PIKApp/plug-ins/gfig/gfig.c

/*
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * This is a plug-in for PIKA.
 *
 * Generates images containing vector type drawings.
 *
 * Copyright (C) 1997 Andy Thomas  alt@picnic.demon.co.uk
 *
 * 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 <string.h>
#include <stdlib.h>
#include <errno.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <glib/gstdio.h>

#include <libpika/pika.h>
#include <libpika/pikaui.h>

#include "gfig.h"
#include "gfig-style.h"
#include "gfig-dialog.h"
#include "gfig-arc.h"
#include "gfig-bezier.h"
#include "gfig-circle.h"
#include "gfig-dobject.h"
#include "gfig-ellipse.h"
#include "gfig-grid.h"
#include "gfig-icons.h"
#include "gfig-line.h"
#include "gfig-poly.h"
#include "gfig-preview.h"
#include "gfig-spiral.h"
#include "gfig-star.h"

#include "libpika/stdplugins-intl.h"


#define GFIG_HEADER      "GFIG Version 0.2\n"

GType                   gfig_get_type         (void) G_GNUC_CONST;

static void             pika_gfig_finalize    (GObject              *object);

static GList          * gfig_query_procedures (PikaPlugIn           *plug_in);
static PikaProcedure  * gfig_create_procedure (PikaPlugIn           *plug_in,
                                               const gchar          *name);

static PikaValueArray * gfig_run              (PikaProcedure        *procedure,
                                               PikaRunMode           run_mode,
                                               PikaImage            *image,
                                               gint                  n_drawables,
                                               PikaDrawable        **drawables,
                                               const PikaValueArray *args,
                                               gpointer              run_data);

static void             on_app_activate       (GApplication         *gapp,
                                               gpointer              user_data);

static gint             load_options          (GFigObj              *gfig,
                                               FILE                 *fp);



G_DEFINE_TYPE (PikaGfig, pika_gfig, PIKA_TYPE_PLUG_IN)

PIKA_MAIN (PIKA_TYPE_GFIG)
DEFINE_STD_SET_I18N


gint line_no;

gint obj_show_single   = -1; /* -1 all >= 0 object number */

/* Structures etc for the objects */
/* Points used to draw the object  */

GfigObject *obj_creating; /* Object we are creating */
GfigObject *tmp_line;     /* Needed when drawing lines */

gboolean need_to_scale;

/* globals */

GfigObjectClass dobj_class[10];
GFigContext  *gfig_context;
GtkWidget    *top_level_dlg;
GList        *gfig_list;
gdouble       org_scale_x_factor, org_scale_y_factor;


/* Stuff for the preview bit */
static gint  sel_x, sel_y;
static gint  sel_width, sel_height;
gint         preview_width, preview_height;
gdouble      scale_x_factor, scale_y_factor;
GdkPixbuf   *back_pixbuf = NULL;


static void
pika_gfig_class_init (PikaGfigClass *klass)
{
  PikaPlugInClass *plug_in_class = PIKA_PLUG_IN_CLASS (klass);
  GObjectClass    *object_class  = G_OBJECT_CLASS (klass);

  object_class->finalize          = pika_gfig_finalize;

  plug_in_class->query_procedures = gfig_query_procedures;
  plug_in_class->create_procedure = gfig_create_procedure;
  plug_in_class->set_i18n         = STD_SET_I18N;
}

static void
pika_gfig_init (PikaGfig *gfig)
{
}

static void
pika_gfig_finalize (GObject *object)
{
  PikaGfig *gfig = PIKA_GFIG (object);

  G_OBJECT_CLASS (pika_gfig_parent_class)->finalize (object);

  g_clear_object (&gfig->builder);
}


static GList *
gfig_query_procedures (PikaPlugIn *plug_in)
{
  return g_list_append (NULL, g_strdup (PLUG_IN_PROC));
}

static PikaProcedure *
gfig_create_procedure (PikaPlugIn  *plug_in,
                       const gchar *name)
{
  PikaProcedure *procedure = NULL;

  if (! strcmp (name, PLUG_IN_PROC))
    {
      procedure = pika_image_procedure_new (plug_in, name,
                                            PIKA_PDB_PROC_TYPE_PLUGIN,
                                            gfig_run, NULL, NULL);

      pika_procedure_set_image_types (procedure, "RGB*, GRAY*");
      pika_procedure_set_sensitivity_mask (procedure,
                                           PIKA_PROCEDURE_SENSITIVE_DRAWABLE);

      pika_procedure_set_menu_label (procedure, _("_Gfig..."));
      pika_procedure_add_menu_path (procedure, "<Image>/Filters/Render");

      pika_procedure_set_documentation (procedure,
                                        _("Create geometric shapes"),
                                        "Draw Vector Graphics and paint them "
                                        "onto your images. Gfig allows you "
                                        "to draw many types of objects "
                                        "including Lines, Circles, Ellipses, "
                                        "Curves, Polygons, pointed stars, "
                                        "Bezier curves, and Spirals. "
                                        "Objects can be painted using "
                                        "Brushes or other tools or filled "
                                        "using colors or patterns. "
                                        "Gfig objects can also be used to "
                                        "create selections.",
                                        name);
      pika_procedure_set_attribution (procedure,
                                      "Andy Thomas",
                                      "Andy Thomas",
                                      "1997");
    }

  return procedure;
}

static PikaValueArray *
gfig_run (PikaProcedure        *procedure,
          PikaRunMode           run_mode,
          PikaImage            *image,
          gint                  n_drawables,
          PikaDrawable        **drawables,
          const PikaValueArray *args,
          gpointer              run_data)
{
  PikaDrawable      *drawable;
  PikaPDBStatusType  status = PIKA_PDB_SUCCESS;
  gint               pwidth, pheight;
  PikaGfig          *gfig;

  if (n_drawables != 1)
    {
      GError *error = NULL;

      g_set_error (&error, PIKA_PLUG_IN_ERROR, 0,
                   _("Procedure '%s' only works with one drawable."),
                   pika_procedure_get_name (procedure));

      return pika_procedure_new_return_values (procedure,
                                               PIKA_PDB_CALLING_ERROR,
                                               error);
    }
  else
    {
      drawable = drawables[0];
    }

  gfig          = PIKA_GFIG (pika_procedure_get_plug_in (procedure));
#if GLIB_CHECK_VERSION(2,74,0)
  gfig->app     = gtk_application_new (NULL, G_APPLICATION_DEFAULT_FLAGS);
#else
  gfig->app     = gtk_application_new (NULL, G_APPLICATION_FLAGS_NONE);
#endif
  gfig->success = FALSE;

  gfig->builder = gtk_builder_new_from_resource ("/technology.heckin/gfig/gfig-menu.ui");

  gfig_context = g_new0 (GFigContext, 1);

  gfig_context->show_background = TRUE;
  gfig_context->selected_obj    = NULL;

  gfig_context->image    = image;
  gfig_context->drawable = drawable;

  pika_image_undo_group_start (gfig_context->image);

  pika_context_push ();

  /* TMP Hack - clear any selections */
  if (! pika_selection_is_empty (gfig_context->image))
    pika_selection_none (gfig_context->image);

  if (! pika_drawable_mask_intersect (drawable, &sel_x, &sel_y,
                                      &sel_width, &sel_height))
    {
      pika_context_pop ();

      pika_image_undo_group_end (gfig_context->image);

      return pika_procedure_new_return_values (procedure, status, NULL);
    }

  /* Calculate preview size */

  if (sel_width > sel_height)
    {
      pwidth  = MIN (sel_width, PREVIEW_SIZE);
      pheight = sel_height * pwidth / sel_width;
    }
  else
    {
      pheight = MIN (sel_height, PREVIEW_SIZE);
      pwidth  = sel_width * pheight / sel_height;
    }

  preview_width  = MAX (pwidth, 2);  /* Min size is 2 */
  preview_height = MAX (pheight, 2);

  org_scale_x_factor = scale_x_factor =
    (gdouble) sel_width / (gdouble) preview_width;
  org_scale_y_factor = scale_y_factor =
    (gdouble) sel_height / (gdouble) preview_height;

  /* initialize */
  gfig_init_object_classes ();

  switch (run_mode)
    {
    case PIKA_RUN_INTERACTIVE:
    case PIKA_RUN_WITH_LAST_VALS:
      g_signal_connect (gfig->app, "activate", G_CALLBACK (on_app_activate), gfig);
      g_application_run (G_APPLICATION (gfig->app), 0, NULL);
      g_clear_object (&gfig->app);

      if (! gfig->success)
        {
          pika_image_undo_group_end (gfig_context->image);

          return pika_procedure_new_return_values (procedure, PIKA_PDB_CANCEL,
                                                   NULL);
        }
      break;

    case PIKA_RUN_NONINTERACTIVE:
      status = PIKA_PDB_CALLING_ERROR;
      break;

    default:
      break;
    }

  pika_context_pop ();

  pika_image_undo_group_end (gfig_context->image);

  if (run_mode != PIKA_RUN_NONINTERACTIVE)
    pika_displays_flush ();

  return pika_procedure_new_return_values (procedure, status, NULL);
}

static void
on_app_activate (GApplication *gapp,
                 gpointer      user_data)
{
  PikaGfig *gfig = PIKA_GFIG (user_data);

  gfig_dialog (gfig);

  gtk_application_set_accels_for_action (gfig->app, "app.open", (const char*[]) { "<control>O", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.save", (const char*[]) { "<control>S", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.close", (const char*[]) { "<control>C", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.undo", (const char*[]) { "<control>Z", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.clear", (const char*[]) { NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.grid", (const char*[]) { "<control>G", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.preferences", (const char*[]) { "<control>P", NULL });

  gtk_application_set_accels_for_action (gfig->app, "app.shape::line", (const char*[]) { "L", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::rectangle", (const char*[]) { "R", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::circle", (const char*[]) { "C", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::ellipse", (const char*[]) { "E", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::arc", (const char*[]) { "A", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::polygon", (const char*[]) { "P", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::star", (const char*[]) { "S", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::spiral", (const char*[]) { "I", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::bezier", (const char*[]) { "B", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::move-obj", (const char*[]) { "M", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::move-point", (const char*[]) { "V", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::copy", (const char*[]) { "Y", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::delete", (const char*[]) { "D", NULL });
  gtk_application_set_accels_for_action (gfig->app, "app.shape::select", (const char*[]) { "A", NULL });
}

/*
  Translate SPACE to "\\040", etc.
  Taken from gflare plugin
 */
void
gfig_name_encode (gchar *dest,
                  gchar *src)
{
  gint cnt = MAX_LOAD_LINE - 1;

  while (*src && cnt--)
    {
      if (g_ascii_iscntrl (*src) || g_ascii_isspace (*src) || *src == '\\')
        {
          sprintf (dest, "\\%03o", *src++);
          dest += 4;
        }
      else
        *dest++ = *src++;
    }
  *dest = '\0';
}

/*
  Translate "\\040" to SPACE, etc.
 */
void
gfig_name_decode (gchar       *dest,
                  const gchar *src)
{
  gint  cnt = MAX_LOAD_LINE - 1;
  guint tmp;

  while (*src && cnt--)
    {
      if (*src == '\\' && *(src+1) && *(src+2) && *(src+3))
        {
          sscanf (src+1, "%3o", &tmp);
          *dest++ = tmp;
          src += 4;
        }
      else
        *dest++ = *src++;
    }
  *dest = '\0';
}


/*
 * Load all gfig, which are founded in gfig-path-list, into gfig_list.
 * gfig-path-list must be initialized first. (plug_in_parse_gfig_path ())
 * based on code from Gflare.
 */

gint
gfig_list_pos (GFigObj *gfig)
{
  GFigObj *g;
  gint     n;
  GList   *tmp;

  n = 0;

  for (tmp = gfig_list; tmp; tmp = g_list_next (tmp))
    {
      g = tmp->data;

      if (strcmp (gfig->draw_name, g->draw_name) <= 0)
        break;

      n++;
    }
  return n;
}

/*
 *      Insert gfigs in alphabetical order
 */

gint
gfig_list_insert (GFigObj *gfig)
{
  gint n;

  n = gfig_list_pos (gfig);

  gfig_list = g_list_insert (gfig_list, gfig, n);

  return n;
}

void
gfig_free (GFigObj *gfig)
{
  g_assert (gfig != NULL);

  free_all_objs (gfig->obj_list);

  g_free (gfig->name);
  g_free (gfig->filename);
  g_free (gfig->draw_name);

  g_free (gfig);
}

GFigObj *
gfig_new (void)
{
  return g_new0 (GFigObj, 1);
}

static void
gfig_load_objs (PikaGfig *gfig,
                GFigObj  *gfig_obj,
                gint      load_count,
                FILE     *fp)
{
  GfigObject *obj;
  gchar       load_buf[MAX_LOAD_LINE];
  glong       offset;
  glong       offset2;
  Style       style;

  while (load_count-- > 0)
    {
      obj = NULL;
      get_line (load_buf, MAX_LOAD_LINE, fp, 0);

      /* kludge */
      offset = ftell (fp);
      gfig_skip_style (&style, fp);

      obj = d_load_object (load_buf, fp);

      if (obj)
        {
          add_to_all_obj (gfig, gfig_obj, obj);
          offset2 = ftell (fp);
          fseek (fp, offset, SEEK_SET);
          gfig_load_style (&obj->style, fp);
          fseek (fp, offset2, SEEK_SET);
        }
      else
        {
          g_message ("Failed to load object, load count = %d", load_count);
        }
    }
}

GFigObj *
gfig_load (PikaGfig    *gfig,
           const gchar *filename,
           const gchar *name)
{
  GFigObj *gfig_obj;
  FILE    *fp;
  gchar    load_buf[MAX_LOAD_LINE];
  gchar    str_buf[MAX_LOAD_LINE];
  gint     chk_count;
  gint     load_count = 0;
  gdouble  version;
  gchar    magic1[20];
  gchar    magic2[20];

  g_assert (filename != NULL);

#ifdef DEBUG
  printf ("Loading %s (%s)\n", filename, name);
#endif /* DEBUG */

  fp = g_fopen (filename, "rb");
  if (!fp)
    {
      g_message (_("Could not open '%s' for reading: %s"),
                 pika_filename_to_utf8 (filename), g_strerror (errno));
      return NULL;
    }

  gfig_obj = gfig_new ();

  gfig_obj->name = g_strdup (name);
  gfig_obj->filename = g_strdup (filename);


  /* HEADER
   * draw_name
   * version
   * obj_list
   */

  get_line (load_buf, MAX_LOAD_LINE, fp, 1);

  sscanf (load_buf, "%10s %10s %lf", magic1, magic2, &version);

  if (strcmp (magic1, "GFIG") || strcmp (magic2, "Version"))
    {
      g_message ("File '%s' is not a gfig file",
                  pika_filename_to_utf8 (gfig_obj->filename));
      gfig_free (gfig_obj);
      fclose (fp);
      return NULL;
    }

  get_line (load_buf, MAX_LOAD_LINE, fp, 0);
  sscanf (load_buf, "Name: %100s", str_buf);
  gfig_name_decode (load_buf, str_buf);
  gfig_obj->draw_name = g_strdup (load_buf);

  get_line (load_buf, MAX_LOAD_LINE, fp, 0);
  if (strncmp (load_buf, "Version: ", 9) == 0)
    gfig_obj->version = g_ascii_strtod (load_buf + 9, NULL);

  get_line (load_buf, MAX_LOAD_LINE, fp, 0);
  sscanf (load_buf, "ObjCount: %d", &load_count);

  if (load_options (gfig_obj, fp))
    {
      g_message ("File '%s' corrupt file - Line %d Option section incorrect",
                 pika_filename_to_utf8 (filename), line_no);
      gfig_free (gfig_obj);
      fclose (fp);
      return NULL;
    }

  if (gfig_load_styles (gfig_obj, fp))
    {
      g_message ("File '%s' corrupt file - Line %d Option section incorrect",
                 pika_filename_to_utf8 (filename), line_no);
      gfig_free (gfig_obj);
      fclose (fp);
      return NULL;
    }



  gfig_load_objs (gfig, gfig_obj, load_count, fp);

  /* Check count ? */

  chk_count = g_list_length (gfig_obj->obj_list);

  if (chk_count != load_count)
    {
      g_message ("File '%s' corrupt file - Line %d Object count to small",
                 pika_filename_to_utf8 (filename), line_no);
      gfig_free (gfig_obj);
      fclose (fp);
      return NULL;
    }

  fclose (fp);

  if (!gfig_context->current_obj)
    gfig_context->current_obj = gfig_obj;

  gfig_obj->obj_status = GFIG_OK;

  return gfig_obj;
}

void
save_options (GString *string)
{
  /* Save options */
  g_string_append_printf (string, "<OPTIONS>\n");
  g_string_append_printf (string, "GridSpacing: %d\n",
                          selvals.opts.gridspacing);
  if (selvals.opts.gridtype == RECT_GRID)
    {
      g_string_append_printf (string, "GridType: RECT_GRID\n");
    }
  else if (selvals.opts.gridtype == POLAR_GRID)
    {
      g_string_append_printf (string, "GridType: POLAR_GRID\n");
    }
  else if (selvals.opts.gridtype == ISO_GRID)
    {
      g_string_append_printf (string, "GridType: ISO_GRID\n");
    }
  else
    {
      /* default to RECT_GRID */
      g_string_append_printf (string, "GridType: RECT_GRID\n");
    }

  g_string_append_printf (string, "DrawGrid: %s\n",
                          (selvals.opts.drawgrid) ? "TRUE" : "FALSE");
  g_string_append_printf (string, "Snap2Grid: %s\n",
                          (selvals.opts.snap2grid) ? "TRUE" : "FALSE");
  g_string_append_printf (string, "LockOnGrid: %s\n",
                          (selvals.opts.lockongrid) ? "TRUE" : "FALSE");
  g_string_append_printf (string, "ShowControl: %s\n",
                          (selvals.opts.showcontrol) ? "TRUE" : "FALSE");
  g_string_append_printf (string, "</OPTIONS>\n");
}

static void
gfig_save_obj_start (GfigObject *obj,
                     GString    *string)
{
  g_string_append_printf (string, "<%s ", obj->class->name);
  gfig_style_save_as_attributes (&obj->style, string);
  g_string_append_printf (string, ">\n");
}

static void
gfig_save_obj_end (GfigObject *obj,
                   GString    *string)
{
  g_string_append_printf (string, "</%s>\n",obj->class->name);
}

static gboolean
load_bool (gchar *opt_buf,
           gint  *toset)
{
  if (!strcmp (opt_buf, "TRUE"))
    *toset = 1;
  else if (!strcmp (opt_buf, "FALSE"))
    *toset = 0;
  else
    return TRUE;

  return FALSE;
}

static gint
load_options (GFigObj *gfig,
              FILE    *fp)
{
  gchar load_buf[MAX_LOAD_LINE];
  gchar str_buf[MAX_LOAD_LINE];
  gchar opt_buf[MAX_LOAD_LINE];

  get_line (load_buf, MAX_LOAD_LINE, fp, 0);

#ifdef DEBUG
  printf ("load '%s'\n", load_buf);
#endif /* DEBUG */

  if (strcmp (load_buf, "<OPTIONS>"))
    return (-1);

  get_line (load_buf, MAX_LOAD_LINE, fp, 0);

#ifdef DEBUG
  printf ("opt line '%s'\n", load_buf);
#endif /* DEBUG */

  while (strcmp (load_buf, "</OPTIONS>"))
    {
      /* Get option name */
#ifdef DEBUG
      printf ("num = %d\n", sscanf (load_buf, "%255s %255s", str_buf, opt_buf));

      printf ("option %s val %s\n", str_buf, opt_buf);
#else
      sscanf (load_buf, "%255s %255s", str_buf, opt_buf);
#endif /* DEBUG */

      if (!strcmp (str_buf, "GridSpacing:"))
        {
          /* Value is decimal */
          int sp = 0;
          sp = atoi (opt_buf);
          if (sp <= 0)
            return (-1);
          gfig->opts.gridspacing = sp;
        }
      else if (!strcmp (str_buf, "DrawGrid:"))
        {
          /* Value is bool */
          if (load_bool (opt_buf, &gfig->opts.drawgrid))
            return (-1);
        }
      else if (!strcmp (str_buf, "Snap2Grid:"))
        {
          /* Value is bool */
          if (load_bool (opt_buf, &gfig->opts.snap2grid))
            return (-1);
        }
      else if (!strcmp (str_buf, "LockOnGrid:"))
        {
          /* Value is bool */
          if (load_bool (opt_buf, &gfig->opts.lockongrid))
            return (-1);
        }
      else if (!strcmp (str_buf, "ShowControl:"))
        {
          /* Value is bool */
          if (load_bool (opt_buf, &gfig->opts.showcontrol))
            return (-1);
        }
      else if (!strcmp (str_buf, "GridType:"))
        {
          /* Value is string */
          if (!strcmp (opt_buf, "RECT_GRID"))
            gfig->opts.gridtype = RECT_GRID;
          else if (!strcmp (opt_buf, "POLAR_GRID"))
            gfig->opts.gridtype = POLAR_GRID;
          else if (!strcmp (opt_buf, "ISO_GRID"))
            gfig->opts.gridtype = ISO_GRID;
          else
            return (-1);
        }

      get_line (load_buf, MAX_LOAD_LINE, fp, 0);

#ifdef DEBUG
      printf ("opt line '%s'\n", load_buf);
#endif /* DEBUG */
    }
  return (0);
}

GString *
gfig_save_as_string (void)
{
  GList    *objs;
  gint      count;
  gchar     buf[G_ASCII_DTOSTR_BUF_SIZE];
  gchar     conv_buf[MAX_LOAD_LINE * 3 + 1];
  GString  *string;

  string = g_string_new (GFIG_HEADER);

  gfig_name_encode (conv_buf, gfig_context->current_obj->draw_name);
  g_string_append_printf (string, "Name: %s\n", conv_buf);
  g_string_append_printf (string, "Version: %s\n",
                          g_ascii_formatd (buf, G_ASCII_DTOSTR_BUF_SIZE, "%f",
                                           gfig_context->current_obj->version));
  objs = gfig_context->current_obj->obj_list;

  count = g_list_length (objs);

  g_string_append_printf (string, "ObjCount: %d\n", count);

  save_options (string);

  gfig_save_styles (string);

  for (objs = gfig_context->current_obj->obj_list;
       objs;
       objs = g_list_next (objs))
    {
      GfigObject *object = objs->data;

      gfig_save_obj_start (object, string);

      gfig_save_style (&object->style, string);

      if (object->points)
        d_save_object (object, string);

      gfig_save_obj_end (object, string);
    }

  return string;
}


gboolean
gfig_save_as_parasite (void)
{
  PikaParasite *parasite;
  GString       *string;

  string = gfig_save_as_string ();

  parasite = pika_parasite_new ("gfig",
                                PIKA_PARASITE_PERSISTENT |
                                PIKA_PARASITE_UNDOABLE,
                                string->len, string->str);

  g_string_free (string, TRUE);

  if (!pika_item_attach_parasite (PIKA_ITEM (gfig_context->drawable),
                                  parasite))
    {
      g_message (_("Error trying to save figure as a parasite: "
                   "can't attach parasite to drawable."));
      pika_parasite_free (parasite);
      return FALSE;
    }

  pika_parasite_free (parasite);
  return TRUE;
}

GFigObj *
gfig_load_from_parasite (PikaGfig *gfig)
{
  GFile        *file;
  FILE         *fp;
  PikaParasite *parasite;
  const gchar  *parasite_data;
  guint32       parasite_size;
  GFigObj      *gfig_obj;

  parasite = pika_item_get_parasite (PIKA_ITEM (gfig_context->drawable),
                                     "gfig");
  if (! parasite)
    return NULL;

  file  = pika_temp_file ("gfigtmp");

  fp = g_fopen (g_file_peek_path (file), "wb");
  if (! fp)
    {
      g_message (_("Error trying to open temporary file '%s' "
                   "for parasite loading: %s"),
                 pika_file_get_utf8_name (file), g_strerror (errno));
      return NULL;
    }

  parasite_data = pika_parasite_get_data (parasite, &parasite_size);
  fwrite (parasite_data, sizeof (guchar), parasite_size, fp);
  fclose (fp);

  pika_parasite_free (parasite);

  gfig_obj = gfig_load (gfig, g_file_peek_path (file), "(none)");

  g_file_delete (file, NULL, NULL);

  g_object_unref (file);

  return gfig_obj;
}

void
gfig_save_callbk (void)
{
  FILE     *fp;
  gchar    *savename;
  GString  *string;

  savename = gfig_context->current_obj->filename;

  fp = g_fopen (savename, "w+b");

  if (!fp)
    {
      g_message (_("Could not open '%s' for writing: %s"),
                 pika_filename_to_utf8 (savename), g_strerror (errno));
      return;
    }

  string = gfig_save_as_string ();

  fwrite (string->str, string->len, 1, fp);

  if (ferror (fp))
    g_message ("Failed to write file.");
  else
    gfig_context->current_obj->obj_status &= ~(GFIG_MODIFIED | GFIG_READONLY);

  fclose (fp);
}