/* The GIMP -- an image manipulation program * Copyright (C) 1995-1999 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. * * Undo history browser by Austin Donnelly */ /* TODO: * * - reuse the L&C previews? * Currently we use gimp_image_construct_composite_preview () * which makes use of the preview_cache on a per layer basis. * * - work out which (if any) is the clean image, and mark it as such. * Currently, it's on the wrong line. * * - undo names are less than useful. This isn't a problem with * undo_history.c itself, more with the rather chaotic way * people have of picking an undo type when pushing undos, and * inconsistent use of undo groups. Maybe rather than * specifying an (enum) type, it should be a const char * ? * * BUGS: * - clean pixmap in wrong place * * Initial rev 0.01, (c) 19 Sept 1999 Austin Donnelly * */ #include "config.h" #include #include "libgimpwidgets/gimpwidgets.h" #include "apptypes.h" #include "paint-funcs/paint-funcs.h" #include "dialog_handler.h" #include "gimage_mask.h" #include "gimpdrawable.h" #include "gimpimage.h" #include "gimprc.h" #include "pixel_region.h" #include "temp_buf.h" #include "undo.h" #include "libgimp/gimplimits.h" #include "libgimp/gimpintl.h" #include "pixmaps/raise.xpm" #include "pixmaps/lower.xpm" #include "pixmaps/yes.xpm" #include "pixmaps/question.xpm" typedef struct { GimpImage *gimage; /* image we're tracking undo info for */ GtkWidget *shell; /* dialog window */ GtkWidget *clist; /* list of undo actions */ GtkWidget *undo_button; /* button to undo an operation */ GtkWidget *redo_button; /* button to redo an operation */ int old_selection; /* previous selection in the clist */ int preview_size; /* size of the previews (from preferences) */ } undo_history_st; typedef struct { GtkCList *clist; gint row; gint size; GimpImage *gimage; } idle_preview_args; /* * Theory of operation. * * Keep a clist. Each row of the clist corresponds to an image as it * was at some time in the past, present or future. The selected row * is the present image. Rows below the selected one are in the * future - as redo operations are performed, they become the current * image. Rows above the selected one are in the past - undo * operations move the highlight up. * * The slight fly in the ointment is that if rows are images, then how * should they be labelled? An undo or redo operation goes _between_ * two image states - it isn't an image state. It's a pretty * arbitrary decision, but I've chosen to label a row with the name of * the action that brought the image into the state represented by * that row. Thus, there is a special first row without a meaningful * label, which represents the image state before the first action has * been done to it. The choice is between a special first row or a * special last row. Since people mostly work near the leading edge, * not often going all the way back, I've chosen to put the special * case out of common sight. * * So, the undo stack contents appear above the selected row, and the * redo stack below it. * * The clist is initialised by mapping over the undo and redo stack. * * Once initialised, the dialog listens to undo_event signals from the * gimage. These undo events allow us to track changes to the undo * and redo stacks. We follow the events, making parallel changes to * the clist. If we ever get out of sync, there is no mechanism to * notice or re-sync. A few g_return_if_fails should catch some of * these cases. * * User clicks changing the selected row in the clist turn into * multiple calls to undo_pop or undo_redo, with appropriate signals * blocked so we don't get our own events back. * * The "Close" button hides the dialog, rather than destroying it. * This may well need to be changed, since the dialog will continue to * track updates, and if it's generating previews this might take too * long for large images. * * The dialog is destroyed when the gimage it is tracking is * destroyed. Note that a File/Revert destroys the current gimage and * so blows the undo/redo stacks. * * --austin, 19/9/1999 */ /**************************************************************/ /* Static Data */ static GdkPixmap *clean_pixmap = NULL; static GdkBitmap *clean_mask = NULL; static GdkPixmap *clear_pixmap = NULL; static GdkBitmap *clear_mask = NULL; /**************************************************************/ /* Local functions */ static MaskBuf * mask_render_preview (GimpImage *gimage, gint *pwidth, gint *pheight) { GimpChannel *mask; MaskBuf *scaled_buf = NULL; PixelRegion srcPR, destPR; gint subsample; gint width, height; gint scale; mask = gimp_image_get_mask (gimage); if ((gimp_drawable_width (GIMP_DRAWABLE(mask)) > *pwidth) || (gimp_drawable_height (GIMP_DRAWABLE(mask)) > *pheight)) { if (((gfloat) gimp_drawable_width (GIMP_DRAWABLE (mask)) / (gfloat) *pwidth) > ((gfloat) gimp_drawable_height (GIMP_DRAWABLE (mask)) / (gfloat) *pheight)) { width = *pwidth; height = (gimp_drawable_height (GIMP_DRAWABLE (mask)) * (*pwidth)) / gimp_drawable_width (GIMP_DRAWABLE (mask)); } else { width = (gimp_drawable_width (GIMP_DRAWABLE (mask)) * (*pheight)) / gimp_drawable_height (GIMP_DRAWABLE (mask)); height = *pheight; } scale = TRUE; } else { width = gimp_drawable_width (GIMP_DRAWABLE (mask)); height = gimp_drawable_height (GIMP_DRAWABLE (mask)); scale = FALSE; } /* if the mask is empty, no need to scale and update again */ if (gimage_mask_is_empty (gimage)) return NULL; if (scale) { /* calculate 'acceptable' subsample */ subsample = 1; while ((width * (subsample + 1) * 2 < gimp_drawable_width (GIMP_DRAWABLE (mask))) && (height * (subsample + 1) * 2 < gimp_drawable_height (GIMP_DRAWABLE (mask)))) subsample = subsample + 1; pixel_region_init (&srcPR, gimp_drawable_data (GIMP_DRAWABLE (mask)), 0, 0, gimp_drawable_width (GIMP_DRAWABLE (mask)), gimp_drawable_height (GIMP_DRAWABLE (mask)), FALSE); scaled_buf = mask_buf_new (width, height); destPR.bytes = 1; destPR.x = 0; destPR.y = 0; destPR.w = width; destPR.h = height; destPR.rowstride = srcPR.bytes * width; destPR.data = mask_buf_data (scaled_buf); destPR.tiles = NULL; subsample_region (&srcPR, &destPR, subsample); } else { pixel_region_init (&srcPR, gimp_drawable_data (GIMP_DRAWABLE (mask)), 0, 0, gimp_drawable_width (GIMP_DRAWABLE (mask)), gimp_drawable_height (GIMP_DRAWABLE (mask)), FALSE); scaled_buf = mask_buf_new (width, height); destPR.bytes = 1; destPR.x = 0; destPR.y = 0; destPR.w = width; destPR.h = height; destPR.rowstride = srcPR.bytes * width; destPR.data = mask_buf_data (scaled_buf); destPR.tiles = NULL; copy_region (&srcPR, &destPR); } *pheight = height; *pwidth = width; return scaled_buf; } static gint undo_history_set_pixmap_idle (gpointer data) { idle_preview_args *idle = data; static GdkGC *gc = NULL; TempBuf *buf = NULL; GdkPixmap *pixmap; UndoType utype; MaskBuf *mbuf = NULL; guchar *src; gdouble r, g, b, a; gdouble c0, c1; guchar *p0, *p1, *even, *odd; gint width, height, bpp; gint x, y; if (!gc) gc = gdk_gc_new (GTK_WIDGET (idle->clist)->window); width = idle->gimage->width; height = idle->gimage->height; /* Get right aspect ratio */ if (width > height) { height = (gint)(((gdouble)idle->size * (gdouble)height) / (gdouble)width + 0.5); width = (gint)(((gdouble)width * (gdouble)height)/ (gdouble)idle->gimage->height + 0.5); } else { width = (gint)(((gdouble)idle->size * (gdouble)width) / (gdouble)height + 0.5); height = (gint)(((gdouble)height * (gdouble)width ) /(gdouble) idle->gimage->width + 0.5); } utype = undo_get_undo_top_type (idle->gimage); if ((utype != MASK_UNDO && utype != QMASK_UNDO) || (mbuf = mask_render_preview (idle->gimage, &width, &height)) == NULL) { buf = gimp_viewable_get_new_preview (GIMP_VIEWABLE (idle->gimage), width, height); bpp = buf->bytes; src = temp_buf_data (buf); } else { src = mask_buf_data (mbuf); bpp = 1; /* Always the case for masks */ } pixmap = gdk_pixmap_new (GTK_WIDGET (idle->clist)->window, width + 2, height + 2, -1); gdk_draw_rectangle (pixmap, GTK_WIDGET (idle->clist)->style->black_gc, TRUE, 0, 0, width + 2, height + 2); even = g_malloc (width * 3); odd = g_malloc (width * 3); for (y = 0; y < height; y++) { p0 = even; p1 = odd; for (x = 0; x < width; x++) { if (bpp == 4) { r = ((gdouble) src[x*4+0]) / 255.0; g = ((gdouble) src[x*4+1]) / 255.0; b = ((gdouble) src[x*4+2]) / 255.0; a = ((gdouble) src[x*4+3]) / 255.0; } else if (bpp == 3) { r = ((gdouble) src[x*3+0]) / 255.0; g = ((gdouble) src[x*3+1]) / 255.0; b = ((gdouble) src[x*3+2]) / 255.0; a = 1.0; } else { r = ((gdouble) src[x*bpp+0]) / 255.0; g = b = r; if (bpp == 2) a = ((gdouble) src[x*bpp+1]) / 255.0; else a = 1.0; } if ((x / GIMP_CHECK_SIZE_SM) & 1) { c0 = GIMP_CHECK_LIGHT; c1 = GIMP_CHECK_DARK; } else { c0 = GIMP_CHECK_DARK; c1 = GIMP_CHECK_LIGHT; } *p0++ = (c0 + (r - c0) * a) * 255.0; *p0++ = (c0 + (g - c0) * a) * 255.0; *p0++ = (c0 + (b - c0) * a) * 255.0; *p1++ = (c1 + (r - c1) * a) * 255.0; *p1++ = (c1 + (g - c1) * a) * 255.0; *p1++ = (c1 + (b - c1) * a) * 255.0; } if ((y / GIMP_CHECK_SIZE_SM) & 1) { gdk_draw_rgb_image (pixmap, gc, 1, y + 1, width, 1, GDK_RGB_DITHER_NORMAL, (guchar *) odd, 3); } else { gdk_draw_rgb_image (pixmap, gc, 1, y + 1, width, 1, GDK_RGB_DITHER_NORMAL, (guchar *) even, 3); } src += width * bpp; } g_free (even); g_free (odd); if (buf) temp_buf_free (buf); if (mbuf) mask_buf_free (mbuf); gtk_clist_set_row_data (idle->clist, idle->row, (gpointer)2); gtk_clist_set_pixmap (idle->clist, idle->row, 0, pixmap, NULL); gdk_pixmap_unref (pixmap); return (FALSE); } /* check if a preview is already made, otherwise gtk_idle_add the pixmap func */ static void undo_history_set_pixmap (GtkCList *clist, gint row, gint size, GimpImage *gimage) { static idle_preview_args idle; if (!size || ((gint)gtk_clist_get_row_data (clist, row)) == 2) return; idle.clist = clist; idle.row = row; idle.size = size; idle.gimage = gimage; gtk_idle_add ((GtkFunction)undo_history_set_pixmap_idle, &idle); } /* close button clicked */ static void undo_history_close_callback (GtkWidget *widget, gpointer data) { undo_history_st *st = data; gtk_widget_hide (GTK_WIDGET (st->shell)); } /* The gimage and shell destroy callbacks are split so we can: * a) blow the shell when the image dissappears * b) disconnect from the image if the shell dissappears (we don't * want signals from the image to carry on using "st" once it's * been freed. */ /* gimage renamed */ static void undo_history_gimage_rename_callback (GimpImage *gimage, gpointer data) { undo_history_st *st = data; gchar *title; title = g_strdup_printf (_("Undo History: %s"), g_basename (gimp_image_filename (gimage))); gtk_window_set_title (GTK_WINDOW (st->shell), title); g_free (title); } /* gimage destroyed */ static void undo_history_gimage_destroy_callback (GimpImage *gimage, gpointer data) { undo_history_st *st = data; st->gimage = NULL; /* not allowed to use this any more */ dialog_unregister (st->shell); gtk_widget_destroy (GTK_WIDGET (st->shell)); /* which continues in the function below: */ } static void undo_history_shell_destroy_callback (GtkWidget *widget, gpointer data) { undo_history_st *st = data; if (st->gimage) gtk_signal_disconnect_by_data (GTK_OBJECT (st->gimage), st); g_free (st); } /* undo button clicked */ static void undo_history_undo_callback (GtkWidget *widget, gpointer data) { undo_history_st *st = data; undo_pop (st->gimage); } /* redo button clicked */ static void undo_history_redo_callback (GtkWidget *widget, gpointer data) { undo_history_st *st = data; undo_redo (st->gimage); } /* Always start clist with dummy entry for image state before * the first action on the undo stack */ static void undo_history_prepend_special (GtkCList *clist) { gchar *name = _("[ base image ]"); gchar *namelist[3]; gint row; namelist[0] = NULL; namelist[1] = NULL; namelist[2] = name; row = gtk_clist_prepend (clist, namelist); } /* Recalculate which of the undo and redo buttons are meant to be sensitive */ static void undo_history_set_sensitive (undo_history_st *st, gint rows) { gtk_widget_set_sensitive (st->undo_button, (st->old_selection != 0)); gtk_widget_set_sensitive (st->redo_button, (st->old_selection != rows-1)); } /* Track undo_event signals, telling us of changes to the undo and * redo stacks. */ static void undo_history_undo_event (GtkWidget *widget, gint ev, gpointer data) { undo_history_st *st = data; undo_event_t event = ev; const gchar *name; gchar *namelist[3]; GList *list; gint cur_selection; GtkCList *clist; gint row; GdkPixmap *pixmap; GdkBitmap *mask; list = GTK_CLIST (st->clist)->selection; g_return_if_fail (list != NULL); cur_selection = GPOINTER_TO_INT (list->data); clist = GTK_CLIST (st->clist); /* block select events */ gtk_signal_handler_block_by_data (GTK_OBJECT (st->clist), st); switch (event) { case UNDO_PUSHED: /* clip everything after the current selection (ie, the * actions that are from the redo stack) */ gtk_clist_freeze (clist); while (clist->rows > cur_selection + 1) gtk_clist_remove (clist, cur_selection + 1); /* find out what's new */ name = undo_get_undo_name (st->gimage); namelist[0] = NULL; namelist[1] = NULL; namelist[2] = (char *) name; row = gtk_clist_append (clist, namelist); g_assert (clist->rows == cur_selection + 2); undo_history_set_pixmap (clist, row, st->preview_size, st->gimage); /* always force selection to bottom, and scroll to it */ gtk_clist_select_row (clist, clist->rows - 1, -1); gtk_clist_thaw (clist); gtk_clist_moveto (clist, clist->rows - 1, 0, 1.0, 0.0); cur_selection = clist->rows - 1; break; case UNDO_EXPIRED: /* remove earliest row, but not our special first one */ if (gtk_clist_get_pixmap (clist, 1, 0, &pixmap, &mask)) gtk_clist_set_pixmap (clist, 0, 0, pixmap, mask); gtk_clist_remove (clist, 1); break; case UNDO_POPPED: /* move hilight up one */ g_return_if_fail (cur_selection >= 1); gtk_clist_select_row (clist, cur_selection - 1, -1); cur_selection--; undo_history_set_pixmap (clist, cur_selection, st->preview_size, st->gimage); if ( !(gtk_clist_row_is_visible (clist, cur_selection) & GTK_VISIBILITY_FULL)) gtk_clist_moveto (clist, cur_selection, 0, 0.0, 0.0); break; case UNDO_REDO: /* move hilight down one */ g_return_if_fail (cur_selection+1 < clist->rows); gtk_clist_select_row (clist, cur_selection+1, -1); cur_selection++; undo_history_set_pixmap (clist, cur_selection, st->preview_size, st->gimage); if ( !(gtk_clist_row_is_visible (clist, cur_selection) & GTK_VISIBILITY_FULL)) gtk_clist_moveto (clist, cur_selection, 0, 1.0, 0.0); break; case UNDO_FREE: /* clear all info other that the special first line */ gtk_clist_freeze (clist); gtk_clist_clear (clist); undo_history_prepend_special (clist); gtk_clist_thaw (clist); cur_selection = 0; break; } /* if the image is clean, set the clean pixmap */ if (st->gimage->dirty == 0) gtk_clist_set_pixmap (clist, cur_selection, 1, clean_pixmap, clean_mask); gtk_signal_handler_unblock_by_data (GTK_OBJECT (st->clist), st); st->old_selection = cur_selection; undo_history_set_sensitive (st, clist->rows); } static void undo_history_select_row_callback (GtkWidget *widget, gint row, gint column, gpointer event, gpointer data) { undo_history_st *st = data; gint cur_selection; cur_selection = row; if (cur_selection == st->old_selection) return; /* Disable undo_event signals while we do these multiple undo or * redo actions. */ gtk_signal_handler_block_by_func (GTK_OBJECT (st->gimage), undo_history_undo_event, st); while (cur_selection < st->old_selection) { undo_pop (st->gimage); st->old_selection--; } while (cur_selection > st->old_selection) { undo_redo (st->gimage); st->old_selection++; } undo_history_set_pixmap (GTK_CLIST (widget), cur_selection, st->preview_size, st->gimage); /* if the image is clean, set the clean pixmap */ if (st->gimage->dirty == 0) gtk_clist_set_pixmap (GTK_CLIST (widget), cur_selection, 1, clean_pixmap, clean_mask); gtk_signal_handler_unblock_by_func (GTK_OBJECT (st->gimage), undo_history_undo_event, st); undo_history_set_sensitive (st, GTK_CLIST(st->clist)->rows); } static void undo_history_clean_callback (GtkWidget *widget, gpointer data) { undo_history_st *st = data; gint i; gint nrows; GtkCList *clist; if (st->gimage->dirty != 0) return; /* * The image has become clean. Remove the clean_pixmap from * all entries. It will be set in the undo_event or select_row * callbacks. * Ugly, but works better than before. The actual problem is * that the "clean" signal is emitted before UNDO_POPPED event, * so we can not simply set the clean pixmap here. */ clist = GTK_CLIST (st->clist); nrows = clist->rows; gtk_clist_freeze (clist); for (i=0; i < nrows; i++) gtk_clist_set_text (clist, i, 1, NULL); gtk_clist_thaw (clist); } /* Used to build up initial contents of clist */ static gboolean undo_history_init_undo (const gchar *undoitemname, void *data) { undo_history_st *st = data; gchar *namelist[3]; gint row; namelist[0] = NULL; namelist[1] = NULL; namelist[2] = (gchar *) undoitemname; row = gtk_clist_prepend (GTK_CLIST (st->clist), namelist); gtk_clist_set_pixmap (GTK_CLIST (st->clist), row, 0, clear_pixmap, clear_mask); return FALSE; } /* Ditto */ static gboolean undo_history_init_redo (const char *undoitemname, void *data) { undo_history_st *st = data; gchar *namelist[3]; gint row; namelist[0] = NULL; namelist[1] = NULL; namelist[2] = (gchar *) undoitemname; row = gtk_clist_append (GTK_CLIST (st->clist), namelist); gtk_clist_set_pixmap (GTK_CLIST (st->clist), row, 0, clear_pixmap, clear_mask); return FALSE; } /*************************************************************/ /* Publicly exported function */ GtkWidget * undo_history_new (GimpImage *gimage) { undo_history_st *st; GtkWidget *vbox; GtkWidget *hbox; GtkWidget *button; GtkWidget *scrolled_win; st = g_new0 (undo_history_st, 1); st->gimage = gimage; st->preview_size = preview_size; /* gimage signals */ gtk_signal_connect (GTK_OBJECT (gimage), "undo_event", GTK_SIGNAL_FUNC (undo_history_undo_event), st); gtk_signal_connect (GTK_OBJECT (gimage), "name_changed", GTK_SIGNAL_FUNC (undo_history_gimage_rename_callback), st); gtk_signal_connect (GTK_OBJECT (gimage), "destroy", GTK_SIGNAL_FUNC (undo_history_gimage_destroy_callback), st); gtk_signal_connect (GTK_OBJECT (gimage), "clean", GTK_SIGNAL_FUNC (undo_history_clean_callback), st); /* The shell and main vbox */ { gchar *title = g_strdup_printf (_("Undo History: %s"), g_basename (gimp_image_filename (gimage))); st->shell = gimp_dialog_new (title, "undo_history", gimp_standard_help_func, "dialogs/undo_history.html", GTK_WIN_POS_NONE, FALSE, TRUE, FALSE, _("Close"), undo_history_close_callback, st, NULL, NULL, TRUE, TRUE, NULL); dialog_register (st->shell); g_free (title); } vbox = gtk_vbox_new (FALSE, 2); gtk_container_set_border_width (GTK_CONTAINER (vbox), 2); gtk_container_add (GTK_CONTAINER (GTK_DIALOG (st->shell)->vbox), vbox); gtk_widget_show (vbox); gtk_signal_connect (GTK_OBJECT (st->shell), "destroy", GTK_SIGNAL_FUNC (undo_history_shell_destroy_callback), st); scrolled_win = gtk_scrolled_window_new (NULL, NULL); gtk_widget_set_usize (GTK_WIDGET (scrolled_win), 160 + st->preview_size, 4 * (MAX (st->preview_size, 16) + 6)); /* clist of undo actions */ st->clist = gtk_clist_new (3); gtk_clist_set_selection_mode (GTK_CLIST (st->clist), GTK_SELECTION_BROWSE); gtk_clist_set_reorderable (GTK_CLIST (st->clist), FALSE); gtk_clist_set_row_height (GTK_CLIST (st->clist), MAX (st->preview_size, 16) + 4); gtk_clist_set_column_width (GTK_CLIST (st->clist), 0, st->preview_size + 2); gtk_clist_set_column_width (GTK_CLIST (st->clist), 1, 18); gtk_clist_set_column_min_width (GTK_CLIST (st->clist), 2, 64); /* allocate the pixmaps if not already done */ if (!clean_pixmap) { GtkStyle *style; gtk_widget_realize (st->shell); style = gtk_widget_get_style (st->shell); clean_pixmap = gdk_pixmap_create_from_xpm_d (st->shell->window, &clean_mask, &style->bg[GTK_STATE_NORMAL], yes_xpm); clear_pixmap = gdk_pixmap_create_from_xpm_d (st->shell->window, &clear_mask, &style->bg[GTK_STATE_NORMAL], question_xpm); } /* work out the initial contents */ undo_map_over_undo_stack (st->gimage, undo_history_init_undo, st); /* force selection to bottom */ gtk_clist_select_row (GTK_CLIST (st->clist), GTK_CLIST (st->clist)->rows - 1, -1); undo_map_over_redo_stack (st->gimage, undo_history_init_redo, st); undo_history_prepend_special (GTK_CLIST (st->clist)); st->old_selection = GPOINTER_TO_INT(GTK_CLIST(st->clist)->selection->data); /* draw the preview of the current state */ undo_history_set_pixmap (GTK_CLIST (st->clist), st->old_selection, st->preview_size, st->gimage); gtk_signal_connect (GTK_OBJECT (st->clist), "select_row", GTK_SIGNAL_FUNC (undo_history_select_row_callback), st); /* if the image is clean, set the clean pixmap */ if (st->gimage->dirty == 0) gtk_clist_set_pixmap (GTK_CLIST (st->clist), st->old_selection, 1, clean_pixmap, clean_mask); gtk_widget_show (GTK_WIDGET (st->clist)); gtk_box_pack_start (GTK_BOX (vbox), scrolled_win, TRUE, TRUE, 0); gtk_widget_show (GTK_WIDGET (scrolled_win)); gtk_container_add (GTK_CONTAINER (scrolled_win), st->clist); gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (scrolled_win), GTK_POLICY_NEVER, GTK_POLICY_ALWAYS); hbox = gtk_hbox_new (FALSE, 6); gtk_container_set_border_width (GTK_CONTAINER (hbox), 2); gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0); gtk_widget_show (hbox); st->undo_button = button = gimp_pixmap_button_new (raise_xpm, _("Undo")); gtk_box_pack_start (GTK_BOX (hbox), button, TRUE, TRUE, 0); gtk_signal_connect (GTK_OBJECT (button), "clicked", GTK_SIGNAL_FUNC (undo_history_undo_callback), st); gtk_widget_show (GTK_WIDGET (button)); st->redo_button = button = gimp_pixmap_button_new (lower_xpm, _("Redo")); gtk_box_pack_start (GTK_BOX (hbox), button, TRUE, TRUE, 0); gtk_signal_connect (GTK_OBJECT (button), "clicked", GTK_SIGNAL_FUNC (undo_history_redo_callback), st); gtk_widget_show (GTK_WIDGET (button)); undo_history_set_sensitive (st, GTK_CLIST (st->clist)->rows); gtk_widget_show (GTK_WIDGET (st->shell)); gtk_clist_moveto (GTK_CLIST (st->clist), st->old_selection, 0, 0.5, 0.0); return st->shell; }