Adding upstream version 2.10.34.upstream/2.10.34upstream

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

1 files changed, 1157 insertions, 0 deletions

diff --git a/libgimp/gimpexport.c b/libgimp/gimpexport.c
new file mode 100644
index 0000000..e5621da
--- /dev/null
+++ b/libgimp/gimpexport.c
@@ -0,0 +1,1157 @@
+/* LIBGIMP - The GIMP Library
+ * Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
+ *
+ * gimpexport.c
+ * Copyright (C) 1999-2004 Sven Neumann <sven@gimp.org>
+ *
+ * This library is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <string.h>
+
+#include <gtk/gtk.h>
+
+#include "gimp.h"
+#include "gimpui.h"
+
+#include "libgimp-intl.h"
+
+
+/**
+ * SECTION: gimpexport
+ * @title: gimpexport
+ * @short_description: Export an image before it is saved.
+ *
+ * This function should be called by all save_plugins unless they are
+ * able to save all image formats GIMP knows about. It takes care of
+ * asking the user if she wishes to export the image to a format the
+ * save_plugin can handle. It then performs the necessary conversions
+ * (e.g. Flatten) on a copy of the image so that the image can be
+ * saved without changing the original image.
+ *
+ * The capabilities of the save_plugin are specified by combining
+ * #GimpExportCapabilities using a bitwise OR.
+ *
+ * Make sure you have initialized GTK+ before you call this function
+ * as it will most probably have to open a dialog.
+ **/
+
+
+typedef void (* ExportFunc) (gint32  imageID,
+                             gint32 *drawable_ID);
+
+
+/* the export action structure */
+typedef struct
+{
+  ExportFunc   default_action;
+  ExportFunc   alt_action;
+  const gchar *reason;
+  const gchar *possibilities[2];
+  gint         choice;
+} ExportAction;
+
+
+/* the functions that do the actual export */
+
+static void
+export_merge (gint32  image_ID,
+              gint32 *drawable_ID)
+{
+  gint32  nlayers;
+  gint32  nvisible = 0;
+  gint32  i;
+  gint32 *layers;
+  gint32  merged;
+  gint32  transp;
+
+  layers = gimp_image_get_layers (image_ID, &nlayers);
+  for (i = 0; i < nlayers; i++)
+    {
+      if (gimp_item_get_visible (layers[i]))
+        nvisible++;
+    }
+
+  if (nvisible <= 1)
+    {
+      /* if there is only one (or zero) visible layer, add a new
+       * transparent layer that has the same size as the canvas.  The
+       * merge that follows will ensure that the offset, opacity and
+       * size are correct
+       */
+      transp = gimp_layer_new (image_ID, "-",
+                               gimp_image_width (image_ID),
+                               gimp_image_height (image_ID),
+                               gimp_drawable_type (*drawable_ID) | 1,
+                               100.0, GIMP_LAYER_MODE_NORMAL);
+      gimp_image_insert_layer (image_ID, transp, -1, 1);
+      gimp_selection_none (image_ID);
+      gimp_drawable_edit_clear (transp);
+      nvisible++;
+    }
+
+  if (nvisible > 1)
+    {
+      g_free (layers);
+      merged = gimp_image_merge_visible_layers (image_ID, GIMP_CLIP_TO_IMAGE);
+
+      if (merged != -1)
+        *drawable_ID = merged;
+      else
+        return;  /* shouldn't happen */
+
+      layers = gimp_image_get_layers (image_ID, &nlayers);
+
+      /*  make sure that the merged drawable matches the image size  */
+      if (gimp_drawable_width  (merged) != gimp_image_width  (image_ID) ||
+          gimp_drawable_height (merged) != gimp_image_height (image_ID))
+        {
+          gint off_x, off_y;
+
+          gimp_drawable_offsets (merged, &off_x, &off_y);
+          gimp_layer_resize (merged,
+                             gimp_image_width (image_ID),
+                             gimp_image_height (image_ID),
+                             off_x, off_y);
+        }
+    }
+
+  /* remove any remaining (invisible) layers */
+  for (i = 0; i < nlayers; i++)
+    {
+      if (layers[i] != *drawable_ID)
+        gimp_image_remove_layer (image_ID, layers[i]);
+    }
+  g_free (layers);
+}
+
+static void
+export_flatten (gint32  image_ID,
+                gint32 *drawable_ID)
+{
+  gint32 flattened;
+
+  flattened = gimp_image_flatten (image_ID);
+
+  if (flattened != -1)
+    *drawable_ID = flattened;
+}
+
+static void
+export_remove_alpha (gint32  image_ID,
+                     gint32 *drawable_ID)
+{
+  gint32  n_layers;
+  gint32 *layers;
+  gint    i;
+
+  layers = gimp_image_get_layers (image_ID, &n_layers);
+
+  for (i = 0; i < n_layers; i++)
+    {
+      if (gimp_drawable_has_alpha (layers[i]))
+        gimp_layer_flatten (layers[i]);
+    }
+
+  g_free (layers);
+}
+
+static void
+export_apply_masks (gint32  image_ID,
+                    gint   *drawable_ID)
+{
+  gint32  n_layers;
+  gint32 *layers;
+  gint    i;
+
+  layers = gimp_image_get_layers (image_ID, &n_layers);
+
+  for (i = 0; i < n_layers; i++)
+    {
+      if (gimp_layer_get_mask (layers[i]) != -1)
+        {
+          /* we can't apply the mask directly to a layer group, so merge it
+           * first
+           */
+          if (gimp_item_is_group (layers[i]))
+            layers[i] = gimp_image_merge_layer_group (image_ID, layers[i]);
+
+          gimp_layer_remove_mask (layers[i], GIMP_MASK_APPLY);
+        }
+    }
+
+  g_free (layers);
+}
+
+static void
+export_convert_rgb (gint32  image_ID,
+                    gint32 *drawable_ID)
+{
+  gimp_image_convert_rgb (image_ID);
+}
+
+static void
+export_convert_grayscale (gint32  image_ID,
+                          gint32 *drawable_ID)
+{
+  gimp_image_convert_grayscale (image_ID);
+}
+
+static void
+export_convert_indexed (gint32  image_ID,
+                        gint32 *drawable_ID)
+{
+  gint32 nlayers;
+
+  /* check alpha */
+  g_free (gimp_image_get_layers (image_ID, &nlayers));
+  if (nlayers > 1 || gimp_drawable_has_alpha (*drawable_ID))
+    gimp_image_convert_indexed (image_ID,
+                                GIMP_CONVERT_DITHER_NONE,
+                                GIMP_CONVERT_PALETTE_GENERATE,
+                                255, FALSE, FALSE, "");
+  else
+    gimp_image_convert_indexed (image_ID,
+                                GIMP_CONVERT_DITHER_NONE,
+                                GIMP_CONVERT_PALETTE_GENERATE,
+                                256, FALSE, FALSE, "");
+}
+
+static void
+export_convert_bitmap (gint32  image_ID,
+                       gint32 *drawable_ID)
+{
+  if (gimp_image_base_type (image_ID) == GIMP_INDEXED)
+    gimp_image_convert_rgb (image_ID);
+
+  gimp_image_convert_indexed (image_ID,
+                              GIMP_CONVERT_DITHER_FS,
+                              GIMP_CONVERT_PALETTE_GENERATE,
+                              2, FALSE, FALSE, "");
+}
+
+static void
+export_add_alpha (gint32  image_ID,
+                  gint32 *drawable_ID)
+{
+  gint32  nlayers;
+  gint32  i;
+  gint32 *layers;
+
+  layers = gimp_image_get_layers (image_ID, &nlayers);
+  for (i = 0; i < nlayers; i++)
+    {
+      if (!gimp_drawable_has_alpha (layers[i]))
+        gimp_layer_add_alpha (layers[i]);
+    }
+  g_free (layers);
+}
+
+static void
+export_crop_image (gint32  image_ID,
+                   gint32 *drawable_ID)
+{
+  gimp_image_crop (image_ID,
+                   gimp_image_width  (image_ID),
+                   gimp_image_height (image_ID),
+                   0, 0);
+}
+
+static void
+export_resize_image (gint32  image_ID,
+                     gint32 *drawable_ID)
+{
+  gimp_image_resize_to_layers (image_ID);
+}
+
+static void
+export_void (gint32  image_ID,
+             gint32 *drawable_ID)
+{
+  /* do nothing */
+}
+
+
+/* a set of predefined actions */
+
+static ExportAction export_action_merge =
+{
+  export_merge,
+  NULL,
+  N_("%s plug-in can't handle layers"),
+  { N_("Merge Visible Layers"), NULL },
+  0
+};
+
+static ExportAction export_action_merge_single =
+{
+  export_merge,
+  NULL,
+  N_("%s plug-in can't handle layer offsets, size or opacity"),
+  { N_("Merge Visible Layers"), NULL },
+  0
+};
+
+static ExportAction export_action_animate_or_merge =
+{
+  NULL,
+  export_merge,
+  N_("%s plug-in can only handle layers as animation frames"),
+  { N_("Save as Animation"), N_("Merge Visible Layers") },
+  0
+};
+
+static ExportAction export_action_animate_or_flatten =
+{
+  NULL,
+  export_flatten,
+  N_("%s plug-in can only handle layers as animation frames"),
+  { N_("Save as Animation"), N_("Flatten Image") },
+  0
+};
+
+static ExportAction export_action_merge_or_flatten =
+{
+  export_flatten,
+  export_merge,
+  N_("%s plug-in can't handle layers"),
+  { N_("Flatten Image"), N_("Merge Visible Layers") },
+  1
+};
+
+static ExportAction export_action_flatten =
+{
+  export_flatten,
+  NULL,
+  N_("%s plug-in can't handle transparency"),
+  { N_("Flatten Image"), NULL },
+  0
+};
+
+static ExportAction export_action_remove_alpha =
+{
+  export_remove_alpha,
+  NULL,
+  N_("%s plug-in can't handle transparent layers"),
+  { N_("Flatten Image"), NULL },
+  0
+};
+
+static ExportAction export_action_apply_masks =
+{
+  export_apply_masks,
+  NULL,
+  N_("%s plug-in can't handle layer masks"),
+  { N_("Apply Layer Masks"), NULL },
+  0
+};
+
+static ExportAction export_action_convert_rgb =
+{
+  export_convert_rgb,
+  NULL,
+  N_("%s plug-in can only handle RGB images"),
+  { N_("Convert to RGB"), NULL },
+  0
+};
+
+static ExportAction export_action_convert_grayscale =
+{
+  export_convert_grayscale,
+  NULL,
+  N_("%s plug-in can only handle grayscale images"),
+  { N_("Convert to Grayscale"), NULL },
+  0
+};
+
+static ExportAction export_action_convert_indexed =
+{
+  export_convert_indexed,
+  NULL,
+  N_("%s plug-in can only handle indexed images"),
+  { N_("Convert to Indexed using default settings\n"
+       "(Do it manually to tune the result)"), NULL },
+  0
+};
+
+static ExportAction export_action_convert_bitmap =
+{
+  export_convert_bitmap,
+  NULL,
+  N_("%s plug-in can only handle bitmap (two color) indexed images"),
+  { N_("Convert to Indexed using bitmap default settings\n"
+       "(Do it manually to tune the result)"), NULL },
+  0
+};
+
+static ExportAction export_action_convert_rgb_or_grayscale =
+{
+  export_convert_rgb,
+  export_convert_grayscale,
+  N_("%s plug-in can only handle RGB or grayscale images"),
+  { N_("Convert to RGB"), N_("Convert to Grayscale")},
+  0
+};
+
+static ExportAction export_action_convert_rgb_or_indexed =
+{
+  export_convert_rgb,
+  export_convert_indexed,
+  N_("%s plug-in can only handle RGB or indexed images"),
+  { N_("Convert to RGB"), N_("Convert to Indexed using default settings\n"
+                             "(Do it manually to tune the result)")},
+  0
+};
+
+static ExportAction export_action_convert_indexed_or_grayscale =
+{
+  export_convert_indexed,
+  export_convert_grayscale,
+  N_("%s plug-in can only handle grayscale or indexed images"),
+  { N_("Convert to Indexed using default settings\n"
+       "(Do it manually to tune the result)"),
+    N_("Convert to Grayscale") },
+  0
+};
+
+static ExportAction export_action_add_alpha =
+{
+  export_add_alpha,
+  NULL,
+  N_("%s plug-in needs an alpha channel"),
+  { N_("Add Alpha Channel"), NULL},
+  0
+};
+
+static ExportAction export_action_crop_or_resize =
+{
+  export_crop_image,
+  export_resize_image,
+  N_("%s plug-in needs to crop the layers to the image bounds"),
+  { N_("Crop Layers"), N_("Resize Image to Layers")},
+  0
+};
+
+
+static ExportFunc
+export_action_get_func (const ExportAction *action)
+{
+  if (action->choice == 0 && action->default_action)
+    {
+      return action->default_action;
+    }
+
+  if (action->choice == 1 && action->alt_action)
+    {
+      return action->alt_action;
+    }
+
+  return export_void;
+}
+
+static void
+export_action_perform (const ExportAction *action,
+                       gint32              image_ID,
+                       gint32             *drawable_ID)
+{
+  export_action_get_func (action) (image_ID, drawable_ID);
+}
+
+
+/* dialog functions */
+
+static void
+export_toggle_callback (GtkWidget *widget,
+                        gpointer   data)
+{
+  gint *choice = (gint *) data;
+
+  if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (widget)))
+    *choice = FALSE;
+  else
+    *choice = TRUE;
+}
+
+static GimpExportReturn
+confirm_save_dialog (const gchar *message,
+                     const gchar *format_name)
+{
+  GtkWidget        *dialog;
+  GtkWidget        *hbox;
+  GtkWidget        *image;
+  GtkWidget        *main_vbox;
+  GtkWidget        *label;
+  gchar            *text;
+  GimpExportReturn  retval;
+
+  g_return_val_if_fail (message != NULL, GIMP_EXPORT_CANCEL);
+  g_return_val_if_fail (format_name != NULL, GIMP_EXPORT_CANCEL);
+
+  dialog = gimp_dialog_new (_("Confirm Save"), "gimp-export-image-confirm",
+                            NULL, 0,
+                            gimp_standard_help_func,
+                            "gimp-export-confirm-dialog",
+
+                            _("_Cancel"),  GTK_RESPONSE_CANCEL,
+                            _("C_onfirm"), GTK_RESPONSE_OK,
+
+                            NULL);
+
+  gtk_dialog_set_alternative_button_order (GTK_DIALOG (dialog),
+                                           GTK_RESPONSE_OK,
+                                           GTK_RESPONSE_CANCEL,
+                                           -1);
+
+  gtk_window_set_resizable (GTK_WINDOW (dialog), FALSE);
+  gimp_window_set_transient (GTK_WINDOW (dialog));
+
+  hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 12);
+  gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))),
+                      hbox, TRUE, TRUE, 0);
+  gtk_container_set_border_width (GTK_CONTAINER (hbox), 12);
+  gtk_widget_show (hbox);
+
+  image = gtk_image_new_from_icon_name ("dialog-warning",
+                                        GTK_ICON_SIZE_DIALOG);
+  gtk_misc_set_alignment (GTK_MISC (image), 0.5, 0.0);
+  gtk_box_pack_start (GTK_BOX (hbox), image, FALSE, FALSE, 0);
+  gtk_widget_show (image);
+
+  main_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
+  gtk_box_pack_start (GTK_BOX (hbox), main_vbox, FALSE, FALSE, 0);
+  gtk_widget_show (main_vbox);
+
+  text = g_strdup_printf (message, format_name);
+  label = gtk_label_new (text);
+  g_free (text);
+
+  gimp_label_set_attributes (GTK_LABEL (label),
+                             PANGO_ATTR_SCALE,  PANGO_SCALE_LARGE,
+                             PANGO_ATTR_WEIGHT, PANGO_WEIGHT_BOLD,
+                             -1);
+  gtk_label_set_xalign (GTK_LABEL (label), 0.0);
+  gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
+  gtk_label_set_justify (GTK_LABEL (label), GTK_JUSTIFY_LEFT);
+  gtk_box_pack_start (GTK_BOX (main_vbox), label, FALSE, FALSE, 0);
+  gtk_widget_show (label);
+
+  gtk_widget_show (dialog);
+
+  switch (gimp_dialog_run (GIMP_DIALOG (dialog)))
+    {
+    case GTK_RESPONSE_OK:
+      retval = GIMP_EXPORT_EXPORT;
+      break;
+
+    default:
+      retval = GIMP_EXPORT_CANCEL;
+      break;
+    }
+
+  gtk_widget_destroy (dialog);
+
+  return retval;
+}
+
+static GimpExportReturn
+export_dialog (GSList      *actions,
+               const gchar *format_name)
+{
+  GtkWidget        *dialog;
+  GtkWidget        *hbox;
+  GtkWidget        *image;
+  GtkWidget        *main_vbox;
+  GtkWidget        *label;
+  GSList           *list;
+  gchar            *text;
+  GimpExportReturn  retval;
+
+  g_return_val_if_fail (actions != NULL, GIMP_EXPORT_CANCEL);
+  g_return_val_if_fail (format_name != NULL, GIMP_EXPORT_CANCEL);
+
+  dialog = gimp_dialog_new (_("Export File"), "gimp-export-image",
+                            NULL, 0,
+                            gimp_standard_help_func, "gimp-export-dialog",
+
+                            _("_Ignore"), GTK_RESPONSE_NO,
+                            _("_Cancel"), GTK_RESPONSE_CANCEL,
+                            _("_Export"), GTK_RESPONSE_OK,
+
+                            NULL);
+
+  gtk_dialog_set_alternative_button_order (GTK_DIALOG (dialog),
+                                           GTK_RESPONSE_NO,
+                                           GTK_RESPONSE_OK,
+                                           GTK_RESPONSE_CANCEL,
+                                           -1);
+
+  gtk_window_set_resizable (GTK_WINDOW (dialog), FALSE);
+  gimp_window_set_transient (GTK_WINDOW (dialog));
+
+  hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 12);
+  gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))),
+                      hbox, TRUE, TRUE, 0);
+  gtk_container_set_border_width (GTK_CONTAINER (hbox), 12);
+  gtk_widget_show (hbox);
+
+  image = gtk_image_new_from_icon_name ("dialog-information",
+                                        GTK_ICON_SIZE_DIALOG);
+  gtk_misc_set_alignment (GTK_MISC (image), 0.5, 0.0);
+  gtk_box_pack_start (GTK_BOX (hbox), image, FALSE, FALSE, 0);
+  gtk_widget_show (image);
+
+  main_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
+  gtk_box_pack_start (GTK_BOX (hbox), main_vbox, FALSE, FALSE, 0);
+  gtk_widget_show (main_vbox);
+
+  /* the headline */
+  text = g_strdup_printf (_("Your image should be exported before it "
+                            "can be saved as %s for the following reasons:"),
+                          format_name);
+  label = gtk_label_new (text);
+  g_free (text);
+
+  gimp_label_set_attributes (GTK_LABEL (label),
+                             PANGO_ATTR_SCALE,  PANGO_SCALE_LARGE,
+                             -1);
+  gtk_label_set_xalign (GTK_LABEL (label), 0.0);
+  gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
+  gtk_label_set_justify (GTK_LABEL (label), GTK_JUSTIFY_LEFT);
+  gtk_box_pack_start (GTK_BOX (main_vbox), label, FALSE, FALSE, 0);
+  gtk_widget_show (label);
+
+  for (list = actions; list; list = g_slist_next (list))
+    {
+      ExportAction *action = list->data;
+      GtkWidget    *frame;
+      GtkWidget    *vbox;
+
+      text = g_strdup_printf (gettext (action->reason), format_name);
+      frame = gimp_frame_new (text);
+      g_free (text);
+
+      gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);
+      gtk_widget_show (frame);
+
+      vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 6);
+      gtk_container_add (GTK_CONTAINER (frame), vbox);
+
+      if (action->possibilities[0] && action->possibilities[1])
+        {
+          GtkWidget *button;
+          GSList    *radio_group = NULL;
+
+          button = gtk_radio_button_new_with_label (radio_group,
+                                                    gettext (action->possibilities[0]));
+          gtk_label_set_justify (GTK_LABEL (gtk_bin_get_child (GTK_BIN (button))),
+                                 GTK_JUSTIFY_LEFT);
+          radio_group = gtk_radio_button_get_group (GTK_RADIO_BUTTON (button));
+          gtk_box_pack_start (GTK_BOX (vbox), button, FALSE, FALSE, 0);
+          g_signal_connect (button, "toggled",
+                            G_CALLBACK (export_toggle_callback),
+                            &action->choice);
+          gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button),
+                                        (action->choice == 0));
+          gtk_widget_show (button);
+
+          button = gtk_radio_button_new_with_label (radio_group,
+                                                    gettext (action->possibilities[1]));
+          gtk_label_set_justify (GTK_LABEL (gtk_bin_get_child (GTK_BIN (button))),
+                                 GTK_JUSTIFY_LEFT);
+          radio_group = gtk_radio_button_get_group (GTK_RADIO_BUTTON (button));
+          gtk_box_pack_start (GTK_BOX (vbox), button, FALSE, FALSE, 0);
+          gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button),
+                                        (action->choice == 1));
+          gtk_widget_show (button);
+        }
+      else if (action->possibilities[0])
+        {
+          label = gtk_label_new (gettext (action->possibilities[0]));
+          gtk_label_set_xalign (GTK_LABEL (label), 0.0);
+          gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
+          gtk_label_set_justify (GTK_LABEL (label), GTK_JUSTIFY_LEFT);
+          gtk_box_pack_start (GTK_BOX (vbox), label, FALSE, FALSE, 0);
+          gtk_widget_show (label);
+          action->choice = 0;
+        }
+
+      gtk_widget_show (vbox);
+    }
+
+  /* the footline */
+  label = gtk_label_new (_("The export conversion won't modify your "
+                           "original image."));
+  gimp_label_set_attributes (GTK_LABEL (label),
+                             PANGO_ATTR_STYLE, PANGO_STYLE_ITALIC,
+                             -1);
+  gtk_label_set_xalign (GTK_LABEL (label), 0.0);
+  gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
+  gtk_label_set_justify (GTK_LABEL (label), GTK_JUSTIFY_LEFT);
+  gtk_box_pack_start (GTK_BOX (main_vbox), label, FALSE, FALSE, 0);
+  gtk_widget_show (label);
+
+  gtk_widget_show (dialog);
+
+  switch (gimp_dialog_run (GIMP_DIALOG (dialog)))
+    {
+    case GTK_RESPONSE_OK:
+      retval = GIMP_EXPORT_EXPORT;
+      break;
+
+    case GTK_RESPONSE_NO:
+      retval = GIMP_EXPORT_IGNORE;
+      break;
+
+    default:
+      retval = GIMP_EXPORT_CANCEL;
+      break;
+    }
+
+  gtk_widget_destroy (dialog);
+
+  return retval;
+}
+
+/**
+ * gimp_export_image:
+ * @image_ID: Pointer to the image_ID.
+ * @drawable_ID: Pointer to the drawable_ID.
+ * @format_name: The (short) name of the image_format (e.g. JPEG or GIF).
+ * @capabilities: What can the image_format do?
+ *
+ * Takes an image and a drawable to be saved together with a
+ * description of the capabilities of the image_format. If the
+ * type of image doesn't match the capabilities of the format
+ * a dialog is opened that informs the user that the image has
+ * to be exported and offers to do the necessary conversions.
+ *
+ * If the user chooses to export the image, a copy is created.
+ * This copy is then converted, the image_ID and drawable_ID
+ * are changed to point to the new image and the procedure returns
+ * GIMP_EXPORT_EXPORT. The save_plugin has to take care of deleting the
+ * created image using gimp_image_delete() when it has saved it.
+ *
+ * If the user chooses to Ignore the export problem, the image_ID
+ * and drawable_ID is not altered, GIMP_EXPORT_IGNORE is returned and
+ * the save_plugin should try to save the original image. If the
+ * user chooses Cancel, GIMP_EXPORT_CANCEL is returned and the
+ * save_plugin should quit itself with status %GIMP_PDB_CANCEL.
+ *
+ * If @format_name is NULL, no dialogs will be shown and this function
+ * will behave as if the user clicked on the 'Export' button, if a
+ * dialog would have been shown.
+ *
+ * Returns: An enum of #GimpExportReturn describing the user_action.
+ **/
+GimpExportReturn
+gimp_export_image (gint32                 *image_ID,
+                   gint32                 *drawable_ID,
+                   const gchar            *format_name,
+                   GimpExportCapabilities  capabilities)
+{
+  GSList            *actions = NULL;
+  GimpImageBaseType  type;
+  gint32             i;
+  gint32             n_layers;
+  gint32            *layers;
+  gboolean           interactive          = FALSE;
+  gboolean           added_flatten        = FALSE;
+  gboolean           has_layer_masks      = FALSE;
+  gboolean           background_has_alpha = TRUE;
+  GimpExportReturn   retval               = GIMP_EXPORT_CANCEL;
+
+  g_return_val_if_fail (*image_ID > -1 && *drawable_ID > -1, FALSE);
+
+  /* do some sanity checks */
+  if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
+    capabilities |= GIMP_EXPORT_CAN_HANDLE_ALPHA;
+
+  if (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS_AS_ANIMATION)
+    capabilities |= GIMP_EXPORT_CAN_HANDLE_LAYERS;
+
+  if (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYER_MASKS)
+    capabilities |= GIMP_EXPORT_CAN_HANDLE_LAYERS;
+
+  if (format_name && g_getenv ("GIMP_INTERACTIVE_EXPORT"))
+    interactive = TRUE;
+
+  /* ask for confirmation if the user is not saving a layer (see bug #51114) */
+  if (interactive &&
+      ! gimp_item_is_layer (*drawable_ID) &&
+      ! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
+    {
+      if (gimp_item_is_layer_mask (*drawable_ID))
+        {
+          retval = confirm_save_dialog
+            (_("You are about to save a layer mask as %s.\n"
+               "This will not save the visible layers."), format_name);
+        }
+      else if (gimp_item_is_channel (*drawable_ID))
+        {
+          retval = confirm_save_dialog
+            (_("You are about to save a channel (saved selection) as %s.\n"
+               "This will not save the visible layers."), format_name);
+        }
+      else
+        {
+          /* this should not happen */
+          g_warning ("%s: unknown drawable type!", G_STRFUNC);
+        }
+
+      /* cancel - the user can then select an appropriate layer to save */
+      if (retval == GIMP_EXPORT_CANCEL)
+        return GIMP_EXPORT_CANCEL;
+    }
+
+
+  /* check alpha and layer masks */
+  layers = gimp_image_get_layers (*image_ID, &n_layers);
+
+  for (i = 0; i < n_layers; i++)
+    {
+      if (gimp_drawable_has_alpha (layers[i]))
+        {
+          if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_ALPHA))
+            {
+              if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
+                {
+                  actions = g_slist_prepend (actions, &export_action_flatten);
+                  added_flatten = TRUE;
+                  break;
+                }
+              else
+                {
+                  actions = g_slist_prepend (actions, &export_action_remove_alpha);
+                  break;
+                }
+            }
+        }
+      else
+        {
+          /*  If this is the last layer, it's visible and has no alpha
+           *  channel, then the image has a "flat" background
+           */
+          if (i == n_layers - 1 && gimp_item_get_visible (layers[i]))
+            background_has_alpha = FALSE;
+
+          if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
+            {
+              actions = g_slist_prepend (actions, &export_action_add_alpha);
+              break;
+            }
+        }
+    }
+
+  if (! added_flatten)
+    {
+      for (i = 0; i < n_layers; i++)
+        {
+          if (gimp_layer_get_mask (layers[i]) != -1)
+            has_layer_masks = TRUE;
+        }
+    }
+
+  if (! added_flatten)
+    {
+      gint32  n_children;
+      gint32 *children;
+
+      children = gimp_item_get_children (layers[0], &n_children);
+
+      if ((capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS) &&
+          (capabilities & GIMP_EXPORT_NEEDS_CROP))
+        {
+          GeglRectangle image_bounds;
+          gboolean      needs_crop = FALSE;
+
+          image_bounds.x      = 0;
+          image_bounds.y      = 0;
+          image_bounds.width  = gimp_image_width  (*image_ID);
+          image_bounds.height = gimp_image_height (*image_ID);
+
+          for (i = 0; i < n_layers; i++)
+            {
+              GeglRectangle layer_bounds;
+
+              gimp_drawable_offsets (layers[i],
+                                     &layer_bounds.x, &layer_bounds.y);
+
+              layer_bounds.width  = gimp_drawable_width  (layers[i]);
+              layer_bounds.height = gimp_drawable_height (layers[i]);
+
+              if (! gegl_rectangle_contains (&image_bounds, &layer_bounds))
+                {
+                  needs_crop = TRUE;
+
+                  break;
+                }
+            }
+
+          if (needs_crop)
+            {
+              actions = g_slist_prepend (actions,
+                                         &export_action_crop_or_resize);
+            }
+        }
+
+      /* check if layer size != canvas size, opacity != 100%, or offsets != 0 */
+      if (n_layers == 1                     &&
+          ! children                        &&
+          gimp_item_is_layer (*drawable_ID) &&
+          ! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
+        {
+          gint offset_x;
+          gint offset_y;
+
+          gimp_drawable_offsets (*drawable_ID, &offset_x, &offset_y);
+
+          if ((gimp_layer_get_opacity (*drawable_ID) < 100.0) ||
+              (gimp_image_width (*image_ID) !=
+               gimp_drawable_width (*drawable_ID))            ||
+              (gimp_image_height (*image_ID) !=
+               gimp_drawable_height (*drawable_ID))           ||
+              offset_x || offset_y)
+            {
+              if (capabilities & GIMP_EXPORT_CAN_HANDLE_ALPHA)
+                {
+                  actions = g_slist_prepend (actions,
+                                             &export_action_merge_single);
+                }
+              else
+                {
+                  actions = g_slist_prepend (actions,
+                                             &export_action_flatten);
+                }
+            }
+        }
+      /* check multiple layers */
+      else if (n_layers > 1)
+        {
+          if (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS_AS_ANIMATION)
+            {
+              if (background_has_alpha ||
+                  capabilities & GIMP_EXPORT_NEEDS_ALPHA)
+                actions = g_slist_prepend (actions,
+                                           &export_action_animate_or_merge);
+              else
+                actions = g_slist_prepend (actions,
+                                           &export_action_animate_or_flatten);
+            }
+          else if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
+            {
+              if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
+                actions = g_slist_prepend (actions,
+                                           &export_action_merge);
+              else
+                actions = g_slist_prepend (actions,
+                                           &export_action_merge_or_flatten);
+            }
+        }
+      /* check for a single toplevel layer group */
+      else if (children)
+        {
+          if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
+            {
+              if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
+                actions = g_slist_prepend (actions,
+                                           &export_action_merge);
+              else
+                actions = g_slist_prepend (actions,
+                                           &export_action_merge_or_flatten);
+            }
+        }
+
+      g_free (children);
+
+      /* check layer masks */
+      if (has_layer_masks &&
+          ! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYER_MASKS))
+        actions = g_slist_prepend (actions, &export_action_apply_masks);
+    }
+
+  g_free (layers);
+
+  /* check the image type */
+  type = gimp_image_base_type (*image_ID);
+  switch (type)
+    {
+    case GIMP_RGB:
+      if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_RGB))
+        {
+          if ((capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED) &&
+              (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY))
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_indexed_or_grayscale);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_indexed);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_grayscale);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_BITMAP)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_bitmap);
+        }
+      break;
+
+    case GIMP_GRAY:
+      if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY))
+        {
+          if ((capabilities & GIMP_EXPORT_CAN_HANDLE_RGB) &&
+              (capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED))
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_rgb_or_indexed);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_RGB)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_rgb);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_indexed);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_BITMAP)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_bitmap);
+        }
+      break;
+
+    case GIMP_INDEXED:
+      if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED))
+        {
+          if ((capabilities & GIMP_EXPORT_CAN_HANDLE_RGB) &&
+              (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY))
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_rgb_or_grayscale);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_RGB)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_rgb);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY)
+            actions = g_slist_prepend (actions,
+                                       &export_action_convert_grayscale);
+          else if (capabilities & GIMP_EXPORT_CAN_HANDLE_BITMAP)
+            {
+              gint n_colors;
+
+              g_free (gimp_image_get_colormap (*image_ID, &n_colors));
+
+              if (n_colors > 2)
+                actions = g_slist_prepend (actions,
+                                           &export_action_convert_bitmap);
+            }
+        }
+      break;
+    }
+
+  if (actions)
+    {
+      actions = g_slist_reverse (actions);
+
+      if (interactive)
+        retval = export_dialog (actions, format_name);
+      else
+        retval = GIMP_EXPORT_EXPORT;
+    }
+  else
+    {
+      retval = GIMP_EXPORT_IGNORE;
+    }
+
+  if (retval == GIMP_EXPORT_EXPORT)
+    {
+      GSList *list;
+
+      *image_ID = gimp_image_duplicate (*image_ID);
+      *drawable_ID = gimp_image_get_active_layer (*image_ID);
+
+      gimp_image_undo_disable (*image_ID);
+
+      for (list = actions; list; list = list->next)
+        {
+          export_action_perform (list->data, *image_ID, drawable_ID);
+        }
+    }
+
+  g_slist_free (actions);
+
+  return retval;
+}
+
+/**
+ * gimp_export_dialog_new:
+ * @format_name: The short name of the image_format (e.g. JPEG or PNG).
+ * @role:        The dialog's @role which will be set with
+ *               gtk_window_set_role().
+ * @help_id:     The GIMP help id.
+ *
+ * Creates a new export dialog. All file plug-ins should use this
+ * dialog to get a consistent look on the export dialogs. Use
+ * gimp_export_dialog_get_content_area() to get a #GtkVBox to be
+ * filled with export options. The export dialog is a wrapped
+ * #GimpDialog.
+ *
+ * The dialog response when the user clicks on the Export button is
+ * %GTK_RESPONSE_OK, and when the Cancel button is clicked it is
+ * %GTK_RESPONSE_CANCEL.
+ *
+ * Returns: The new export dialog.
+ *
+ * Since: 2.8
+ **/
+GtkWidget *
+gimp_export_dialog_new (const gchar *format_name,
+                        const gchar *role,
+                        const gchar *help_id)
+{
+  GtkWidget *dialog;
+  /* TRANSLATORS: the %s parameter is an image format name (ex: PNG). */
+  gchar     *title  = g_strdup_printf (_("Export Image as %s"), format_name);
+
+  dialog = gimp_dialog_new (title, role,
+                            NULL, 0,
+                            gimp_standard_help_func, help_id,
+
+                            _("_Cancel"), GTK_RESPONSE_CANCEL,
+                            _("_Export"), GTK_RESPONSE_OK,
+
+                            NULL);
+
+  gtk_dialog_set_alternative_button_order (GTK_DIALOG (dialog),
+                                           GTK_RESPONSE_OK,
+                                           GTK_RESPONSE_CANCEL,
+                                           -1);
+
+  gimp_window_set_transient (GTK_WINDOW (dialog));
+
+  g_free (title);
+
+  return dialog;
+}
+
+/**
+ * gimp_export_dialog_get_content_area:
+ * @dialog: A dialog created with gimp_export_dialog_new()
+ *
+ * Returns the #GtkVBox of the passed export dialog to be filled with
+ * export options.
+ *
+ * Returns: The #GtkVBox to fill with export options.
+ *
+ * Since: 2.8
+ **/
+GtkWidget *
+gimp_export_dialog_get_content_area (GtkWidget *dialog)
+{
+  return gtk_dialog_get_content_area (GTK_DIALOG (dialog));
+}