Fix for 390458 : Convert Export Bitmap to a dockable dialog

(bzr r11042)

1 files changed, 1825 insertions, 0 deletions

diff --git a/src/ui/dialog/export.cpp b/src/ui/dialog/export.cpp
new file mode 100644
index 000000000..150abd66b
--- /dev/null
+++ b/src/ui/dialog/export.cpp
@@ -0,0 +1,1825 @@
+/**
+ * @file
+ * PNG export dialog.
+ */
+/* Authors:
+ *   Lauris Kaplinski <lauris@kaplinski.com>
+ *   bulia byak <buliabyak@users.sf.net>
+ *   Johan Engelen <j.b.c.engelen@ewi.utwente.nl>
+ *   Jon A. Cruz <jon@joncruz.org>
+ *   Abhishek Sharma
+ *
+ * Copyright (C) 1999-2007 Authors
+ * Copyright (C) 2001-2002 Ximian, Inc.
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+// This has to be included prior to anything that includes setjmp.h, it croaks otherwise
+#include <png.h>
+
+#include <gtkmm/box.h>
+#include <gtkmm/buttonbox.h>
+#include <gtkmm/label.h>
+#include <gtkmm/widget.h>
+#include <gtkmm/togglebutton.h>
+#include <gtkmm/entry.h>
+#include <gtkmm/image.h>
+#include <gtkmm/stockid.h>
+#include <gtkmm/stock.h>
+#include <gtkmm/table.h>
+#ifdef WITH_GNOME_VFS
+# include <libgnomevfs/gnome-vfs-init.h>  // gnome_vfs_initialized
+#endif
+
+#include <glibmm/i18n.h>
+#include "helper/unit-menu.h"
+#include "helper/units.h"
+#include "unit-constants.h"
+#include "helper/window.h"
+#include "inkscape-private.h"
+#include "document.h"
+#include "document-undo.h"
+#include "desktop-handles.h"
+#include "sp-item.h"
+#include "selection.h"
+#include "file.h"
+#include "macros.h"
+#include "sp-namedview.h"
+#include "selection-chemistry.h"
+
+#include "dialogs/dialog-events.h"
+#include "preferences.h"
+#include "verbs.h"
+#include "interface.h"
+#include "sp-root.h"
+
+#include "extension/output.h"
+#include "extension/db.h"
+
+#include "io/sys.h"
+
+#include "helper/png-write.h"
+
+#ifdef WIN32
+#include <windows.h>
+#include <commdlg.h>
+#include <gdk/gdkwin32.h>
+#endif
+
+#include <gtk/gtk.h>
+
+#define SP_EXPORT_MIN_SIZE 1.0
+
+#define DPI_BASE PX_PER_IN
+
+#define EXPORT_COORD_PRECISION 3
+
+#include "../../desktop-handles.h"
+#include "../../document.h"
+#include "../../document-undo.h"
+#include "verbs.h"
+#include "export.h"
+
+
+namespace Inkscape {
+namespace UI {
+namespace Dialog {
+
+Export::Export (void) :
+    UI::Widget::Panel ("", "/dialogs/export/", SP_VERB_DIALOG_EXPORT),
+    current_key(SELECTION_PAGE),
+    original_name(NULL),
+    doc_export_name(NULL),
+    filename_modified(false),
+    was_empty(true),
+    update(false),
+    togglebox(true, 0),
+    area_box(false, 3),
+    singleexport_box(false, 0),
+    size_box(false, 3),
+    file_box(false, 3),
+    unitbox(false, 0),
+    units_label(_("Units:")),
+    filename_box(false, 5),
+    browse_label(_("_Browse..."), 1),
+    browse_image(Gtk::StockID(Gtk::Stock::INDEX), Gtk::ICON_SIZE_BUTTON),
+    batch_box(false, 5),
+    batch_export(_("B_atch export all selected objects"), _("Export each selected object into its own PNG file, using export hints if any (caution, overwrites without asking!)")),
+    hide_box(false, 5),
+    hide_export(_("Hide a_ll except selected"), _("In the exported image, hide all objects except those that are selected")),
+    button_box(Gtk::BUTTONBOX_END),
+    export_label(_("_Export"), 1),
+    export_image(Gtk::StockID(Gtk::Stock::APPLY), Gtk::ICON_SIZE_BUTTON),
+    prefs(NULL),
+    desktop(NULL),
+    deskTrack(),
+    selectChangedConn(),
+    subselChangedConn(),
+    selectModifiedConn()
+{
+    prefs = Inkscape::Preferences::get();
+
+    singleexport_box.set_border_width(0);
+
+    /* Export area frame */
+    {
+
+    #if WITH_GTKMM_2_22
+        Gtk::Label* lbl = new Gtk::Label(_("<big><b>Export area</b></big>"), Gtk::ALIGN_START);
+    #else
+        Gtk::Label* lbl = new Gtk::Label(_("<big><b>Export area</b></big>"), Gtk::ALIGN_LEFT);
+    #endif
+        lbl->set_use_markup(true);
+        area_box.pack_start(*lbl);
+
+        /* Units box */
+        /* gets added to the vbox later, but the unit selector is needed
+           earlier than that */
+        unit_selector = Glib::wrap(sp_unit_selector_new (SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE));
+        SPDesktop *desktop = SP_ACTIVE_DESKTOP;
+        if (desktop)
+            sp_unit_selector_set_unit (SP_UNIT_SELECTOR(unit_selector->gobj()), sp_desktop_namedview(desktop)->doc_units);
+        unitbox.pack_end(*unit_selector, false, false, 0);
+        unitbox.pack_end(units_label, false, false, 3);
+
+        for (int i = 0; i < SELECTION_NUMBER_OF; i++) {
+            selectiontype_buttons[i] = new Gtk::RadioButton(_(selection_labels[i]), true);
+            if (i > 0) {
+                Gtk::RadioButton::Group group = selectiontype_buttons[0]->get_group();
+                selectiontype_buttons[i]->set_group(group);
+            }
+            selectiontype_buttons[i]->set_mode(false);
+            togglebox.pack_start(*selectiontype_buttons[i], false, true, 0);
+            selectiontype_buttons[i]->signal_clicked().connect(sigc::mem_fun(*this, &Export::onAreaToggled));
+        }
+
+        Gtk::Table* t = new Gtk::Table(2, 6, false);
+        t->set_row_spacings (4);
+        t->set_col_spacings (4);
+
+        x0_adj = createSpinbutton ( "x0", 0.0, -1000000.0, 1000000.0, 0.1, 1.0, unit_selector->gobj(),
+                                   GTK_WIDGET(t->gobj()), 0, 0, _("_x0:"), NULL, EXPORT_COORD_PRECISION, 1,
+                                   &Export::onAreaX0Change);
+
+        x1_adj = createSpinbutton ( "x1", 0.0, -1000000.0, 1000000.0, 0.1, 1.0, unit_selector->gobj(),
+                                   GTK_WIDGET(t->gobj()), 2, 0, _("x_1:"), NULL, EXPORT_COORD_PRECISION, 1,
+                                   &Export::onAreaX1Change);
+
+        width_adj = createSpinbutton ( "width", 0.0, 0.0, PNG_UINT_31_MAX, 0.1, 1.0,
+                                   unit_selector->gobj(), GTK_WIDGET(t->gobj()), 4, 0, _("Wid_th:"), NULL, EXPORT_COORD_PRECISION, 1,
+                                   &Export::onAreaWidthChange);
+
+        y0_adj = createSpinbutton ( "y0", 0.0, -1000000.0, 1000000.0, 0.1, 1.0, unit_selector->gobj(),
+                                   GTK_WIDGET(t->gobj()), 0, 1, _("_y0:"), NULL, EXPORT_COORD_PRECISION, 1,
+                                   &Export::onAreaY0Change);
+
+        y1_adj = createSpinbutton ( "y1", 0.0, -1000000.0, 1000000.0, 0.1, 1.0, unit_selector->gobj(),
+                                   GTK_WIDGET(t->gobj()), 2, 1, _("y_1:"), NULL, EXPORT_COORD_PRECISION, 1,
+                                   &Export::onAreaY1Change);
+
+        height_adj = createSpinbutton ( "height", 0.0, 0.0, PNG_UINT_31_MAX, 0.1, 1.0,
+                                   unit_selector->gobj(), GTK_WIDGET(t->gobj()), 4, 1, _("Hei_ght:"), NULL, EXPORT_COORD_PRECISION, 1,
+                                   &Export::onAreaHeightChange);
+
+        area_box.pack_start(togglebox, false, false, 3);
+        area_box.pack_start(*t, false, false, 0);
+        area_box.pack_start(unitbox, false, false, 0);
+
+        area_box.set_border_width(3);
+        singleexport_box.pack_start(area_box, false, false, 0);
+
+    } // end of area box
+
+    /* Bitmap size frame */
+    {
+        size_box.set_border_width(3);
+
+#if WITH_GTKMM_2_22
+        bm_label = new Gtk::Label(_("<big><b>Bitmap size</b></big>"), Gtk::ALIGN_START);
+#else
+        bm_label = new Gtk::Label(_("<big><b>Bitmap size</b></big>"), Gtk::ALIGN_LEFT);
+#endif
+        bm_label->set_use_markup(true);
+        size_box.pack_start(*bm_label, false, false, 0);
+        Gtk::Table *t = new Gtk::Table(2, 5, false);
+        t->set_row_spacings (4);
+        t->set_col_spacings (4);
+        size_box.pack_start(*t);
+
+        bmwidth_adj = createSpinbutton ( "bmwidth", 16.0, 1.0, 1000000.0, 1.0, 10.0,
+                                   NULL, GTK_WIDGET(t->gobj()), 0, 0,
+                                   _("_Width:"), _("pixels at"), 0, 1,
+                                   &Export::onBitmapWidthChange);
+
+        xdpi_adj = createSpinbutton ( "xdpi",
+                                   prefs->getDouble("/dialogs/export/defaultxdpi/value", DPI_BASE),
+                                   0.01, 100000.0, 0.1, 1.0, NULL, GTK_WIDGET(t->gobj()), 3, 0,
+                                   NULL, _("dp_i"), 2, 1,
+                                   &Export::onExportXdpiChange);
+
+        bmheight_adj = createSpinbutton ( "bmheight", 16.0, 1.0, 1000000.0, 1.0, 10.0,
+                                   NULL, GTK_WIDGET(t->gobj()), 0, 1,
+                                   _("_Height:"), _("pixels at"), 0, 1,
+                                   &Export::onBitmapHeightChange);
+
+        /** TODO
+         *  There's no way to set ydpi currently, so we use the defaultxdpi value here, too...
+         */
+        ydpi_adj = createSpinbutton ( "ydpi", prefs->getDouble("/dialogs/export/defaultxdpi/value", DPI_BASE),
+                                   0.01, 100000.0, 0.1, 1.0, NULL, GTK_WIDGET(t->gobj()), 3, 1,
+                                   NULL, _("dpi"), 2, 0, NULL );
+
+        singleexport_box.pack_start(size_box);
+    }
+
+    /* File entry */
+    {
+        file_box.set_border_width(3);
+
+#if WITH_GTKMM_2_22
+        flabel = new Gtk::Label(_("<big><b>_Filename</b></big>"), Gtk::ALIGN_START, Gtk::ALIGN_CENTER, true);
+#else
+        flabel = new Gtk::Label(_("<big><b>_Filename</b></big>"), Gtk::ALIGN_LEFT, Gtk::ALIGN_CENTER, true);
+#endif
+        flabel->set_use_markup(true);
+        file_box.pack_start(*flabel, false, false, 0);
+
+        set_default_filename();
+
+        filename_box.pack_start (filename_entry, true, true, 0);
+
+        Gtk::HBox* browser_im_label = new Gtk::HBox(false, 3);
+        browser_im_label->pack_start(browse_image);
+        browser_im_label->pack_start(browse_label);
+        browse_button.add(*browser_im_label);
+        filename_box.pack_end (browse_button, false, false, 4);
+
+        file_box.add(filename_box);
+
+        original_name = g_strdup(filename_entry.get_text().c_str());
+
+        // focus is in the filename initially:
+        filename_entry.grab_focus();
+
+        // mnemonic in frame label moves focus to filename:
+        flabel->set_mnemonic_widget(filename_entry);
+
+        singleexport_box.pack_start(file_box);
+    }
+
+    batch_export.set_sensitive(true);
+    batch_box.pack_start(batch_export, false, false);
+
+    hide_export.set_sensitive(true);
+    hide_box.pack_start(hide_export, false, false);
+
+    /* Export Button row */
+    button_box.set_border_width(3);
+    Gtk::HBox* export_image_label = new Gtk::HBox(false, 3);
+    export_image_label->pack_start(export_image);
+    export_image_label->pack_start(export_label);
+
+    export_button.add(*export_image_label);
+    export_button.set_tooltip_text (_("Export the bitmap file with these settings"));
+    button_box.pack_end(export_button, false, false, 0);
+
+
+    /* Main dialog */
+    Gtk::Box *contents = _getContents();
+    contents->set_spacing(0);
+    contents->pack_start(singleexport_box);
+    contents->pack_start(batch_box);
+    contents->pack_start(hide_box);
+    contents->pack_end(button_box, false, false, 0);
+
+    /* Signal handlers */
+    filename_entry.signal_changed().connect( sigc::mem_fun(*this, &Export::onFilenameModified) );
+    // pressing enter in the filename field is the same as clicking export:
+    filename_entry.signal_activate().connect(sigc::mem_fun(*this, &Export::onExport) );
+    browse_button.signal_clicked().connect(sigc::mem_fun(*this, &Export::onBrowse));
+    batch_export.signal_clicked().connect(sigc::mem_fun(*this, &Export::onBatchClicked));
+    export_button.signal_clicked().connect(sigc::mem_fun(*this, &Export::onExport));
+
+    desktopChangeConn = deskTrack.connectDesktopChanged( sigc::mem_fun(*this, &Export::setTargetDesktop) );
+    deskTrack.connect(GTK_WIDGET(gobj()));
+
+    show_all_children();
+
+    findDefaultSelection();
+    onAreaToggled();
+}
+
+Export::~Export (void)
+{
+    g_free(original_name);
+    original_name = NULL;
+    g_free(doc_export_name);
+    doc_export_name = NULL;
+    was_empty = TRUE;
+
+    selectModifiedConn.disconnect();
+    subselChangedConn.disconnect();
+    selectChangedConn.disconnect();
+    desktopChangeConn.disconnect();
+    deskTrack.disconnect();
+}
+
+void Export::setDesktop(SPDesktop *desktop)
+{
+    Panel::setDesktop(desktop);
+    deskTrack.setBase(desktop);
+}
+
+void Export::setTargetDesktop(SPDesktop *desktop)
+{
+    if (this->desktop != desktop) {
+        if (this->desktop) {
+            selectModifiedConn.disconnect();
+            subselChangedConn.disconnect();
+            selectChangedConn.disconnect();
+        }
+        this->desktop = desktop;
+        if (desktop && desktop->selection) {
+
+            selectChangedConn = desktop->selection->connectChanged(sigc::hide(sigc::mem_fun(*this, &Export::onSelectionChanged)));
+            subselChangedConn = desktop->connectToolSubselectionChanged(sigc::hide(sigc::mem_fun(*this, &Export::onSelectionChanged)));
+
+            //// Must check flags, so can't call widget_setup() directly.
+            selectModifiedConn = desktop->selection->connectModified(sigc::hide<0>(sigc::mem_fun(*this, &Export::onSelectioModified)));
+        }
+        //widget_setup();
+    }
+}
+
+/*
+ * set the default filename to be that of the current path + document
+ * with .png extension
+ *
+ * One thing to notice here is that this filename may get
+ * overwritten, but it won't happen here.  The filename gets
+ * written into the text field, but then the button to select
+ * the area gets set.  In that code the filename can be changed
+ * if there are some with presidence in the document.  So, while
+ * this code sets the name first, it may not be the one users
+ * really see.
+ */
+void Export::set_default_filename () {
+
+    if ( SP_ACTIVE_DOCUMENT && SP_ACTIVE_DOCUMENT->getURI() )
+    {
+        gchar *name;
+        SPDocument * doc = SP_ACTIVE_DOCUMENT;
+        const gchar *uri = doc->getURI();
+        const gchar *text_extension = get_file_save_extension (Inkscape::Extension::FILE_SAVE_METHOD_SAVE_AS).c_str();
+        Inkscape::Extension::Output * oextension = NULL;
+
+        if (text_extension != NULL) {
+            oextension = dynamic_cast<Inkscape::Extension::Output *>(Inkscape::Extension::db.get(text_extension));
+        }
+
+        if (oextension != NULL) {
+            gchar * old_extension = oextension->get_extension();
+            if (g_str_has_suffix(uri, old_extension)) {
+                gchar * uri_copy;
+                gchar * extension_point;
+                gchar * final_name;
+
+                uri_copy = g_strdup(uri);
+                extension_point = g_strrstr(uri_copy, old_extension);
+                extension_point[0] = '\0';
+
+                final_name = g_strconcat(uri_copy, ".png", NULL);
+                filename_entry.set_text(final_name);
+
+                g_free(final_name);
+                g_free(uri_copy);
+            }
+        } else {
+            name = g_strconcat(uri, ".png", NULL);
+            filename_entry.set_text(name);
+            g_free(name);
+        }
+
+        doc_export_name = g_strdup(filename_entry.get_text().c_str());
+    }
+
+}
+
+/**
+ * Creates a new spin button for the export dialog.
+ * @param  key  The name of the spin button
+ * @param  val  A default value for the spin button
+ * @param  min  Minimum value for the spin button
+ * @param  max  Maximum value for the spin button
+ * @param  step The step size for the spin button
+ * @param  page Size of the page increment
+ * @param  us   Unit selector that effects this spin button
+ * @param  t    Table to put the spin button in
+ * @param  x    X location in the table \c t to start with
+ * @param  y    Y location in the table \c t to start with
+ * @param  ll   Text to put on the left side of the spin button (optional)
+ * @param  lr   Text to put on the right side of the spin button (optional)
+ * @param  digits  Number of digits to display after the decimal
+ * @param  sensitive  Whether the spin button is sensitive or not
+ * @param  cb   Callback for when this spin button is changed (optional)
+ */
+Gtk::Adjustment * Export::createSpinbutton( gchar const *key, float val, float min, float max,
+                                      float step, float page, GtkWidget *us,
+                                      GtkWidget *t, int x, int y,
+                                      const gchar *ll, const gchar *lr,
+                                      int digits, unsigned int sensitive,
+                                      void (Export::*cb)() )
+{
+    Gtk::Adjustment *adj = new Gtk::Adjustment  ( val, min, max, step, page, 0 );
+
+    if (us) {
+        sp_unit_selector_add_adjustment ( SP_UNIT_SELECTOR (us),
+                                          GTK_ADJUSTMENT (adj->gobj()) );
+    }
+
+    int pos = 0;
+
+    GtkWidget *l = NULL;
+
+    if (ll) {
+
+        l = gtk_label_new_with_mnemonic ((const gchar *)ll);
+        gtk_misc_set_alignment (GTK_MISC (l), 1.0, 0.5);
+        gtk_table_attach ( GTK_TABLE (t), l, x + pos, x + pos + 1, y, y + 1,
+                           (GtkAttachOptions)0, (GtkAttachOptions)0, 0, 0 );
+        gtk_widget_set_sensitive (l, sensitive);
+        pos += 1;
+
+    }
+
+    GtkWidget *sb = gtk_spin_button_new (GTK_ADJUSTMENT (adj->gobj()), 1.0, digits);
+    gtk_table_attach ( GTK_TABLE (t), sb, x + pos, x + pos + 1, y, y + 1,
+                       (GtkAttachOptions)0, (GtkAttachOptions)0, 0, 0 );
+    gtk_widget_set_size_request (sb, 80, -1);
+    gtk_widget_set_sensitive (sb, sensitive);
+    pos += 1;
+
+    if (ll) { gtk_label_set_mnemonic_widget (GTK_LABEL(l), sb); }
+
+    if (lr) {
+
+        l = gtk_label_new_with_mnemonic ((const gchar *)lr);
+        gtk_misc_set_alignment (GTK_MISC (l), 0.0, 0.5);
+        gtk_table_attach ( GTK_TABLE (t), l, x + pos, x + pos + 1, y, y + 1,
+                           (GtkAttachOptions)0, (GtkAttachOptions)0, 0, 0 );
+        gtk_widget_set_sensitive (l, sensitive);
+        pos += 1;
+
+        gtk_label_set_mnemonic_widget (GTK_LABEL(l), sb);
+    }
+
+    if (cb) {
+        adj->signal_value_changed().connect( sigc::mem_fun(*this, cb) );
+    }
+
+    return adj;
+} // end of createSpinbutton()
+
+
+gchar* Export::create_filepath_from_id (const gchar *id, const gchar *file_entry_text) {
+
+    if (id == NULL) /* This should never happen */
+        id = "bitmap";
+
+    gchar *directory = NULL;
+
+    if (directory == NULL && file_entry_text != NULL && file_entry_text[0] != '\0') {
+        // std::cout << "Directory from dialog" << std::endl;
+        directory = g_path_get_dirname(file_entry_text);
+    }
+
+    if (directory == NULL) {
+        /* Grab document directory */
+        if ( SP_ACTIVE_DOCUMENT->getURI() ) {
+            // std::cout << "Directory from document" << std::endl;
+            directory = g_path_get_dirname( SP_ACTIVE_DOCUMENT->getURI() );
+        }
+    }
+
+    if (directory == NULL) {
+        // std::cout << "Home Directory" << std::endl;
+        directory = homedir_path(NULL);
+    }
+
+    gchar * id_ext = g_strconcat(id, ".png", NULL);
+    gchar *filename = g_build_filename(directory, id_ext, NULL);
+    g_free(directory);
+    g_free(id_ext);
+    return filename;
+}
+
+void
+Export::onBatchClicked ()
+{
+    if (batch_export.get_active()) {
+        singleexport_box.set_sensitive(false);
+    } else {
+        singleexport_box.set_sensitive(true);
+    }
+}
+
+void Export::updateCheckbuttons ()
+{
+    gint num = g_slist_length((GSList *) sp_desktop_selection(SP_ACTIVE_DESKTOP)->itemList());
+    if (num >= 2) {
+        batch_export.set_sensitive(true);
+        batch_export.set_label(g_strdup_printf (ngettext("B_atch export %d selected object","B_atch export %d selected objects",num), num));
+    } else {
+        batch_export.set_active (false);
+        batch_export.set_sensitive(false);
+    }
+    if (num > 0) {
+        hide_export.set_sensitive(true);
+    } else {
+        hide_export.set_sensitive(false);
+    }
+}
+
+inline void
+Export::findDefaultSelection()
+{
+    selection_type key = SELECTION_NUMBER_OF;
+
+    if ((sp_desktop_selection(SP_ACTIVE_DESKTOP))->isEmpty() == false) {
+        key = SELECTION_SELECTION;
+    }
+
+    /* Try using the preferences */
+    if (key == SELECTION_NUMBER_OF) {
+
+        int i = SELECTION_NUMBER_OF;
+
+        Glib::ustring what = prefs->getString("/dialogs/export/exportarea/value");
+
+        if (!what.empty()) {
+            for (i = 0; i < SELECTION_NUMBER_OF; i++) {
+                if (what == selection_names[i]) {
+                    break;
+                }
+            }
+        }
+
+        key = (selection_type)i;
+    }
+
+    if (key == SELECTION_NUMBER_OF) {
+        key = SELECTION_SELECTION;
+    }
+
+    current_key = key;
+    selectiontype_buttons[current_key]->set_active(true);
+    updateCheckbuttons ();
+}
+
+
+/**
+ * If selection changed or a different document activated, we must
+ * recalculate any chosen areas.
+ */
+void Export::onSelectionChanged()
+{
+    Inkscape::Selection *selection = sp_desktop_selection (SP_ACTIVE_DESKTOP);
+
+    if ((current_key == SELECTION_DRAWING || current_key == SELECTION_PAGE) &&
+            (sp_desktop_selection(SP_ACTIVE_DESKTOP))->isEmpty() == false &&
+            was_empty) {
+        current_key = SELECTION_SELECTION;
+        selectiontype_buttons[current_key]->set_active(true);
+    }
+    was_empty = (sp_desktop_selection(SP_ACTIVE_DESKTOP))->isEmpty();
+
+    if ( selection &&
+            SELECTION_CUSTOM != current_key) {
+        onAreaToggled();
+    }
+
+    updateCheckbuttons ();
+}
+
+void Export::onSelectioModified ( guint flags )
+{
+    switch (current_key) {
+        case SELECTION_DRAWING:
+            if ( SP_ACTIVE_DESKTOP ) {
+                SPDocument *doc;
+                doc = sp_desktop_document (SP_ACTIVE_DESKTOP);
+                Geom::OptRect bbox = doc->getRoot()->desktopVisualBounds();
+                if (bbox) {
+                    setArea ( bbox->left(),
+                                              bbox->top(),
+                                              bbox->right(),
+                                              bbox->bottom());
+                }
+            }
+            break;
+        case SELECTION_SELECTION:
+            if ((sp_desktop_selection(SP_ACTIVE_DESKTOP))->isEmpty() == false) {
+                Geom::OptRect bbox = (sp_desktop_selection (SP_ACTIVE_DESKTOP))->visualBounds();
+                setArea ( bbox->left(),
+                                          bbox->top(),
+                                          bbox->right(),
+                                          bbox->bottom());
+            }
+            break;
+        default:
+            /* Do nothing for page or for custom */
+            break;
+    }
+
+    return;
+}
+
+/// Called when one of the selection buttons was toggled.
+void Export::onAreaToggled ()
+{
+    if (update) {
+        return;
+    }
+
+    /* Find which button is active */
+    selection_type key = current_key;
+    for (int i = 0; i < SELECTION_NUMBER_OF; i++) {
+        if (selectiontype_buttons[i]->get_active()) {
+            key = (selection_type)i;
+        }
+    }
+
+    if ( SP_ACTIVE_DESKTOP )
+    {
+        SPDocument *doc;
+        Geom::OptRect bbox;
+        bbox = Geom::Rect(Geom::Point(0.0, 0.0),Geom::Point(0.0, 0.0));
+        doc = sp_desktop_document (SP_ACTIVE_DESKTOP);
+
+        /* Notice how the switch is used to 'fall through' here to get
+           various backups.  If you modify this without noticing you'll
+           probabaly screw something up. */
+        switch (key) {
+            case SELECTION_SELECTION:
+                if ((sp_desktop_selection(SP_ACTIVE_DESKTOP))->isEmpty() == false)
+                {
+                    bbox = sp_desktop_selection (SP_ACTIVE_DESKTOP)->visualBounds();
+                    /* Only if there is a selection that we can set
+                       do we break, otherwise we fall through to the
+                       drawing */
+                    // std::cout << "Using selection: SELECTION" << std::endl;
+                    key = SELECTION_SELECTION;
+                    break;
+                }
+            case SELECTION_DRAWING:
+                /** \todo
+                 * This returns wrong values if the document has a viewBox.
+                 */
+                bbox = doc->getRoot()->desktopVisualBounds();
+                /* If the drawing is valid, then we'll use it and break
+                   otherwise we drop through to the page settings */
+                if (bbox) {
+                    // std::cout << "Using selection: DRAWING" << std::endl;
+                    key = SELECTION_DRAWING;
+                    break;
+                }
+            case SELECTION_PAGE:
+                bbox = Geom::Rect(Geom::Point(0.0, 0.0),
+                                  Geom::Point(doc->getWidth(), doc->getHeight()));
+
+                // std::cout << "Using selection: PAGE" << std::endl;
+                key = SELECTION_PAGE;
+                break;
+            case SELECTION_CUSTOM:
+            default:
+                break;
+        } // switch
+
+        current_key = key;
+
+        // remember area setting
+        prefs->setString("/dialogs/export/exportarea/value", selection_names[current_key]);
+
+        if ( key != SELECTION_CUSTOM && bbox ) {
+            setArea ( bbox->min()[Geom::X],
+                                      bbox->min()[Geom::Y],
+                                      bbox->max()[Geom::X],
+                                      bbox->max()[Geom::Y]);
+        }
+
+    } // end of if ( SP_ACTIVE_DESKTOP )
+
+    if (SP_ACTIVE_DESKTOP && !filename_modified) {
+
+        const gchar * filename = NULL;
+        float xdpi = 0.0, ydpi = 0.0;
+
+        switch (key) {
+            case SELECTION_PAGE:
+            case SELECTION_DRAWING: {
+                SPDocument * doc = SP_ACTIVE_DOCUMENT;
+                sp_document_get_export_hints (doc, &filename, &xdpi, &ydpi);
+
+                if (filename == NULL) {
+                    if (doc_export_name != NULL) {
+                        filename = g_strdup(doc_export_name);
+                    } else {
+                        filename = g_strdup("");
+                    }
+                }
+                break;
+            }
+            case SELECTION_SELECTION:
+                if ((sp_desktop_selection(SP_ACTIVE_DESKTOP))->isEmpty() == false) {
+
+                    sp_selection_get_export_hints (sp_desktop_selection(SP_ACTIVE_DESKTOP), &filename, &xdpi, &ydpi);
+
+                    /* If we still don't have a filename -- let's build
+                       one that's nice */
+                    if (filename == NULL) {
+                        const gchar * id = NULL;
+                        const GSList * reprlst = sp_desktop_selection(SP_ACTIVE_DESKTOP)->reprList();
+                        for(; reprlst != NULL; reprlst = reprlst->next) {
+                            Inkscape::XML::Node * repr = (Inkscape::XML::Node *)reprlst->data;
+                            if (repr->attribute("id")) {
+                                id = repr->attribute("id");
+                                break;
+                            }
+                        }
+
+                        filename = create_filepath_from_id (id, filename_entry.get_text().c_str());
+                    }
+                }
+                break;
+            case SELECTION_CUSTOM:
+            default:
+                break;
+        }
+
+        if (filename != NULL) {
+            g_free(original_name);
+            original_name = g_strdup(filename);
+            filename_entry.set_text(filename);
+        }
+
+        if (xdpi != 0.0) {
+            setValue(xdpi_adj, xdpi);
+        }
+
+        /* These can't be separate, and setting x sets y, so for
+           now setting this is disabled.  Hopefully it won't be in
+           the future */
+        if (FALSE && ydpi != 0.0) {
+            setValue(ydpi_adj, ydpi);
+        }
+    }
+
+    return;
+} // end of sp_export_area_toggled()
+
+/// Called when dialog is deleted
+
+gint Export::onProgressDelete ( GtkWidget *widget, GdkEvent *event, GObject *base )
+{
+    g_object_set_data (base, "cancel", (gpointer) 1);
+    return TRUE;
+} // end of sp_export_progress_delete()
+
+
+/// Called when progress is cancelled
+void Export::onProgressCancel ( GtkWidget *widget, GObject *base )
+{
+    g_object_set_data (base, "cancel", (gpointer) 1);
+} // end of sp_export_progress_cancel()
+
+
+/// Called for every progress iteration
+unsigned int Export::onProgressCallback (float value, void *data)
+{
+    GtkWidget *prg;
+    int evtcount;
+
+    if (g_object_get_data ((GObject *) data, "cancel"))
+        return FALSE;
+
+    prg = (GtkWidget *) g_object_get_data ((GObject *) data, "progress");
+    gtk_progress_bar_set_fraction ((GtkProgressBar *) prg, value);
+
+    evtcount = 0;
+    while ((evtcount < 16) && gdk_events_pending ()) {
+            gtk_main_iteration_do (FALSE);
+            evtcount += 1;
+    }
+
+    gtk_main_iteration_do (FALSE);
+
+    return TRUE;
+
+} // end of sp_export_progress_callback()
+
+GtkWidget * Export::create_progress_dialog (gchar *progress_text) {
+
+    GtkWidget *dlg, *prg, *btn; /* progressbar dlg widgets */
+
+    dlg = gtk_dialog_new ();
+
+    GtkObject *base  = GTK_OBJECT(dlg);
+
+    gtk_window_set_title (GTK_WINDOW (dlg), _("Export in progress"));
+    prg = gtk_progress_bar_new ();
+    //sp_transientize (dlg);
+    gtk_window_set_resizable (GTK_WINDOW (dlg), FALSE);
+    g_object_set_data ((GObject *) base, "progress", prg);
+
+    gtk_progress_bar_set_text ((GtkProgressBar *) prg, progress_text);
+
+    gtk_progress_bar_set_orientation ( (GtkProgressBar *) prg,
+                                       GTK_PROGRESS_LEFT_TO_RIGHT);
+    gtk_box_pack_start ((GtkBox *) gtk_dialog_get_content_area((GtkDialog *) dlg),
+                        prg, FALSE, FALSE, 4 );
+    btn = gtk_dialog_add_button ( GTK_DIALOG (dlg),
+                                  GTK_STOCK_CANCEL,
+                                  GTK_RESPONSE_CANCEL );
+
+    g_signal_connect ( (GObject *) dlg, "delete_event",
+                       (GCallback) onProgressDelete, base);
+    g_signal_connect ( (GObject *) btn, "clicked",
+                       (GCallback) onProgressCancel, base);
+    gtk_window_set_modal ((GtkWindow *) dlg, TRUE);
+    gtk_widget_show_all (dlg);
+
+    return dlg;
+}
+
+// FIXME: Some lib function should be available to do this ...
+gchar * Export::filename_add_extension (const gchar *filename, const gchar *extension)
+{
+  const gchar *dot;
+
+  dot = strrchr (filename, '.');
+  if ( !dot )
+    return g_strconcat (filename, ".", extension, NULL);
+  {
+    if (dot[1] == '\0')
+      return g_strconcat (filename, extension, NULL);
+    else
+    {
+      if (g_ascii_strcasecmp (dot + 1, extension) == 0)
+        return g_strdup (filename);
+      else
+      {
+        return g_strconcat (filename, ".", extension, NULL);
+      }
+    }
+  }
+}
+
+gchar *Export::absolutize_path_from_document_location (SPDocument *doc, const gchar *filename)
+{
+    gchar *path = 0;
+    //Make relative paths go from the document location, if possible:
+    if (!g_path_is_absolute(filename) && doc->getURI()) {
+        gchar *dirname = g_path_get_dirname(doc->getURI());
+        if (dirname) {
+            path = g_build_filename(dirname, filename, NULL);
+            g_free(dirname);
+        }
+    }
+    if (!path) {
+        path = g_strdup(filename);
+    }
+    return path;
+}
+
+/// Called when export button is clicked
+void Export::onExport ()
+{
+    if (!SP_ACTIVE_DESKTOP) return;
+
+    SPNamedView *nv = sp_desktop_namedview(SP_ACTIVE_DESKTOP);
+    SPDocument *doc = sp_desktop_document (SP_ACTIVE_DESKTOP);
+
+    bool hide = hide_export.get_active ();
+    if (batch_export.get_active ()) {
+        // Batch export of selected objects
+
+        gint num = g_slist_length((GSList *) sp_desktop_selection(SP_ACTIVE_DESKTOP)->itemList());
+        gint n = 0;
+
+        if (num < 1)
+            return;
+
+        gchar *progress_text = g_strdup_printf (_("Exporting %d files"), num);
+        GtkWidget *prog_dlg = create_progress_dialog (progress_text);
+        g_free (progress_text);
+
+        for (GSList *i = (GSList *) sp_desktop_selection(SP_ACTIVE_DESKTOP)->itemList();
+             i != NULL;
+             i = i->next) {
+            SPItem *item = reinterpret_cast<SPItem *>(i->data);
+
+            // retrieve export filename hint
+            const gchar *filename = item->getRepr()->attribute("inkscape:export-filename");
+            gchar *path = 0;
+            if (!filename) {
+                path = create_filepath_from_id(item->getId(), NULL);
+            } else {
+                path = absolutize_path_from_document_location(doc, filename);
+            }
+
+            // retrieve export dpi hints
+            const gchar *dpi_hint = item->getRepr()->attribute("inkscape:export-xdpi"); // only xdpi, ydpi is always the same now
+            gdouble dpi = 0.0;
+            if (dpi_hint) {
+                dpi = atof(dpi_hint);
+            }
+            if (dpi == 0.0) {
+                dpi = DPI_BASE;
+            }
+
+            Geom::OptRect area = item->desktopVisualBounds();
+            if (area) {
+                gint width = (gint) (area->width() * dpi / PX_PER_IN + 0.5);
+                gint height = (gint) (area->height() * dpi / PX_PER_IN + 0.5);
+
+                if (width > 1 && height > 1) {
+                    /* Do export */
+                    if (!sp_export_png_file (doc, path,
+                                             *area, width, height, dpi, dpi,
+                                             nv->pagecolor,
+                                             NULL, NULL, TRUE,  // overwrite without asking
+                                             hide ? (GSList *) sp_desktop_selection(SP_ACTIVE_DESKTOP)->itemList() : NULL
+                            )) {
+                        gchar * error;
+                        gchar * safeFile = Inkscape::IO::sanitizeString(path);
+                        error = g_strdup_printf(_("Could not export to filename %s.\n"), safeFile);
+                        sp_ui_error_dialog(error);
+                        g_free(safeFile);
+                        g_free(error);
+                    }
+                }
+            }
+            n++;
+            g_free(path);
+            onProgressCallback((float)n/num, prog_dlg);
+        }
+
+        gtk_widget_destroy (prog_dlg);
+        //g_object_set_data (G_OBJECT (base), "cancel", (gpointer) 0);
+
+    } else {
+
+    gchar const *filename = g_strdup(filename_entry.get_text().c_str());
+
+    float const x0 = getValuePx(x0_adj);
+    float const y0 = getValuePx(y0_adj);
+    float const x1 = getValuePx(x1_adj);
+    float const y1 = getValuePx(y1_adj);
+    float const xdpi = getValue(xdpi_adj);
+    float const ydpi = getValue(ydpi_adj);
+    unsigned long int const width = int(getValue(bmwidth_adj) + 0.5);
+    unsigned long int const height = int(getValue(bmheight_adj) + 0.5);
+
+    if (filename == NULL || *filename == '\0') {
+        sp_ui_error_dialog(_("You have to enter a filename"));
+        return;
+    }
+
+    if (!((x1 > x0) && (y1 > y0) && (width > 0) && (height > 0))) {
+        sp_ui_error_dialog (_("The chosen area to be exported is invalid"));
+        return;
+    }
+
+    // make sure that .png is the extension of the file:
+    gchar * filename_ext = filename_add_extension(filename, "png");
+    //gtk_entry_set_text(GTK_ENTRY(filename_entry), filename_ext);
+    filename_entry.set_text(filename_ext);
+
+    gchar *path = absolutize_path_from_document_location(doc, filename_ext);
+
+    gchar *dirname = g_path_get_dirname(path);
+    if ( dirname == NULL
+         || !Inkscape::IO::file_test(dirname, (GFileTest)(G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR)) )
+    {
+        gchar *safeDir = Inkscape::IO::sanitizeString(dirname);
+        gchar *error = g_strdup_printf(_("Directory %s does not exist or is not a directory.\n"),
+                                       safeDir);
+        sp_ui_error_dialog(error);
+        g_free(safeDir);
+        g_free(error);
+        g_free(dirname);
+        g_free(path);
+        return;
+    }
+    g_free(dirname);
+
+    gchar *fn = g_path_get_basename (path);
+    gchar *progress_text = g_strdup_printf (_("Exporting %s (%lu x %lu)"), fn, width, height);
+    g_free (fn);
+
+    GtkWidget *prog_dlg = create_progress_dialog (progress_text);
+    g_free (progress_text);
+
+    /* Do export */
+    if (!sp_export_png_file (sp_desktop_document (SP_ACTIVE_DESKTOP), path,
+                             Geom::Rect(Geom::Point(x0, y0), Geom::Point(x1, y1)), width, height, xdpi, ydpi,
+                             nv->pagecolor,
+                             onProgressCallback, prog_dlg, FALSE,
+                             hide ? (GSList *) sp_desktop_selection(SP_ACTIVE_DESKTOP)->itemList() : NULL
+            )) {
+        gchar * error;
+        gchar * safeFile = Inkscape::IO::sanitizeString(path);
+        error = g_strdup_printf(_("Could not export to filename %s.\n"), safeFile);
+        sp_ui_error_dialog(error);
+        g_free(safeFile);
+        g_free(error);
+    }
+
+    /* Reset the filename so that it can be changed again by changing
+       selections and all that */
+    g_free(original_name);
+    original_name = g_strdup(filename_ext);
+    filename_modified = false;
+
+    gtk_widget_destroy (prog_dlg);
+    //g_object_set_data (G_OBJECT (base), "cancel", (gpointer) 0);
+
+    /* Setup the values in the document */
+    switch (current_key) {
+        case SELECTION_PAGE:
+        case SELECTION_DRAWING: {
+            SPDocument * doc = SP_ACTIVE_DOCUMENT;
+            Inkscape::XML::Node * repr = doc->getReprRoot();
+            bool modified = false;
+
+            bool saved = DocumentUndo::getUndoSensitive(doc);
+            DocumentUndo::setUndoSensitive(doc, false);
+
+            gchar const *temp_string = repr->attribute("inkscape:export-filename");
+            if (temp_string == NULL || strcmp(temp_string, filename_ext)) {
+                repr->setAttribute("inkscape:export-filename", filename_ext);
+                modified = true;
+            }
+            temp_string = repr->attribute("inkscape:export-xdpi");
+            if (temp_string == NULL || xdpi != atof(temp_string)) {
+                sp_repr_set_svg_double(repr, "inkscape:export-xdpi", xdpi);
+                modified = true;
+            }
+            temp_string = repr->attribute("inkscape:export-ydpi");
+            if (temp_string == NULL || xdpi != atof(temp_string)) {
+                sp_repr_set_svg_double(repr, "inkscape:export-ydpi", ydpi);
+                modified = true;
+            }
+            DocumentUndo::setUndoSensitive(doc, saved);
+
+            if (modified) {
+                doc->setModifiedSinceSave();
+            }
+            break;
+        }
+        case SELECTION_SELECTION: {
+            const GSList * reprlst;
+            SPDocument * doc = SP_ACTIVE_DOCUMENT;
+            bool modified = false;
+
+            bool saved = DocumentUndo::getUndoSensitive(doc);
+            DocumentUndo::setUndoSensitive(doc, false);
+            reprlst = sp_desktop_selection(SP_ACTIVE_DESKTOP)->reprList();
+
+            for(; reprlst != NULL; reprlst = reprlst->next) {
+                Inkscape::XML::Node * repr = (Inkscape::XML::Node *)reprlst->data;
+                const gchar * temp_string;
+                gchar *dir = g_path_get_dirname(filename);
+                gchar *docdir = g_path_get_dirname(SP_ACTIVE_DOCUMENT->getURI());
+
+                if (repr->attribute("id") == NULL ||
+                        !(g_strrstr(filename_ext, repr->attribute("id")) != NULL &&
+                          ( !SP_ACTIVE_DOCUMENT->getURI() ||
+                            strcmp(dir, docdir) == 0))) {
+                    temp_string = repr->attribute("inkscape:export-filename");
+                    if (temp_string == NULL || strcmp(temp_string, filename_ext)) {
+                        repr->setAttribute("inkscape:export-filename", filename_ext);
+                        modified = true;
+                    }
+                }
+                temp_string = repr->attribute("inkscape:export-xdpi");
+                if (temp_string == NULL || xdpi != atof(temp_string)) {
+                    sp_repr_set_svg_double(repr, "inkscape:export-xdpi", xdpi);
+                    modified = true;
+                }
+                temp_string = repr->attribute("inkscape:export-ydpi");
+                if (temp_string == NULL || xdpi != atof(temp_string)) {
+                    sp_repr_set_svg_double(repr, "inkscape:export-ydpi", ydpi);
+                    modified = true;
+                }
+                g_free(dir);
+                g_free(docdir);
+            }
+            DocumentUndo::setUndoSensitive(doc, saved);
+
+            if (modified) {
+                doc->setModifiedSinceSave();
+            }
+            break;
+        }
+        default:
+            break;
+    }
+
+    g_free (filename_ext);
+    g_free (path);
+
+    }
+
+} // end of sp_export_export_clicked()
+
+/// Called when Browse button is clicked
+/// @todo refactor this code to use ui/dialogs/filedialog.cpp
+void Export::onBrowse ()
+{
+    GtkWidget *fs;
+    const gchar *filename;
+
+    fs = gtk_file_chooser_dialog_new (_("Select a filename for exporting"),
+                                      (GtkWindow*)desktop->getToplevel(),
+                                      GTK_FILE_CHOOSER_ACTION_SAVE,
+                                      GTK_STOCK_CANCEL, GTK_RESPONSE_CANCEL,
+                                      GTK_STOCK_SAVE, GTK_RESPONSE_ACCEPT,
+                                      NULL );
+
+#ifdef WITH_GNOME_VFS
+    if (gnome_vfs_initialized()) {
+        gtk_file_chooser_set_local_only(GTK_FILE_CHOOSER(fs), false);
+    }
+#endif
+
+    sp_transientize (fs);
+
+    gtk_window_set_modal(GTK_WINDOW (fs), true);
+
+    filename = filename_entry.get_text().c_str();
+
+    if (*filename == '\0') {
+        filename = create_filepath_from_id(NULL, NULL);
+    }
+
+    gtk_file_chooser_set_filename (GTK_FILE_CHOOSER (fs), filename);
+
+#ifdef WIN32
+    // code in this section is borrowed from ui/dialogs/filedialogimpl-win32.cpp
+    OPENFILENAMEW opf;
+    WCHAR filter_string[20];
+    wcsncpy(filter_string, L"PNG#*.png##", 11);
+    filter_string[3] = L'\0';
+    filter_string[9] = L'\0';
+    filter_string[10] = L'\0';
+    WCHAR* title_string = (WCHAR*)g_utf8_to_utf16(_("Select a filename for exporting"), -1, NULL, NULL, NULL);
+    WCHAR* extension_string = (WCHAR*)g_utf8_to_utf16("*.png", -1, NULL, NULL, NULL);
+    // Copy the selected file name, converting from UTF-8 to UTF-16
+    WCHAR _filename[_MAX_PATH + 1];
+    memset(_filename, 0, sizeof(_filename));
+    gunichar2* utf16_path_string = g_utf8_to_utf16(filename, -1, NULL, NULL, NULL);
+    wcsncpy(_filename, (wchar_t*)utf16_path_string, _MAX_PATH);
+    g_free(utf16_path_string);
+
+    opf.hwndOwner = (HWND)(GDK_WINDOW_HWND(gtk_widget_get_window(GTK_WIDGET(this))));
+    opf.lpstrFilter = filter_string;
+    opf.lpstrCustomFilter = 0;
+    opf.nMaxCustFilter = 0L;
+    opf.nFilterIndex = 1L;
+    opf.lpstrFile = _filename;
+    opf.nMaxFile = _MAX_PATH;
+    opf.lpstrFileTitle = NULL;
+    opf.nMaxFileTitle=0;
+    opf.lpstrInitialDir = 0;
+    opf.lpstrTitle = title_string;
+    opf.nFileOffset = 0;
+    opf.nFileExtension = 2;
+    opf.lpstrDefExt = extension_string;
+    opf.lpfnHook = NULL;
+    opf.lCustData = 0;
+    opf.Flags = OFN_PATHMUSTEXIST;
+    opf.lStructSize = sizeof(OPENFILENAMEW);
+    if (GetSaveFileNameW(&opf) != 0)
+    {
+        // Copy the selected file name, converting from UTF-16 to UTF-8
+        gchar *utf8string = g_utf16_to_utf8((const gunichar2*)opf.lpstrFile, _MAX_PATH, NULL, NULL, NULL);
+        filename_entry.set_text(utf8string);
+        g_free(utf8string);
+
+    }
+    g_free(extension_string);
+    g_free(title_string);
+
+#else
+    if (gtk_dialog_run (GTK_DIALOG (fs)) == GTK_RESPONSE_ACCEPT)
+    {
+        gchar *file;
+
+        file = gtk_file_chooser_get_filename (GTK_FILE_CHOOSER (fs));
+
+        gchar * utf8file = g_filename_to_utf8( file, -1, NULL, NULL, NULL );
+        filename_entry.set_text (utf8file);
+
+        g_free(utf8file);
+        g_free(file);
+    }
+#endif
+
+    gtk_widget_destroy (fs);
+
+    return;
+} // end of sp_export_browse_clicked()
+
+// TODO: Move this to nr-rect-fns.h.
+bool Export::bbox_equal(Geom::Rect const &one, Geom::Rect const &two)
+{
+    double const epsilon = pow(10.0, -EXPORT_COORD_PRECISION);
+    return (
+        (fabs(one.min()[Geom::X] - two.min()[Geom::X]) < epsilon) &&
+        (fabs(one.min()[Geom::Y] - two.min()[Geom::Y]) < epsilon) &&
+        (fabs(one.max()[Geom::X] - two.max()[Geom::X]) < epsilon) &&
+        (fabs(one.max()[Geom::Y] - two.max()[Geom::Y]) < epsilon)
+        );
+}
+
+/**
+ *This function is used to detect the current selection setting
+ * based on the values in the x0, y0, x1 and y0 fields.
+ *
+ * One of the most confusing parts of this function is why the array
+ * is built at the beginning.  What needs to happen here is that we
+ * should always check the current selection to see if it is the valid
+ * one.  While this is a performance improvement it is also a usability
+ * one during the cases where things like selections and drawings match
+ * size.  This way buttons change less 'randomly' (atleast in the eyes
+ * of the user).  To do this an array is built where the current selection
+ * type is placed first, and then the others in an order from smallest
+ * to largest (this can be configured by reshuffling \c test_order).
+ *
+ * All of the values in this function are rounded to two decimal places
+ * because that is what is shown to the user.  While everything is kept
+ * more accurate than that, the user can't control more acurrate than
+ * that, so for this to work for them - it needs to check on that level
+ * of accuracy.
+ *
+ * @todo finish writing this up.
+ */
+void Export::detectSize() {
+    static const selection_type test_order[SELECTION_NUMBER_OF] = {SELECTION_SELECTION, SELECTION_DRAWING, SELECTION_PAGE, SELECTION_CUSTOM};
+    selection_type this_test[SELECTION_NUMBER_OF + 1];
+    selection_type key = SELECTION_NUMBER_OF;
+    
+    Geom::Point x(getValuePx(x0_adj),
+                  getValuePx(y0_adj));
+    Geom::Point y(getValuePx(x1_adj),
+                  getValuePx(y1_adj));
+    Geom::Rect current_bbox(x, y);
+
+    this_test[0] = current_key;
+    for (int i = 0; i < SELECTION_NUMBER_OF; i++) {
+        this_test[i + 1] = test_order[i];
+    }
+
+    for (int i = 0;
+            i < SELECTION_NUMBER_OF + 1 &&
+                key == SELECTION_NUMBER_OF &&
+                SP_ACTIVE_DESKTOP != NULL;
+            i++) {
+        switch (this_test[i]) {
+            case SELECTION_SELECTION:
+                if ((sp_desktop_selection(SP_ACTIVE_DESKTOP))->isEmpty() == false) {
+                    Geom::OptRect bbox = (sp_desktop_selection (SP_ACTIVE_DESKTOP))->bounds(SPItem::VISUAL_BBOX);
+
+                    if ( bbox && bbox_equal(*bbox,current_bbox)) {
+                        key = SELECTION_SELECTION;
+                    }
+                }
+                break;
+            case SELECTION_DRAWING: {
+                SPDocument *doc = sp_desktop_document (SP_ACTIVE_DESKTOP);
+
+                Geom::OptRect bbox = doc->getRoot()->desktopVisualBounds();
+
+                if ( bbox && bbox_equal(*bbox,current_bbox) ) {
+                    key = SELECTION_DRAWING;
+                }
+                break;
+            }
+
+            case SELECTION_PAGE: {
+                SPDocument *doc;
+
+                doc = sp_desktop_document (SP_ACTIVE_DESKTOP);
+
+                Geom::Point x(0.0, 0.0);
+                Geom::Point y(doc->getWidth(),
+                              doc->getHeight());
+                Geom::Rect bbox(x, y);
+
+                if (bbox_equal(bbox,current_bbox)) {
+                    key = SELECTION_PAGE;
+                }
+
+                break;
+           }
+        default:
+           break;
+        }
+    }
+    // std::cout << std::endl;
+
+    if (key == SELECTION_NUMBER_OF) {
+        key = SELECTION_CUSTOM;
+    }
+
+    current_key = key;
+    selectiontype_buttons[current_key]->set_active(true);
+
+    return;
+} /* sp_export_detect_size */
+
+/// Called when area x0 value is changed
+void Export::areaXChange (Gtk::Adjustment *adj)
+{
+    float x0, x1, xdpi, width;
+
+    if (update) {
+        return;
+    }
+
+    if (sp_unit_selector_update_test ((SPUnitSelector *)unit_selector->gobj())) {
+        return;
+    }
+
+    update = true;
+
+    x0 = getValuePx(x0_adj);
+    x1 = getValuePx(x1_adj);
+    xdpi = getValue(xdpi_adj);
+
+    width = floor ((x1 - x0) * xdpi / DPI_BASE + 0.5);
+
+    if (width < SP_EXPORT_MIN_SIZE) {
+        width = SP_EXPORT_MIN_SIZE;
+
+        if (adj == x1_adj) {
+            x1 = x0 + width * DPI_BASE / xdpi;
+            setValuePx(x1_adj, x1);
+        } else {
+            x0 = x1 - width * DPI_BASE / xdpi;
+            setValuePx(x0_adj, x0);
+        }
+    }
+
+    setValuePx(width_adj, x1 - x0);
+    setValue(bmwidth_adj, width);
+
+    detectSize();
+
+    update = false;
+
+    return;
+} // end of sp_export_area_x_value_changed()
+
+/// Called when area y0 value is changed.
+void Export::areaYChange (Gtk::Adjustment *adj)
+{
+    float y0, y1, ydpi, height;
+
+    if (update) {
+        return;
+    }
+
+    if (sp_unit_selector_update_test ((SPUnitSelector *)unit_selector->gobj()))  {
+        return;
+    }
+
+    update = true;
+
+    y0 = getValuePx(y0_adj);
+    y1 = getValuePx(y1_adj);
+    ydpi = getValue(ydpi_adj);
+
+    height = floor ((y1 - y0) * ydpi / DPI_BASE + 0.5);
+
+    if (height < SP_EXPORT_MIN_SIZE) {
+        //const gchar *key;
+        height = SP_EXPORT_MIN_SIZE;
+        //key = (const gchar *)g_object_get_data(G_OBJECT (adj), "key");
+        if (adj == y1_adj) {
+        //if (!strcmp (key, "y0")) {
+            y1 = y0 + height * DPI_BASE / ydpi;
+            setValuePx(y1_adj, y1);
+        } else {
+            y0 = y1 - height * DPI_BASE / ydpi;
+            setValuePx(y0_adj, y0);
+        }
+    }
+
+    setValuePx(height_adj, y1 - y0);
+    setValue(bmheight_adj, height);
+
+    detectSize();
+
+    update = false;
+
+    return;
+} // end of sp_export_area_y_value_changed()
+
+/// Called when x1-x0 or area width is changed
+void Export::onAreaWidthChange()
+{
+    if (update) {
+        return;
+    }
+
+    if (sp_unit_selector_update_test(reinterpret_cast<SPUnitSelector *>(unit_selector->gobj()))) {
+        return;
+    }
+
+    update = true;
+
+    float x0 = getValuePx(x0_adj);
+    float xdpi = getValue(xdpi_adj);
+    float width = getValuePx(width_adj);
+    float bmwidth = floor(width * xdpi / DPI_BASE + 0.5);
+
+    if (bmwidth < SP_EXPORT_MIN_SIZE) {
+
+        bmwidth = SP_EXPORT_MIN_SIZE;
+        width = bmwidth * DPI_BASE / xdpi;
+        setValuePx(width_adj, width);
+    }
+
+    setValuePx(x1_adj, x0 + width);
+    setValue(bmwidth_adj, bmwidth);
+
+    update = false;
+
+    return;
+} // end of sp_export_area_width_value_changed()
+
+/// Called when y1-y0 or area height is changed.
+void Export::onAreaHeightChange()
+{
+    if (update) {
+        return;
+    }
+
+    if (sp_unit_selector_update_test(reinterpret_cast<SPUnitSelector *>(unit_selector->gobj()))) {
+        return;
+    }
+
+    update = true;
+
+    float y0 = getValuePx(y0_adj);
+    //float y1 = sp_export_value_get_px(y1_adj);
+    float ydpi = getValue(ydpi_adj);
+    float height = getValuePx(height_adj);
+    float bmheight = floor (height * ydpi / DPI_BASE + 0.5);
+
+    if (bmheight < SP_EXPORT_MIN_SIZE) {
+        bmheight = SP_EXPORT_MIN_SIZE;
+        height = bmheight * DPI_BASE / ydpi;
+        setValuePx(height_adj, height);
+    }
+
+    setValuePx(y1_adj, y0 + height);
+    setValue(bmheight_adj, bmheight);
+
+    update = false;
+
+    return;
+} // end of sp_export_area_height_value_changed()
+
+/**
+ * A function to set the ydpi.
+ * @param base The export dialog.
+ *
+ * This function grabs all of the y values and then figures out the
+ * new bitmap size based on the changing dpi value.  The dpi value is
+ * gotten from the xdpi setting as these can not currently be independent.
+ */
+void Export::setImageY()
+{
+    float y0, y1, xdpi;
+
+    y0 = getValuePx(y0_adj);
+    y1 = getValuePx(y1_adj);
+    xdpi = getValue(xdpi_adj);
+
+    setValue(ydpi_adj, xdpi);
+    setValue(bmheight_adj, (y1 - y0) * xdpi / DPI_BASE);
+
+    return;
+} // end of setImageY()
+
+/**
+ * A function to set the xdpi.
+ *
+ * This function grabs all of the x values and then figures out the
+ * new bitmap size based on the changing dpi value.  The dpi value is
+ * gotten from the xdpi setting as these can not currently be independent.
+ *
+ */
+void Export::setImageX()
+{
+    float x0, x1, xdpi;
+
+    x0 = getValuePx(x0_adj);
+    x1 = getValuePx(x1_adj);
+    xdpi = getValue(xdpi_adj);
+
+    setValue(ydpi_adj, xdpi);
+    setValue(bmwidth_adj, (x1 - x0) * xdpi / DPI_BASE);
+
+    return;
+} // end of setImageX()
+
+/// Called when pixel width is changed
+void Export::onBitmapWidthChange ()
+{
+    float x0, x1, bmwidth, xdpi;
+
+    if (update) {
+        return;
+    }
+
+    if (sp_unit_selector_update_test ((SPUnitSelector *)unit_selector->gobj())) {
+       return;
+    }
+
+    update = true;
+
+    x0 = getValuePx(x0_adj);
+    x1 = getValuePx(x1_adj);
+    bmwidth = getValue(bmwidth_adj);
+
+    if (bmwidth < SP_EXPORT_MIN_SIZE) {
+        bmwidth = SP_EXPORT_MIN_SIZE;
+        setValue(bmwidth_adj, bmwidth);
+    }
+
+    xdpi = bmwidth * DPI_BASE / (x1 - x0);
+    setValue(xdpi_adj, xdpi);
+
+    setImageY ();
+
+    update = false;
+
+    return;
+} // end of sp_export_bitmap_width_value_changed()
+
+/// Called when pixel height is changed
+void Export::onBitmapHeightChange ()
+{
+    float y0, y1, bmheight, xdpi;
+
+    if (update) {
+        return;
+    }
+
+    if (sp_unit_selector_update_test ((SPUnitSelector *)unit_selector->gobj())) {
+       return;
+    }
+
+    update = true;
+
+    y0 = getValuePx(y0_adj);
+    y1 = getValuePx(y1_adj);
+    bmheight = getValue(bmheight_adj);
+
+    if (bmheight < SP_EXPORT_MIN_SIZE) {
+        bmheight = SP_EXPORT_MIN_SIZE;
+        setValue(bmheight_adj, bmheight);
+    }
+
+    xdpi = bmheight * DPI_BASE / (y1 - y0);
+    setValue(xdpi_adj, xdpi);
+
+    setImageX ();
+
+    update = false;
+
+    return;
+} // end of sp_export_bitmap_width_value_changed()
+
+/**
+ * A function to adjust the bitmap width when the xdpi value changes.
+ *
+ * The first thing this function checks is to see if we are doing an
+ * update.  If we are, this function just returns because there is another
+ * instance of it that will handle everything for us.  If there is a
+ * units change, we also assume that everyone is being updated appropriately
+ * and there is nothing for us to do.
+ *
+ * If we're the highest level function, we set the update flag, and
+ * continue on our way.
+ *
+ * All of the values are grabbed using the \c sp_export_value_get functions
+ * (call to the _pt ones for x0 and x1 but just standard for xdpi).  The
+ * xdpi value is saved in the preferences for the next time the dialog
+ * is opened.  (does the selection dpi need to be set here?)
+ *
+ * A check is done to to ensure that we aren't outputing an invalid width,
+ * this is set by SP_EXPORT_MIN_SIZE.  If that is the case the dpi is
+ * changed to make it valid.
+ *
+ * After all of this the bitmap width is changed.
+ *
+ * We also change the ydpi.  This is a temporary hack as these can not
+ * currently be independent.  This is likely to change in the future.
+ *
+ */
+void Export::onExportXdpiChange()
+{
+    float x0, x1, xdpi, bmwidth;
+
+    if (update) {
+        return;
+    }
+
+    if (sp_unit_selector_update_test ((SPUnitSelector *)unit_selector->gobj())) {
+       return;
+    }
+
+    update = true;
+
+    x0 = getValuePx(x0_adj);
+    x1 = getValuePx(x1_adj);
+    xdpi = getValue(xdpi_adj);
+
+    // remember xdpi setting
+    prefs->setDouble("/dialogs/export/defaultxdpi/value", xdpi);
+
+    bmwidth = (x1 - x0) * xdpi / DPI_BASE;
+
+    if (bmwidth < SP_EXPORT_MIN_SIZE) {
+        bmwidth = SP_EXPORT_MIN_SIZE;
+        if (x1 != x0)
+            xdpi = bmwidth * DPI_BASE / (x1 - x0);
+        else
+            xdpi = DPI_BASE;
+        setValue(xdpi_adj, xdpi);
+    }
+
+    setValue(bmwidth_adj, bmwidth);
+
+    setImageY ();
+
+    update = false;
+
+    return;
+} // end of sp_export_xdpi_value_changed()
+
+
+/**
+ * A function to change the area that is used for the exported.
+ * bitmap.
+ *
+ * This function just calls \c sp_export_value_set_px for each of the
+ * parameters that is passed in.  This allows for setting them all in
+ * one convient area.
+ *
+ * Update is set to suspend all of the other test running while all the
+ * values are being set up.  This allows for a performance increase, but
+ * it also means that the wrong type won't be detected with only some of
+ * the values set.  After all the values are set everyone is told that
+ * there has been an update.
+ *
+ * @param  x0    Horizontal upper left hand corner of the picture in points.
+ * @param  y0    Vertical upper left hand corner of the picture in points.
+ * @param  x1    Horizontal lower right hand corner of the picture in points.
+ * @param  y1    Vertical lower right hand corner of the picture in points.
+ */
+void Export::setArea( double x0, double y0, double x1, double y1 )
+{
+    update = true;
+    setValuePx(x1_adj, x1);
+    setValuePx(y1_adj, y1);
+    setValuePx(x0_adj, x0);
+    setValuePx(y0_adj, y0);
+    update = false;
+
+    areaXChange (x1_adj);
+    areaYChange (y1_adj);
+
+    return;
+}
+
+/**
+ * Sets the value of an adjustment.
+ *
+ * @param  adj   The adjustment widget
+ * @param  val   What value to set it to.
+ */
+void Export::setValue(  Gtk::Adjustment *adj, double val )
+{
+    if (adj) {
+        adj->set_value(val);
+    }
+}
+
+/**
+ * A function to set a value using the units points.
+ *
+ * This function first gets the adjustment for the key that is passed
+ * in.  It then figures out what units are currently being used in the
+ * dialog.  After doing all of that, it then converts the incoming
+ *value and sets the adjustment.
+ *
+ * @param  adj   The adjustment widget
+ * @param  val   What the value should be in points.
+ */
+void Export::setValuePx( Gtk::Adjustment *adj, double val)
+{
+    const SPUnit *unit = sp_unit_selector_get_unit ((SPUnitSelector *)unit_selector->gobj() );
+
+    setValue(adj, sp_pixels_get_units (val, *unit));
+
+    return;
+}
+
+/**
+ * Get the value of an adjustment in the export dialog.
+ *
+ * This function gets the adjustment from the data field in the export
+ * dialog.  It then grabs the value from the adjustment.
+ *
+ * @param  adj   The adjustment widget
+ *
+ * @return The value in the specified adjustment.
+ */
+float Export::getValue(  Gtk::Adjustment *adj )
+{
+    if (!adj) {
+        g_message("sp_export_value_get : adj is NULL");
+        return 0.0;
+    }
+    return adj->get_value();
+}
+
+/**
+ * Grabs a value in the export dialog and converts the unit
+ * to points.
+ *
+ * This function, at its most basic, is a call to \c sp_export_value_get
+ * to get the value of the adjustment.  It then finds the units that
+ * are being used by looking at the "units" attribute of the export
+ * dialog.  Using that it converts the returned value into points.
+ *
+ * @param  adj   The adjustment widget
+ *
+ * @return The value in the adjustment in points.
+ */
+float Export::getValuePx(  Gtk::Adjustment *adj )
+{
+    float value = getValue( adj);
+    const SPUnit *unit = sp_unit_selector_get_unit ((SPUnitSelector *)unit_selector->gobj());
+
+    return sp_units_get_pixels (value, *unit);
+} // end of sp_export_value_get_px()
+
+/**
+ * This function is called when the filename is changed by
+ * anyone.  It resets the virgin bit.
+ *
+ * This function gets called when the text area is modified.  It is
+ * looking for the case where the text area is modified from its
+ * original value.  In that case it sets the "filename-modified" bit
+ * to TRUE.  If the text dialog returns back to the original text, the
+ * bit gets reset.  This should stop simple mistakes.
+ */
+void Export::onFilenameModified()
+{
+    if (strcmp(original_name, filename_entry.get_text().c_str())==0) {
+        filename_modified = false;
+//        g_message("Modified: FALSE\n");
+    } else {
+        filename_modified = true;
+//        g_message("Modified: TRUE\n");
+    }
+
+    return;
+} // end sp_export_filename_modified
+
+}
+}
+}
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :