2.99 ScriptFu: add custom widgets to GimpProcedureDialog

For version 3 scripts, using script-fu-register-filter

Widgets for SF-OPTION and SF-DIRNAME

Fixes #9992

Test case is Sphere v3.

Note that SF-VECTORS is still not supported,
until there is a VectorsChooser widget in libgimp.

A step towards deprecating old-style scripts using script-fu-register,
and deleting script-fu-interface, the duplicate dialog for SF.
But we still need to change or replace script-fu-register (for non-filter plugins)
to use GimpProcedureDialog.

plug-ins/script-fu/libscriptfu/meson.build

@@ -21,6 +21,7 @@ libscriptfu_sources = [
   'script-fu-dialog.c',
   'script-fu-run-func.c',
   'script-fu-command.c',
+  'script-fu-widgets-custom.c',
 ]
 
 # !! just "library(...)" which means shared versus static depends on configuration of project.

plug-ins/script-fu/libscriptfu/script-fu-arg.c

@@ -91,6 +91,7 @@ void
 script_fu_arg_free (SFArg *arg)
 {
   g_free (arg->label);
+  g_free (arg->property_name);
 
   switch (arg->type)
     {
@@ -386,6 +387,10 @@ script_fu_arg_get_param_spec (SFArg       *arg,
       /* FUTURE: Default not now appear in PDB browser, but appears in widgets? */
       break;
 
+      /* Not necessary to have a more specific pspec:
+       * pspec = gimp_param_spec_config_path (...GIMP_TYPE_CONFIG_PATH...)
+       */
+
     case SF_ENUM:
       /* history is the last used value AND the default. */
       pspec = g_param_spec_enum (name,
@@ -695,6 +700,8 @@ script_fu_arg_reset_name_generator (void)
  * The returned string is owned by the generator, a constant.
  * The caller need not copy it,
  * but usually does by creating a GParamSpec.
+ *
+ * As a side effect, a copy of the string is kept in arg->property_name.
  */
 void
 script_fu_arg_generate_name_and_nick (SFArg        *arg,
@@ -803,6 +810,9 @@ script_fu_arg_generate_name_and_nick (SFArg        *arg,
 
   arg_count[arg->type]++;
 
+  /* Side effect: remember the generated name. */
+  arg->property_name = g_strdup (numbered_name);
+
   *returned_name = numbered_name;
 
   /* nick is what the script author said describes the arg */

plug-ins/script-fu/libscriptfu/script-fu-dialog.c

@@ -27,6 +27,7 @@
 #include "script-fu-command.h"
 
 #include "script-fu-dialog.h"
+#include "script-fu-widgets-custom.h"
 
 
 /* An informal class that shows a dialog for a script then runs the script.
@@ -159,13 +160,11 @@ script_fu_dialog_run (GimpProcedure        *procedure,
                                       script_fu_script_get_title (script));
   /* dialog has no widgets except standard buttons. */
 
-  /* It is possible to create custom widget where the provided widget is not adequate.
-   * Then gimp_procedure_dialog_fill_list will create the rest.
-   * For now, the provided widgets should be adequate.
-   */
+  /* Create custom widget where the stock widget is not adequate. */
+  script_fu_widgets_custom_add (dialog, script);
 
   /* NULL means create widgets for all properties of the procedure
-   * that we have not already created widgets for.
+   * that we have not already created custom widgets for.
    */
   gimp_procedure_dialog_fill_list (dialog, NULL);
 

plug-ins/script-fu/libscriptfu/script-fu-types.h

@@ -73,7 +73,8 @@ typedef union
 typedef struct
 {
   SFArgType   type;
-  gchar      *label;
+  gchar      *label;         /* label on widget in dialog. Not unique. */
+  gchar      *property_name; /* name of property of Procedure. Unique. */
   SFArgValue  default_value;
   SFArgValue  value;
 } SFArg;

plug-ins/script-fu/libscriptfu/script-fu-widgets-custom.c

@@ -0,0 +1,200 @@
+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * Copyright (C) 2024 Lloyd Konneker
+ *
+ * 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 <libgimp/gimpui.h>
+
+#include "script-fu-types.h"
+#include "script-fu-widgets-custom.h"
+
+/* Widgets in GimpProcedureDialog *custom* to ScriptFu.
+ *
+ * GimpProcedureDialog provides stock widgets
+ * based on the type of a procedure argument.
+ * A custom widget is the same kind of widget as stock, but specialized.
+ *
+ * Both stock and custom widgets are keyed to a property name
+ * of the GimpProcedure for the script.
+ * You add custom widgets, then call gimp_procedure_dialog_fill_list()
+ * which adds a stock widget for any property name not having a custom widget.
+ *
+ * FUTURE: implement these in GimpProcedureDialog.
+ * That can't be done now because GParamSpecs are limited
+ * in the types they can describe.
+ * E.G. SF-OPTION describes an enumerated type
+ * that can't be described completely in a GParamSpec.
+ * E.G. property type GFile is a general type
+ * whose subtypes: existing-file, existing-dir, or file-to-save
+ * can't be described in a GParamSpec.
+ *
+ * Most SFArg types are supported by stock widgets.
+ *
+ * SF-FILENAME is stock.
+ * For property of type G_TYPE_FILE.
+ * A GtkFileChooser in the mode for user to open a existing file.
+ *
+ * SF-DIRNAME is custom.
+ * Also a GtkFileChooser but in mode for user to choose a directory.
+ *
+ * FUTURE:
+ * SF-SAVE-FILENAME is custom.
+ * Also a GtkFileChooser but in mode for user to save a file
+ * (choose a file to replace, or enter filename and choose a directory.)
+ *
+ * SF-OPTION is custom.
+ * Is an int combo box widget, for an enumeration defined by the script
+ * (versus SF-ENUM for enums defined by GIMP.)
+ * Note SF-OPTION does not create symbols in the interpreter.
+ * The script itself, and all other plugins, must use integer literals
+ * to denote values.
+ */
+
+/* Does SFArg type need custom widget? */
+static gboolean
+sf_arg_type_is_custom (SFScript *script,
+                       guint     arg_index)
+{
+  switch (script->args[arg_index].type)
+    {
+    case SF_DIRNAME:
+    case SF_OPTION:
+      return TRUE;
+    default:
+      return FALSE;
+    }
+}
+
+/* Returns new GtkListStore from SFArg declaration.
+ * Transfers ownership of the allocated, returned store.
+ * Ownership transfers to a dialog, which frees it on dialog destroy.
+ *
+ * Returned value is never NULL.
+ * Returned store can be empty if the declaration of the arg is non-sensical.
+ */
+static GtkListStore *
+sf_widget_custom_new_int_store (SFArg *arg)
+{
+  GtkListStore *result;
+  GSList       *list;
+  guint         counter = 0; /* SF enumerations start at 0. */
+
+  /* Create empty store. */
+  result = g_object_new (GIMP_TYPE_INT_STORE, NULL);
+
+  /* Iterate over list of names of enumerated values,
+   * appending each to store having value equal to the iteration index.
+   *
+   * ScriptFu does NOT define constant Scheme symbols in the interpreter;
+   * the names of enumerated values are not available to the script,
+   * which must use integer literals or (define other symbols for the values.)
+   */
+  for (list = arg->default_value.sfa_option.list;
+       list;
+       list = g_slist_next (list))
+    {
+      GtkTreeIter iter;
+
+      gtk_list_store_append (result, &iter);
+      gtk_list_store_set (result, &iter,
+                          GIMP_INT_STORE_VALUE, counter,
+                          GIMP_INT_STORE_LABEL, list->data,
+                          -1);
+      counter++;
+    }
+
+  return result;
+}
+
+/* Adds widget for arg of type SF-OPTION to the dialog.
+ * Widget is a combobox widget.
+ * Specializes the widget by a custom store i.e. model
+ * derived from the arg's declaration.
+ */
+static void
+sf_widget_custom_option (GimpProcedureDialog *dialog,
+                         SFArg               *arg)
+{
+  GtkListStore *store;
+
+  store = sf_widget_custom_new_int_store (arg);
+  gimp_procedure_dialog_get_int_combo (dialog,
+                                       arg->property_name,
+                                       GIMP_INT_STORE (store));
+}
+
+/* Adds widget for arg of type SF-DIRNAME to the dialog.
+ * Widget is a GtkFileChooserButton.
+ * Specializes the widget to be in mode for user to choose a directory.
+ *
+ * Note that this is implemented by gtk_file_chooser_button,
+ * which does not support ACTION_SAVE, and which becomes obsolete in Gtk4.
+ * Thus, we don't have SF-SAVE-FILENAME.
+ * To offer save, a script must use two widgets:
+ * SF-STRING for user to name a file to save,
+ * and SF-DIRNAME for user to choose directory to save to.
+ */
+static void
+sf_widget_custom_dirname (GimpProcedureDialog *dialog,
+                         SFArg                *arg)
+{
+  gimp_procedure_dialog_get_file_chooser (dialog,
+                                          arg->property_name,
+                                          GTK_FILE_CHOOSER_ACTION_SELECT_FOLDER);
+}
+
+/* Add a custom widget for a script's arg to the script's dialog.
+ * Does nothing when the type of the arg does not need a custom widget.
+ *
+ * Widget is associated with the arg's property, by name of the property.
+ * The arg's property is a property of the Procedure.
+ * The widget will be positioned in the dialog by order of property.
+ */
+static void
+sf_widget_custom_add_to_dialog (GimpProcedureDialog *dialog,
+                                SFArg               *arg)
+{
+  /* Handles same cases as sf_arg_type_is_custom() */
+  switch (arg->type)
+    {
+    case SF_OPTION:
+      sf_widget_custom_option (dialog, arg);
+      break;
+    case SF_DIRNAME:
+      sf_widget_custom_dirname (dialog, arg);
+      break;
+    default:
+      break;
+    }
+}
+
+
+/* Add custom widgets to dialog, for certain type of args of script. */
+void
+script_fu_widgets_custom_add (GimpProcedureDialog *dialog,
+                              SFScript            *script)
+{
+  for (int arg_index=0; arg_index < script->n_args; arg_index++)
+    {
+      if (sf_arg_type_is_custom (script, arg_index))
+        {
+          sf_widget_custom_add_to_dialog (dialog, &script->args[arg_index]);
+        }
+    }
+}

plug-ins/script-fu/libscriptfu/script-fu-widgets-custom.h

@@ -0,0 +1,26 @@
+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * Copyright (C) 2024 Lloyd Konneker
+ *
+ * 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/>.
+ */
+
+#ifndef __SCRIPT_FU_WIDGETS_CUSTOM_H__
+#define __SCRIPT_FU_WIDGETS_CUSTOM_H__
+
+void    script_fu_widgets_custom_add (GimpProcedureDialog *dialog,
+                                      SFScript            *script);
+
+#endif /* __SCRIPT_FU_WIDGETS_CUSTOM_H__ */

plug-ins/script-fu/scripts/test-sphere-v3.scm

@@ -30,7 +30,7 @@
                                size
                                unused-palette
                                unused-filename
-                               unused-orientation
+                               orientation
                                unused-interpolation
                                unused-dirname
                                unused-image
@@ -123,6 +123,9 @@
                                                        size
                                                        font)))
 
+    (if (= orientation 1)
+      (gimp-image-rotate img ROTATE-DEGREES90))
+
     (gimp-image-undo-enable img)
     (gimp-display-new img)