Adding upstream version 2.10.22.upstream/2.10.22upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 863 insertions, 0 deletions

diff --git a/app/core/gimpselection.c b/app/core/gimpselection.c
new file mode 100644
index 0000000..5f66b98
--- /dev/null
+++ b/app/core/gimpselection.c
@@ -0,0 +1,863 @@
+/* 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 <cairo.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+#include <gegl.h>
+
+#include "libgimpcolor/gimpcolor.h"
+
+#include "core-types.h"
+
+#include "gegl/gimp-babl.h"
+#include "gegl/gimp-gegl-apply-operation.h"
+#include "gegl/gimp-gegl-loops.h"
+
+#include "gimp.h"
+#include "gimpcontext.h"
+#include "gimpdrawable-edit.h"
+#include "gimpdrawable-private.h"
+#include "gimperror.h"
+#include "gimpimage.h"
+#include "gimpimage-undo.h"
+#include "gimpimage-undo-push.h"
+#include "gimplayer.h"
+#include "gimplayer-new.h"
+#include "gimplayermask.h"
+#include "gimplayer-floating-selection.h"
+#include "gimppickable.h"
+#include "gimpselection.h"
+
+#include "gimp-intl.h"
+
+
+static gboolean   gimp_selection_is_attached   (GimpItem            *item);
+static GimpItemTree * gimp_selection_get_tree  (GimpItem            *item);
+static void       gimp_selection_translate     (GimpItem            *item,
+                                                gdouble              offset_x,
+                                                gdouble              offset_y,
+                                                gboolean             push_undo);
+static void       gimp_selection_scale         (GimpItem            *item,
+                                                gint                 new_width,
+                                                gint                 new_height,
+                                                gint                 new_offset_x,
+                                                gint                 new_offset_y,
+                                                GimpInterpolationType interp_type,
+                                                GimpProgress        *progress);
+static void       gimp_selection_resize        (GimpItem            *item,
+                                                GimpContext         *context,
+                                                GimpFillType         fill_type,
+                                                gint                 new_width,
+                                                gint                 new_height,
+                                                gint                 offset_x,
+                                                gint                 offset_y);
+static void       gimp_selection_flip          (GimpItem            *item,
+                                                GimpContext         *context,
+                                                GimpOrientationType  flip_type,
+                                                gdouble              axis,
+                                                gboolean             clip_result);
+static void       gimp_selection_rotate        (GimpItem            *item,
+                                                GimpContext         *context,
+                                                GimpRotationType     rotation_type,
+                                                gdouble              center_x,
+                                                gdouble              center_y,
+                                                gboolean             clip_result);
+static gboolean   gimp_selection_fill          (GimpItem            *item,
+                                                GimpDrawable        *drawable,
+                                                GimpFillOptions     *fill_options,
+                                                gboolean             push_undo,
+                                                GimpProgress        *progress,
+                                                GError             **error);
+static gboolean   gimp_selection_stroke        (GimpItem            *item,
+                                                GimpDrawable        *drawable,
+                                                GimpStrokeOptions   *stroke_options,
+                                                gboolean             push_undo,
+                                                GimpProgress        *progress,
+                                                GError             **error);
+static void       gimp_selection_convert_type  (GimpDrawable        *drawable,
+                                                GimpImage           *dest_image,
+                                                const Babl          *new_format,
+                                                GimpColorProfile    *dest_profile,
+                                                GeglDitherMethod     layer_dither_type,
+                                                GeglDitherMethod     mask_dither_type,
+                                                gboolean             push_undo,
+                                                GimpProgress        *progress);
+static void gimp_selection_invalidate_boundary (GimpDrawable        *drawable);
+
+static gboolean   gimp_selection_boundary      (GimpChannel         *channel,
+                                                const GimpBoundSeg **segs_in,
+                                                const GimpBoundSeg **segs_out,
+                                                gint                *num_segs_in,
+                                                gint                *num_segs_out,
+                                                gint                 x1,
+                                                gint                 y1,
+                                                gint                 x2,
+                                                gint                 y2);
+static gboolean   gimp_selection_is_empty      (GimpChannel         *channel);
+static void       gimp_selection_feather       (GimpChannel         *channel,
+                                                gdouble              radius_x,
+                                                gdouble              radius_y,
+                                                gboolean             edge_lock,
+                                                gboolean             push_undo);
+static void       gimp_selection_sharpen       (GimpChannel         *channel,
+                                                gboolean             push_undo);
+static void       gimp_selection_clear         (GimpChannel         *channel,
+                                                const gchar         *undo_desc,
+                                                gboolean             push_undo);
+static void       gimp_selection_all           (GimpChannel         *channel,
+                                                gboolean             push_undo);
+static void       gimp_selection_invert        (GimpChannel         *channel,
+                                                gboolean             push_undo);
+static void       gimp_selection_border        (GimpChannel         *channel,
+                                                gint                 radius_x,
+                                                gint                 radius_y,
+                                                GimpChannelBorderStyle style,
+                                                gboolean             edge_lock,
+                                                gboolean             push_undo);
+static void       gimp_selection_grow          (GimpChannel         *channel,
+                                                gint                 radius_x,
+                                                gint                 radius_y,
+                                                gboolean             push_undo);
+static void       gimp_selection_shrink        (GimpChannel         *channel,
+                                                gint                 radius_x,
+                                                gint                 radius_y,
+                                                gboolean             edge_lock,
+                                                gboolean             push_undo);
+static void       gimp_selection_flood         (GimpChannel         *channel,
+                                                gboolean             push_undo);
+
+
+G_DEFINE_TYPE (GimpSelection, gimp_selection, GIMP_TYPE_CHANNEL)
+
+#define parent_class gimp_selection_parent_class
+
+
+static void
+gimp_selection_class_init (GimpSelectionClass *klass)
+{
+  GimpViewableClass *viewable_class = GIMP_VIEWABLE_CLASS (klass);
+  GimpItemClass     *item_class     = GIMP_ITEM_CLASS (klass);
+  GimpDrawableClass *drawable_class = GIMP_DRAWABLE_CLASS (klass);
+  GimpChannelClass  *channel_class  = GIMP_CHANNEL_CLASS (klass);
+
+  viewable_class->default_icon_name   = "gimp-selection";
+
+  item_class->is_attached             = gimp_selection_is_attached;
+  item_class->get_tree                = gimp_selection_get_tree;
+  item_class->translate               = gimp_selection_translate;
+  item_class->scale                   = gimp_selection_scale;
+  item_class->resize                  = gimp_selection_resize;
+  item_class->flip                    = gimp_selection_flip;
+  item_class->rotate                  = gimp_selection_rotate;
+  item_class->fill                    = gimp_selection_fill;
+  item_class->stroke                  = gimp_selection_stroke;
+  item_class->default_name            = _("Selection Mask");
+  item_class->translate_desc          = C_("undo-type", "Move Selection");
+  item_class->fill_desc               = C_("undo-type", "Fill Selection");
+  item_class->stroke_desc             = C_("undo-type", "Stroke Selection");
+
+  drawable_class->convert_type        = gimp_selection_convert_type;
+  drawable_class->invalidate_boundary = gimp_selection_invalidate_boundary;
+
+  channel_class->boundary             = gimp_selection_boundary;
+  channel_class->is_empty             = gimp_selection_is_empty;
+  channel_class->feather              = gimp_selection_feather;
+  channel_class->sharpen              = gimp_selection_sharpen;
+  channel_class->clear                = gimp_selection_clear;
+  channel_class->all                  = gimp_selection_all;
+  channel_class->invert               = gimp_selection_invert;
+  channel_class->border               = gimp_selection_border;
+  channel_class->grow                 = gimp_selection_grow;
+  channel_class->shrink               = gimp_selection_shrink;
+  channel_class->flood                = gimp_selection_flood;
+
+  channel_class->feather_desc         = C_("undo-type", "Feather Selection");
+  channel_class->sharpen_desc         = C_("undo-type", "Sharpen Selection");
+  channel_class->clear_desc           = C_("undo-type", "Select None");
+  channel_class->all_desc             = C_("undo-type", "Select All");
+  channel_class->invert_desc          = C_("undo-type", "Invert Selection");
+  channel_class->border_desc          = C_("undo-type", "Border Selection");
+  channel_class->grow_desc            = C_("undo-type", "Grow Selection");
+  channel_class->shrink_desc          = C_("undo-type", "Shrink Selection");
+  channel_class->flood_desc           = C_("undo-type", "Remove Holes");
+}
+
+static void
+gimp_selection_init (GimpSelection *selection)
+{
+}
+
+static gboolean
+gimp_selection_is_attached (GimpItem *item)
+{
+  return (GIMP_IS_IMAGE (gimp_item_get_image (item)) &&
+          gimp_image_get_mask (gimp_item_get_image (item)) ==
+          GIMP_CHANNEL (item));
+}
+
+static GimpItemTree *
+gimp_selection_get_tree (GimpItem *item)
+{
+  return NULL;
+}
+
+static void
+gimp_selection_translate (GimpItem *item,
+                          gdouble   offset_x,
+                          gdouble   offset_y,
+                          gboolean  push_undo)
+{
+  GIMP_ITEM_CLASS (parent_class)->translate (item, offset_x, offset_y,
+                                             push_undo);
+}
+
+static void
+gimp_selection_scale (GimpItem              *item,
+                      gint                   new_width,
+                      gint                   new_height,
+                      gint                   new_offset_x,
+                      gint                   new_offset_y,
+                      GimpInterpolationType  interp_type,
+                      GimpProgress          *progress)
+{
+  GIMP_ITEM_CLASS (parent_class)->scale (item, new_width, new_height,
+                                         new_offset_x, new_offset_y,
+                                         interp_type, progress);
+
+  gimp_item_set_offset (item, 0, 0);
+}
+
+static void
+gimp_selection_resize (GimpItem     *item,
+                       GimpContext  *context,
+                       GimpFillType  fill_type,
+                       gint          new_width,
+                       gint          new_height,
+                       gint          offset_x,
+                       gint          offset_y)
+{
+  GIMP_ITEM_CLASS (parent_class)->resize (item, context, GIMP_FILL_TRANSPARENT,
+                                          new_width, new_height,
+                                          offset_x, offset_y);
+
+  gimp_item_set_offset (item, 0, 0);
+}
+
+static void
+gimp_selection_flip (GimpItem            *item,
+                     GimpContext         *context,
+                     GimpOrientationType  flip_type,
+                     gdouble              axis,
+                     gboolean             clip_result)
+{
+  GIMP_ITEM_CLASS (parent_class)->flip (item, context, flip_type, axis, TRUE);
+}
+
+static void
+gimp_selection_rotate (GimpItem         *item,
+                       GimpContext      *context,
+                       GimpRotationType  rotation_type,
+                       gdouble           center_x,
+                       gdouble           center_y,
+                       gboolean          clip_result)
+{
+  GIMP_ITEM_CLASS (parent_class)->rotate (item, context, rotation_type,
+                                          center_x, center_y,
+                                          clip_result);
+}
+
+static gboolean
+gimp_selection_fill (GimpItem         *item,
+                     GimpDrawable     *drawable,
+                     GimpFillOptions  *fill_options,
+                     gboolean          push_undo,
+                     GimpProgress     *progress,
+                     GError          **error)
+{
+  GimpSelection      *selection = GIMP_SELECTION (item);
+  const GimpBoundSeg *dummy_in;
+  const GimpBoundSeg *dummy_out;
+  gint                num_dummy_in;
+  gint                num_dummy_out;
+  gboolean            retval;
+
+  if (! gimp_channel_boundary (GIMP_CHANNEL (selection),
+                               &dummy_in, &dummy_out,
+                               &num_dummy_in, &num_dummy_out,
+                               0, 0, 0, 0))
+    {
+      g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
+                           _("There is no selection to fill."));
+      return FALSE;
+    }
+
+  gimp_selection_suspend (selection);
+
+  retval = GIMP_ITEM_CLASS (parent_class)->fill (item, drawable,
+                                                 fill_options,
+                                                 push_undo, progress, error);
+
+  gimp_selection_resume (selection);
+
+  return retval;
+}
+
+static gboolean
+gimp_selection_stroke (GimpItem           *item,
+                       GimpDrawable       *drawable,
+                       GimpStrokeOptions  *stroke_options,
+                       gboolean            push_undo,
+                       GimpProgress       *progress,
+                       GError            **error)
+{
+  GimpSelection      *selection = GIMP_SELECTION (item);
+  const GimpBoundSeg *dummy_in;
+  const GimpBoundSeg *dummy_out;
+  gint                num_dummy_in;
+  gint                num_dummy_out;
+  gboolean            retval;
+
+  if (! gimp_channel_boundary (GIMP_CHANNEL (selection),
+                               &dummy_in, &dummy_out,
+                               &num_dummy_in, &num_dummy_out,
+                               0, 0, 0, 0))
+    {
+      g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
+                           _("There is no selection to stroke."));
+      return FALSE;
+    }
+
+  gimp_selection_suspend (selection);
+
+  retval = GIMP_ITEM_CLASS (parent_class)->stroke (item, drawable,
+                                                   stroke_options,
+                                                   push_undo, progress, error);
+
+  gimp_selection_resume (selection);
+
+  return retval;
+}
+
+static void
+gimp_selection_convert_type (GimpDrawable      *drawable,
+                             GimpImage         *dest_image,
+                             const Babl        *new_format,
+                             GimpColorProfile  *dest_profile,
+                             GeglDitherMethod   layer_dither_type,
+                             GeglDitherMethod   mask_dither_type,
+                             gboolean           push_undo,
+                             GimpProgress      *progress)
+{
+  new_format =
+    gimp_babl_mask_format (gimp_babl_format_get_precision (new_format));
+
+  GIMP_DRAWABLE_CLASS (parent_class)->convert_type (drawable, dest_image,
+                                                    new_format,
+                                                    dest_profile,
+                                                    layer_dither_type,
+                                                    mask_dither_type,
+                                                    push_undo,
+                                                    progress);
+}
+
+static void
+gimp_selection_invalidate_boundary (GimpDrawable *drawable)
+{
+  GimpImage *image = gimp_item_get_image (GIMP_ITEM (drawable));
+  GimpLayer *layer;
+
+  /*  Turn the current selection off  */
+  gimp_image_selection_invalidate (image);
+
+  GIMP_DRAWABLE_CLASS (parent_class)->invalidate_boundary (drawable);
+
+  /*  If there is a floating selection, update it's area...
+   *  we need to do this since this selection mask can act as an additional
+   *  mask in the composition of the floating selection
+   */
+  layer = gimp_image_get_active_layer (image);
+
+  if (layer && gimp_layer_is_floating_sel (layer))
+    {
+      gimp_drawable_update (GIMP_DRAWABLE (layer), 0, 0, -1, -1);
+    }
+
+#if 0
+  /*  invalidate the preview  */
+  drawable->private->preview_valid = FALSE;
+#endif
+}
+
+static gboolean
+gimp_selection_boundary (GimpChannel         *channel,
+                         const GimpBoundSeg **segs_in,
+                         const GimpBoundSeg **segs_out,
+                         gint                *num_segs_in,
+                         gint                *num_segs_out,
+                         gint                 unused1,
+                         gint                 unused2,
+                         gint                 unused3,
+                         gint                 unused4)
+{
+  GimpImage    *image = gimp_item_get_image (GIMP_ITEM (channel));
+  GimpDrawable *drawable;
+  GimpLayer    *layer;
+
+  if ((layer = gimp_image_get_floating_selection (image)))
+    {
+      /*  If there is a floating selection, then
+       *  we need to do some slightly different boundaries.
+       *  Instead of inside and outside boundaries being defined
+       *  by the extents of the layer, the inside boundary (the one
+       *  that actually marches and is black/white) is the boundary of
+       *  the floating selection.  The outside boundary (doesn't move,
+       *  is black/gray) is defined as the normal selection mask
+       */
+
+      /*  Find the selection mask boundary  */
+      GIMP_CHANNEL_CLASS (parent_class)->boundary (channel,
+                                                   segs_in, segs_out,
+                                                   num_segs_in, num_segs_out,
+                                                   0, 0, 0, 0);
+
+      /*  Find the floating selection boundary  */
+      *segs_in = floating_sel_boundary (layer, num_segs_in);
+
+      return TRUE;
+    }
+  else if ((drawable = gimp_image_get_active_drawable (image)) &&
+           GIMP_IS_CHANNEL (drawable))
+    {
+      /*  Otherwise, return the boundary...if a channel is active  */
+
+      return GIMP_CHANNEL_CLASS (parent_class)->boundary (channel,
+                                                          segs_in, segs_out,
+                                                          num_segs_in,
+                                                          num_segs_out,
+                                                          0, 0,
+                                                          gimp_image_get_width  (image),
+                                                          gimp_image_get_height (image));
+    }
+  else if ((layer = gimp_image_get_active_layer (image)))
+    {
+      /*  If a layer is active, we return multiple boundaries based
+       *  on the extents
+       */
+
+      gint x1, y1;
+      gint x2, y2;
+      gint offset_x;
+      gint offset_y;
+
+      gimp_item_get_offset (GIMP_ITEM (layer), &offset_x, &offset_y);
+
+      x1 = CLAMP (offset_x, 0, gimp_image_get_width  (image));
+      y1 = CLAMP (offset_y, 0, gimp_image_get_height (image));
+      x2 = CLAMP (offset_x + gimp_item_get_width (GIMP_ITEM (layer)),
+                  0, gimp_image_get_width (image));
+      y2 = CLAMP (offset_y + gimp_item_get_height (GIMP_ITEM (layer)),
+                  0, gimp_image_get_height (image));
+
+      return GIMP_CHANNEL_CLASS (parent_class)->boundary (channel,
+                                                          segs_in, segs_out,
+                                                          num_segs_in,
+                                                          num_segs_out,
+                                                          x1, y1, x2, y2);
+    }
+
+  *segs_in      = NULL;
+  *segs_out     = NULL;
+  *num_segs_in  = 0;
+  *num_segs_out = 0;
+
+  return FALSE;
+}
+
+static gboolean
+gimp_selection_is_empty (GimpChannel *channel)
+{
+  GimpSelection *selection = GIMP_SELECTION (channel);
+
+  /*  in order to allow stroking of selections, we need to pretend here
+   *  that the selection mask is empty so that it doesn't mask the paint
+   *  during the stroke operation.
+   */
+  if (selection->suspend_count > 0)
+    return TRUE;
+
+  return GIMP_CHANNEL_CLASS (parent_class)->is_empty (channel);
+}
+
+static void
+gimp_selection_feather (GimpChannel *channel,
+                        gdouble      radius_x,
+                        gdouble      radius_y,
+                        gboolean     edge_lock,
+                        gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->feather (channel, radius_x, radius_y,
+                                              edge_lock, push_undo);
+}
+
+static void
+gimp_selection_sharpen (GimpChannel *channel,
+                        gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->sharpen (channel, push_undo);
+}
+
+static void
+gimp_selection_clear (GimpChannel *channel,
+                      const gchar *undo_desc,
+                      gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->clear (channel, undo_desc, push_undo);
+}
+
+static void
+gimp_selection_all (GimpChannel *channel,
+                    gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->all (channel, push_undo);
+}
+
+static void
+gimp_selection_invert (GimpChannel *channel,
+                       gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->invert (channel, push_undo);
+}
+
+static void
+gimp_selection_border (GimpChannel            *channel,
+                       gint                    radius_x,
+                       gint                    radius_y,
+                       GimpChannelBorderStyle  style,
+                       gboolean                edge_lock,
+                       gboolean                push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->border (channel,
+                                             radius_x, radius_y,
+                                             style, edge_lock,
+                                             push_undo);
+}
+
+static void
+gimp_selection_grow (GimpChannel *channel,
+                     gint         radius_x,
+                     gint         radius_y,
+                     gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->grow (channel,
+                                           radius_x, radius_y,
+                                           push_undo);
+}
+
+static void
+gimp_selection_shrink (GimpChannel *channel,
+                       gint         radius_x,
+                       gint         radius_y,
+                       gboolean     edge_lock,
+                       gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->shrink (channel,
+                                             radius_x, radius_y, edge_lock,
+                                             push_undo);
+}
+
+static void
+gimp_selection_flood (GimpChannel *channel,
+                      gboolean     push_undo)
+{
+  GIMP_CHANNEL_CLASS (parent_class)->flood (channel, push_undo);
+}
+
+
+/*  public functions  */
+
+GimpChannel *
+gimp_selection_new (GimpImage *image,
+                    gint       width,
+                    gint       height)
+{
+  GimpRGB      black = { 0.0, 0.0, 0.0, 0.5 };
+  GimpChannel *channel;
+
+  g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
+  g_return_val_if_fail (width > 0 && height > 0, NULL);
+
+  channel = GIMP_CHANNEL (gimp_drawable_new (GIMP_TYPE_SELECTION,
+                                             image, NULL,
+                                             0, 0, width, height,
+                                             gimp_image_get_mask_format (image)));
+
+  gimp_channel_set_color (channel, &black, FALSE);
+  gimp_channel_set_show_masked (channel, TRUE);
+
+  channel->x2 = width;
+  channel->y2 = height;
+
+  return channel;
+}
+
+gint
+gimp_selection_suspend (GimpSelection *selection)
+{
+  g_return_val_if_fail (GIMP_IS_SELECTION (selection), 0);
+
+  selection->suspend_count++;
+
+  return selection->suspend_count;
+}
+
+gint
+gimp_selection_resume (GimpSelection *selection)
+{
+  g_return_val_if_fail (GIMP_IS_SELECTION (selection), 0);
+  g_return_val_if_fail (selection->suspend_count > 0, 0);
+
+  selection->suspend_count--;
+
+  return selection->suspend_count;
+}
+
+GeglBuffer *
+gimp_selection_extract (GimpSelection *selection,
+                        GimpPickable  *pickable,
+                        GimpContext   *context,
+                        gboolean       cut_image,
+                        gboolean       keep_indexed,
+                        gboolean       add_alpha,
+                        gint          *offset_x,
+                        gint          *offset_y,
+                        GError       **error)
+{
+  GimpImage  *image;
+  GeglBuffer *src_buffer;
+  GeglBuffer *dest_buffer;
+  const Babl *src_format;
+  const Babl *dest_format;
+  gint        x1, y1, x2, y2;
+  gboolean    non_empty;
+  gint        off_x, off_y;
+
+  g_return_val_if_fail (GIMP_IS_SELECTION (selection), NULL);
+  g_return_val_if_fail (GIMP_IS_PICKABLE (pickable), NULL);
+  if (GIMP_IS_ITEM (pickable))
+    g_return_val_if_fail (gimp_item_is_attached (GIMP_ITEM (pickable)), NULL);
+  g_return_val_if_fail (GIMP_IS_CONTEXT (context), NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+  image = gimp_pickable_get_image (pickable);
+
+  /*  If there are no bounds, then just extract the entire image
+   *  This may not be the correct behavior, but after getting rid
+   *  of floating selections, it's still tempting to "cut" or "copy"
+   *  a small layer and expect it to work, even though there is no
+   *  actual selection mask
+   */
+  if (GIMP_IS_DRAWABLE (pickable))
+    {
+      non_empty = gimp_item_mask_bounds (GIMP_ITEM (pickable),
+                                         &x1, &y1, &x2, &y2);
+
+      gimp_item_get_offset (GIMP_ITEM (pickable), &off_x, &off_y);
+    }
+  else
+    {
+      non_empty = gimp_item_bounds (GIMP_ITEM (selection),
+                                    &x1, &y1, &x2, &y2);
+      x2 += x1;
+      y2 += y1;
+
+      off_x = 0;
+      off_y = 0;
+
+      /* can't cut from non-drawables, fall back to copy */
+      cut_image = FALSE;
+    }
+
+  if (non_empty && ((x1 == x2) || (y1 == y2)))
+    {
+      g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
+                           _("Unable to cut or copy because the "
+                             "selected region is empty."));
+      return NULL;
+    }
+
+  /*  If there is a selection, we must add alpha because the selection
+   *  could have any shape.
+   */
+  if (non_empty)
+    add_alpha = TRUE;
+
+  src_format = gimp_pickable_get_format (pickable);
+
+  /*  How many bytes in the temp buffer?  */
+  if (babl_format_is_palette (src_format) && ! keep_indexed)
+    {
+      dest_format = gimp_image_get_format (image, GIMP_RGB,
+                                           gimp_image_get_precision (image),
+                                           add_alpha ||
+                                           babl_format_has_alpha (src_format));
+    }
+  else
+    {
+      if (add_alpha)
+        dest_format = gimp_pickable_get_format_with_alpha (pickable);
+      else
+        dest_format = src_format;
+    }
+
+  gimp_pickable_flush (pickable);
+
+  src_buffer = gimp_pickable_get_buffer (pickable);
+
+  /*  Allocate the temp buffer  */
+  dest_buffer = gegl_buffer_new (GEGL_RECTANGLE (0, 0, x2 - x1, y2 - y1),
+                                 dest_format);
+
+  /*  First, copy the pixels, possibly doing INDEXED->RGB and adding alpha  */
+  gimp_gegl_buffer_copy (src_buffer,  GEGL_RECTANGLE (x1, y1, x2 - x1, y2 - y1),
+                         GEGL_ABYSS_NONE,
+                         dest_buffer, GEGL_RECTANGLE (0, 0, 0, 0));
+
+  if (non_empty)
+    {
+      /*  If there is a selection, mask the dest_buffer with it  */
+
+      GeglBuffer *mask_buffer;
+
+      mask_buffer = gimp_drawable_get_buffer (GIMP_DRAWABLE (selection));
+
+      gimp_gegl_apply_opacity (dest_buffer, NULL, NULL, dest_buffer,
+                               mask_buffer,
+                               - (off_x + x1),
+                               - (off_y + y1),
+                               1.0);
+
+      if (cut_image)
+        {
+          gimp_drawable_edit_clear (GIMP_DRAWABLE (pickable), context);
+        }
+    }
+  else if (cut_image)
+    {
+      /*  If we're cutting without selection, remove either the layer
+       *  (or floating selection), the layer mask, or the channel
+       */
+      if (GIMP_IS_LAYER (pickable))
+        {
+          gimp_image_remove_layer (image, GIMP_LAYER (pickable),
+                                   TRUE, NULL);
+        }
+      else if (GIMP_IS_LAYER_MASK (pickable))
+        {
+          gimp_layer_apply_mask (gimp_layer_mask_get_layer (GIMP_LAYER_MASK (pickable)),
+                                 GIMP_MASK_DISCARD, TRUE);
+        }
+      else if (GIMP_IS_CHANNEL (pickable))
+        {
+          gimp_image_remove_channel (image, GIMP_CHANNEL (pickable),
+                                     TRUE, NULL);
+        }
+    }
+
+  *offset_x = x1 + off_x;
+  *offset_y = y1 + off_y;
+
+  return dest_buffer;
+}
+
+GimpLayer *
+gimp_selection_float (GimpSelection *selection,
+                      GimpDrawable  *drawable,
+                      GimpContext   *context,
+                      gboolean       cut_image,
+                      gint           off_x,
+                      gint           off_y,
+                      GError       **error)
+{
+  GimpImage        *image;
+  GimpLayer        *layer;
+  GeglBuffer       *buffer;
+  GimpColorProfile *profile;
+  gint              x1, y1;
+  gint              x2, y2;
+
+  g_return_val_if_fail (GIMP_IS_SELECTION (selection), NULL);
+  g_return_val_if_fail (GIMP_IS_DRAWABLE (drawable), NULL);
+  g_return_val_if_fail (gimp_item_is_attached (GIMP_ITEM (drawable)), NULL);
+  g_return_val_if_fail (GIMP_IS_CONTEXT (context), NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+  image = gimp_item_get_image (GIMP_ITEM (selection));
+
+  /*  Make sure there is a region to float...  */
+  if (! gimp_item_mask_bounds (GIMP_ITEM (drawable), &x1, &y1, &x2, &y2) ||
+      (x1 == x2 || y1 == y2))
+    {
+      g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
+                           _("Cannot float selection because the selected "
+                             "region is empty."));
+      return NULL;
+    }
+
+  /*  Start an undo group  */
+  gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_FS_FLOAT,
+                               C_("undo-type", "Float Selection"));
+
+  /*  Cut or copy the selected region  */
+  buffer = gimp_selection_extract (selection, GIMP_PICKABLE (drawable), context,
+                                   cut_image, FALSE, TRUE,
+                                   &x1, &y1, NULL);
+
+  profile = gimp_color_managed_get_color_profile (GIMP_COLOR_MANAGED (drawable));
+
+  /*  Clear the selection  */
+  gimp_channel_clear (GIMP_CHANNEL (selection), NULL, TRUE);
+
+  /* Create a new layer from the buffer, using the drawable's type
+   *  because it may be different from the image's type if we cut from
+   *  a channel or layer mask
+   */
+  layer = gimp_layer_new_from_gegl_buffer (buffer, image,
+                                           gimp_drawable_get_format_with_alpha (drawable),
+                                           _("Floated Layer"),
+                                           GIMP_OPACITY_OPAQUE,
+                                           gimp_image_get_default_new_layer_mode (image),
+                                           profile);
+
+  /*  Set the offsets  */
+  gimp_item_set_offset (GIMP_ITEM (layer), x1 + off_x, y1 + off_y);
+
+  /*  Free the temp buffer  */
+  g_object_unref (buffer);
+
+  /*  Add the floating layer to the image  */
+  floating_sel_attach (layer, drawable);
+
+  /*  End an undo group  */
+  gimp_image_undo_group_end (image);
+
+  /*  invalidate the image's boundary variables  */
+  GIMP_CHANNEL (selection)->boundary_known = FALSE;
+
+  return layer;
+}