Update to trunk r13638

(bzr r13341.1.286)

7 files changed, 354 insertions, 230 deletions

diff --git a/src/ui/clipboard.cpp b/src/ui/clipboard.cpp
index 40500cf15..931a295d8 100644
--- a/src/ui/clipboard.cpp
+++ b/src/ui/clipboard.cpp
@@ -54,6 +54,7 @@
 #include <2geom/transforms.h>
 #include "box3d.h"
 #include "gradient-drag.h"
+#include "sp-marker.h"
 #include "sp-item.h"
 #include "sp-item-transform.h" // for sp_item_scale_rel, used in _pasteSize
 #include "sp-path.h"
@@ -505,12 +506,15 @@ bool ClipboardManagerImpl::pasteSize(SPDesktop *desktop, bool separately, bool a
         // resize each object in the selection
         if (separately) {
             for (GSList *i = const_cast<GSList*>(selection->itemList()) ; i ; i = i->next) {
-                SPItem *item = SP_ITEM(i->data);
-                Geom::OptRect obj_size = item->desktopVisualBounds();
-                if ( !obj_size ) {
-                    continue;
+                SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(i->data));
+                if (item) {
+                    Geom::OptRect obj_size = item->desktopVisualBounds();
+                    if ( obj_size ) {
+                        sp_item_scale_rel(item, _getScale(desktop, min, max, *obj_size, apply_x, apply_y));
+                    }
+                } else {
+                    g_assert_not_reached();
                 }
-                sp_item_scale_rel(item, _getScale(desktop, min, max, *obj_size, apply_x, apply_y));
             }
         }
         // resize the selection as a whole
@@ -640,7 +644,12 @@ void ClipboardManagerImpl::_copySelection(Inkscape::Selection *selection)
     GSList const *items = selection->itemList();
     // copy the defs used by all items
     for (GSList *i = const_cast<GSList *>(items) ; i != NULL ; i = i->next) {
-        _copyUsedDefs(SP_ITEM (i->data));
+        SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(i->data));
+        if (item) {
+            _copyUsedDefs(item);
+        } else {
+            g_assert_not_reached();
+        }
     }
 
     // copy the representation of the items
@@ -648,36 +657,38 @@ void ClipboardManagerImpl::_copySelection(Inkscape::Selection *selection)
     sorted_items = g_slist_sort(sorted_items, (GCompareFunc) sp_object_compare_position);
 
     for (GSList *i = sorted_items ; i ; i = i->next) {
-        if (!SP_IS_ITEM(i->data)) {
-            continue;
+        SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(i->data));
+        if (item) {
+            Inkscape::XML::Node *obj = item->getRepr();
+            Inkscape::XML::Node *obj_copy = _copyNode(obj, _doc, _root);
+
+            // copy complete inherited style
+            SPCSSAttr *css = sp_repr_css_attr_inherited(obj, "style");
+            sp_repr_css_set(obj_copy, css, "style");
+            sp_repr_css_attr_unref(css);
+
+            // write the complete accumulated transform passed to us
+            // (we're dealing with unattached representations, so we write to their attributes
+            // instead of using sp_item_set_transform)
+            gchar *transform_str = sp_svg_transform_write(item->i2doc_affine());
+            obj_copy->setAttribute("transform", transform_str);
+            g_free(transform_str);
         }
-        Inkscape::XML::Node *obj = reinterpret_cast<SPObject *>(i->data)->getRepr();
-        Inkscape::XML::Node *obj_copy = _copyNode(obj, _doc, _root);
-
-        // copy complete inherited style
-        SPCSSAttr *css = sp_repr_css_attr_inherited(obj, "style");
-        sp_repr_css_set(obj_copy, css, "style");
-        sp_repr_css_attr_unref(css);
-
-        // write the complete accumulated transform passed to us
-        // (we're dealing with unattached representations, so we write to their attributes
-        // instead of using sp_item_set_transform)
-        gchar *transform_str = sp_svg_transform_write(SP_ITEM(i->data)->i2doc_affine());
-        obj_copy->setAttribute("transform", transform_str);
-        g_free(transform_str);
     }
 
     // copy style for Paste Style action
     if (sorted_items) {
-        if (SP_IS_ITEM(sorted_items->data)) {
-            SPCSSAttr *style = take_style_from_item((SPItem *) sorted_items->data);
+        SPObject *object = static_cast<SPObject *>(sorted_items->data);
+        SPItem *item = dynamic_cast<SPItem *>(object);
+        if (item) {
+            SPCSSAttr *style = take_style_from_item(item);
             sp_repr_css_set(_clipnode, style, "style");
             sp_repr_css_attr_unref(style);
         }
 
         // copy path effect from the first path
-        if (SP_IS_OBJECT(sorted_items->data)) {
-            gchar const *effect = reinterpret_cast<SPObject *>(sorted_items->data)->getRepr()->attribute("inkscape:path-effect");
+        if (object) {
+            gchar const *effect =object->getRepr()->attribute("inkscape:path-effect");
             if (effect) {
                 _clipnode->setAttribute("inkscape:path-effect", effect);
             }
@@ -704,35 +715,38 @@ void ClipboardManagerImpl::_copyUsedDefs(SPItem *item)
 
     if (style && (style->fill.isPaintserver())) {
         SPPaintServer *server = item->style->getFillPaintServer();
-        if ( SP_IS_LINEARGRADIENT(server) || SP_IS_RADIALGRADIENT(server) ) {
-            _copyGradient(SP_GRADIENT(server));
+        if ( dynamic_cast<SPLinearGradient *>(server) || dynamic_cast<SPRadialGradient *>(server) ) {
+            _copyGradient(dynamic_cast<SPGradient *>(server));
         }
-        if ( SP_IS_PATTERN(server) ) {
-            _copyPattern(SP_PATTERN(server));
+        SPPattern *pattern = dynamic_cast<SPPattern *>(server);
+        if ( pattern ) {
+            _copyPattern(pattern);
         }
     }
     if (style && (style->stroke.isPaintserver())) {
         SPPaintServer *server = item->style->getStrokePaintServer();
-        if ( SP_IS_LINEARGRADIENT(server) || SP_IS_RADIALGRADIENT(server) ) {
-            _copyGradient(SP_GRADIENT(server));
+        if ( dynamic_cast<SPLinearGradient *>(server) || dynamic_cast<SPRadialGradient *>(server) ) {
+            _copyGradient(dynamic_cast<SPGradient *>(server));
         }
-        if ( SP_IS_PATTERN(server) ) {
-            _copyPattern(SP_PATTERN(server));
+        SPPattern *pattern = dynamic_cast<SPPattern *>(server);
+        if ( pattern ) {
+            _copyPattern(pattern);
         }
     }
 
     // For shapes, copy all of the shape's markers
-    if (SP_IS_SHAPE(item)) {
-        SPShape *shape = SP_SHAPE (item);
+    SPShape *shape = dynamic_cast<SPShape *>(item);
+    if (shape) {
         for (int i = 0 ; i < SP_MARKER_LOC_QTY ; i++) {
             if (shape->_marker[i]) {
                 _copyNode(shape->_marker[i]->getRepr(), _doc, _defs);
             }
         }
     }
+
     // For lpe items, copy lpe stack if applicable
-    if (SP_IS_LPE_ITEM(item)) {
-        SPLPEItem *lpeitem = SP_LPE_ITEM (item);
+    SPLPEItem *lpeitem = dynamic_cast<SPLPEItem *>(item);
+    if (lpeitem) {
         if (lpeitem->hasPathEffect()) {
             for (PathEffectList::iterator it = lpeitem->path_effect_list->begin(); it != lpeitem->path_effect_list->end(); ++it)
             {
@@ -743,14 +757,24 @@ void ClipboardManagerImpl::_copyUsedDefs(SPItem *item)
             }
         }
     }
+
     // For 3D boxes, copy perspectives
-    if (SP_IS_BOX3D(item)) {
-        _copyNode(box3d_get_perspective(SP_BOX3D(item))->getRepr(), _doc, _defs);
+    {
+        SPBox3D *box = dynamic_cast<SPBox3D *>(item);
+        if (box) {
+            _copyNode(box3d_get_perspective(box)->getRepr(), _doc, _defs);
+        }
     }
+
     // Copy text paths
-    if (SP_IS_TEXT_TEXTPATH(item)) {
-        _copyTextPath(SP_TEXTPATH(item->firstChild()));
+    {
+        SPText *text = dynamic_cast<SPText *>(item);
+        SPTextPath *textpath = (text) ? dynamic_cast<SPTextPath *>(text->firstChild()) : NULL;
+        if (textpath) {
+            _copyTextPath(textpath);
+        }
     }
+
     // Copy clipping objects
     if (item->clip_ref){
         if (item->clip_ref->getObject()) {
@@ -764,8 +788,9 @@ void ClipboardManagerImpl::_copyUsedDefs(SPItem *item)
             _copyNode(mask->getRepr(), _doc, _defs);
             // recurse into the mask for its gradients etc.
             for (SPObject *o = mask->children ; o != NULL ; o = o->next) {
-                if (SP_IS_ITEM(o)) {
-                    _copyUsedDefs(SP_ITEM(o));
+                SPItem *childItem = dynamic_cast<SPItem *>(o);
+                if (childItem) {
+                    _copyUsedDefs(childItem);
                 }
             }
         }
@@ -774,15 +799,16 @@ void ClipboardManagerImpl::_copyUsedDefs(SPItem *item)
     // Copy filters
     if (style->getFilter()) {
         SPObject *filter = style->getFilter();
-        if (SP_IS_FILTER(filter)) {
+        if (dynamic_cast<SPFilter *>(filter)) {
             _copyNode(filter->getRepr(), _doc, _defs);
         }
     }
 
     // recurse
     for (SPObject *o = item->children ; o != NULL ; o = o->next) {
-        if (SP_IS_ITEM(o)) {
-            _copyUsedDefs(SP_ITEM(o));
+        SPItem *childItem = dynamic_cast<SPItem *>(o);
+        if (childItem) {
+            _copyUsedDefs(childItem);
         }
     }
 }
@@ -817,10 +843,10 @@ void ClipboardManagerImpl::_copyPattern(SPPattern *pattern)
 
         // items in the pattern may also use gradients and other patterns, so recurse
         for ( SPObject *child = pattern->firstChild() ; child ; child = child->getNext() ) {
-            if (!SP_IS_ITEM (child)) {
-                continue;
+            SPItem *childItem = dynamic_cast<SPItem *>(child);
+            if (childItem) {
+                _copyUsedDefs(childItem);
             }
-            _copyUsedDefs(SP_ITEM(child));
         }
         if (pattern->ref){
             pattern = pattern->ref->getObject();
@@ -939,13 +965,13 @@ void ClipboardManagerImpl::_applyPathEffect(SPItem *item, gchar const *effectsta
     if ( item == NULL ) {
         return;
     }
-    if ( SP_IS_RECT(item) ) {
+    if ( dynamic_cast<SPRect *>(item) ) {
         return;
     }
 
-    if (SP_IS_LPE_ITEM(item))
+    SPLPEItem *lpeitem = dynamic_cast<SPLPEItem *>(item);
+    if (lpeitem)
     {
-        SPLPEItem *lpeitem = SP_LPE_ITEM(item);
         // for each effect in the stack, check if we need to fork it before adding it to the item
         lpeitem->forkPathEffectsIfNecessary(1);
 
diff --git a/src/ui/dialog/aboutbox.cpp b/src/ui/dialog/aboutbox.cpp
index 7212fa372..50b35ca2f 100644
--- a/src/ui/dialog/aboutbox.cpp
+++ b/src/ui/dialog/aboutbox.cpp
@@ -452,13 +452,13 @@ void AboutBox::initStrings() {
      */          
     gchar const *allTranslators =
 "3ARRANO.com <3arrano@3arrano.com>, 2005.\n"
-"Adib Taraben <theadib@gmail.com>, 2004.\n"
+"Adib Taraben <theadib@gmail.com>, 2004-2014.\n"
 "Alan Monfort <alan.monfort@free.fr>, 2009-2010.\n"
 "Alastair McKinstry <mckinstry@computer.org>, 2000.\n"
 "Aleksandar Urošević <urke@users.sourceforge.net>, 2004-2006.\n"
 "Alessio Frusciante <algol@firenze.linux.it>, 2002, 2003.\n"
 "Alexander Shopov <ash@contact.bg>, 2006.\n"
-"Alexandre Prokoudine <alexandre.prokoudine@gmail.com>, 2005, 2010-2013.\n"
+"Alexandre Prokoudine <alexandre.prokoudine@gmail.com>, 2005, 2010-2014.\n"
 "Alexey Remizov <alexey@remizov.pp.ru>, 2004.\n"
 "Ali Ghanavatian <ghanvatian.ali@gmail.com>, 2010.\n"
 "Álvaro Lopes <alvieboy@alvie.com>, 2001, 2002.\n"
@@ -503,7 +503,7 @@ void AboutBox::initStrings() {
 "Hleb Valoshka <375gnu@gmail.com>, 2008-2009.\n"
 "Hizkuntza Politikarako Sailburuordetza <hizkpol@ej-gv.es>, 2005.\n"
 "Ilia Penev <lichopicho@gmail.com>, 2006.\n"
-"Ivan Masár <helix84@centrum.sk>, 2006-2010. \n"
+"Ivan Masár <helix84@centrum.sk>, 2006-2014. \n"
 "Ivan Řihošek <irihosek@seznam.cz>, 2014.\n"
 "Iñaki Larrañaga <dooteo@euskalgnu.org>, 2006.\n"
 "Jānis Eisaks <jancs@dv.lv>, 2012-2014.\n"
@@ -537,7 +537,7 @@ void AboutBox::initStrings() {
 "Mahesh subedi <submanesh@hotmail.com>, 2006.\n"
 "Martin Srebotnjak, <miles@filmsi.net>, 2005, 2010.\n"
 "Masatake YAMATO <jet@gyve.org>, 2002.\n"
-"Masato Hashimoto <cabezon.hashimoto@gmail.com>, 2009-2012.\n"
+"Masato Hashimoto <cabezon.hashimoto@gmail.com>, 2009-2014.\n"
 "Matiphas <matiphas _a_ free _point_ fr>, 2004-2006.\n"
 "Mattias Hultgren <mattias_hultgren@tele2.se>, 2005, 2006.\n"
 "Maxim Dziumanenko <mvd@mylinux.com.ua>, 2004.\n"
@@ -553,7 +553,7 @@ void AboutBox::initStrings() {
 "Przemysław Loesch <p_loesch@poczta.onet.pl>, 2005.\n"
 "Quico Llach <quico@softcatala.org>, 2000. Traducció sodipodi.\n"
 "Raymond Ostertag <raymond@linuxgraphic.org>, 2002, 2003.\n"
-"Riku Leino <tsoots@gmail.com>, 2006.\n"
+"Riku Leino <tsoots@gmail.com>, 2006-2011.\n"
 "Rune Rønde Laursen <runerl@skjoldhoej.dk>, 2006.\n"
 "Ruud Steltenpool <svg@steltenpower.com>, 2006.\n"
 "Serdar Soytetir <sendirom@gmail.com>, 2005.\n"
@@ -569,9 +569,11 @@ void AboutBox::initStrings() {
 "Thiago Pimentel <thiago.merces@gmail.com>, 2006.\n"
 "Toshifumi Sato <sato@centrosystem.com>, 2005.\n"
 "Jon South <striker@lunar-linux.org>, 2006. \n"
-"Uwe Schöler <oss@oss-marketplace.com>, 2006-2013.\n"
+"Uwe Schöler <oss@oss-marketplace.com>, 2006-2014.\n"
 "Valek Filippov <frob@df.ru>, 2000, 2003.\n"
 "Victor Dachev <vdachev@gmail.com>, 2006.\n"
+"Victor Westmann <victor.westmann@gmail.com>, 2011, 2014.\n"
+"Ville Pätsi, 2013.\n"
 "Vincent van Adrighem <V.vanAdrighem@dirck.mine.nu>, 2003.\n"
 "Vital Khilko <dojlid@mova.org>, 2003.\n"
 "Vitaly Lipatov <lav@altlinux.ru>, 2002, 2004.\n"
@@ -584,7 +586,7 @@ void AboutBox::initStrings() {
 "Yaron Shahrabani <sh.yaron@gmail.com>, 2009.\n"
 "Yukihiro Nakai <nakai@gnome.gr.jp>, 2000, 2003.\n"
 "Yuri Beznos <zhiz0id@gmail.com>, 2006.\n"
-"Yuri Chornoivan <yurchor@ukr.net>, 2007-2013.\n"
+"Yuri Chornoivan <yurchor@ukr.net>, 2007-2014.\n"
 "Yuri Syrota <rasta@renome.rovno.ua>, 2000.\n"
 "Yves Guillou <yvesguillou@users.sourceforge.net>, 2004.\n"
 "Zdenko Podobný <zdpo@mailbox.sk>, 2003, 2004."
diff --git a/src/ui/object-edit.cpp b/src/ui/object-edit.cpp
index cc96727f8..ca550502d 100644
--- a/src/ui/object-edit.cpp
+++ b/src/ui/object-edit.cpp
@@ -6,6 +6,7 @@
  *   Mitsuru Oka
  *   Maximilian Albert <maximilian.albert@gmail.com>
  *   Abhishek Sharma
+ *   Jon A. Cruz <jon@joncruz.org>
  *
  * Licensed under GNU GPL
  */
@@ -42,11 +43,11 @@
 
 namespace {
 
-static KnotHolder *sp_lpe_knot_holder(SPItem *item, SPDesktop *desktop)
+static KnotHolder *sp_lpe_knot_holder(SPLPEItem *item, SPDesktop *desktop)
 {
     KnotHolder *knot_holder = new KnotHolder(desktop, item, NULL);
 
-    Inkscape::LivePathEffect::Effect *effect = SP_LPE_ITEM(item)->getCurrentLPE();
+    Inkscape::LivePathEffect::Effect *effect = item->getCurrentLPE();
     effect->addHandles(knot_holder, desktop, item);
 
     return knot_holder;
@@ -61,29 +62,33 @@ KnotHolder *createKnotHolder(SPItem *item, SPDesktop *desktop)
 {
     KnotHolder *knotholder = NULL;
 
-    if (SP_IS_LPE_ITEM(item) &&
-        SP_LPE_ITEM(item)->getCurrentLPE() &&
-        SP_LPE_ITEM(item)->getCurrentLPE()->isVisible() &&
-        SP_LPE_ITEM(item)->getCurrentLPE()->providesKnotholder()) {
-        knotholder = sp_lpe_knot_holder(item, desktop);
-    } else if (SP_IS_RECT(item)) {
+    SPLPEItem *lpe = dynamic_cast<SPLPEItem *>(item);
+    if (lpe &&
+        lpe->getCurrentLPE() &&
+        lpe->getCurrentLPE()->isVisible() &&
+        lpe->getCurrentLPE()->providesKnotholder()) {
+        knotholder = sp_lpe_knot_holder(lpe, desktop);
+    } else if (dynamic_cast<SPRect *>(item)) {
         knotholder = new RectKnotHolder(desktop, item, NULL);
-    } else if (SP_IS_BOX3D(item)) {
+    } else if (dynamic_cast<SPBox3D *>(item)) {
         knotholder = new Box3DKnotHolder(desktop, item, NULL);
-    } else if (SP_IS_GENERICELLIPSE(item)) {
+    } else if (dynamic_cast<SPGenericEllipse *>(item)) {
         knotholder = new ArcKnotHolder(desktop, item, NULL);
-    } else if (SP_IS_STAR(item)) {
+    } else if (dynamic_cast<SPStar *>(item)) {
         knotholder = new StarKnotHolder(desktop, item, NULL);
-    } else if (SP_IS_SPIRAL(item)) {
+    } else if (dynamic_cast<SPSpiral *>(item)) {
         knotholder = new SpiralKnotHolder(desktop, item, NULL);
-    } else if (SP_IS_OFFSET(item)) {
+    } else if (dynamic_cast<SPOffset *>(item)) {
         knotholder = new OffsetKnotHolder(desktop, item, NULL);
-    } else if (SP_IS_FLOWTEXT(item) && SP_FLOWTEXT(item)->has_internal_frame()) {
-        knotholder = new FlowtextKnotHolder(desktop, SP_FLOWTEXT(item)->get_frame(NULL), NULL);
-    } else if ((item->style->fill.isPaintserver() && SP_IS_PATTERN(item->style->getFillPaintServer())) ||
-               (item->style->stroke.isPaintserver() && SP_IS_PATTERN(item->style->getStrokePaintServer()))) {
-        knotholder = new KnotHolder(desktop, item, NULL);
-        knotholder->add_pattern_knotholder();
+    } else {
+        SPFlowtext *flowtext = dynamic_cast<SPFlowtext *>(item);
+        if (flowtext && flowtext->has_internal_frame()) {
+            knotholder = new FlowtextKnotHolder(desktop, flowtext->get_frame(NULL), NULL);
+        } else if ((item->style->fill.isPaintserver() && dynamic_cast<SPPattern *>(item->style->getFillPaintServer())) ||
+                   (item->style->stroke.isPaintserver() && dynamic_cast<SPPattern *>(item->style->getStrokePaintServer()))) {
+            knotholder = new KnotHolder(desktop, item, NULL);
+            knotholder->add_pattern_knotholder();
+        }
     }
 
     return knotholder;
@@ -130,7 +135,8 @@ public:
 Geom::Point
 RectKnotHolderEntityRX::knot_get() const
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     return Geom::Point(rect->x.computed + rect->width.computed - rect->rx.computed, rect->y.computed);
 }
@@ -138,7 +144,8 @@ RectKnotHolderEntityRX::knot_get() const
 void
 RectKnotHolderEntityRX::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, unsigned int state)
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     //In general we cannot just snap this radius to an arbitrary point, as we have only a single
     //degree of freedom. For snapping to an arbitrary point we need two DOF. If we're going to snap
@@ -157,13 +164,14 @@ RectKnotHolderEntityRX::knot_set(Geom::Point const &p, Geom::Point const &/*orig
 
     update_knot();
 
-    (static_cast<SPObject*>(rect))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    rect->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 void
 RectKnotHolderEntityRX::knot_click(unsigned int state)
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     if (state & GDK_SHIFT_MASK) {
         /* remove rounding from rectangle */
@@ -179,7 +187,8 @@ RectKnotHolderEntityRX::knot_click(unsigned int state)
 Geom::Point
 RectKnotHolderEntityRY::knot_get() const
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     return Geom::Point(rect->x.computed + rect->width.computed, rect->y.computed + rect->ry.computed);
 }
@@ -187,7 +196,8 @@ RectKnotHolderEntityRY::knot_get() const
 void
 RectKnotHolderEntityRY::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, unsigned int state)
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     //In general we cannot just snap this radius to an arbitrary point, as we have only a single
     //degree of freedom. For snapping to an arbitrary point we need two DOF. If we're going to snap
@@ -215,13 +225,14 @@ RectKnotHolderEntityRY::knot_set(Geom::Point const &p, Geom::Point const &/*orig
 
     update_knot();
 
-    (static_cast<SPObject *>(rect))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    rect->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 void
 RectKnotHolderEntityRY::knot_click(unsigned int state)
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     if (state & GDK_SHIFT_MASK) {
         /* remove rounding */
@@ -251,7 +262,8 @@ static void sp_rect_clamp_radii(SPRect *rect)
 Geom::Point
 RectKnotHolderEntityWH::knot_get() const
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     return Geom::Point(rect->x.computed + rect->width.computed, rect->y.computed + rect->height.computed);
 }
@@ -259,7 +271,8 @@ RectKnotHolderEntityWH::knot_get() const
 void
 RectKnotHolderEntityWH::set_internal(Geom::Point const &p, Geom::Point const &origin, unsigned int state)
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     Geom::Point s = p;
 
@@ -325,7 +338,7 @@ RectKnotHolderEntityWH::set_internal(Geom::Point const &p, Geom::Point const &or
 
     sp_rect_clamp_radii(rect);
 
-    (static_cast<SPObject *>(rect))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    rect->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 void
@@ -338,7 +351,8 @@ RectKnotHolderEntityWH::knot_set(Geom::Point const &p, Geom::Point const &origin
 Geom::Point
 RectKnotHolderEntityXY::knot_get() const
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     return Geom::Point(rect->x.computed, rect->y.computed);
 }
@@ -346,7 +360,8 @@ RectKnotHolderEntityXY::knot_get() const
 void
 RectKnotHolderEntityXY::knot_set(Geom::Point const &p, Geom::Point const &origin, unsigned int state)
 {
-    SPRect *rect = SP_RECT(item);
+    SPRect *rect = dynamic_cast<SPRect *>(item);
+    g_assert(rect != NULL);
 
     // opposite corner (unmoved)
     gdouble opposite_x = (rect->x.computed + rect->width.computed);
@@ -426,7 +441,7 @@ RectKnotHolderEntityXY::knot_set(Geom::Point const &p, Geom::Point const &origin
 
     update_knot();
 
-    (static_cast<SPObject *>(rect))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    rect->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 RectKnotHolder::RectKnotHolder(SPDesktop *desktop, SPItem *item, SPKnotHolderReleasedFunc relhandler) :
@@ -479,7 +494,12 @@ public:
 Geom::Point
 Box3DKnotHolderEntity::knot_get_generic(SPItem *item, unsigned int knot_id) const
 {
-    return box3d_get_corner_screen(SP_BOX3D(item), knot_id);
+    SPBox3D *box = dynamic_cast<SPBox3D *>(item);
+    if (box) {
+        return box3d_get_corner_screen(box, knot_id);
+    } else {
+        return Geom::Point(); // TODO investigate proper fallback
+    }
 }
 
 void
@@ -488,7 +508,8 @@ Box3DKnotHolderEntity::knot_set_generic(SPItem *item, unsigned int knot_id, Geom
     Geom::Point const s = snap_knot_position(new_pos, state);
 
     g_assert(item != NULL);
-    SPBox3D *box = SP_BOX3D(item);
+    SPBox3D *box = dynamic_cast<SPBox3D *>(item);
+    g_assert(box != NULL);
     Geom::Affine const i2dt (item->i2dt_affine ());
 
     Box3D::Axis movement;
@@ -608,7 +629,12 @@ Box3DKnotHolderEntity7::knot_get() const
 Geom::Point
 Box3DKnotHolderEntityCenter::knot_get() const
 {
-    return box3d_get_center_screen(SP_BOX3D(item));
+    SPBox3D *box = dynamic_cast<SPBox3D *>(item);
+    if (box) {
+        return box3d_get_center_screen(box);
+    } else {
+        return Geom::Point(); // TODO investigate proper fallback
+    }
 }
 
 void
@@ -664,10 +690,11 @@ Box3DKnotHolderEntityCenter::knot_set(Geom::Point const &new_pos, Geom::Point co
 {
     Geom::Point const s = snap_knot_position(new_pos, state);
 
-    SPBox3D *box = SP_BOX3D(item);
+    SPBox3D *box = dynamic_cast<SPBox3D *>(item);
+    g_assert(box != NULL);
     Geom::Affine const i2dt (item->i2dt_affine ());
 
-    box3d_set_center (SP_BOX3D(item), s * i2dt, origin * i2dt, !(state & GDK_SHIFT_MASK) ? Box3D::XY : Box3D::Z,
+    box3d_set_center(box, s * i2dt, origin * i2dt, !(state & GDK_SHIFT_MASK) ? Box3D::XY : Box3D::Z,
                       state & GDK_CONTROL_MASK);
 
     box3d_set_z_orders(box);
@@ -789,7 +816,8 @@ ArcKnotHolderEntityStart::knot_set(Geom::Point const &p, Geom::Point const &/*or
 {
     int snaps = Inkscape::Preferences::get()->getInt("/options/rotationsnapsperpi/value", 12);
 
-    SPGenericEllipse *arc = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *arc = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(arc != NULL);
 
     arc->setClosed(sp_genericellipse_side(arc, p) == -1);
 
@@ -809,7 +837,8 @@ ArcKnotHolderEntityStart::knot_set(Geom::Point const &p, Geom::Point const &/*or
 Geom::Point
 ArcKnotHolderEntityStart::knot_get() const
 {
-    SPGenericEllipse const *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse const *ge = dynamic_cast<SPGenericEllipse const *>(item);
+    g_assert(ge != NULL);
 
     return ge->getPointAtAngle(ge->start);
 }
@@ -817,11 +846,12 @@ ArcKnotHolderEntityStart::knot_get() const
 void
 ArcKnotHolderEntityStart::knot_click(unsigned int state)
 {
-    SPGenericEllipse *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *ge = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(ge != NULL);
 
     if (state & GDK_SHIFT_MASK) {
         ge->end = ge->start = 0;
-        (static_cast<SPObject *>(ge))->updateRepr();
+        ge->updateRepr();
     }
 }
 
@@ -830,7 +860,8 @@ ArcKnotHolderEntityEnd::knot_set(Geom::Point const &p, Geom::Point const &/*orig
 {
     int snaps = Inkscape::Preferences::get()->getInt("/options/rotationsnapsperpi/value", 12);
 
-    SPGenericEllipse *arc = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *arc = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(arc != NULL);
 
     arc->setClosed(sp_genericellipse_side(arc, p) == -1);
 
@@ -850,7 +881,8 @@ ArcKnotHolderEntityEnd::knot_set(Geom::Point const &p, Geom::Point const &/*orig
 Geom::Point
 ArcKnotHolderEntityEnd::knot_get() const
 {
-    SPGenericEllipse const *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse const *ge = dynamic_cast<SPGenericEllipse const *>(item);
+    g_assert(ge != NULL);
 
     return ge->getPointAtAngle(ge->end);
 }
@@ -859,11 +891,12 @@ ArcKnotHolderEntityEnd::knot_get() const
 void
 ArcKnotHolderEntityEnd::knot_click(unsigned int state)
 {
-    SPGenericEllipse *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *ge = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(ge != NULL);
 
     if (state & GDK_SHIFT_MASK) {
         ge->end = ge->start = 0;
-        (static_cast<SPObject *>(ge))->updateRepr();
+        ge->updateRepr();
     }
 }
 
@@ -871,7 +904,8 @@ ArcKnotHolderEntityEnd::knot_click(unsigned int state)
 void
 ArcKnotHolderEntityRX::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, unsigned int state)
 {
-    SPGenericEllipse *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *ge = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(ge != NULL);
 
     Geom::Point const s = snap_knot_position(p, state);
 
@@ -881,13 +915,14 @@ ArcKnotHolderEntityRX::knot_set(Geom::Point const &p, Geom::Point const &/*origi
         ge->ry.computed = ge->rx.computed;
     }
 
-    (static_cast<SPObject *>(item))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    item->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 Geom::Point
 ArcKnotHolderEntityRX::knot_get() const
 {
-    SPGenericEllipse const *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse const *ge = dynamic_cast<SPGenericEllipse const *>(item);
+    g_assert(ge != NULL);
 
     return (Geom::Point(ge->cx.computed, ge->cy.computed) -  Geom::Point(ge->rx.computed, 0));
 }
@@ -895,18 +930,20 @@ ArcKnotHolderEntityRX::knot_get() const
 void
 ArcKnotHolderEntityRX::knot_click(unsigned int state)
 {
-    SPGenericEllipse *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *ge = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(ge != NULL);
 
     if (state & GDK_CONTROL_MASK) {
         ge->ry.computed = ge->rx.computed;
-        (static_cast<SPObject *>(ge))->updateRepr();
+        ge->updateRepr();
     }
 }
 
 void
 ArcKnotHolderEntityRY::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, unsigned int state)
 {
-    SPGenericEllipse *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *ge = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(ge != NULL);
 
     Geom::Point const s = snap_knot_position(p, state);
 
@@ -916,13 +953,14 @@ ArcKnotHolderEntityRY::knot_set(Geom::Point const &p, Geom::Point const &/*origi
         ge->rx.computed = ge->ry.computed;
     }
 
-    (static_cast<SPObject *>(item))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    item->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 Geom::Point
 ArcKnotHolderEntityRY::knot_get() const
 {
-    SPGenericEllipse const *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse const *ge = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(ge != NULL);
 
     return (Geom::Point(ge->cx.computed, ge->cy.computed) -  Geom::Point(0, ge->ry.computed));
 }
@@ -930,11 +968,12 @@ ArcKnotHolderEntityRY::knot_get() const
 void
 ArcKnotHolderEntityRY::knot_click(unsigned int state)
 {
-    SPGenericEllipse *ge = SP_GENERICELLIPSE(item);
+    SPGenericEllipse *ge = dynamic_cast<SPGenericEllipse *>(item);
+    g_assert(ge != NULL);
 
     if (state & GDK_CONTROL_MASK) {
         ge->rx.computed = ge->ry.computed;
-        (static_cast<SPObject *>(ge))->updateRepr();
+        ge->updateRepr();
     }
 }
 
@@ -991,7 +1030,8 @@ public:
 void
 StarKnotHolderEntity1::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, unsigned int state)
 {
-    SPStar *star = SP_STAR(item);
+    SPStar *star = dynamic_cast<SPStar *>(item);
+    g_assert(star != NULL);
 
     Geom::Point const s = snap_knot_position(p, state);
 
@@ -1011,13 +1051,14 @@ StarKnotHolderEntity1::knot_set(Geom::Point const &p, Geom::Point const &/*origi
         star->arg[0]  = arg1;
         star->arg[1] += darg1;
     }
-    (static_cast<SPObject *>(star))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    star->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 void
 StarKnotHolderEntity2::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, unsigned int state)
 {
-    SPStar *star = SP_STAR(item);
+    SPStar *star = dynamic_cast<SPStar *>(item);
+    g_assert(star != NULL);
 
     Geom::Point const s = snap_knot_position(p, state);
 
@@ -1039,7 +1080,7 @@ StarKnotHolderEntity2::knot_set(Geom::Point const &p, Geom::Point const &/*origi
             star->r[1]   = L2(d);
             star->arg[1] = atan2(d);
         }
-        (static_cast<SPObject *>(star))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+        star->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
     }
 }
 
@@ -1048,7 +1089,8 @@ StarKnotHolderEntity1::knot_get() const
 {
     g_assert(item != NULL);
 
-    SPStar const *star = SP_STAR(item);
+    SPStar const *star = dynamic_cast<SPStar const *>(item);
+    g_assert(star != NULL);
 
     return sp_star_get_xy(star, SP_STAR_POINT_KNOT1, 0);
 
@@ -1059,7 +1101,8 @@ StarKnotHolderEntity2::knot_get() const
 {
     g_assert(item != NULL);
 
-    SPStar const *star = SP_STAR(item);
+    SPStar const *star = dynamic_cast<SPStar const *>(item);
+    g_assert(star != NULL);
 
     return sp_star_get_xy(star, SP_STAR_POINT_KNOT2, 0);
 }
@@ -1067,17 +1110,18 @@ StarKnotHolderEntity2::knot_get() const
 static void
 sp_star_knot_click(SPItem *item, unsigned int state)
 {
-    SPStar *star = SP_STAR(item);
+    SPStar *star = dynamic_cast<SPStar *>(item);
+    g_assert(star != NULL);
 
     if (state & GDK_MOD1_MASK) {
         star->randomized = 0;
-        (static_cast<SPObject *>(star))->updateRepr();
+        star->updateRepr();
     } else if (state & GDK_SHIFT_MASK) {
         star->rounded = 0;
-        (static_cast<SPObject *>(star))->updateRepr();
+        star->updateRepr();
     } else if (state & GDK_CONTROL_MASK) {
         star->arg[1] = star->arg[0] + M_PI / star->sides;
-        (static_cast<SPObject *>(star))->updateRepr();
+        star->updateRepr();
     }
 }
 
@@ -1096,7 +1140,8 @@ StarKnotHolderEntity2::knot_click(unsigned int state)
 StarKnotHolder::StarKnotHolder(SPDesktop *desktop, SPItem *item, SPKnotHolderReleasedFunc relhandler) :
     KnotHolder(desktop, item, relhandler)
 {
-    SPStar *star = SP_STAR(item);
+    SPStar *star = dynamic_cast<SPStar *>(item);
+    g_assert(item != NULL);
 
     StarKnotHolderEntity1 *entity1 = new StarKnotHolderEntity1();
     entity1->create(desktop, item, this, Inkscape::CTRL_TYPE_SHAPER,
@@ -1144,7 +1189,8 @@ SpiralKnotHolderEntityInner::knot_set(Geom::Point const &p, Geom::Point const &o
     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
     int snaps = prefs->getInt("/options/rotationsnapsperpi/value", 12);
 
-    SPSpiral *spiral = SP_SPIRAL(item);
+    SPSpiral *spiral = dynamic_cast<SPSpiral *>(item);
+    g_assert(spiral != NULL);
 
     gdouble   dx = p[Geom::X] - spiral->cx;
     gdouble   dy = p[Geom::Y] - spiral->cy;
@@ -1179,7 +1225,7 @@ SpiralKnotHolderEntityInner::knot_set(Geom::Point const &p, Geom::Point const &o
         spiral->t0 = CLAMP(spiral->t0, 0.0, 0.999);
     }
 
-    (static_cast<SPObject *>(spiral))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    spiral->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 /*
@@ -1193,7 +1239,8 @@ SpiralKnotHolderEntityOuter::knot_set(Geom::Point const &p, Geom::Point const &/
     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
     int snaps = prefs->getInt("/options/rotationsnapsperpi/value", 12);
 
-    SPSpiral *spiral = SP_SPIRAL(item);
+    SPSpiral *spiral = dynamic_cast<SPSpiral *>(item);
+    g_assert(spiral != NULL);
 
     gdouble  dx = p[Geom::X] - spiral->cx;
     gdouble  dy = p[Geom::Y] - spiral->cy;
@@ -1258,13 +1305,14 @@ SpiralKnotHolderEntityOuter::knot_set(Geom::Point const &p, Geom::Point const &/
         spiral->t0 = CLAMP(spiral->t0, 0.0, 0.999);
     }
 
-    (static_cast<SPObject *>(spiral))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    spiral->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 Geom::Point
 SpiralKnotHolderEntityInner::knot_get() const
 {
-    SPSpiral const *spiral = SP_SPIRAL(item);
+    SPSpiral const *spiral = dynamic_cast<SPSpiral const *>(item);
+    g_assert(spiral != NULL);
 
     return spiral->getXY(spiral->t0);
 }
@@ -1272,7 +1320,8 @@ SpiralKnotHolderEntityInner::knot_get() const
 Geom::Point
 SpiralKnotHolderEntityOuter::knot_get() const
 {
-    SPSpiral const *spiral = SP_SPIRAL(item);
+    SPSpiral const *spiral = dynamic_cast<SPSpiral const *>(item);
+    g_assert(spiral != NULL);
 
     return spiral->getXY(1.0);
 }
@@ -1280,14 +1329,15 @@ SpiralKnotHolderEntityOuter::knot_get() const
 void
 SpiralKnotHolderEntityInner::knot_click(unsigned int state)
 {
-    SPSpiral *spiral = SP_SPIRAL(item);
+    SPSpiral *spiral = dynamic_cast<SPSpiral *>(item);
+    g_assert(spiral != NULL);
 
     if (state & GDK_MOD1_MASK) {
         spiral->exp = 1;
-        (static_cast<SPObject *>(spiral))->updateRepr();
+        spiral->updateRepr();
     } else if (state & GDK_SHIFT_MASK) {
         spiral->t0 = 0;
-        (static_cast<SPObject *>(spiral))->updateRepr();
+        spiral->updateRepr();
     }
 }
 
@@ -1322,20 +1372,22 @@ public:
 void
 OffsetKnotHolderEntity::knot_set(Geom::Point const &p, Geom::Point const &/*origin*/, unsigned int /*state*/)
 {
-    SPOffset *offset = SP_OFFSET(item);
+    SPOffset *offset = dynamic_cast<SPOffset *>(item);
+    g_assert(offset != NULL);
 
     offset->rad = sp_offset_distance_to_original(offset, p);
     offset->knot = p;
     offset->knotSet = true;
 
-    (static_cast<SPObject *>(offset))->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    offset->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
 }
 
 
 Geom::Point
 OffsetKnotHolderEntity::knot_get() const
 {
-    SPOffset const *offset = SP_OFFSET(item);
+    SPOffset const *offset = dynamic_cast<SPOffset const *>(item);
+    g_assert(offset != NULL);
 
     Geom::Point np;
     sp_offset_top_point(offset,&np);
@@ -1365,7 +1417,8 @@ public:
 Geom::Point
 FlowtextKnotHolderEntity::knot_get() const
 {
-    SPRect const *rect = SP_RECT(item);
+    SPRect const *rect = dynamic_cast<SPRect const *>(item);
+    g_assert(rect != NULL);
 
     return Geom::Point(rect->x.computed + rect->width.computed, rect->y.computed + rect->height.computed);
 }
diff --git a/src/ui/tools-switch.cpp b/src/ui/tools-switch.cpp
index 048252788..47b9d2832 100644
--- a/src/ui/tools-switch.cpp
+++ b/src/ui/tools-switch.cpp
@@ -4,6 +4,7 @@
  * Authors:
  *   bulia byak <buliabyak@users.sf.net>
  *   Josh Andler <scislac@users.sf.net>
+ *   Jon A. Cruz <jon@joncruz.org>
  *
  * Copyright (C) 2003-2007 authors
  *
@@ -59,6 +60,8 @@
 
 #include "message-context.h"
 
+using Inkscape::UI::Tools::ToolBase;
+
 static char const *const tool_names[] = {
     NULL,
     "/tools/select",
@@ -130,9 +133,11 @@ int
 tools_isactive(SPDesktop *dt, unsigned num)
 {
     g_assert( num < G_N_ELEMENTS(tool_names) );
-    if (SP_IS_EVENT_CONTEXT(dt->event_context))
+    if (dynamic_cast<ToolBase *>(dt->event_context)) {
         return dt->event_context->pref_observer->observed_path == tool_names[num];
-    else return FALSE;
+    } else {
+        return FALSE;
+    }
 }
 
 int
@@ -159,27 +164,27 @@ tools_switch(SPDesktop *dt, int num)
 
 void tools_switch_by_item(SPDesktop *dt, SPItem *item, Geom::Point const p)
 {
-    if (SP_IS_RECT(item)) {
+    if (dynamic_cast<SPRect *>(item)) {
         tools_switch(dt, TOOLS_SHAPES_RECT);
-    } else if (SP_IS_BOX3D(item)) {
+    } else if (dynamic_cast<SPBox3D *>(item)) {
         tools_switch(dt, TOOLS_SHAPES_3DBOX);
-    } else if (SP_IS_GENERICELLIPSE(item)) {
+    } else if (dynamic_cast<SPGenericEllipse *>(item)) {
         tools_switch(dt, TOOLS_SHAPES_ARC);
-    } else if (SP_IS_STAR(item)) {
+    } else if (dynamic_cast<SPStar *>(item)) {
         tools_switch(dt, TOOLS_SHAPES_STAR);
-    } else if (SP_IS_SPIRAL(item)) {
+    } else if (dynamic_cast<SPSpiral *>(item)) {
         tools_switch(dt, TOOLS_SHAPES_SPIRAL);
-    } else if (SP_IS_PATH(item)) {
+    } else if (dynamic_cast<SPPath *>(item)) {
         if (Inkscape::UI::Tools::cc_item_is_connector(item)) {
             tools_switch(dt, TOOLS_CONNECTOR);
         }
         else {
             tools_switch(dt, TOOLS_NODES);
         }
-    } else if (SP_IS_TEXT(item) || SP_IS_FLOWTEXT(item))  {
+    } else if (dynamic_cast<SPText *>(item) || dynamic_cast<SPFlowtext *>(item))  {
         tools_switch(dt, TOOLS_TEXT);
-        sp_text_context_place_cursor_at (SP_TEXT_CONTEXT(dt->event_context), SP_OBJECT(item), p);
-    } else if (SP_IS_OFFSET(item))  {
+        sp_text_context_place_cursor_at (SP_TEXT_CONTEXT(dt->event_context), item, p);
+    } else if (dynamic_cast<SPOffset *>(item))  {
         tools_switch(dt, TOOLS_NODES);
     }
 }
diff --git a/src/ui/tools/select-tool.cpp b/src/ui/tools/select-tool.cpp
index 394b0b369..21459e5d0 100644
--- a/src/ui/tools/select-tool.cpp
+++ b/src/ui/tools/select-tool.cpp
@@ -264,15 +264,16 @@ sp_select_context_up_one_layer(SPDesktop *desktop)
     SPObject *const current_layer = desktop->currentLayer();
     if (current_layer) {
         SPObject *const parent = current_layer->parent;
+        SPGroup *current_group = dynamic_cast<SPGroup *>(current_layer);
         if ( parent
              && ( parent->parent
-                  || !( SP_IS_GROUP(current_layer)
-                        && ( SPGroup::LAYER
-                             == SP_GROUP(current_layer)->layerMode() ) ) ) )
+                  || !( current_group
+                        && ( SPGroup::LAYER == current_group->layerMode() ) ) ) )
         {
             desktop->setCurrentLayer(parent);
-            if (SP_IS_GROUP(current_layer) && SPGroup::LAYER != SP_GROUP(current_layer)->layerMode())
+            if (current_group && (SPGroup::LAYER != current_group->layerMode())) {
                 sp_desktop_selection(desktop)->set(current_layer);
+            }
         }
     }
 }
@@ -403,7 +404,8 @@ void SelectTool::sp_select_context_cycle_through_items(Inkscape::Selection *sele
     }
 
     Inkscape::DrawingItem *arenaitem;
-    SPItem *item = SP_ITEM(this->cycling_cur_item->data);
+    SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(cycling_cur_item->data));
+    g_assert(item != NULL);
 
     // Deactivate current item
     if (!g_list_find(this->cycling_items_selected_before, item) && selection->includes(item)) {
@@ -427,7 +429,8 @@ void SelectTool::sp_select_context_cycle_through_items(Inkscape::Selection *sele
 
     if (next) {
         this->cycling_cur_item = next;
-        item = SP_ITEM(this->cycling_cur_item->data);
+        item = dynamic_cast<SPItem *>(static_cast<SPObject *>(this->cycling_cur_item->data));
+        g_assert(item != NULL);
     }
 
     arenaitem = item->get_arenaitem(desktop->dkey);
@@ -442,8 +445,13 @@ void SelectTool::sp_select_context_cycle_through_items(Inkscape::Selection *sele
 
 void SelectTool::sp_select_context_reset_opacities() {
     for (GList *l = this->cycling_items; l != NULL; l = g_list_next(l)) {
-        Inkscape::DrawingItem *arenaitem = SP_ITEM(l->data)->get_arenaitem(this->desktop->dkey);
-        arenaitem->setOpacity(SP_SCALE24_TO_FLOAT(SP_ITEM(l->data)->style->opacity.value));
+        SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(l->data));
+        if (item) {
+            Inkscape::DrawingItem *arenaitem = item->get_arenaitem(desktop->dkey);
+            arenaitem->setOpacity(SP_SCALE24_TO_FLOAT(item->style->opacity.value));
+        } else {
+            g_assert_not_reached();
+        }
     }
 
     g_list_free(this->cycling_items);
@@ -475,8 +483,8 @@ bool SelectTool::root_handler(GdkEvent* event) {
                 if (!selection->isEmpty()) {
                     SPItem *clicked_item = static_cast<SPItem *>(selection->itemList()->data);
 
-                    if (SP_IS_GROUP(clicked_item) && !SP_IS_BOX3D(clicked_item)) { // enter group if it's not a 3D box
-                        desktop->setCurrentLayer(reinterpret_cast<SPObject *>(clicked_item));
+                    if (dynamic_cast<SPGroup *>(clicked_item) && !dynamic_cast<SPBox3D *>(clicked_item)) { // enter group if it's not a 3D box
+                        desktop->setCurrentLayer(clicked_item);
                         sp_desktop_selection(desktop)->clear();
                         this->dragging = false;
                         sp_event_context_discard_delayed_snap_event(this);
@@ -591,8 +599,11 @@ bool SelectTool::root_handler(GdkEvent* event) {
                             item_in_group = desktop->getItemAtPoint(Geom::Point(event->button.x, event->button.y), TRUE);
                             group_at_point = desktop->getGroupAtPoint(Geom::Point(event->button.x, event->button.y));
 
-                            if (SP_IS_LAYER(selection->single())) {
-                                group_at_point = SP_GROUP(selection->single());
+                            {
+                                SPGroup *selGroup = dynamic_cast<SPGroup *>(selection->single());
+                                if (selGroup && (selGroup->layerMode() == SPGroup::LAYER)) {
+                                    group_at_point = selGroup;
+                                }
                             }
 
                             // group-at-point is meant to be topmost item if it's a group,
@@ -673,10 +684,11 @@ bool SelectTool::root_handler(GdkEvent* event) {
                                 selection->toggle(this->item);
                             } else {
                                 SPObject* single = selection->single();
+                                SPGroup *singleGroup = dynamic_cast<SPGroup *>(single);
                                 // without shift, increase state (i.e. toggle scale/rotation handles)
                                 if (selection->includes(this->item)) {
                                     _seltrans->increaseState();
-                                } else if (SP_IS_LAYER(single) && single->isAncestorOf(this->item)) {
+                                } else if (singleGroup && (singleGroup->layerMode() == SPGroup::LAYER) && single->isAncestorOf(this->item)) {
                                     _seltrans->increaseState();
                                 } else {
                                     _seltrans->resetState();
@@ -818,7 +830,7 @@ bool SelectTool::root_handler(GdkEvent* event) {
                 SPItem *item = desktop->getItemAtPoint(p, true, NULL);
 
                 // Save pointer to current cycle-item so that we can find it again later, in the freshly built list
-                SPItem *tmp_cur_item = this->cycling_cur_item ? SP_ITEM(this->cycling_cur_item->data) : NULL;
+                SPItem *tmp_cur_item = this->cycling_cur_item ? dynamic_cast<SPItem *>(static_cast<SPObject *>(this->cycling_cur_item->data)) : NULL;
                 g_list_free(this->cycling_items);
                 this->cycling_items = NULL;
                 this->cycling_cur_item = NULL;
@@ -851,11 +863,14 @@ bool SelectTool::root_handler(GdkEvent* event) {
                     Inkscape::DrawingItem *arenaitem;
 
                     for(GList *l = this->cycling_items_cmp; l != NULL; l = l->next) {
-                        arenaitem = SP_ITEM(l->data)->get_arenaitem(desktop->dkey);
-                        arenaitem->setOpacity(1.0);
-                        //if (!shift_pressed && !g_list_find(this->cycling_items_selected_before, SP_ITEM(l->data)) && selection->includes(SP_ITEM(l->data)))
-                        if (!g_list_find(this->cycling_items_selected_before, SP_ITEM(l->data)) && selection->includes(SP_ITEM(l->data))) {
-                            selection->remove(SP_ITEM(l->data));
+                        SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(l->data));
+                        if (item) {
+                            arenaitem = item->get_arenaitem(desktop->dkey);
+                            arenaitem->setOpacity(1.0);
+                            //if (!shift_pressed && !g_list_find(this->cycling_items_selected_before, item) && selection->includes(item))
+                            if (!g_list_find(this->cycling_items_selected_before, item) && selection->includes(item)) {
+                                selection->remove(item);
+                            }
                         }
                     }
 
@@ -869,16 +884,19 @@ bool SelectTool::root_handler(GdkEvent* event) {
 
                     // ... and rebuild them with the new items.
                     this->cycling_items_cmp = g_list_copy(this->cycling_items);
-                    SPItem *item;
 
                     for(GList *l = this->cycling_items; l != NULL; l = l->next) {
-                        item = SP_ITEM(l->data);
-                        arenaitem = item->get_arenaitem(desktop->dkey);
-                        arenaitem->setOpacity(0.3);
-
-                        if (selection->includes(item)) {
-                            // already selected items are stored separately, too
-                            this->cycling_items_selected_before = g_list_append(this->cycling_items_selected_before, item);
+                        SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(l->data));
+                        if (item) {
+                            arenaitem = item->get_arenaitem(desktop->dkey);
+                            arenaitem->setOpacity(0.3);
+
+                            if (selection->includes(item)) {
+                                // already selected items are stored separately, too
+                                this->cycling_items_selected_before = g_list_append(this->cycling_items_selected_before, item);
+                            }
+                        } else {
+                            g_assert_not_reached();
                         }
                     }
 
@@ -1134,9 +1152,9 @@ bool SelectTool::root_handler(GdkEvent* event) {
                     if (MOD__CTRL_ONLY(event)) {
                         if (selection->singleItem()) {
                             SPItem *clicked_item = selection->singleItem();
-                            
-                            if ( SP_IS_GROUP(clicked_item) || SP_IS_BOX3D(clicked_item)) { // enter group or a 3D box
-                                desktop->setCurrentLayer(reinterpret_cast<SPObject *>(clicked_item));
+                            SPGroup *clickedGroup = dynamic_cast<SPGroup *>(clicked_item);
+                            if ( (clickedGroup && (clickedGroup->layerMode() == SPGroup::LAYER)) || dynamic_cast<SPBox3D *>(clicked_item)) { // enter group or a 3D box
+                                desktop->setCurrentLayer(clicked_item);
                                 sp_desktop_selection(desktop)->clear();
                             } else {
                                 this->desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Selected object is not a group. Cannot enter."));
diff --git a/src/ui/tools/spray-tool.cpp b/src/ui/tools/spray-tool.cpp
index 933da6fb1..cdc608558 100644
--- a/src/ui/tools/spray-tool.cpp
+++ b/src/ui/tools/spray-tool.cpp
@@ -384,11 +384,14 @@ static bool sp_spray_recursive(SPDesktop *desktop,
                                gint _distrib)
 {
     bool did = false;
-    
-    if (SP_IS_BOX3D(item) ) {
-        // convert 3D boxes to ordinary groups before spraying their shapes
-        item = box3d_convert_to_group(SP_BOX3D(item));
-        selection->add(item);
+
+    {
+        SPBox3D *box = dynamic_cast<SPBox3D *>(item);
+        if (box) {
+            // convert 3D boxes to ordinary groups before spraying their shapes
+            item = box3d_convert_to_group(box);
+            selection->add(item);
+        }
     }
 
     double _fid = g_random_double_range(0, 1);
@@ -413,7 +416,7 @@ static bool sp_spray_recursive(SPDesktop *desktop,
                 parent->appendChild(copy);
 
                 SPObject *new_obj = doc->getObjectByRepr(copy);
-                item_copied = SP_ITEM(new_obj);   // Convertion object->item
+                item_copied = dynamic_cast<SPItem *>(new_obj);   // Convertion object->item
                 Geom::Point center=item->getCenter();
                 sp_spray_scale_rel(center,desktop, item_copied, Geom::Scale(_scale,_scale));
                 sp_spray_scale_rel(center,desktop, item_copied, Geom::Scale(scale,scale));
@@ -437,7 +440,7 @@ static bool sp_spray_recursive(SPDesktop *desktop,
                 items != NULL;
                 items = items->next) {
 
-            SPItem *item1 = SP_ITEM(items->data);
+            SPItem *item1 = dynamic_cast<SPItem *>(static_cast<SPObject *>(items->data));
             if (i == 1) {
                 parent_item = item1;
             }
@@ -458,7 +461,7 @@ static bool sp_spray_recursive(SPDesktop *desktop,
                 Inkscape::XML::Node *copy = old_repr->duplicate(xml_doc);
                 parent->appendChild(copy);
                 SPObject *new_obj = doc->getObjectByRepr(copy);
-                item_copied = SP_ITEM(new_obj);
+                item_copied = dynamic_cast<SPItem *>(new_obj);
 
                 // Move around the cursor
                 Geom::Point move = (Geom::Point(cos(tilt)*cos(dp)*dr/(1-ratio)+sin(tilt)*sin(dp)*dr/(1+ratio), -sin(tilt)*cos(dp)*dr/(1-ratio)+cos(tilt)*sin(dp)*dr/(1+ratio)))+(p-a->midpoint()); 
@@ -503,7 +506,7 @@ static bool sp_spray_recursive(SPDesktop *desktop,
 
                 SPObject *clone_object = doc->getObjectByRepr(clone);
                 // Conversion object->item
-                item_copied = SP_ITEM(clone_object);
+                item_copied = dynamic_cast<SPItem *>(clone_object);
                 Geom::Point center = item->getCenter();
                 sp_spray_scale_rel(center, desktop, item_copied, Geom::Scale(_scale, _scale));
                 sp_spray_scale_rel(center, desktop, item_copied, Geom::Scale(scale, scale));
@@ -554,13 +557,16 @@ static bool sp_spray_dilate(SprayTool *tc, Geom::Point /*event_p*/, Geom::Point
         for (GSList *items = original_selection;
                 items != NULL;
                 items = items->next) {
-            sp_object_ref(SP_ITEM(items->data));
+            SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(items->data));
+            g_assert(item != NULL);
+            sp_object_ref(item);
         }
 
         for (GSList *items = original_selection;
                 items != NULL;
                 items = items->next) {
-            SPItem *item = SP_ITEM(items->data);
+            SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(items->data));
+            g_assert(item != NULL);
 
             if (is_transform_modes(tc->mode)) {
                 if (sp_spray_recursive(desktop, selection, item, p, vector, tc->mode, radius, move_force, tc->population, tc->scale, tc->scale_variation, reverse, move_mean, move_standard_deviation, tc->ratio, tc->tilt, tc->rotation_variation, tc->distrib)) {
@@ -576,7 +582,9 @@ static bool sp_spray_dilate(SprayTool *tc, Geom::Point /*event_p*/, Geom::Point
         for (GSList *items = original_selection;
                 items != NULL;
                 items = items->next) {
-            sp_object_unref(SP_ITEM(items->data));
+            SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(items->data));
+            g_assert(item != NULL);
+            sp_object_unref(item);
         }
     }
 
diff --git a/src/ui/tools/tweak-tool.cpp b/src/ui/tools/tweak-tool.cpp
index 340f64a0b..f56975de2 100644
--- a/src/ui/tools/tweak-tool.cpp
+++ b/src/ui/tools/tweak-tool.cpp
@@ -372,13 +372,16 @@ sp_tweak_dilate_recursive (Inkscape::Selection *selection, SPItem *item, Geom::P
 {
     bool did = false;
 
-    if (SP_IS_BOX3D(item) && !is_transform_mode(mode) && !is_color_mode(mode)) {
-        // convert 3D boxes to ordinary groups before tweaking their shapes
-        item = box3d_convert_to_group(SP_BOX3D(item));
-        selection->add(item);
+    {
+        SPBox3D *box = dynamic_cast<SPBox3D *>(item);
+        if (box && !is_transform_mode(mode) && !is_color_mode(mode)) {
+            // convert 3D boxes to ordinary groups before tweaking their shapes
+            item = box3d_convert_to_group(box);
+            selection->add(item);
+        }
     }
 
-    if (SP_IS_TEXT(item) || SP_IS_FLOWTEXT(item)) {
+    if (dynamic_cast<SPText *>(item) || dynamic_cast<SPFlowtext *>(item)) {
         GSList *items = g_slist_prepend (NULL, item);
         GSList *selected = NULL;
         GSList *to_select = NULL;
@@ -387,22 +390,25 @@ sp_tweak_dilate_recursive (Inkscape::Selection *selection, SPItem *item, Geom::P
         g_slist_free (items);
         SPObject* newObj = doc->getObjectByRepr(static_cast<Inkscape::XML::Node *>(to_select->data));
         g_slist_free (to_select);
-        item = SP_ITEM(newObj);
+        item = dynamic_cast<SPItem *>(newObj);
+        g_assert(item != NULL);
         selection->add(item);
     }
 
-    if (SP_IS_GROUP(item) && !SP_IS_BOX3D(item)) {
+    if (dynamic_cast<SPGroup *>(item) && !dynamic_cast<SPBox3D *>(item)) {
         GSList *children = NULL;
         for (SPObject *child = item->firstChild() ; child; child = child->getNext() ) {
-            if (SP_IS_ITEM(child)) {
+            if (dynamic_cast<SPItem *>(static_cast<SPObject *>(child))) {
                 children = g_slist_prepend(children, child);
             }
         }
 
         for (GSList *i = children; i; i = i->next) {
-            SPItem *child = SP_ITEM(i->data);
-            if (sp_tweak_dilate_recursive (selection, SP_ITEM(child), p, vector, mode, radius, force, fidelity, reverse))
+            SPItem *child = dynamic_cast<SPItem *>(static_cast<SPObject *>(i->data));
+            g_assert(child != NULL);
+            if (sp_tweak_dilate_recursive (selection, child, p, vector, mode, radius, force, fidelity, reverse)) {
                 did = true;
+            }
         }
 
         g_slist_free(children);
@@ -509,13 +515,13 @@ sp_tweak_dilate_recursive (Inkscape::Selection *selection, SPItem *item, Geom::P
                 }
             }
 
-        } else if (SP_IS_PATH(item) || SP_IS_SHAPE(item)) {
+        } else if (dynamic_cast<SPPath *>(item) || dynamic_cast<SPShape *>(item)) {
 
             Inkscape::XML::Node *newrepr = NULL;
             gint pos = 0;
             Inkscape::XML::Node *parent = NULL;
             char const *id = NULL;
-            if (!SP_IS_PATH(item)) {
+            if (!dynamic_cast<SPPath *>(item)) {
                 newrepr = sp_selected_item_to_curved_repr(item, 0);
                 if (!newrepr) {
                     return false;
@@ -631,7 +637,8 @@ sp_tweak_dilate_recursive (Inkscape::Selection *selection, SPItem *item, Geom::P
                     if (newrepr) {
                         newrepr->setAttribute("d", str);
                     } else {
-                        if (SP_IS_LPE_ITEM(item) && SP_LPE_ITEM(item)->hasPathEffectRecursive()) {
+                        SPLPEItem *lpeitem = dynamic_cast<SPLPEItem *>(item);
+                        if (lpeitem && lpeitem->hasPathEffectRecursive()) {
                             item->getRepr()->setAttribute("inkscape:original-d", str);
                         } else {
                             item->getRepr()->setAttribute("d", str);
@@ -769,7 +776,7 @@ static void tweak_colors_in_gradient(SPItem *item, Inkscape::PaintTarget fill_or
 {
     SPGradient *gradient = getGradient(item, fill_or_stroke);
 
-    if (!gradient || !SP_IS_GRADIENT(gradient)) {
+    if (!gradient || !dynamic_cast<SPGradient *>(gradient)) {
         return;
     }
 
@@ -780,9 +787,9 @@ static void tweak_colors_in_gradient(SPItem *item, Inkscape::PaintTarget fill_or
 
     double pos = 0;
     double r = 0;
-    if (SP_IS_LINEARGRADIENT(gradient)) {
-        SPLinearGradient *lg = SP_LINEARGRADIENT(gradient);
 
+    SPLinearGradient *lg = dynamic_cast<SPLinearGradient *>(gradient);
+    if (lg) {
         Geom::Point p1(lg->x1.computed, lg->y1.computed);
         Geom::Point p2(lg->x2.computed, lg->y2.computed);
         Geom::Point pdiff(p2 - p1);
@@ -800,11 +807,13 @@ static void tweak_colors_in_gradient(SPItem *item, Inkscape::PaintTarget fill_or
         // Calculate radius in lenfth-of-gradient-line units
         r = radius / vl;
 
-    } else if (SP_IS_RADIALGRADIENT(gradient)) {
-        SPRadialGradient *rg = SP_RADIALGRADIENT(gradient);
-        Geom::Point c (rg->cx.computed, rg->cy.computed);
-        pos = Geom::L2(p - c) / rg->r.computed;
-        r = radius / rg->r.computed;
+    } else {
+        SPRadialGradient *rg = dynamic_cast<SPRadialGradient *>(gradient);
+        if (rg) {
+            Geom::Point c (rg->cx.computed, rg->cy.computed);
+            pos = Geom::L2(p - c) / rg->r.computed;
+            r = radius / rg->r.computed;
+        }
     }
 
     // Normalize pos to 0..1, taking into accound gradient spread:
@@ -836,14 +845,16 @@ static void tweak_colors_in_gradient(SPItem *item, Inkscape::PaintTarget fill_or
     double offset_h = 0;
     SPObject *child_prev = NULL;
     for (SPObject *child = vector->firstChild(); child; child = child->getNext()) {
-        if (!SP_IS_STOP(child)) {
+        SPStop *stop = dynamic_cast<SPStop *>(child);
+        if (!stop) {
             continue;
         }
-        SPStop *stop = SP_STOP (child);
 
         offset_h = stop->offset;
 
         if (child_prev) {
+            SPStop *prevStop = dynamic_cast<SPStop *>(child_prev);
+            g_assert(prevStop != NULL);
 
             if (offset_h - offset_l > r && pos_e >= offset_l && pos_e <= offset_h) {
                 // the summit falls in this interstop, and the radius is small,
@@ -853,9 +864,9 @@ static void tweak_colors_in_gradient(SPItem *item, Inkscape::PaintTarget fill_or
                 tweak_color (mode, stop->specified_color.v.c, rgb_goal,
                                   force * (pos_e - offset_l) / (offset_h - offset_l),
                                   do_h, do_s, do_l);
-                tweak_color (mode, SP_STOP(child_prev)->specified_color.v.c, rgb_goal,
-                                  force * (offset_h - pos_e) / (offset_h - offset_l),
-                                  do_h, do_s, do_l);
+                tweak_color(mode, prevStop->specified_color.v.c, rgb_goal,
+                            force * (offset_h - pos_e) / (offset_h - offset_l),
+                            do_h, do_s, do_l);
                 stop->updateRepr();
                 child_prev->updateRepr();
                 break;
@@ -863,9 +874,9 @@ static void tweak_colors_in_gradient(SPItem *item, Inkscape::PaintTarget fill_or
                 // wide brush, may affect more than 2 stops,
                 // paint each stop by the force from the profile curve
                 if (offset_l <= pos_e && offset_l > pos_e - r) {
-                    tweak_color (mode, SP_STOP(child_prev)->specified_color.v.c, rgb_goal,
-                                 force * tweak_profile (fabs (pos_e - offset_l), r),
-                                 do_h, do_s, do_l);
+                    tweak_color(mode, prevStop->specified_color.v.c, rgb_goal,
+                                force * tweak_profile (fabs (pos_e - offset_l), r),
+                                do_h, do_s, do_l);
                     child_prev->updateRepr();
                 }
 
@@ -894,10 +905,11 @@ sp_tweak_color_recursive (guint mode, SPItem *item, SPItem *item_at_point,
 {
     bool did = false;
 
-    if (SP_IS_GROUP(item)) {
+    if (dynamic_cast<SPGroup *>(item)) {
         for (SPObject *child = item->firstChild() ; child; child = child->getNext() ) {
-            if (SP_IS_ITEM(child)) {
-                if (sp_tweak_color_recursive (mode, SP_ITEM(child), item_at_point,
+            SPItem *childItem = dynamic_cast<SPItem *>(child);
+            if (childItem) {
+                if (sp_tweak_color_recursive (mode, childItem, item_at_point,
                                           fill_goal, do_fill,
                                           stroke_goal, do_stroke,
                                           opacity_goal, do_opacity,
@@ -953,11 +965,11 @@ sp_tweak_color_recursive (guint mode, SPItem *item, SPItem *item_at_point,
                     //cycle through filter primitives
                     SPObject *primitive_obj = style->getFilter()->children;
                     while (primitive_obj) {
-                        if (SP_IS_FILTER_PRIMITIVE(primitive_obj)) {
-                            SPFilterPrimitive *primitive = SP_FILTER_PRIMITIVE(primitive_obj);
+                        SPFilterPrimitive *primitive = dynamic_cast<SPFilterPrimitive *>(primitive_obj);
+                        if (primitive) {
                             //if primitive is gaussianblur
-                            if(SP_IS_GAUSSIANBLUR(primitive)) {
-                                SPGaussianBlur * spblur = SP_GAUSSIANBLUR(primitive);
+                            SPGaussianBlur * spblur = dynamic_cast<SPGaussianBlur *>(primitive);
+                            if (spblur) {
                                 float num = spblur->stdDeviation.getNumber();
                                 blur_now += num * i2dt.descrim(); // sum all blurs in the filter
                             }
@@ -1080,7 +1092,7 @@ sp_tweak_dilate (TweakTool *tc, Geom::Point event_p, Geom::Point p, Geom::Point
          items != NULL;
          items = items->next) {
 
-        SPItem *item = SP_ITEM(items->data);
+        SPItem *item = dynamic_cast<SPItem *>(static_cast<SPObject *>(items->data));
 
         if (is_color_mode (tc->mode)) {
             if (do_fill || do_stroke || do_opacity) {