item will be transformed according to the specified parameters.

The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_interpolation(), pika_context_set_transform_direction(),
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
        { name => 'source_x', type => 'float',
          desc => 'X coordinate of the transformation center' },
        { name => 'source_y', type => 'float',
          desc => 'Y coordinate of the transformation center' },
        { name => 'scale_x', type => 'float',
          desc => 'Amount to scale in x direction' },
        { name => 'scale_y', type => 'float',
          desc => 'Amount to scale in y direction' },
        { name => 'angle', type => 'float',
          desc => 'The angle of rotation (radians)' },
        { name => 'dest_x', type => 'float',
          desc => 'X coordinate of where the center goes' },
        { name => 'dest_y', type => 'float',
          desc => 'Y coordinate of where the center goes' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The transformed item' }
    );

    transform_invoke ("2D Transform", <<CODE);
      pika_matrix3_identity  (&matrix);
      pika_matrix3_translate (&matrix, -source_x, -source_y);
      pika_matrix3_scale     (&matrix, scale_x, scale_y);
      pika_matrix3_rotate    (&matrix, angle);
      pika_matrix3_translate (&matrix, dest_x, dest_y);
CODE
}


sub item_transform_matrix {
    $blurb = 'Transform the specified item in 2d.';

    $help = <<'HELP';
This procedure transforms the specified item.


The transformation is done by assembling a 3x3 matrix from the
coefficients passed.


If a selection exists and the item is a drawable, the portion of the
drawable which lies under the selection is cut from the drawable and
made into a floating selection which is then transformed as specified.
The return value is the ID of the transformed floating selection.


If there is no selection or the item is not a drawable, the entire
item will be transformed according to the specified matrix.

The return value will be equal to the item ID supplied as input.


This procedure is affected by the following context setters:
pika_context_set_interpolation(), pika_context_set_transform_direction(),
pika_context_set_transform_resize().
HELP

    &mitch_pdb_misc('2010', '2.8');

    @inargs = (
	{ name => 'item', type => 'item',
	  desc => 'The affected item' },
        { name => 'coeff_0_0', type => 'float',
          desc => 'coefficient (0,0) of the transformation matrix' },
        { name => 'coeff_0_1', type => 'float',
          desc => 'coefficient (0,1) of the transformation matrix' },
        { name => 'coeff_0_2', type => 'float',
          desc => 'coefficient (0,2) of the transformation matrix' },
        { name => 'coeff_1_0', type => 'float',
          desc => 'coefficient (1,0) of the transformation matrix' },
        { name => 'coeff_1_1', type => 'float',
          desc => 'coefficient (1,1) of the transformation matrix' },
        { name => 'coeff_1_2', type => 'float',
          desc => 'coefficient (1,2) of the transformation matrix' },
        { name => 'coeff_2_0', type => 'float',
          desc => 'coefficient (2,0) of the transformation matrix' },
        { name => 'coeff_2_1', type => 'float',
          desc => 'coefficient (2,1) of the transformation matrix' },
        { name => 'coeff_2_2', type => 'float',
          desc => 'coefficient (2,2) of the transformation matrix' }
    );

    @outargs = (
	{ name => 'item', type => 'item', no_declare => 1,
	  desc => 'The transformed item' }
    );

    transform_invoke ("2D Transforming", <<CODE);
      matrix.coeff[0][0] = coeff_0_0;
      matrix.coeff[0][1] = coeff_0_1;
      matrix.coeff[0][2] = coeff_0_2;
      matrix.coeff[1][0] = coeff_1_0;
      matrix.coeff[1][1] = coeff_1_1;
      matrix.coeff[1][2] = coeff_1_2;
      matrix.coeff[2][0] = coeff_2_0;
      matrix.coeff[2][1] = coeff_2_1;
      matrix.coeff[2][2] = coeff_2_2;
CODE
}


@headers = qw("libpikamath/pikamath.h"
              "core/pika-transform-utils.h"
              "core/pikachannel.h"
              "core/pikadrawable.h"
              "core/pikadrawable-transform.h"
              "core/pikaimage.h"
              "core/pikaprogress.h"
              "pikapdb-utils.h"
              "pikapdbcontext.h"
              "pika-intl.h");

@procs = qw(item_transform_translate
            item_transform_flip_simple
            item_transform_flip
            item_transform_perspective
            item_transform_rotate_simple
            item_transform_rotate
            item_transform_scale
            item_transform_shear
            item_transform_2d
            item_transform_matrix);

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

$desc = 'Transformation procedures';
$doc_title = 'pikaitemtransform';
$doc_short_desc = 'Functions to perform transformations on items.';
$doc_long_desc = 'Functions to perform transformations on items.';

1;