Enable SimpleFilterModifier to handle blend and blur filter primitives at the same time.

Add opacity to SimpleFilterModifier.
Use SimpleFilterModifier in Layers, Objects, and Fill and Stroke dialogs.

8 files changed, 129 insertions, 173 deletions

diff --git a/src/ui/dialog/fill-and-stroke.cpp b/src/ui/dialog/fill-and-stroke.cpp
index b271c951b..513cee752 100644
--- a/src/ui/dialog/fill-and-stroke.cpp
+++ b/src/ui/dialog/fill-and-stroke.cpp
@@ -42,7 +42,9 @@ FillAndStroke::FillAndStroke()
       _page_fill(Gtk::manage(new UI::Widget::NotebookPage(1, 1, true, true))),
       _page_stroke_paint(Gtk::manage(new UI::Widget::NotebookPage(1, 1, true, true))),
       _page_stroke_style(Gtk::manage(new UI::Widget::NotebookPage(1, 1, true, true))),
-      _composite_settings(SP_VERB_DIALOG_FILL_STROKE, "fillstroke", UI::Widget::SimpleFilterModifier::BLUR),
+      _composite_settings(SP_VERB_DIALOG_FILL_STROKE, "fillstroke",
+                          UI::Widget::SimpleFilterModifier::BLUR |
+                          UI::Widget::SimpleFilterModifier::OPACITY ),
       deskTrack(),
       targetDesktop(0),
       fillWdgt(0),
diff --git a/src/ui/dialog/layers.cpp b/src/ui/dialog/layers.cpp
index 6223bd627..5bbf4c952 100644
--- a/src/ui/dialog/layers.cpp
+++ b/src/ui/dialog/layers.cpp
@@ -799,7 +799,10 @@ LayersPanel::LayersPanel() :
     _model(0),
     _pending(0),
     _toggleEvent(0),
-    _compositeSettings(SP_VERB_DIALOG_LAYERS, "layers", UI::Widget::SimpleFilterModifier::BLEND),
+    _compositeSettings(SP_VERB_DIALOG_LAYERS, "layers",
+                       UI::Widget::SimpleFilterModifier::BLEND |
+                       UI::Widget::SimpleFilterModifier::OPACITY |
+                       UI::Widget::SimpleFilterModifier::BLUR),
     desktopChangeConn()
 {
     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
diff --git a/src/ui/dialog/objects.cpp b/src/ui/dialog/objects.cpp
index b50d68239..07fdb2bd7 100644
--- a/src/ui/dialog/objects.cpp
+++ b/src/ui/dialog/objects.cpp
@@ -4,8 +4,10 @@
  * Authors:
  *   Theodore Janeczko
  *   Tweaked by Liam P White for use in Inkscape
+ *   Tavmjong Bah
  *
  * Copyright (C) Theodore Janeczko 2012 <flutterguy317@gmail.com>
+ *               Tavmjong Bah 2017
  *
  * Released under GNU GPL, read the file 'COPYING' for more information
  */
@@ -509,27 +511,30 @@ void ObjectsPanel::_objectsSelected( Selection *sel ) {
  */
 void ObjectsPanel::_setCompositingValues(SPItem *item)
 {
-    //Block the connections to avoid interference
+    // Block the connections to avoid interference
     _opacityConnection.block();
     _blendConnection.block();
     _blurConnection.block();
 
-    //Set the opacity
-    _opacity_adjustment->set_value((item->style->opacity.set ? SP_SCALE24_TO_FLOAT(item->style->opacity.value) : 1) * _opacity_adjustment->get_upper());
+    // Set the opacity
+    double opacity = (item->style->opacity.set ? SP_SCALE24_TO_FLOAT(item->style->opacity.value) : 1);
+    opacity *= 100; // Display in percent.
+    _filter_modifier.set_opacity_value(opacity);
+
     SPFeBlend *spblend = NULL;
     SPGaussianBlur *spblur = NULL;
-    if (item->style->getFilter())
-    {
+    if (item->style->getFilter()) {
+
         for (auto& primitive_obj: item->style->getFilter()->children) {
             if (!SP_IS_FILTER_PRIMITIVE(&primitive_obj)) {
                 break;
             }
-            if(SP_IS_FEBLEND(&primitive_obj) && !spblend) {
+            if (SP_IS_FEBLEND(&primitive_obj) && !spblend) {
                 //Get the blend mode
                 spblend = SP_FEBLEND(&primitive_obj);
             }
 
-            if(SP_IS_GAUSSIANBLUR(&primitive_obj) && !spblur) {
+            if (SP_IS_GAUSSIANBLUR(&primitive_obj) && !spblur) {
                 //Get the blur value
                 spblur = SP_GAUSSIANBLUR(&primitive_obj);
             }
@@ -537,15 +542,15 @@ void ObjectsPanel::_setCompositingValues(SPItem *item)
     }
 
     //Set the blend mode
-    _fe_cb.set_blend_mode(spblend ? spblend->blend_mode : Inkscape::Filters::BLEND_NORMAL);
-    
+    _filter_modifier.set_blend_mode(spblend ? spblend->blend_mode : Inkscape::Filters::BLEND_NORMAL);
+
     //Set the blur value
     Geom::OptRect bbox = item->bounds(SPItem::GEOMETRIC_BBOX);
     if (bbox && spblur) {
         double perimeter = bbox->dimensions()[Geom::X] + bbox->dimensions()[Geom::Y];   // fixme: this is only half the perimeter, is that correct?
-        _fe_blur.set_blur_value(spblur->stdDeviation.getNumber() * 400 / perimeter);
+        _filter_modifier.set_blur_value(spblur->stdDeviation.getNumber() * 400 / perimeter);
     } else {
-        _fe_blur.set_blur_value(0);
+        _filter_modifier.set_blur_value(0);
     }
     
     //Unblock connections
@@ -1494,7 +1499,7 @@ void ObjectsPanel::_opacityChangedIter(const Gtk::TreeIter& iter)
     if (item)
     {
         item->style->opacity.set = TRUE;
-        item->style->opacity.value = SP_SCALE24_FROM_FLOAT(_opacity_adjustment->get_value() / _opacity_adjustment->get_upper());
+        item->style->opacity.value = SP_SCALE24_FROM_FLOAT(_filter_modifier.get_opacity_value() / 100);
         item->updateRepr(SP_OBJECT_WRITE_NO_CHILDREN | SP_OBJECT_WRITE_EXT);
     }
 }
@@ -1505,7 +1510,7 @@ void ObjectsPanel::_opacityChangedIter(const Gtk::TreeIter& iter)
 void ObjectsPanel::_blendValueChanged()
 {
     _blockCompositeUpdate = true;
-    const Glib::ustring blendmode = _fe_cb.get_blend_mode();
+    const Glib::ustring blendmode = _filter_modifier.get_blend_mode();
 
     _tree.get_selection()->selected_foreach_iter(sigc::bind<Glib::ustring>(sigc::mem_fun(*this, &ObjectsPanel::_blendChangedIter), blendmode));
     DocumentUndo::done(_document, SP_VERB_DIALOG_OBJECTS, _("Set object blend mode"));
@@ -1534,11 +1539,12 @@ void ObjectsPanel::_blendChangedIter(const Gtk::TreeIter& iter, Glib::ustring bl
                     if (!SP_IS_FILTER_PRIMITIVE(&primitive)) {
                         break;
                     }
+                    // We should read in the current radius and use that!
                     if (SP_IS_GAUSSIANBLUR(&primitive)) {
                         Geom::OptRect bbox = item->bounds(SPItem::GEOMETRIC_BBOX);
                         if (bbox) {
                             double perimeter = bbox->dimensions()[Geom::X] + bbox->dimensions()[Geom::Y];   // fixme: this is only half the perimeter, is that correct?
-                            radius =  _fe_blur.get_blur_value() * perimeter / 400;
+                            radius =  _filter_modifier.get_blur_value() * perimeter / 400;
                         }
                     }
                 }
@@ -1576,7 +1582,7 @@ void ObjectsPanel::_blendChangedIter(const Gtk::TreeIter& iter, Glib::ustring bl
 void ObjectsPanel::_blurValueChanged()
 {
     _blockCompositeUpdate = true;
-    _tree.get_selection()->selected_foreach_iter(sigc::bind<double>(sigc::mem_fun(*this, &ObjectsPanel::_blurChangedIter), _fe_blur.get_blur_value()));
+    _tree.get_selection()->selected_foreach_iter(sigc::bind<double>(sigc::mem_fun(*this, &ObjectsPanel::_blurChangedIter), _filter_modifier.get_blur_value()));
     DocumentUndo::maybeDone(_document, "blur", SP_VERB_DIALOG_OBJECTS, _("Set object blur"));    
     _blockCompositeUpdate = false;
 }
@@ -1649,17 +1655,9 @@ ObjectsPanel::ObjectsPanel() :
     _clipmaskHeader(C_("Clip and mask", "CM")),
     _highlightHeader(C_("Highlight", "HL")),
     _nameHeader(_("Label")),
-    _composite_vbox(Gtk::ORIENTATION_VERTICAL),
-    _opacity_vbox(Gtk::ORIENTATION_VERTICAL),
-    _opacity_label(_("Opacity:")),
-    _opacity_label_unit(_("%")),
-    _opacity_adjustment(Gtk::Adjustment::create(100.0, 0.0, 100.0, 1.0, 1.0, 0.0)),
-    _opacity_hscale(_opacity_adjustment),
-    _opacity_spin_button(_opacity_adjustment, 0.01, 1),
-    _fe_cb(UI::Widget::SimpleFilterModifier::BLEND),
-    _fe_vbox(Gtk::ORIENTATION_VERTICAL),
-    _fe_blur(UI::Widget::SimpleFilterModifier::BLUR),
-    _blur_vbox(Gtk::ORIENTATION_VERTICAL),
+    _filter_modifier( UI::Widget::SimpleFilterModifier::BLEND   |
+                      UI::Widget::SimpleFilterModifier::BLUR    |
+                      UI::Widget::SimpleFilterModifier::OPACITY ),
     _colorSelectorDialog("dialogs.colorpickerwindow")
 {
     //Create the tree model and store
@@ -1794,58 +1792,12 @@ ObjectsPanel::ObjectsPanel() :
     _page.pack_start( _scroller, Gtk::PACK_EXPAND_WIDGET );
 
     //Set up the compositing items
-    //Blend mode filter effect
-    _composite_vbox.pack_start(_fe_vbox, false, false, 2);
-
-    _fe_cb.set_halign(Gtk::ALIGN_FILL);
-    _fe_cb.set_valign(Gtk::ALIGN_END);
-
-#if WITH_GTKMM_3_12
-    _fe_cb.set_margin_start(4);
-#else
-    _fe_cb.set_margin_left(4);
-#endif
-
-    _fe_vbox.pack_start(_fe_cb, false, false, 0);
-    _blendConnection = _fe_cb.signal_blend_blur_changed().connect(sigc::mem_fun(*this, &ObjectsPanel::_blendValueChanged));
-
-    //Blur filter effect
-    _composite_vbox.pack_start(_blur_vbox, false, false, 2);
-
-    _fe_blur.set_hexpand();
-    _fe_blur.set_halign(Gtk::ALIGN_FILL);
-    _fe_blur.set_valign(Gtk::ALIGN_END);
-    
-#if WITH_GTKMM_3_12
-    _fe_blur.set_margin_start(4);
-#else
-    _fe_blur.set_margin_left(4);
-#endif
-
-    _blur_vbox.pack_start(_fe_blur, false, false, 0);
-    _blurConnection = _fe_blur.signal_blend_blur_changed().connect(sigc::mem_fun(*this, &ObjectsPanel::_blurValueChanged));
-    
-    //Opacity
-    _composite_vbox.pack_start(_opacity_vbox, false, false, 2);
-    _opacity_label.set_halign(Gtk::ALIGN_END);
-    _opacity_label.set_valign(Gtk::ALIGN_CENTER);
-    _opacity_hbox.pack_start(_opacity_label, false, false, 3);
-    _opacity_vbox.pack_start(_opacity_hbox, false, false, 0);
-    _opacity_hbox.pack_start(_opacity_hscale, true, true, 0);
-    _opacity_hbox.pack_start(_opacity_spin_button, false, false, 0);
-    _opacity_hbox.pack_start(_opacity_label_unit, false, false, 3);
-    _opacity_hscale.set_draw_value(false);
-    _opacityConnection = _opacity_adjustment->signal_value_changed().connect(sigc::mem_fun(*this, &ObjectsPanel::_opacityValueChanged));
-    _opacity_label.set_mnemonic_widget(_opacity_hscale);
-    
-    //Keep the labels aligned
-    GtkSizeGroup *labels = gtk_size_group_new(GTK_SIZE_GROUP_HORIZONTAL);
-    gtk_size_group_add_widget(labels, GTK_WIDGET(_opacity_label.gobj()));
-    gtk_size_group_add_widget(labels, GTK_WIDGET(_fe_cb.get_blur_label()->gobj()));
-    gtk_size_group_add_widget(labels, GTK_WIDGET(_fe_blur.get_blur_label()->gobj()));
+    _blendConnection   = _filter_modifier.signal_blend_changed().connect(sigc::mem_fun(*this, &ObjectsPanel::_blendValueChanged));
+    _blurConnection    = _filter_modifier.signal_blur_changed().connect(sigc::mem_fun(*this, &ObjectsPanel::_blurValueChanged));
+    _opacityConnection = _filter_modifier.signal_opacity_changed().connect(   sigc::mem_fun(*this, &ObjectsPanel::_opacityValueChanged));
 
     //Pack the compositing functions and the button row
-    _page.pack_end(_composite_vbox, Gtk::PACK_SHRINK);
+    _page.pack_end(_filter_modifier, Gtk::PACK_SHRINK);
     _page.pack_end(_buttonsRow, Gtk::PACK_SHRINK);
 
     //Pack into the panel contents
@@ -1914,7 +1866,7 @@ ObjectsPanel::ObjectsPanel() :
     _buttonsRow.pack_start(_buttonsSecondary, Gtk::PACK_EXPAND_WIDGET);
     _buttonsRow.pack_end(_buttonsPrimary, Gtk::PACK_EXPAND_WIDGET);
 
-    _watching.push_back(&_composite_vbox);
+    _watching.push_back(&_filter_modifier);
     
     //Set up the pop-up menu
     // -------------------------------------------------------
diff --git a/src/ui/dialog/objects.h b/src/ui/dialog/objects.h
index 73a0f0643..439e3af2a 100644
--- a/src/ui/dialog/objects.h
+++ b/src/ui/dialog/objects.h
@@ -3,8 +3,10 @@
  *
  * Authors:
  *   Theodore Janeczko
+ *   Tavmjong Bah
  *
  * Copyright (C) Theodore Janeczko 2012 <flutterguy317@gmail.com>
+ *               Tavmjong Bah 2017
  *
  * Released under GNU GPL, read the file 'COPYING' for more information
  */
@@ -151,20 +153,8 @@ private:
     Gtk::Label _highlightHeader;
     Gtk::Label _nameHeader;
 
-    /* Composite Settings */
-    Gtk::Box        _composite_vbox;
-    Gtk::Box        _opacity_vbox;
-    Gtk::Box        _opacity_hbox;
-    Gtk::Label      _opacity_label;
-    Gtk::Label      _opacity_label_unit;
-    Glib::RefPtr<Gtk::Adjustment> _opacity_adjustment;
-    Gtk::Scale      _opacity_hscale;
-    Inkscape::UI::Widget::SpinButton _opacity_spin_button;
-    
-    Inkscape::UI::Widget::SimpleFilterModifier _fe_cb;
-    Gtk::Box        _fe_vbox;
-    Inkscape::UI::Widget::SimpleFilterModifier _fe_blur;
-    Gtk::Box        _blur_vbox;
+    /* Composite Settings (blend, blur, opacity). */
+    Inkscape::UI::Widget::SimpleFilterModifier _filter_modifier;
 
     Gtk::Dialog _colorSelectorDialog;
     std::unique_ptr<Inkscape::UI::SelectedColor> _selectedColor;
diff --git a/src/ui/widget/filter-effect-chooser.cpp b/src/ui/widget/filter-effect-chooser.cpp
index 30506851c..c19aa037a 100644
--- a/src/ui/widget/filter-effect-chooser.cpp
+++ b/src/ui/widget/filter-effect-chooser.cpp
@@ -3,8 +3,9 @@
  *
  * Author:
  *   Nicholas Bishop <nicholasbishop@gmail.com>
+ *   Tavmjong Bah
  *
- * Copyright (C) 2007 Authors
+ * Copyright (C) 2007, 2017 Authors
  *
  * Released under GNU GPL, read the file 'COPYING' for more information
  */
@@ -18,11 +19,11 @@ namespace UI {
 namespace Widget {
 
 SimpleFilterModifier::SimpleFilterModifier(int flags)
-    : _lb_blend(_("Blend mode:")),
-      _lb_blur(_("_Blur:")),
-      _lb_blur_unit(_("%")),
-      _blend(BlendModeConverter, SP_ATTR_INVALID, false),
-      _blur(_("Blur (%)"), 0, 0, 100, 1, 1, 1)
+    : _flags( flags )
+    , _lb_blend(_("Blend mode:"))
+    , _blend(BlendModeConverter, SP_ATTR_INVALID, false)
+    , _blur(   _("Blur (%)"   ), 0, 0, 100, 1, 1, 1)
+    , _opacity(_("Opacity (%)"), 0, 0, 100, 1, 1, 1)
 {
     set_name("SimpleFilterModifier");
 
@@ -30,25 +31,40 @@ SimpleFilterModifier::SimpleFilterModifier(int flags)
 
     if (flags & BLEND) {
         add(_hb_blend);
+        _lb_blend.set_use_underline();
+        _lb_blend.set_mnemonic_widget(_blend);
         _hb_blend.pack_start(_lb_blend, false, false, 0);
         _hb_blend.pack_start(_blend);
     }
+
     if (flags & BLUR) {
         add(_blur);
     }
 
+    if (flags & OPACITY) {
+        add(_opacity);
+    }
+
     show_all_children();
 
-    _hb_blend.set_spacing(12);
-    _lb_blend.set_use_underline();
-    _lb_blend.set_mnemonic_widget(_blend);
-    _blend.signal_changed().connect(signal_blend_blur_changed());
-    _blur.signal_value_changed().connect(signal_blend_blur_changed());
+    _blend.signal_changed().connect(signal_blend_changed());
+    _blur.signal_value_changed().connect(signal_blur_changed());
+    _opacity.signal_value_changed().connect(signal_opacity_changed());
+}
+
+sigc::signal<void>& SimpleFilterModifier::signal_blend_changed()
+{
+    return _signal_blend_changed;
+}
+
+sigc::signal<void>& SimpleFilterModifier::signal_blur_changed()
+{
+    return _signal_blur_changed;
 }
 
-sigc::signal<void>& SimpleFilterModifier::signal_blend_blur_changed()
+sigc::signal<void>& SimpleFilterModifier::signal_opacity_changed()
 {
-    return _signal_blend_blur_changed;
+    return _signal_opacity_changed;
 }
 
 const Glib::ustring SimpleFilterModifier::get_blend_mode()
@@ -75,9 +91,14 @@ void SimpleFilterModifier::set_blur_value(const double val)
     _blur.set_value(val);
 }
 
-void SimpleFilterModifier::set_blur_sensitive(const bool s)
+double SimpleFilterModifier::get_opacity_value() const
+{
+    return _opacity.get_value();
+}
+
+void SimpleFilterModifier::set_opacity_value(const double val)
 {
-    _blur.set_sensitive(s);
+    _opacity.set_value(val);
 }
 
 }
diff --git a/src/ui/widget/filter-effect-chooser.h b/src/ui/widget/filter-effect-chooser.h
index 0bcf97433..148f44d04 100644
--- a/src/ui/widget/filter-effect-chooser.h
+++ b/src/ui/widget/filter-effect-chooser.h
@@ -6,8 +6,9 @@
  *
  * Author:
  *   Nicholas Bishop <nicholasbishop@gmail.com>
+ *   Tavmjong Bah
  *
- * Copyright (C) 2007 Authors
+ * Copyright (C) 2007, 2017 Authors
  *
  * Released under GNU GPL, read the file 'COPYING' for more information
  */
@@ -23,40 +24,47 @@ namespace Inkscape {
 namespace UI {
 namespace Widget {
 
-/* Allows basic control over feBlend and feGaussianBlur effects,
-   with an option to use the full filter effect controls. */
+/* Allows basic control over feBlend and feGaussianBlur effects as well as opacity.
+ *  Common for Object, Layers, and Fill and Stroke dialogs.
+*/
 class SimpleFilterModifier : public Gtk::VBox
 {
 public:
     enum Flags {
-      NONE=0,
-      BLUR=1,
-      BLEND=2
+      NONE   = 0,
+      BLUR   = 1,
+      OPACITY= 2,
+      BLEND  = 4
     };
 
     SimpleFilterModifier(int flags);
 
-    sigc::signal<void>& signal_blend_blur_changed();
+    sigc::signal<void>& signal_blend_changed();
+    sigc::signal<void>& signal_blur_changed();
+    sigc::signal<void>& signal_opacity_changed();
 
     const Glib::ustring get_blend_mode();
     // Uses blend mode enum values, or -1 for a complex filter
     void set_blend_mode(const int);
 
     double get_blur_value() const;
-    void set_blur_value(const double);
-    void set_blur_sensitive(const bool);
-    Gtk::Label *get_blur_label() { return &_lb_blur; };
+    void   set_blur_value(const double);
+
+    double get_opacity_value() const;
+    void   set_opacity_value(const double);
 
 private:
     int _flags;
-    Gtk::HBox _hb_blend;
-    Gtk::HBox _hb_blur;
-    Gtk::Label _lb_blend, _lb_blur, _lb_blur_unit;
 
+    Gtk::HBox _hb_blend;
+    Gtk::Label _lb_blend;
     ComboBoxEnum<Inkscape::Filters::FilterBlendMode> _blend;
     SpinScale _blur;
+    SpinScale _opacity;
 
-    sigc::signal<void> _signal_blend_blur_changed;
+    sigc::signal<void> _signal_blend_changed;
+    sigc::signal<void> _signal_blur_changed;
+    sigc::signal<void> _signal_opacity_changed;
 };
 
 }
diff --git a/src/ui/widget/object-composite-settings.cpp b/src/ui/widget/object-composite-settings.cpp
index ae01c049b..161f5ba4f 100644
--- a/src/ui/widget/object-composite-settings.cpp
+++ b/src/ui/widget/object-composite-settings.cpp
@@ -33,42 +33,24 @@ namespace Widget {
 
 ObjectCompositeSettings::ObjectCompositeSettings(unsigned int verb_code, char const *history_prefix, int flags)
 : _verb_code(verb_code),
+  _blend_tag(Glib::ustring(history_prefix) + ":blend"),
   _blur_tag(Glib::ustring(history_prefix) + ":blur"),
   _opacity_tag(Glib::ustring(history_prefix) + ":opacity"),
-  _opacity_vbox(false, 0),
-  _opacity_scale(_("Opacity (%)"), 100.0, 0.0, 100.0, 1.0, 1.0, 1),
-  _fe_cb(flags),
-  _fe_vbox(false, 0),
+  _filter_modifier(flags),
   _blocked(false)
 {
-    set_name( "CompositeSettings");
+    set_name( "ObjectCompositeSettings");
 
     // Filter Effects
-    pack_start(_fe_vbox, false, false, 2);
-    _fe_vbox.pack_start(_fe_cb, false, false, 0);
-    _fe_cb.signal_blend_blur_changed().connect(sigc::mem_fun(*this, &ObjectCompositeSettings::_blendBlurValueChanged));
+    pack_start(_filter_modifier, false, false, 2);
 
-    // Opacity
-    pack_start(_opacity_vbox, false, false, 2);
-    _opacity_vbox.pack_start(_opacity_scale);
-
-    _opacity_scale.signal_value_changed().connect(sigc::mem_fun(*this, &ObjectCompositeSettings::_opacityValueChanged));
+    _filter_modifier.signal_blend_changed().connect(sigc::mem_fun(*this, &ObjectCompositeSettings::_blendBlurValueChanged));
+    _filter_modifier.signal_blur_changed().connect(sigc::mem_fun(*this, &ObjectCompositeSettings::_blendBlurValueChanged));
+    _filter_modifier.signal_opacity_changed().connect(sigc::mem_fun(*this, &ObjectCompositeSettings::_opacityValueChanged));
 
     SPDesktop *desktop = SP_ACTIVE_DESKTOP;
-    _opacity_scale.set_focuswidget(GTK_WIDGET(desktop->canvas));
-
-    /* SizeGroup keeps the blur and opacity labels aligned in Fill & Stroke dlg */
-/*
-    GtkSizeGroup *labels = gtk_size_group_new(GTK_SIZE_GROUP_HORIZONTAL);
-    gtk_size_group_add_widget(labels, GTK_WIDGET(_opacity_label.gobj()));
-    gtk_size_group_add_widget(labels, GTK_WIDGET(_fe_cb.get_blur_label()->gobj()));
-*/
 
     show_all_children();
-
-    // These signals don't properly detect change in desktop, rely on owner dialog to call setSubject() from setTargetDesktop()
-    //_desktop_activated = g_signal_connect ( G_OBJECT (INKSCAPE), "activate_desktop", G_CALLBACK (&ObjectCompositeSettings::_on_desktop_activate), this );
-    //_desktop_activated = g_signal_connect ( G_OBJECT (INKSCAPE), "deactivate_desktop", G_CALLBACK (&ObjectCompositeSettings::_on_desktop_deactivate), this );
 }
 
 ObjectCompositeSettings::~ObjectCompositeSettings() {
@@ -84,6 +66,12 @@ void ObjectCompositeSettings::setSubject(StyleSubject *subject) {
     }
 }
 
+// We get away with sharing one callback for blend and blur as this is used by
+//  * the Layers dialog where only one layer can be selected at a time,
+//  * the Fill and Stroke dialog where only blur is used.
+// If both blend and blur are used in a dialog where more than one object can
+// be selected then this should be split into separate functions for blend and
+// blur (like in the Objects dialog).
 void
 ObjectCompositeSettings::_blendBlurValueChanged()
 {
@@ -108,12 +96,12 @@ ObjectCompositeSettings::_blendBlurValueChanged()
     double radius;
     if (bbox) {
         double perimeter = bbox->dimensions()[Geom::X] + bbox->dimensions()[Geom::Y];   // fixme: this is only half the perimeter, is that correct?
-        radius = _fe_cb.get_blur_value() * perimeter / 400;
+        radius = _filter_modifier.get_blur_value() * perimeter / 400;
     } else {
         radius = 0;
     }
 
-    const Glib::ustring blendmode = _fe_cb.get_blend_mode();
+    const Glib::ustring blendmode = _filter_modifier.get_blend_mode();
 
     //apply created filter to every selected item
     std::vector<SPObject*> sel = _subject->list();
@@ -148,7 +136,7 @@ ObjectCompositeSettings::_blendBlurValueChanged()
     }
 
     DocumentUndo::maybeDone(document, _blur_tag.c_str(), _verb_code,
-                            _("Change blur"));
+                            _("Change blur/blend filter"));
 
     // resume interruptibility
     //sp_canvas_end_forced_full_redraws(desktop->getCanvas());
@@ -172,15 +160,10 @@ ObjectCompositeSettings::_opacityValueChanged()
         return;
     _blocked = true;
 
-    // FIXME: fix for GTK breakage, see comment in SelectedStyle::on_opacity_changed; here it results in crash 1580903
-    // UPDATE: crash fixed in GTK+ 2.10.7 (bug 374378), remove this as soon as it's reasonably common
-    // (though this only fixes the crash, not the multiple change events)
-    //sp_canvas_force_full_redraw_after_interruptions(desktop->getCanvas(), 0);
-
     SPCSSAttr *css = sp_repr_css_attr_new ();
 
     Inkscape::CSSOStringStream os;
-    os << CLAMP (_opacity_scale.get_adjustment()->get_value() / 100, 0.0, 1.0);
+    os << CLAMP (_filter_modifier.get_opacity_value() / 100, 0.0, 1.0);
     sp_repr_css_set_property (css, "opacity", os.str().c_str());
 
     _subject->setCSS(css);
@@ -216,14 +199,11 @@ ObjectCompositeSettings::_subjectChanged() {
 
     switch (result) {
         case QUERY_STYLE_NOTHING:
-            _opacity_vbox.set_sensitive(false);
-            // gtk_widget_set_sensitive (opa, FALSE);
             break;
         case QUERY_STYLE_SINGLE:
         case QUERY_STYLE_MULTIPLE_AVERAGED: // TODO: treat this slightly differently
         case QUERY_STYLE_MULTIPLE_SAME:
-            _opacity_vbox.set_sensitive(true);
-            _opacity_scale.get_adjustment()->set_value(100 * SP_SCALE24_TO_FLOAT(query.opacity.value));
+            _filter_modifier.set_opacity_value(100 * SP_SCALE24_TO_FLOAT(query.opacity.value));
             break;
     }
 
@@ -231,16 +211,13 @@ ObjectCompositeSettings::_subjectChanged() {
     const int blend_result = _subject->queryStyle(&query, QUERY_STYLE_PROPERTY_BLEND);
     switch(blend_result) {
         case QUERY_STYLE_NOTHING:
-            _fe_cb.set_sensitive(false);
             break;
         case QUERY_STYLE_SINGLE:
         case QUERY_STYLE_MULTIPLE_SAME:
-            _fe_cb.set_blend_mode(query.filter_blend_mode.value);
-            _fe_cb.set_sensitive(true);
+            _filter_modifier.set_blend_mode(query.filter_blend_mode.value);
             break;
         case QUERY_STYLE_MULTIPLE_DIFFERENT:
             // TODO: set text
-            _fe_cb.set_sensitive(false);
             break;
     }
 
@@ -248,7 +225,7 @@ ObjectCompositeSettings::_subjectChanged() {
         int blur_result = _subject->queryStyle(&query, QUERY_STYLE_PROPERTY_BLUR);
         switch (blur_result) {
             case QUERY_STYLE_NOTHING: //no blurring
-                _fe_cb.set_blur_sensitive(false);
+                _filter_modifier.set_blur_value(0);
                 break;
             case QUERY_STYLE_SINGLE:
             case QUERY_STYLE_MULTIPLE_AVERAGED:
@@ -256,16 +233,23 @@ ObjectCompositeSettings::_subjectChanged() {
                 Geom::OptRect bbox = _subject->getBounds(SPItem::GEOMETRIC_BBOX);
                 if (bbox) {
                     double perimeter = bbox->dimensions()[Geom::X] + bbox->dimensions()[Geom::Y];   // fixme: this is only half the perimeter, is that correct?
-                    _fe_cb.set_blur_sensitive(true);
                     //update blur widget value
                     float radius = query.filter_gaussianBlur_deviation.value;
                     float percent = radius * 400 / perimeter; // so that for a square, 100% == half side
-                    _fe_cb.set_blur_value(percent);
+                    _filter_modifier.set_blur_value(percent);
                 }
                 break;
         }
     }
 
+    // If we have nothing selected, disable dialog.
+    if (result       == QUERY_STYLE_NOTHING &&
+        blend_result == QUERY_STYLE_NOTHING ) {
+        _filter_modifier.set_sensitive( false );
+    } else {
+        _filter_modifier.set_sensitive( true );
+    }
+
     _blocked = false;
 }
 
diff --git a/src/ui/widget/object-composite-settings.h b/src/ui/widget/object-composite-settings.h
index eff1ba800..9e810bc00 100644
--- a/src/ui/widget/object-composite-settings.h
+++ b/src/ui/widget/object-composite-settings.h
@@ -18,7 +18,6 @@
 #include <glibmm/ustring.h>
 
 #include "ui/widget/filter-effect-chooser.h"
-#include "ui/widget/spinbutton.h"
 
 class SPDesktop;
 struct InkscapeApplication;
@@ -42,16 +41,13 @@ public:
 
 private:
     unsigned int    _verb_code;
+    Glib::ustring   _blend_tag;
     Glib::ustring   _blur_tag;
     Glib::ustring   _opacity_tag;
 
-    Gtk::VBox       _opacity_vbox;
-    SpinScale       _opacity_scale;
-
     StyleSubject *_subject;
 
-    SimpleFilterModifier _fe_cb;
-    Gtk::VBox       _fe_vbox;
+    SimpleFilterModifier _filter_modifier;
 
     bool _blocked;
     gulong _desktop_activated;