gimp/plug-ins/flame/flame.c

/* flame - cosmic recursive fractal flames
 * Copyright (C) 1997  Scott Draves <spot@cs.cmu.edu>
 *
 * 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 <errno.h>
#include <string.h>
#include <time.h>

#include <glib/gstdio.h>

#include <libgimp/gimp.h>
#include <libgimp/gimpui.h>

#include "flame.h"

#include "libgimp/stdplugins-intl.h"


#define PLUG_IN_PROC      "plug-in-flame"
#define PLUG_IN_BINARY    "flame"
#define PLUG_IN_ROLE      "gimp-flame"

#define VARIATION_SAME    (-2)

#define BUFFER_SIZE       10000

#define PREVIEW_SIZE      150
#define EDIT_PREVIEW_SIZE 85
#define NMUTANTS          9

#define BLACK_DRAWABLE    (-2)
#define GRADIENT_DRAWABLE (-3)
#define TABLE_DRAWABLE    (-4)


typedef struct
{
  gint          randomize;  /* superseded */
  gint          variation;
  gint32        cmap_drawable_id;
  control_point cp;
} FlameSettings;

FlameSettings config;


typedef struct _Flame      Flame;
typedef struct _FlameClass FlameClass;

struct _Flame
{
  GimpPlugIn parent_instance;
};

struct _FlameClass
{
  GimpPlugInClass parent_class;
};


#define FLAME_TYPE  (flame_get_type ())
#define FLAME(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), FLAME_TYPE, Flame))

GType                   flame_get_type         (void) G_GNUC_CONST;

static GList          * flame_query_procedures (GimpPlugIn           *plug_in);
static GimpProcedure  * flame_create_procedure (GimpPlugIn           *plug_in,
                                                const gchar          *name);

static GimpValueArray * flame_run              (GimpProcedure        *procedure,
                                                GimpRunMode           run_mode,
                                                GimpImage            *image,
                                                gint                  n_drawables,
                                                GimpDrawable        **drawables,
                                                GimpProcedureConfig  *proc_config,
                                                gpointer              run_data);

static void             flame                  (GimpDrawable         *drawable);

static gboolean         flame_dialog           (Flame                *flame,
                                                GimpProcedure        *procedure,
                                                GimpProcedureConfig  *proc_config);
static void             set_flame_preview      (GimpProcedureConfig  *proc_config);
static void             load_callback          (GtkWidget            *widget,
                                                GimpProcedureConfig  *proc_config);
static void             save_callback          (GtkWidget            *widget,
                                                GimpProcedureConfig  *proc_config);
static void             set_edit_preview       (GimpProcedureConfig  *proc_config);
static void             combo_callback         (GtkWidget            *widget,
                                                gpointer              data);
static void             init_mutants           (GimpProcedureConfig  *proc_config);

static void    flame_scale_entry_update_double (GimpLabelSpin        *entry,
                                                gdouble              *value);

static void          flame_update_settings_aux (GimpProcedureConfig  *proc_config);


G_DEFINE_TYPE (Flame, flame, GIMP_TYPE_PLUG_IN)

GIMP_MAIN (FLAME_TYPE)
DEFINE_STD_SET_I18N


static gchar      buffer[BUFFER_SIZE];
static GtkWidget *cmap_preview;
static GtkWidget *flame_preview;
static gint       preview_width, preview_height;
static GtkWidget *dialog;
static GtkWidget *load_button = NULL;
static GtkWidget *save_button = NULL;
static GtkWidget *file_dialog = NULL;
static gint       load_save;

static GtkWidget *edit_dialog = NULL;

static control_point  edit_cp;
static control_point  mutants[NMUTANTS];
static GtkWidget     *edit_previews[NMUTANTS];
static gdouble        pick_speed = 0.2;

static frame_spec f = { 0.0, &config.cp, 1, 0.0 };


static void
flame_class_init (FlameClass *klass)
{
  GimpPlugInClass *plug_in_class = GIMP_PLUG_IN_CLASS (klass);

  plug_in_class->query_procedures = flame_query_procedures;
  plug_in_class->create_procedure = flame_create_procedure;
  plug_in_class->set_i18n         = STD_SET_I18N;
}

static void
flame_init (Flame *flame)
{
}

static GList *
flame_query_procedures (GimpPlugIn *plug_in)
{
  return g_list_append (NULL, g_strdup (PLUG_IN_PROC));
}

static GimpProcedure *
flame_create_procedure (GimpPlugIn  *plug_in,
                        const gchar *name)
{
  GimpProcedure *procedure = NULL;

  if (! strcmp (name, PLUG_IN_PROC))
    {
      procedure = gimp_image_procedure_new (plug_in, name,
                                            GIMP_PDB_PROC_TYPE_PLUGIN,
                                            flame_run, NULL, NULL);

      gimp_procedure_set_image_types (procedure, "RGB*");
      gimp_procedure_set_sensitivity_mask (procedure,
                                           GIMP_PROCEDURE_SENSITIVE_DRAWABLE);

      gimp_procedure_set_menu_label (procedure, _("_Flame..."));
      gimp_procedure_add_menu_path (procedure,
                                    "<Image>/Filters/Render/Fractals");

      gimp_procedure_set_documentation (procedure,
                                        _("Create cosmic recursive fractal "
                                          "flames"),
                                        "Create cosmic recursive fractal flames",
                                        name);
      gimp_procedure_set_attribution (procedure,
                                      "Scott Draves",
                                      "Scott Draves",
                                      "1997");

      gimp_procedure_add_double_argument (procedure, "brightness",
                                          _("_Brightness"), NULL,
                                          0.0, 5.0, 1.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_double_argument (procedure, "contrast",
                                          _("Co_ntrast"), NULL,
                                          0.0, 5.0, 1.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_double_argument (procedure, "gamma",
                                          _("_Gamma"), NULL,
                                          1.0, 5.0, 1.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_double_argument (procedure, "sample-density",
                                          _("Sample _density"), NULL,
                                          0.1, 20.0, 5.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_int_argument (procedure, "spatial-oversample",
                                          _("Spa_tial oversample"), NULL,
                                          1, 4, 2.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_double_argument (procedure, "spatial-filter-radius",
                                          _("Spatial _filter radius"), NULL,
                                          0.0, 4.0, 0.75,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_double_argument (procedure, "zoom",
                                          _("_Zoom"), NULL,
                                          -4.0, 4.0, 0.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_double_argument (procedure, "x",
                                          _("_X"), NULL,
                                          -2.0, 2.0, 0.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_double_argument (procedure, "y",
                                          _("_Y"), NULL,
                                          -2.0, 2.0, 0.0,
                                          G_PARAM_READWRITE);

      gimp_procedure_add_bytes_aux_argument (procedure, "settings-data",
                                             "Settings data",
                                             "TODO: eventually we must implement proper args for every settings",
                                             GIMP_PARAM_READWRITE);
    }

  return procedure;
}

static void
maybe_init_cp (GimpProcedureConfig *proc_config)
{
  if (0 == config.cp.spatial_oversample)
    {
      config.randomize        = 0;
      config.variation        = VARIATION_SAME;
      config.cmap_drawable_id = GRADIENT_DRAWABLE;

      random_control_point (&config.cp, variation_random);

      config.cp.center[0]             = 0.0;
      config.cp.center[1]             = 0.0;
      config.cp.pixels_per_unit       = 100;
      config.cp.spatial_oversample    = 2;
      config.cp.gamma                 = 2.0;
      config.cp.contrast              = 1.0;
      config.cp.brightness            = 1.0;
      config.cp.spatial_filter_radius = 0.75;
      config.cp.sample_density        = 5.0;
      config.cp.zoom                  = 0.0;
      config.cp.nbatches              = 1;
      config.cp.white_level           = 200;
      config.cp.cmap_index            = 72;
      /* cheating */
      config.cp.width                 = 256;
      config.cp.height                = 256;

      flame_update_settings_aux (proc_config);
    }
}

static GimpValueArray *
flame_run (GimpProcedure        *procedure,
           GimpRunMode           run_mode,
           GimpImage            *image,
           gint                  n_drawables,
           GimpDrawable        **drawables,
           GimpProcedureConfig  *proc_config,
           gpointer              run_data)
{
  GimpDrawable *drawable;
  GBytes       *settings_bytes = NULL;

  gegl_init (NULL, NULL);

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

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

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

  if (run_mode == GIMP_RUN_NONINTERACTIVE)
    {
      return gimp_procedure_new_return_values (procedure,
                                               GIMP_PDB_CALLING_ERROR,
                                               NULL);
    }

  g_object_get (proc_config, "settings-data", &settings_bytes, NULL);
  if (settings_bytes != NULL)
    {
      if (g_bytes_get_size (settings_bytes) == sizeof (FlameSettings))
        config = *((FlameSettings *) g_bytes_get_data (settings_bytes, NULL));

      g_bytes_unref (settings_bytes);
    }

  maybe_init_cp (proc_config);

  config.cp.width  = gimp_drawable_get_width  (drawable);
  config.cp.height = gimp_drawable_get_height (drawable);

  if (run_mode == GIMP_RUN_INTERACTIVE)
    {
      if (! flame_dialog (FLAME (gimp_procedure_get_plug_in (procedure)), procedure, proc_config))
        {
          return gimp_procedure_new_return_values (procedure,
                                                   GIMP_PDB_CANCEL,
                                                   NULL);
        }
    }

  if (gimp_drawable_is_rgb (drawable))
    {
      gimp_progress_init (_("Drawing flame"));

      flame (drawable);

      if (run_mode != GIMP_RUN_NONINTERACTIVE)
        gimp_displays_flush ();
    }
  else
    {
      return gimp_procedure_new_return_values (procedure,
                                               GIMP_PDB_EXECUTION_ERROR,
                                               NULL);
    }

   /*  reusing a drawable from the last run is a bad idea
    *  since the drawable might have vanished  (bug #37761)
    */
   if (config.cmap_drawable_id > 0)
     config.cmap_drawable_id = GRADIENT_DRAWABLE;

  flame_update_settings_aux (proc_config);

  return gimp_procedure_new_return_values (procedure, GIMP_PDB_SUCCESS, NULL);
}

static void
drawable_to_cmap (control_point *cp)
{
  gint i, j;

  if (TABLE_DRAWABLE >= config.cmap_drawable_id)
    {
      i = TABLE_DRAWABLE - config.cmap_drawable_id;
      get_cmap (i, cp->cmap, 256);
    }
  else if (BLACK_DRAWABLE == config.cmap_drawable_id)
    {
      for (i = 0; i < 256; i++)
        for (j = 0; j < 3; j++)
          cp->cmap[i][j] = 0.0;
    }
  else if (GRADIENT_DRAWABLE == config.cmap_drawable_id)
    {
      GimpGradient *gradient = gimp_context_get_gradient ();

      gint     num;
      gdouble *g;

      /* FIXME: "reverse" hardcoded to FALSE. */
      gimp_gradient_get_uniform_samples (gradient, 256, FALSE,
                                         &num, &g);


      for (i = 0; i < 256; i++)
        for (j = 0; j < 3; j++)
          cp->cmap[i][j] = g[i*4 + j];
      g_free (g);
    }
  else
    {
      GimpDrawable *drawable = gimp_drawable_get_by_id (config.cmap_drawable_id);
      GeglBuffer   *buffer   = gimp_drawable_get_buffer (drawable);
      gint          width    = gegl_buffer_get_width  (buffer);
      gint          height   = gegl_buffer_get_height (buffer);
      guchar        p[3];

      for (i = 0; i < 256; i++)
        {
          gegl_buffer_sample (buffer,
                              i % width,
                              (i / width) % height,
                              NULL, p, babl_format ("R'G'B' u8"),
                              GEGL_SAMPLER_NEAREST, GEGL_ABYSS_NONE);

          for (j = 0; j < 3; j++)
            cp->cmap[i][j] = p[j] / 255.0;
        }

      g_object_unref (buffer);
    }
}

static void
flame (GimpDrawable *drawable)
{
  const Babl *format;
  gint        width, height;
  guchar     *tmp;
  gint        bytes;

  width  = gimp_drawable_get_width  (drawable);
  height = gimp_drawable_get_height (drawable);

  if (gimp_drawable_has_alpha (drawable))
    format = babl_format ("R'G'B'A u8");
  else
    format = babl_format ("R'G'B' u8");

  bytes = babl_format_get_bytes_per_pixel (format);

  tmp = g_new (guchar, width * height * 4);

  /* render */
  config.cp.width = width;
  config.cp.height = height;
  if (config.randomize)
    random_control_point (&config.cp, config.variation);
  drawable_to_cmap (&config.cp);
  render_rectangle (&f, tmp, width, field_both, 4,
                    gimp_progress_update);
  gimp_progress_update (1.0);

  /* update destination */
  if (bytes == 4)
    {
      GeglBuffer *buffer = gimp_drawable_get_shadow_buffer (drawable);

      gegl_buffer_set (buffer, GEGL_RECTANGLE (0, 0, width, height), 0,
                       format, tmp,
                       GEGL_AUTO_ROWSTRIDE);

      g_object_unref (buffer);
    }
  else if (bytes == 3)
    {
      GeglBuffer *src_buffer  = gimp_drawable_get_buffer (drawable);
      GeglBuffer *dest_buffer = gimp_drawable_get_shadow_buffer (drawable);
      gint        i, j;
      guchar     *sl;

      sl = g_new (guchar, 3 * width);

      for (i = 0; i < height; i++)
        {
          guchar *rr = tmp + 4 * i * width;
          guchar *sld = sl;

          gegl_buffer_get (src_buffer, GEGL_RECTANGLE (0, i, width, 1), 1.0,
                           format, sl,
                           GEGL_AUTO_ROWSTRIDE, GEGL_ABYSS_NONE);

          for (j = 0; j < width; j++)
            {
              gint k, alpha = rr[3];

              for (k = 0; k < 3; k++)
                {
                  gint t = (rr[k] + ((sld[k] * (256-alpha)) >> 8));

                  if (t > 255) t = 255;
                  sld[k] = t;
                }
              rr += 4;
              sld += 3;
            }

          gegl_buffer_set (dest_buffer, GEGL_RECTANGLE (0, i, width, 1), 0,
                           format, sl,
                           GEGL_AUTO_ROWSTRIDE);
        }

      g_free (sl);

      g_object_unref (src_buffer);
      g_object_unref (dest_buffer);
    }

  g_free (tmp);

  gimp_drawable_merge_shadow (drawable, TRUE);
  gimp_drawable_update (drawable, 0, 0, width, height);
}

static void
file_response_callback (GtkFileChooser      *chooser,
                        gint                 response_id,
                        GimpProcedureConfig *proc_config)
{
  if (response_id == GTK_RESPONSE_OK)
    {
      gchar *filename = gtk_file_chooser_get_filename (chooser);

      if (load_save)
        {
          FILE  *f;
          gint   i, c;
          gchar *ss;

          if (!g_file_test (filename, G_FILE_TEST_IS_REGULAR))
            {
              g_message (_("'%s' is not a regular file"),
                         gimp_filename_to_utf8 (filename));
              g_free (filename);
              return;
            }

          f = g_fopen (filename, "rb");

          if (f == NULL)
            {
              g_message (_("Could not open '%s' for reading: %s"),
                         gimp_filename_to_utf8 (filename), g_strerror (errno));
              g_free (filename);
              return;
            }

          i = 0;
          ss = buffer;
          do
            {
              c = getc (f);
              if (EOF == c)
                break;
              ss[i++] = c;
            }
          while (i < BUFFER_SIZE && ';' != c);
          parse_control_point (&ss, &config.cp);
          fclose (f);

          g_signal_handlers_block_by_func (proc_config,
                                           G_CALLBACK (set_flame_preview),
                                           NULL);
          flame_update_settings_aux (proc_config);
          g_object_set (proc_config,
                        "x",                     config.cp.center[0],
                        "y",                     config.cp.center[1],
                        "spatial-oversample",    config.cp.spatial_oversample,
                        "gamma",                 config.cp.gamma,
                        "contrast",              config.cp.contrast,
                        "brightness",            config.cp.brightness,
                        "spatial-filter-radius", config.cp.spatial_filter_radius,
                        "sample-density",        config.cp.sample_density,
                        "zoom",                  config.cp.zoom,
                        NULL);
          g_signal_handlers_unblock_by_func (proc_config,
                                             G_CALLBACK (set_flame_preview),
                                             NULL);
          set_flame_preview (proc_config);
          set_edit_preview (proc_config);
        }
      else
        {
          FILE *f = g_fopen (filename, "wb");

          if (NULL == f)
            {
              g_message (_("Could not open '%s' for writing: %s"),
                         gimp_filename_to_utf8 (filename), g_strerror (errno));
              g_free (filename);
              return;
            }

          print_control_point (f, &config.cp, 0);
          fclose (f);
        }

      g_free (filename);
    }

  gtk_widget_destroy (GTK_WIDGET (chooser));

  if (! gtk_widget_get_sensitive (load_button))
    gtk_widget_set_sensitive (load_button, TRUE);

  if (! gtk_widget_get_sensitive (save_button))
    gtk_widget_set_sensitive (save_button, TRUE);
}

static void
make_file_dialog (const gchar         *title,
                  GtkWidget           *parent,
                  GimpProcedureConfig *proc_config)
{
  file_dialog = gtk_file_chooser_dialog_new (title, GTK_WINDOW (parent),
                                             load_save ?
                                             GTK_FILE_CHOOSER_ACTION_OPEN :
                                             GTK_FILE_CHOOSER_ACTION_SAVE,

                                             _("_Cancel"), GTK_RESPONSE_CANCEL,
                                             load_save ?
                                             _("_Open") : _("_Save"),
                                             GTK_RESPONSE_OK,

                                             NULL);

  gtk_dialog_set_default_response (GTK_DIALOG (file_dialog), GTK_RESPONSE_OK);
  gimp_dialog_set_alternative_button_order (GTK_DIALOG (file_dialog),
                                           GTK_RESPONSE_OK,
                                           GTK_RESPONSE_CANCEL,
                                           -1);

  if (! load_save)
    gtk_file_chooser_set_do_overwrite_confirmation (GTK_FILE_CHOOSER (file_dialog),
                                                    TRUE);

  g_object_add_weak_pointer (G_OBJECT (file_dialog), (gpointer) &file_dialog);

  gtk_window_set_destroy_with_parent (GTK_WINDOW (file_dialog), TRUE);

  g_signal_connect (file_dialog, "delete-event",
                    G_CALLBACK (gtk_true),
                    NULL);
  g_signal_connect (file_dialog, "response",
                    G_CALLBACK (file_response_callback),
                    proc_config);
}

static void
randomize_callback (GtkWidget           *widget,
                    GimpProcedureConfig *proc_config)
{
  random_control_point (&edit_cp, config.variation);
  init_mutants (proc_config);
  set_edit_preview (proc_config);
}

static void
edit_response (GtkWidget           *widget,
               gint                 response_id,
               GimpProcedureConfig *proc_config)
{
  gtk_widget_hide (widget);

  if (response_id == GTK_RESPONSE_OK)
    {
      config.cp = edit_cp;

      g_signal_handlers_block_by_func (proc_config,
                                       G_CALLBACK (set_flame_preview),
                                       NULL);
      flame_update_settings_aux (proc_config);
      g_object_set (proc_config,
                    "x",                     config.cp.center[0],
                    "y",                     config.cp.center[1],
                    "spatial-oversample",    config.cp.spatial_oversample,
                    "gamma",                 config.cp.gamma,
                    "contrast",              config.cp.contrast,
                    "brightness",            config.cp.brightness,
                    "spatial-filter-radius", config.cp.spatial_filter_radius,
                    "sample-density",        config.cp.sample_density,
                    "zoom",                  config.cp.zoom,
                    NULL);
      g_signal_handlers_unblock_by_func (proc_config,
                                         G_CALLBACK (set_flame_preview),
                                         NULL);
      set_flame_preview (proc_config);
    }
}

static void
init_mutants (GimpProcedureConfig *proc_config)
{
  gint i;

  for (i = 0; i < NMUTANTS; i++)
    {
      mutants[i] = edit_cp;
      random_control_point (mutants + i, config.variation);
      if (VARIATION_SAME == config.variation)
        copy_variation (mutants + i, &edit_cp);
    }

  flame_update_settings_aux (proc_config);
}

static void
set_edit_preview (GimpProcedureConfig *proc_config)
{
  gint           i, j;
  guchar        *b;
  control_point  pcp;
  gint           nbytes = EDIT_PREVIEW_SIZE * EDIT_PREVIEW_SIZE * 3;

  static frame_spec pf = { 0.0, 0, 1, 0.0 };

  if (NULL == edit_previews[0])
    return;

  b = g_new (guchar, nbytes);
  maybe_init_cp (proc_config);
  drawable_to_cmap (&edit_cp);
  for (i = 0; i < 3; i++)
    for (j = 0; j < 3; j++)
      {
        gint mut = i*3 + j;

        pf.cps = &pcp;
        if (1 == i && 1 == j)
          {
            pcp = edit_cp;
          }
        else
          {
            control_point ends[2];
            ends[0] = edit_cp;
            ends[1] = mutants[mut];
            ends[0].time = 0.0;
            ends[1].time = 1.0;
            interpolate (ends, 2, pick_speed, &pcp);
          }
        pcp.pixels_per_unit =
          (pcp.pixels_per_unit * EDIT_PREVIEW_SIZE) / pcp.width;
        pcp.width = EDIT_PREVIEW_SIZE;
        pcp.height = EDIT_PREVIEW_SIZE;

        pcp.sample_density = 1;
        pcp.spatial_oversample = 1;
        pcp.spatial_filter_radius = 0.5;

        drawable_to_cmap (&pcp);

        render_rectangle (&pf, b, EDIT_PREVIEW_SIZE, field_both, 3, NULL);

        gimp_preview_area_draw (GIMP_PREVIEW_AREA (edit_previews[mut]),
                                0, 0, EDIT_PREVIEW_SIZE, EDIT_PREVIEW_SIZE,
                                GIMP_RGB_IMAGE,
                                b,
                                EDIT_PREVIEW_SIZE * 3);
      }

  g_free (b);
}

static void
edit_preview_size_allocate (GtkWidget           *widget,
                            GimpProcedureConfig *proc_config)
{
  set_edit_preview (proc_config);
}

static void
preview_clicked (GtkWidget *widget,
                 gpointer   data)
{
  GimpProcedureConfig *proc_config;
  gint                 mut = GPOINTER_TO_INT (data);

  proc_config = g_object_get_data (G_OBJECT (widget), "config");

  if (mut == 4)
    {
      control_point t = edit_cp;
      init_mutants (proc_config);
      edit_cp = t;
    }
  else
    {
      control_point ends[2];
      ends[0] = edit_cp;
      ends[1] = mutants[mut];
      ends[0].time = 0.0;
      ends[1].time = 1.0;
      interpolate (ends, 2, pick_speed, &edit_cp);
    }
  set_edit_preview (proc_config);
}

static void
edit_callback (GtkWidget *widget,
               GtkWidget *parent)
{
  GimpProcedureConfig *proc_config;

  proc_config = g_object_get_data (G_OBJECT (parent), "config");
  edit_cp     = config.cp;

  if (edit_dialog == NULL)
    {
      GtkWidget *main_vbox;
      GtkWidget *frame;
      GtkWidget *grid;
      GtkWidget *vbox;
      GtkWidget *hbox;
      GtkWidget *button;
      GtkWidget *combo;
      GtkWidget *label;
      GtkWidget *scale;
      gint       i, j;

      edit_dialog = gimp_dialog_new (_("Edit Flame"), PLUG_IN_ROLE,
                                     parent, GTK_DIALOG_DESTROY_WITH_PARENT,
                                     gimp_standard_help_func, PLUG_IN_PROC,

                                     _("_Cancel"), GTK_RESPONSE_CANCEL,
                                     _("_OK"),     GTK_RESPONSE_OK,

                                     NULL);

      gimp_dialog_set_alternative_button_order (GTK_DIALOG (edit_dialog),
                                               GTK_RESPONSE_OK,
                                               GTK_RESPONSE_CANCEL,
                                               -1);

      g_signal_connect (edit_dialog, "response",
                        G_CALLBACK (edit_response),
                        proc_config);

      main_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
      gtk_container_set_border_width (GTK_CONTAINER (main_vbox), 12);
      gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (edit_dialog))),
                          main_vbox, FALSE, FALSE, 0);

      frame = gimp_frame_new (_("Directions"));
      gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);
      gtk_widget_show (frame);

      grid = gtk_grid_new ();
      gtk_grid_set_row_spacing (GTK_GRID (grid), 6);
      gtk_grid_set_column_spacing (GTK_GRID (grid), 6);
      gtk_container_add (GTK_CONTAINER (frame), grid);
      gtk_widget_show (grid);

      for (i = 0; i < 3; i++)
        for (j = 0; j < 3; j++)
          {
            gint mut = i * 3 + j;

            edit_previews[mut] = gimp_preview_area_new ();
            gtk_widget_set_size_request (edit_previews[mut],
                                         EDIT_PREVIEW_SIZE,
                                         EDIT_PREVIEW_SIZE);
            button = gtk_button_new ();
            gtk_widget_set_hexpand (button, TRUE);
            gtk_widget_set_halign (button, GTK_ALIGN_CENTER);
            gtk_container_add (GTK_CONTAINER(button), edit_previews[mut]);
            gtk_grid_attach (GTK_GRID (grid), button, i, j, 1, 1);
            gtk_widget_show (edit_previews[mut]);

            gtk_widget_show (button);

            g_object_set_data (G_OBJECT (button), "config",  proc_config);
            g_signal_connect (button, "clicked",
                              G_CALLBACK (preview_clicked),
                              GINT_TO_POINTER (mut));
          }

      g_signal_connect (edit_previews[0], "size-allocate",
                        G_CALLBACK (edit_preview_size_allocate),
                        proc_config);

      frame = gimp_frame_new (_("Controls"));
      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);
      gtk_widget_show (vbox);

      scale = gimp_scale_entry_new (_("_Speed:"), pick_speed, 0.05, 0.5, 2);
      gimp_label_spin_set_increments (GIMP_LABEL_SPIN (scale), 0.01, 0.1);

      g_object_set_data (G_OBJECT (scale), "config",  proc_config);
      g_signal_connect (scale, "value-changed",
                        G_CALLBACK (flame_scale_entry_update_double),
                        &pick_speed);
      g_signal_connect_swapped (scale, "value-changed",
                                G_CALLBACK (set_edit_preview),
                                proc_config);
      gtk_box_pack_start (GTK_BOX (vbox), scale, FALSE, FALSE, 6);
      gtk_widget_show (scale);

      hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
      gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
      gtk_widget_show (hbox);

      button = gtk_button_new_with_mnemonic( _("_Randomize"));
      g_object_set (gtk_bin_get_child (GTK_BIN (button)),
                    "margin-start", 2,
                    "margin-end",   2,
                    NULL);
      gtk_box_pack_start (GTK_BOX (hbox), button, FALSE, FALSE, 0);
      gtk_widget_show (button);

      g_signal_connect_swapped (button, "clicked",
                                G_CALLBACK (randomize_callback),
                                proc_config);

      combo = gimp_int_combo_box_new (_("Same"),         VARIATION_SAME,
                                      _("Random"),       variation_random,
                                      _("Linear"),       0,
                                      _("Sinusoidal"),   1,
                                      _("Spherical"),    2,
                                      _("Swirl"),        3,
                                      _("Horseshoe"),    4,
                                      _("Polar"),        5,
                                      _("Bent"),         6,
                                      _("Handkerchief"), 7,
                                      _("Heart"),        8,
                                      _("Disc"),         9,
                                      _("Spiral"),       10,
                                      _("Hyperbolic"),   11,
                                      _("Diamond"),      12,
                                      _("Ex"),           13,
                                      _("Julia"),        14,
                                      _("Waves"),        15,
                                      _("Fisheye"),      16,
                                      _("Popcorn"),      17,
                                      _("Exponential"),  18,
                                      _("Power"),        19,
                                      _("Cosine"),       20,
                                      _("Rings"),        21,
                                      _("Fan"),          22,
                                      _("Eyefish"),      23,
                                      _("Bubble"),       24,
                                      _("Cylinder"),     25,
                                      _("Noise"),        26,
                                      _("Blur"),         27,
                                      _("Gaussian"),     28,
                                      NULL);

      gimp_int_combo_box_set_active (GIMP_INT_COMBO_BOX (combo),
                                     VARIATION_SAME);

      g_object_set_data (G_OBJECT (combo), "config",  proc_config);
      g_signal_connect (combo, "changed",
                        G_CALLBACK (combo_callback),
                        &config.variation);

      gtk_box_pack_end (GTK_BOX (hbox), combo, TRUE, TRUE, 0);
      gtk_widget_show (combo);

      label = gtk_label_new_with_mnemonic (_("_Variation:"));
      gtk_box_pack_end (GTK_BOX (hbox), label, FALSE, FALSE, 0);
      gtk_label_set_mnemonic_widget (GTK_LABEL (label), combo);
      gtk_widget_show (label);

      gtk_widget_show (main_vbox);

      init_mutants (proc_config);
    }

  set_edit_preview (proc_config);

  gtk_window_present (GTK_WINDOW (edit_dialog));
}

static void
load_callback (GtkWidget           *widget,
               GimpProcedureConfig *proc_config)
{
  if (! file_dialog)
    {
      load_save = 1;
      make_file_dialog (_("Load Flame"), gtk_widget_get_toplevel (widget), proc_config);

      gtk_widget_set_sensitive (save_button, FALSE);
    }

  gtk_window_present (GTK_WINDOW (file_dialog));
}

static void
save_callback (GtkWidget           *widget,
               GimpProcedureConfig *proc_config)
{
  if (! file_dialog)
    {
      load_save = 0;
      make_file_dialog (_("Save Flame"), gtk_widget_get_toplevel (widget), proc_config);

      gtk_widget_set_sensitive (load_button, FALSE);
    }

  gtk_window_present (GTK_WINDOW (file_dialog));
}

static void
combo_callback (GtkWidget *widget,
                gpointer   data)
{
  GimpProcedureConfig *proc_config;

  proc_config = g_object_get_data (G_OBJECT (widget), "config");

  gimp_int_combo_box_get_active (GIMP_INT_COMBO_BOX (widget), (gint *) data);

  if (VARIATION_SAME != config.variation)
    random_control_point (&edit_cp, config.variation);

  init_mutants (proc_config);
  set_edit_preview (proc_config);

  flame_update_settings_aux (proc_config);
}

static void
set_flame_preview (GimpProcedureConfig *proc_config)
{
  GBytes *settings_bytes = NULL;
  guchar *b;
  control_point pcp;

  static frame_spec pf = {0.0, 0, 1, 0.0};

  if (NULL == flame_preview)
    return;

  g_object_get (proc_config, "settings-data", &settings_bytes, NULL);
  if (settings_bytes != NULL)
    {
      if (g_bytes_get_size (settings_bytes) == sizeof (FlameSettings))
        config = *((FlameSettings *) g_bytes_get_data (settings_bytes, NULL));

      g_bytes_unref (settings_bytes);
    }

  g_object_get (proc_config,
                "x",                     &config.cp.center[0],
                "y",                     &config.cp.center[1],
                "spatial-oversample",    &config.cp.spatial_oversample,
                "gamma",                 &config.cp.gamma,
                "contrast",              &config.cp.contrast,
                "brightness",            &config.cp.brightness,
                "spatial-filter-radius", &config.cp.spatial_filter_radius,
                "sample-density",        &config.cp.sample_density,
                "zoom",                  &config.cp.zoom,
                NULL);

  b = g_new (guchar, preview_width * preview_height * 3);

  maybe_init_cp (proc_config);
  drawable_to_cmap (&config.cp);

  pf.cps = &pcp;
  pcp = config.cp;
  pcp.pixels_per_unit =
    (pcp.pixels_per_unit * preview_width) / pcp.width;
  pcp.width = preview_width;
  pcp.height = preview_height;
  pcp.sample_density = 1;
  pcp.spatial_oversample = 1;
  pcp.spatial_filter_radius = 0.1;
  render_rectangle (&pf, b, preview_width, field_both, 3, NULL);

  gimp_preview_area_draw (GIMP_PREVIEW_AREA (flame_preview),
                          0, 0, preview_width, PREVIEW_SIZE,
                          GIMP_RGB_IMAGE,
                          b,
                          preview_width * 3);
  g_free (b);
}

static void
flame_preview_size_allocate (GimpProcedureConfig *proc_config)
{
  set_flame_preview (proc_config);
}

static void
set_cmap_preview (void)
{
  gint i, x, y;
  guchar b[96];
  guchar *cmap_buffer, *ptr;

  if (NULL == cmap_preview)
    return;

  drawable_to_cmap (&config.cp);

  cmap_buffer = g_new (guchar, 32*32*3);
  ptr = cmap_buffer;
  for (y = 0; y < 32; y += 4)
    {
      for (x = 0; x < 32; x++)
        {
          gint j;

          i = x + (y/4) * 32;
          for (j = 0; j < 3; j++)
            b[x*3+j] = config.cp.cmap[i][j]*255.0;
        }

      memcpy (ptr, b, 32*3);
      ptr += 32*3;
      memcpy (ptr, b, 32*3);
      ptr += 32*3;
      memcpy (ptr, b, 32*3);
      ptr += 32*3;
      memcpy (ptr, b, 32*3);
      ptr += 32*3;
    }

  gimp_preview_area_draw (GIMP_PREVIEW_AREA (cmap_preview),
                          0, 0, 32, 32,
                          GIMP_RGB_IMAGE,
                          cmap_buffer,
                          32 * 3);
  g_free (cmap_buffer);
}

static void
cmap_callback (GtkWidget           *widget,
               GimpProcedureConfig *proc_config)
{
  gimp_int_combo_box_get_active (GIMP_INT_COMBO_BOX (widget),
                                 &config.cmap_drawable_id);

  g_signal_handlers_block_by_func (proc_config,
                                   G_CALLBACK (set_flame_preview),
                                   NULL);
  flame_update_settings_aux (proc_config);
  g_signal_handlers_unblock_by_func (proc_config,
                                     G_CALLBACK (set_flame_preview),
                                     NULL);

  set_cmap_preview ();
  set_flame_preview (proc_config);
  /* set_edit_preview(); */
}

static gboolean
cmap_constrain (GimpImage *image,
                GimpItem  *item,
                gpointer   data)
{
  return ! item || ! gimp_drawable_is_indexed (GIMP_DRAWABLE (item));
}


static gboolean
flame_dialog (Flame                *flame,
              GimpProcedure        *procedure,
              GimpProcedureConfig  *proc_config)
{
  GtkWidget *main_vbox;
  GtkWidget *notebook;
  GtkWidget *frame;
  GtkWidget *button;
  GtkWidget *box;
  gulong     notify_handler;
  gboolean   run;

  gimp_ui_init (PLUG_IN_BINARY);

  dialog = gimp_procedure_dialog_new (procedure, proc_config, _("Flame"));
  g_object_set_data (G_OBJECT (dialog), "config",  proc_config);

  main_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
  gtk_container_set_border_width (GTK_CONTAINER (main_vbox), 12);
  gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))),
                      main_vbox, FALSE, FALSE, 0);
  gtk_widget_show (main_vbox);

  box = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 12);
  gtk_box_pack_start (GTK_BOX (main_vbox), box, FALSE, FALSE, 0);
  gtk_widget_show (box);

  frame = gtk_frame_new (NULL);
  gtk_widget_set_valign (frame, GTK_ALIGN_START);
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_IN);
  gtk_box_pack_start (GTK_BOX (box), frame, FALSE, FALSE, 0);
  gtk_widget_show (frame);

  flame_preview = gimp_preview_area_new ();
    {
      gdouble aspect = config.cp.width / (double) config.cp.height;

      if (aspect > 1.0)
        {
          preview_width = PREVIEW_SIZE;
          preview_height = PREVIEW_SIZE / aspect;
        }
      else
        {
          preview_width = PREVIEW_SIZE * aspect;
          preview_height = PREVIEW_SIZE;
        }
    }
  gtk_widget_set_size_request (flame_preview, preview_width, preview_height);
  gtk_container_add (GTK_CONTAINER (frame), flame_preview);
  gtk_widget_show (flame_preview);
  g_signal_connect_swapped (flame_preview, "size-allocate",
                            G_CALLBACK (flame_preview_size_allocate),
                            proc_config);

    {
      GtkWidget *vbox;
      GtkWidget *vbbox;

      vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 6);
      gtk_box_pack_start (GTK_BOX (box), vbox, FALSE, FALSE, 0);
      gtk_widget_show (vbox);

      vbbox= gtk_button_box_new (GTK_ORIENTATION_VERTICAL);
      gtk_box_set_homogeneous (GTK_BOX (vbbox), FALSE);
      gtk_box_set_spacing (GTK_BOX (vbbox), 6);
      gtk_box_pack_start (GTK_BOX (vbox), vbbox, FALSE, FALSE, 0);
      gtk_widget_show (vbbox);

      button = gtk_button_new_with_mnemonic (_("_Edit"));
      gtk_box_pack_start (GTK_BOX (vbbox), button, FALSE, FALSE, 0);
      gtk_widget_show (button);

      g_signal_connect (button, "clicked",
                        G_CALLBACK (edit_callback),
                        dialog);

      load_button = button = gtk_button_new_with_mnemonic (_("_Open"));
      gtk_box_pack_start (GTK_BOX (vbbox), button, FALSE, FALSE, 0);
      gtk_widget_show (button);

      g_signal_connect (button, "clicked",
                        G_CALLBACK (load_callback),
                        proc_config);

      save_button = button = gtk_button_new_with_mnemonic (_("_Save"));
      gtk_box_pack_start (GTK_BOX (vbbox), button, FALSE, FALSE, 0);
      gtk_widget_show (button);

      g_signal_connect (button, "clicked",
                        G_CALLBACK (save_callback),
                        proc_config);
    }

  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "brightness", 1.0);
  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "contrast", 1.0);
  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "gamma", 1.0);
  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "sample-density", 1.0);
  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "spatial-oversample", 1.0);
  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "spatial-filter-radius", 1.0);
  box = gimp_procedure_dialog_fill_box (GIMP_PROCEDURE_DIALOG (dialog),
                                        "rendering-box",
                                        "brightness", "contrast", "gamma",
                                        "sample-density", "spatial-oversample",
                                        "spatial-filter-radius", NULL);

    {
      GtkWidget *hbox;
      GtkWidget *label;
      GtkWidget *combo;

      hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
      gtk_box_pack_start (GTK_BOX (box), hbox, FALSE, FALSE, 0);
      gtk_widget_show (hbox);

      label = gtk_label_new_with_mnemonic (_("Color_map:"));
      gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
      gtk_widget_show (label);

      combo = gimp_drawable_combo_box_new (cmap_constrain, NULL, NULL);

      gtk_label_set_mnemonic_widget (GTK_LABEL (label), combo);

#if 0
      gimp_int_combo_box_prepend (GIMP_INT_COMBO_BOX (combo),
                                  GIMP_INT_STORE_VALUE, BLACK_DRAWABLE,
                                  GIMP_INT_STORE_LABEL, _("Black"),
                                  -1);
#endif

        {
          static const gchar *names[] =
            {
              "sunny harvest",
              "rose",
              "calcoast09",
              "klee insula-dulcamara",
              "ernst anti-pope",
              "gris josette"
            };
          static const gint good[] = { 10, 20, 68, 79, 70, 75 };

          gint i;

          for (i = 0; i < G_N_ELEMENTS (good); i++)
            {
              gint value = TABLE_DRAWABLE - good[i];

              gimp_int_combo_box_prepend (GIMP_INT_COMBO_BOX (combo),
                                          GIMP_INT_STORE_VALUE, value,
                                          GIMP_INT_STORE_LABEL, names[i],
                                          -1);
            }
        }

      gimp_int_combo_box_prepend (GIMP_INT_COMBO_BOX (combo),
                                  GIMP_INT_STORE_VALUE,     GRADIENT_DRAWABLE,
                                  GIMP_INT_STORE_LABEL,     _("Custom gradient"),
                                  GIMP_INT_STORE_ICON_NAME, GIMP_ICON_GRADIENT,
                                  -1);

      gimp_int_combo_box_connect (GIMP_INT_COMBO_BOX (combo),
                                  config.cmap_drawable_id,
                                  G_CALLBACK (cmap_callback),
                                  proc_config, NULL);

      gtk_box_pack_start (GTK_BOX (hbox), combo, TRUE, TRUE, 0);
      gtk_widget_show (combo);

      cmap_preview = gimp_preview_area_new ();
      gtk_widget_set_size_request (cmap_preview, 32, 32);

      gtk_box_pack_end (GTK_BOX (hbox), cmap_preview, FALSE, FALSE, 0);
      gtk_widget_show (cmap_preview);

      set_cmap_preview ();
    }

  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "zoom", 1.0);
  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "x", 1.0);
  gimp_procedure_dialog_get_spin_scale (GIMP_PROCEDURE_DIALOG (dialog), "y", 1.0);
  gimp_procedure_dialog_fill_box (GIMP_PROCEDURE_DIALOG (dialog),
                                  "camera-box", "zoom", "x", "y", NULL);

  gimp_procedure_dialog_get_label (GIMP_PROCEDURE_DIALOG (dialog),
                                   "rendering-label", _("_Rendering"),
                                   FALSE, TRUE);
  gimp_procedure_dialog_get_label (GIMP_PROCEDURE_DIALOG (dialog),
                                   "camera-label", _("C_amera"),
                                   FALSE, TRUE);
  notebook = gimp_procedure_dialog_fill_notebook (GIMP_PROCEDURE_DIALOG (dialog),
                                                  "settings-notebook",
                                                  "rendering-label", "rendering-box",
                                                  "camera-label",    "camera-box",
                                                  NULL);
  gtk_widget_show (notebook);
  gtk_box_pack_start (GTK_BOX (main_vbox), notebook, FALSE, FALSE, 0);

  notify_handler = g_signal_connect (proc_config, "notify",
                                     G_CALLBACK (set_flame_preview),
                                     NULL);
  set_flame_preview (proc_config);
  run = gimp_procedure_dialog_run (GIMP_PROCEDURE_DIALOG (dialog));

  g_signal_handler_disconnect (proc_config, notify_handler);
  gtk_widget_destroy (dialog);

  return run;
}

static void
flame_scale_entry_update_double (GimpLabelSpin *entry,
                                 gdouble       *value)
{
  GimpProcedureConfig *proc_config;

  proc_config = g_object_get_data (G_OBJECT (entry), "config");

  *value = gimp_label_spin_get_value (entry);

  flame_update_settings_aux (proc_config);
}

static void
flame_update_settings_aux (GimpProcedureConfig *proc_config)
{
  GBytes *settings_bytes;

  settings_bytes = g_bytes_new (&config, sizeof (FlameSettings));
  g_object_set (proc_config, "settings-data", settings_bytes, NULL);
  g_bytes_unref (settings_bytes);
}