gimp/app/core/gimpimage-rotate.c

/* The GIMP -- an 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 2 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include "config.h"

#include <glib-object.h>

#include "core-types.h"

#include "gimp.h"
#include "gimpcontext.h"
#include "gimpguide.h"
#include "gimpimage.h"
#include "gimpimage-rotate.h"
#include "gimpimage-guides.h"
#include "gimpimage-sample-points.h"
#include "gimpimage-undo.h"
#include "gimpimage-undo-push.h"
#include "gimpitem.h"
#include "gimplist.h"
#include "gimpprogress.h"


static void  gimp_image_rotate_item_offset   (GimpImage        *image,
                                              GimpRotationType  rotate_type,
                                              GimpItem         *item,
                                              gint              off_x,
                                              gint              off_y);
static void  gimp_image_rotate_guides        (GimpImage        *image,
                                              GimpRotationType  rotate_type);
static void  gimp_image_rotate_sample_points (GimpImage        *image,
                                              GimpRotationType  rotate_type);


void
gimp_image_rotate (GimpImage        *image,
                   GimpContext      *context,
                   GimpRotationType  rotate_type,
                   GimpProgress     *progress)
{
  GimpItem *item;
  GList    *list;
  gdouble   center_x;
  gdouble   center_y;
  gdouble   progress_max;
  gdouble   progress_current = 1.0;
  gint      new_image_width;
  gint      new_image_height;
  gboolean  size_changed;

  g_return_if_fail (GIMP_IS_IMAGE (image));
  g_return_if_fail (GIMP_IS_CONTEXT (context));
  g_return_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress));

  gimp_set_busy (image->gimp);

  center_x = (gdouble) image->width  / 2.0;
  center_y = (gdouble) image->height / 2.0;

  progress_max = (image->channels->num_children +
                  image->layers->num_children   +
                  image->vectors->num_children  +
                  1 /* selection */);

  g_object_freeze_notify (G_OBJECT (image));

  gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_IMAGE_ROTATE, NULL);

  /*  Resize the image (if needed)  */
  switch (rotate_type)
    {
    case GIMP_ROTATE_90:
    case GIMP_ROTATE_270:
      new_image_width  = image->height;
      new_image_height = image->width;
      size_changed     = TRUE;
      break;

    case GIMP_ROTATE_180:
      new_image_width  = image->width;
      new_image_height = image->height;
      size_changed     = FALSE;
     break;

    default:
      g_assert_not_reached ();
      return;
    }

  /*  Rotate all channels  */
  for (list = GIMP_LIST (image->channels)->list;
       list;
       list = g_list_next (list))
    {
      item = (GimpItem *) list->data;

      gimp_item_rotate (item, context, rotate_type, center_x, center_y, FALSE);

      item->offset_x = 0;
      item->offset_y = 0;

      if (progress)
        gimp_progress_set_value (progress, progress_current++ / progress_max);
    }

  /*  Rotate all vectors  */
  for (list = GIMP_LIST (image->vectors)->list;
       list;
       list = g_list_next (list))
    {
      item = (GimpItem *) list->data;

      gimp_item_rotate (item, context, rotate_type, center_x, center_y, FALSE);

      item->width    = new_image_width;
      item->height   = new_image_height;
      item->offset_x = 0;
      item->offset_y = 0;

      gimp_item_translate (item,
                           (new_image_width  - image->width)  / 2,
                           (new_image_height - image->height) / 2,
                           FALSE);

      if (progress)
        gimp_progress_set_value (progress, progress_current++ / progress_max);
    }

  /*  Don't forget the selection mask!  */
  gimp_item_rotate (GIMP_ITEM (gimp_image_get_mask (image)), context,
                    rotate_type, center_x, center_y, FALSE);

  GIMP_ITEM (image->selection_mask)->offset_x = 0;
  GIMP_ITEM (image->selection_mask)->offset_y = 0;

  if (progress)
    gimp_progress_set_value (progress, progress_current++ / progress_max);

  /*  Rotate all layers  */
  for (list = GIMP_LIST (image->layers)->list;
       list;
       list = g_list_next (list))
    {
      gint off_x, off_y;

      item = (GimpItem *) list->data;

      gimp_item_offsets (item, &off_x, &off_y);

      gimp_item_rotate (item, context, rotate_type, center_x, center_y, FALSE);

      gimp_image_rotate_item_offset (image, rotate_type, item, off_x, off_y);

      if (progress)
        gimp_progress_set_value (progress, progress_current++ / progress_max);
    }

  /*  Rotate all Guides  */
  gimp_image_rotate_guides (image, rotate_type);

  /*  Rotate all sample points  */
  gimp_image_rotate_sample_points (image, rotate_type);

  /*  Resize the image (if needed)  */
  if (size_changed)
    {
      gimp_image_undo_push_image_size (image, NULL);

      g_object_set (image,
                    "width",  new_image_width,
                    "height", new_image_height,
                    NULL);

      if (image->xresolution != image->yresolution)
        {
          gdouble tmp;

          gimp_image_undo_push_image_resolution (image, NULL);

          tmp                 = image->xresolution;
          image->yresolution = image->xresolution;
          image->xresolution = tmp;
        }
    }

  gimp_image_undo_group_end (image);

  if (size_changed)
    gimp_viewable_size_changed (GIMP_VIEWABLE (image));

  g_object_thaw_notify (G_OBJECT (image));

  gimp_unset_busy (image->gimp);
}


static void
gimp_image_rotate_item_offset (GimpImage        *image,
                               GimpRotationType  rotate_type,
                               GimpItem         *item,
                               gint              off_x,
                               gint              off_y)
{
  gint x = 0;
  gint y = 0;

  switch (rotate_type)
    {
    case GIMP_ROTATE_90:
      x = image->height - off_y - gimp_item_width (item);
      y = off_x;
      break;

    case GIMP_ROTATE_270:
      x = off_y;
      y = image->width - off_x - gimp_item_height (item);
      break;

    case GIMP_ROTATE_180:
      return;
    }

  gimp_item_offsets (item, &off_x, &off_y);

  x -= off_x;
  y -= off_y;

  if (x || y)
    gimp_item_translate (item, x, y, FALSE);
}

static void
gimp_image_rotate_guides (GimpImage        *image,
                          GimpRotationType  rotate_type)
{
  GList *list;

  /*  Rotate all Guides  */
  for (list = image->guides; list; list = g_list_next (list))
    {
      GimpGuide *guide = list->data;

      switch (rotate_type)
        {
        case GIMP_ROTATE_90:
          switch (guide->orientation)
            {
            case GIMP_ORIENTATION_HORIZONTAL:
              gimp_image_undo_push_image_guide (image, NULL, guide);
              guide->orientation = GIMP_ORIENTATION_VERTICAL;
              guide->position    = image->height - guide->position;
              break;

            case GIMP_ORIENTATION_VERTICAL:
              gimp_image_undo_push_image_guide (image, NULL, guide);
              guide->orientation = GIMP_ORIENTATION_HORIZONTAL;
              break;

            default:
              break;
            }
          break;

        case GIMP_ROTATE_180:
          switch (guide->orientation)
            {
            case GIMP_ORIENTATION_HORIZONTAL:
              gimp_image_move_guide (image, guide,
                                     image->height - guide->position, TRUE);
              break;

            case GIMP_ORIENTATION_VERTICAL:
              gimp_image_move_guide (image, guide,
                                     image->width - guide->position, TRUE);
              break;

            default:
              break;
            }
          break;

        case GIMP_ROTATE_270:
          switch (guide->orientation)
            {
            case GIMP_ORIENTATION_HORIZONTAL:
              gimp_image_undo_push_image_guide (image, NULL, guide);
              guide->orientation = GIMP_ORIENTATION_VERTICAL;
              break;

            case GIMP_ORIENTATION_VERTICAL:
              gimp_image_undo_push_image_guide (image, NULL, guide);
              guide->orientation = GIMP_ORIENTATION_HORIZONTAL;
              guide->position    = image->width - guide->position;
              break;

            default:
              break;
            }
          break;
        }
    }
}


static void
gimp_image_rotate_sample_points (GimpImage        *image,
                                 GimpRotationType  rotate_type)
{
  GList *list;

  /*  Rotate all sample points  */
  for (list = image->sample_points; list; list = g_list_next (list))
    {
      GimpSamplePoint *sample_point = list->data;
      gint             old_x;
      gint             old_y;

      old_x = sample_point->x;
      old_y = sample_point->y;

      switch (rotate_type)
        {
        case GIMP_ROTATE_90:
          sample_point->x = old_y;
          sample_point->y = image->height - old_x;
          break;

        case GIMP_ROTATE_180:
          sample_point->x = image->height - old_x;
          sample_point->y = image->width - old_y;
          break;

        case GIMP_ROTATE_270:
          sample_point->x = image->width - old_y;
          sample_point->y = old_x;
          break;
        }
    }
}