Fix for bug 1540070

Fixed bugs:
  - https://launchpad.net/bugs/1540070

(bzr r14678)

19 files changed, 91 insertions, 190 deletions

diff --git a/src/live_effects/effect.cpp b/src/live_effects/effect.cpp
index fe7bf3a97..47fd02554 100644
--- a/src/live_effects/effect.cpp
+++ b/src/live_effects/effect.cpp
@@ -356,7 +356,8 @@ Effect::createAndApply(EffectType type, SPDocument *doc, SPItem *item)
 }
 
 Effect::Effect(LivePathEffectObject *lpeobject)
-    : _provides_knotholder_entities(false),
+    : apply_to_clippath_and_mask(false),
+      _provides_knotholder_entities(false),
       oncanvasedit_it(0),
       is_visible(_("Is visible?"), _("If unchecked, the effect remains applied to the object but is temporarily disabled on canvas"), "is_visible", &wr, this, true),
       show_orig_path(false),
diff --git a/src/live_effects/effect.h b/src/live_effects/effect.h
index ea57ff243..898e089b7 100644
--- a/src/live_effects/effect.h
+++ b/src/live_effects/effect.h
@@ -121,6 +121,7 @@ public:
     inline bool isVisible() const { return is_visible; }
 
     void editNextParamOncanvas(SPItem * item, SPDesktop * desktop);
+    bool apply_to_clippath_and_mask;
 
 protected:
     Effect(LivePathEffectObject *lpeobject);
@@ -144,6 +145,7 @@ protected:
 
     std::vector<Parameter *> param_vector;
     bool _provides_knotholder_entities;
+
     int oncanvasedit_it;
     BoolParam is_visible;
 
diff --git a/src/live_effects/lpe-bendpath.cpp b/src/live_effects/lpe-bendpath.cpp
index d7c0b69a4..bc112285f 100644
--- a/src/live_effects/lpe-bendpath.cpp
+++ b/src/live_effects/lpe-bendpath.cpp
@@ -81,6 +81,7 @@ LPEBendPath::LPEBendPath(LivePathEffectObject *lpeobject) :
     prop_scale.param_set_increments(0.01, 0.10);
 
     _provides_knotholder_entities = true;
+    apply_to_clippath_and_mask = true;
     concatenate_before_pwd2 = true;
 }
 
@@ -95,10 +96,6 @@ LPEBendPath::doBeforeEffect (SPLPEItem const* lpeitem)
     // get the item bounding box
     original_bbox(lpeitem);
     original_height = boundingbox_Y.max() - boundingbox_Y.min();
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 Geom::Piecewise<Geom::D2<Geom::SBasis> >
diff --git a/src/live_effects/lpe-copy_rotate.cpp b/src/live_effects/lpe-copy_rotate.cpp
index 87d8f05a9..8dfaf7525 100644
--- a/src/live_effects/lpe-copy_rotate.cpp
+++ b/src/live_effects/lpe-copy_rotate.cpp
@@ -61,6 +61,7 @@ LPECopyRotate::LPECopyRotate(LivePathEffectObject *lpeobject) :
 {
     show_orig_path = true;
     _provides_knotholder_entities = true;
+    apply_to_clippath_and_mask = true;
 
     // register all your parameters here, so Inkscape knows which parameters this effect has:
     registerParameter(&copiesTo360);
@@ -111,10 +112,6 @@ LPECopyRotate::doBeforeEffect (SPLPEItem const* lpeitem)
     if(copiesTo360 ){
         rot_pos = origin;
     }
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
-
 }
 
 
diff --git a/src/live_effects/lpe-envelope.cpp b/src/live_effects/lpe-envelope.cpp
index 05a672ae8..e873c0b15 100644
--- a/src/live_effects/lpe-envelope.cpp
+++ b/src/live_effects/lpe-envelope.cpp
@@ -42,6 +42,7 @@ LPEEnvelope::LPEEnvelope(LivePathEffectObject *lpeobject) :
     registerParameter( dynamic_cast<Parameter *>(&bend_path3) );
     registerParameter( dynamic_cast<Parameter *>(&bend_path4) );
     concatenate_before_pwd2 = true;
+    apply_to_clippath_and_mask = true;
 }
 
 LPEEnvelope::~LPEEnvelope()
@@ -54,9 +55,6 @@ LPEEnvelope::doBeforeEffect (SPLPEItem const* lpeitem)
 {
     // get the item bounding box
     original_bbox(lpeitem);
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 Geom::Piecewise<Geom::D2<Geom::SBasis> >
diff --git a/src/live_effects/lpe-lattice.cpp b/src/live_effects/lpe-lattice.cpp
index c05bae7e1..3c23e349e 100644
--- a/src/live_effects/lpe-lattice.cpp
+++ b/src/live_effects/lpe-lattice.cpp
@@ -78,7 +78,7 @@ LPELattice::LPELattice(LivePathEffectObject *lpeobject) :
     registerParameter( dynamic_cast<Parameter *>(&grid_point14) );
     registerParameter( dynamic_cast<Parameter *>(&grid_point15) );
 
-    
+    apply_to_clippath_and_mask = true;
 }
 
 LPELattice::~LPELattice()
@@ -176,9 +176,6 @@ void
 LPELattice::doBeforeEffect (SPLPEItem const* lpeitem)
 {
     original_bbox(lpeitem);
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 void
diff --git a/src/live_effects/lpe-lattice2.cpp b/src/live_effects/lpe-lattice2.cpp
index b749370fa..0c403daec 100644
--- a/src/live_effects/lpe-lattice2.cpp
+++ b/src/live_effects/lpe-lattice2.cpp
@@ -103,6 +103,7 @@ LPELattice2::LPELattice2(LivePathEffectObject *lpeobject) :
     registerParameter(&grid_point_28x30);
     registerParameter(&grid_point_29x31);
     registerParameter(&grid_point_32x33x34x35);
+    apply_to_clippath_and_mask = true;
 }
 
 LPELattice2::~LPELattice2()
@@ -358,9 +359,6 @@ LPELattice2::doBeforeEffect (SPLPEItem const* lpeitem)
         horizontal(grid_point_17, grid_point_19,horiz);
         horizontal(grid_point_20x21, grid_point_22x23,horiz);
     }
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 void
diff --git a/src/live_effects/lpe-mirror_symmetry.cpp b/src/live_effects/lpe-mirror_symmetry.cpp
index 783053df2..c13cffb6a 100644
--- a/src/live_effects/lpe-mirror_symmetry.cpp
+++ b/src/live_effects/lpe-mirror_symmetry.cpp
@@ -33,7 +33,7 @@ LPEMirrorSymmetry::LPEMirrorSymmetry(LivePathEffectObject *lpeobject) :
     reflection_line(_("Reflection line:"), _("Line which serves as 'mirror' for the reflection"), "reflection_line", &wr, this, "M0,0 L100,100")
 {
     show_orig_path = true;
-
+    apply_to_clippath_and_mask = true;
     registerParameter( dynamic_cast<Parameter *>(&discard_orig_path) );
     registerParameter( dynamic_cast<Parameter *>(&reflection_line) );
 }
@@ -43,14 +43,6 @@ LPEMirrorSymmetry::~LPEMirrorSymmetry()
 }
 
 void
-LPEMirrorSymmetry::doBeforeEffect (SPLPEItem const* lpeitem)
-{
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
-}
-
-void
 LPEMirrorSymmetry::doOnApply (SPLPEItem const* lpeitem)
 {
     using namespace Geom;
diff --git a/src/live_effects/lpe-mirror_symmetry.h b/src/live_effects/lpe-mirror_symmetry.h
index 7a484a473..64a72d7b3 100644
--- a/src/live_effects/lpe-mirror_symmetry.h
+++ b/src/live_effects/lpe-mirror_symmetry.h
@@ -30,8 +30,6 @@ public:
 
     virtual void doOnApply (SPLPEItem const* lpeitem);
 
-    virtual void doBeforeEffect (SPLPEItem const* lpeitem);
-
     virtual Geom::PathVector doEffect_path (Geom::PathVector const & path_in);
 
 private:
diff --git a/src/live_effects/lpe-offset.cpp b/src/live_effects/lpe-offset.cpp
index dd7af92a2..d611b88a1 100644
--- a/src/live_effects/lpe-offset.cpp
+++ b/src/live_effects/lpe-offset.cpp
@@ -31,7 +31,7 @@ LPEOffset::LPEOffset(LivePathEffectObject *lpeobject) :
     offset_pt(_("Offset"), _("Handle to control the distance of the offset from the curve"), "offset_pt", &wr, this)
 {
     show_orig_path = true;
-
+    apply_to_clippath_and_mask = true;
     registerParameter(dynamic_cast<Parameter *>(&offset_pt));
 }
 
@@ -57,14 +57,6 @@ static void append_half_circle(Geom::Piecewise<Geom::D2<Geom::SBasis> > &pwd2,
     pwd2.continuousConcat(cap_pwd2);
 }
 
-void
-LPEOffset::doBeforeEffect (SPLPEItem const* lpeitem)
-{
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
-}
-
 Geom::Piecewise<Geom::D2<Geom::SBasis> >
 LPEOffset::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in)
 {
diff --git a/src/live_effects/lpe-offset.h b/src/live_effects/lpe-offset.h
index 997311c7d..9966fd45d 100644
--- a/src/live_effects/lpe-offset.h
+++ b/src/live_effects/lpe-offset.h
@@ -28,8 +28,6 @@ public:
 
     virtual void doOnApply (SPLPEItem const* lpeitem);
 
-    virtual void doBeforeEffect (SPLPEItem const* lpeitem);
-
     virtual Geom::Piecewise<Geom::D2<Geom::SBasis> > doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in);
 
 private:
diff --git a/src/live_effects/lpe-perspective-envelope.cpp b/src/live_effects/lpe-perspective-envelope.cpp
index 72c1b0e99..5b29df4a7 100644
--- a/src/live_effects/lpe-perspective-envelope.cpp
+++ b/src/live_effects/lpe-perspective-envelope.cpp
@@ -56,6 +56,7 @@ LPEPerspectiveEnvelope::LPEPerspectiveEnvelope(LivePathEffectObject *lpeobject)
     registerParameter(&up_right_point);
     registerParameter(&down_left_point);
     registerParameter(&down_right_point);
+    apply_to_clippath_and_mask = true;
 }
 
 LPEPerspectiveEnvelope::~LPEPerspectiveEnvelope()
@@ -371,9 +372,6 @@ LPEPerspectiveEnvelope::doBeforeEffect (SPLPEItem const* lpeitem)
         horizontal(up_left_point, down_left_point,horiz);
         horizontal(up_right_point, down_right_point,horiz);
     }
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
     setDefaults();
 }
 
diff --git a/src/live_effects/lpe-perspective_path.cpp b/src/live_effects/lpe-perspective_path.cpp
index 901519b4f..c8cdd7912 100644
--- a/src/live_effects/lpe-perspective_path.cpp
+++ b/src/live_effects/lpe-perspective_path.cpp
@@ -64,6 +64,7 @@ LPEPerspectivePath::LPEPerspectivePath(LivePathEffectObject *lpeobject) :
 
     concatenate_before_pwd2 = true; // don't split the path into its subpaths
     _provides_knotholder_entities = true;
+    apply_to_clippath_and_mask = true;
 }
 
 LPEPerspectivePath::~LPEPerspectivePath()
@@ -100,8 +101,6 @@ LPEPerspectivePath::doBeforeEffect (SPLPEItem const* lpeitem)
     Geom::Affine doc2d = Geom::Scale(1, -1) * Geom::Translate(0, item->document->getHeight().value("px"));
     pmat = pmat * doc2d;
     pmat.copy_tmat(tmat);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 void LPEPerspectivePath::refresh(Gtk::Entry* perspective) {
diff --git a/src/live_effects/lpe-roughen.cpp b/src/live_effects/lpe-roughen.cpp
index b4ee54f1a..105fe2fc4 100644
--- a/src/live_effects/lpe-roughen.cpp
+++ b/src/live_effects/lpe-roughen.cpp
@@ -87,6 +87,7 @@ LPERoughen::LPERoughen(LivePathEffectObject *lpeobject)
     segments.param_set_increments(1, 1);
     segments.param_set_digits(0);
     seed = 0;
+    apply_to_clippath_and_mask = true;
 }
 
 LPERoughen::~LPERoughen() {}
@@ -102,9 +103,6 @@ void LPERoughen::doBeforeEffect(SPLPEItem const *lpeitem)
     displace_y.resetRandomizer();
     global_randomize.resetRandomizer();
     srand(1);
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 Gtk::Widget *LPERoughen::newWidget()
diff --git a/src/live_effects/lpe-simplify.cpp b/src/live_effects/lpe-simplify.cpp
index 4b62c6c65..f807bdc8d 100644
--- a/src/live_effects/lpe-simplify.cpp
+++ b/src/live_effects/lpe-simplify.cpp
@@ -60,6 +60,7 @@ LPESimplify::LPESimplify(LivePathEffectObject *lpeobject)
     helper_size.param_set_digits(2);
 
     radius_helper_nodes = 6.0;
+    apply_to_clippath_and_mask = true;
 }
 
 LPESimplify::~LPESimplify() {}
@@ -71,10 +72,7 @@ LPESimplify::doBeforeEffect (SPLPEItem const* lpeitem)
         hp.clear();
     }
     bbox = SP_ITEM(lpeitem)->visualBounds();
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
     radius_helper_nodes = helper_size;
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 Gtk::Widget *
diff --git a/src/live_effects/lpe-transform_2pts.cpp b/src/live_effects/lpe-transform_2pts.cpp
index dd1a29689..1cd59b7fa 100644
--- a/src/live_effects/lpe-transform_2pts.cpp
+++ b/src/live_effects/lpe-transform_2pts.cpp
@@ -78,6 +78,7 @@ LPETransform2Pts::LPETransform2Pts(LivePathEffectObject *lpeobject) :
     strech.param_set_range(0, 999.0);
     strech.param_set_increments(0.01, 0.01);
     strech.param_set_digits(4);
+    apply_to_clippath_and_mask = true;
 }
 
 LPETransform2Pts::~LPETransform2Pts()
@@ -167,8 +168,6 @@ LPETransform2Pts::doBeforeEffect (SPLPEItem const* lpeitem)
     previous_angle = transformed.angle();
     previous_lenght = Geom::distance((Geom::Point)start, (Geom::Point)end);
     previous_start = start;
-    splpeitem->apply_to_clippath(splpeitem);
-    splpeitem->apply_to_mask(splpeitem);
 }
 
 void
diff --git a/src/live_effects/lpe-vonkoch.cpp b/src/live_effects/lpe-vonkoch.cpp
index 7b424e019..7eda7446e 100644
--- a/src/live_effects/lpe-vonkoch.cpp
+++ b/src/live_effects/lpe-vonkoch.cpp
@@ -64,7 +64,7 @@ LPEVonKoch::LPEVonKoch(LivePathEffectObject *lpeobject) :
     registerParameter( dynamic_cast<Parameter *>(&drawall) );
     registerParameter( dynamic_cast<Parameter *>(&maxComplexity) );
     //registerParameter( dynamic_cast<Parameter *>(&draw_boxes) );
-
+    apply_to_clippath_and_mask = true;
     nbgenerations.param_make_integer();
     nbgenerations.param_set_range(0, Geom::infinity());
     maxComplexity.param_make_integer();
@@ -262,9 +262,6 @@ LPEVonKoch::doBeforeEffect (SPLPEItem const* lpeitem)
         tmp_pathv.push_back(tmp_path);
         ref_path.set_new_value(tmp_pathv,true);
     }
-    SPLPEItem * item = const_cast<SPLPEItem*>(lpeitem);
-    item->apply_to_clippath(item);
-    item->apply_to_mask(item);
 }
 
 
diff --git a/src/sp-lpe-item.cpp b/src/sp-lpe-item.cpp
index 98b77cfe8..e2afbb55b 100644
--- a/src/sp-lpe-item.cpp
+++ b/src/sp-lpe-item.cpp
@@ -209,7 +209,7 @@ Inkscape::XML::Node* SPLPEItem::write(Inkscape::XML::Document *xml_doc, Inkscape
 /**
  * returns true when LPE was successful.
  */
-bool SPLPEItem::performPathEffect(SPCurve *curve) {
+bool SPLPEItem::performPathEffect(SPCurve *curve, bool clip_paths) {
     if (!this) {
         return false;
     }
@@ -217,7 +217,7 @@ bool SPLPEItem::performPathEffect(SPCurve *curve) {
     if (!curve) {
         return false;
     }
-
+    bool apply_to_clippath_and_mask = false;
     if (this->hasPathEffect() && this->pathEffectsEnabled()) {
         for (PathEffectList::iterator it = this->path_effect_list->begin(); it != this->path_effect_list->end(); ++it)
         {
@@ -239,35 +239,42 @@ bool SPLPEItem::performPathEffect(SPCurve *curve) {
             }
 
             if (lpe->isVisible()) {
+                if(lpe->apply_to_clippath_and_mask){
+                    apply_to_clippath_and_mask = true;
+                }
                 if (lpe->acceptsNumClicks() > 0 && !lpe->isReady()) {
                     // if the effect expects mouse input before being applied and the input is not finished
                     // yet, we don't alter the path
                     return false;
                 }
+                if (clip_paths || lpe->apply_to_clippath_and_mask) {
+                    // Groups have their doBeforeEffect called elsewhere
+                    if (!SP_IS_GROUP(this)) {
+                        lpe->doBeforeEffect_impl(this);
+                    }
 
-                // Groups have their doBeforeEffect called elsewhere
-                if (!SP_IS_GROUP(this)) {
-                    lpe->doBeforeEffect_impl(this);
-                }
-
-                try {
-                    lpe->doEffect(curve);
-                }
-                catch (std::exception & e) {
-                    g_warning("Exception during LPE %s execution. \n %s", lpe->getName().c_str(), e.what());
-                    if (SP_ACTIVE_DESKTOP && SP_ACTIVE_DESKTOP->messageStack()) {
-                        SP_ACTIVE_DESKTOP->messageStack()->flash( Inkscape::WARNING_MESSAGE,
-                                        _("An exception occurred during execution of the Path Effect.") );
+                    try {
+                            lpe->doEffect(curve);
+                    }
+                    catch (std::exception & e) {
+                        g_warning("Exception during LPE %s execution. \n %s", lpe->getName().c_str(), e.what());
+                        if (SP_ACTIVE_DESKTOP && SP_ACTIVE_DESKTOP->messageStack()) {
+                            SP_ACTIVE_DESKTOP->messageStack()->flash( Inkscape::WARNING_MESSAGE,
+                                            _("An exception occurred during execution of the Path Effect.") );
+                        }
+                        return false;
+                    }
+                    if (!SP_IS_GROUP(this)) {
+                        lpe->doAfterEffect(this);
                     }
-                    return false;
-                }
-                if (!SP_IS_GROUP(this)) {
-                    lpe->doAfterEffect(this);
                 }
             }
         }
     }
-
+    if(apply_to_clippath_and_mask && clip_paths){
+        this->apply_to_clippath((SPItem *)this);
+        this->apply_to_mask((SPItem *)this);
+    }
     return true;
 }
 
@@ -641,43 +648,7 @@ SPLPEItem::apply_to_clippath(SPItem *item)
     SPClipPath *clipPath = item->clip_ref->getObject();
     if(clipPath) {
         SPObject * clip_data = clipPath->firstChild();
-        SPCurve * clip_curve = NULL;
-
-        if (SP_IS_PATH(clip_data)) {
-            clip_curve = SP_PATH(clip_data)->get_original_curve();
-        } else if(SP_IS_SHAPE(clip_data)) {
-            clip_curve = SP_SHAPE(clip_data)->getCurve();
-        } else if(SP_IS_GROUP(clip_data)) {
-            apply_to_clip_or_mask_group(SP_ITEM(clip_data), item);
-            return;
-        }
-        if(clip_curve) {
-            bool success = false;
-            if(SP_IS_GROUP(this)){
-                clip_curve->transform(i2anc_affine(SP_GROUP(item), SP_GROUP(this)));
-                success = this->performPathEffect(clip_curve);
-                clip_curve->transform(i2anc_affine(SP_GROUP(item), SP_GROUP(this)).inverse());
-            } else {
-                success = this->performPathEffect(clip_curve);
-            }
-            Inkscape::XML::Node *reprClip = clip_data->getRepr();
-            if (success) {
-                gchar *str = sp_svg_write_path(clip_curve->get_pathvector());
-                reprClip->setAttribute("d", str);
-                g_free(str);
-            } else {
-                // LPE was unsuccesfull. Read the old 'd'-attribute.
-                if (gchar const * value = reprClip->attribute("d")) {
-                    Geom::PathVector pv = sp_svg_read_pathv(value);
-                    SPCurve *oldcurve = new SPCurve(pv);
-                    if (oldcurve) {
-                        SP_SHAPE(clip_data)->setCurve(oldcurve, TRUE);
-                        oldcurve->unref();
-                    }
-                }
-            }
-            clip_curve->unref();
-        }
+        apply_to_clip_or_mask(SP_ITEM(clip_data), item);
     }
     if(SP_IS_GROUP(item)){
     	std::vector<SPItem*> item_list = sp_item_group_item_list(SP_GROUP(item));
@@ -694,42 +665,7 @@ SPLPEItem::apply_to_mask(SPItem *item)
     SPMask *mask = item->mask_ref->getObject();
     if(mask) {
         SPObject *mask_data = mask->firstChild();
-        SPCurve * mask_curve = NULL;
-        if (SP_IS_PATH(mask_data)) {
-            mask_curve = SP_PATH(mask_data)->get_original_curve();
-        } else if(SP_IS_SHAPE(mask_data)) {
-            mask_curve = SP_SHAPE(mask_data)->getCurve();
-        } else if(SP_IS_GROUP(mask_data)) {
-            apply_to_clip_or_mask_group(SP_ITEM(mask_data), item);
-            return;
-        }
-        if(mask_curve) {
-            bool success = false;
-            if(SP_IS_GROUP(this)){
-                mask_curve->transform(i2anc_affine(SP_GROUP(item), SP_GROUP(this)));
-                success = this->performPathEffect(mask_curve);
-                mask_curve->transform(i2anc_affine(SP_GROUP(item), SP_GROUP(this)).inverse());
-            } else {
-                success = this->performPathEffect(mask_curve);
-            }
-            Inkscape::XML::Node *reprmask = mask_data->getRepr();
-            if (success) {
-                gchar *str = sp_svg_write_path(mask_curve->get_pathvector());
-                reprmask->setAttribute("d", str);
-                g_free(str);
-            } else {
-                // LPE was unsuccesfull. Read the old 'd'-attribute.
-                if (gchar const * value = reprmask->attribute("d")) {
-                    Geom::PathVector pv = sp_svg_read_pathv(value);
-                    SPCurve *oldcurve = new SPCurve(pv);
-                    if (oldcurve) {
-                        SP_SHAPE(mask_data)->setCurve(oldcurve, TRUE);
-                        oldcurve->unref();
-                    }
-                }
-            }
-            mask_curve->unref();
-        }
+        apply_to_clip_or_mask(SP_ITEM(mask_data), item);
     }
     if(SP_IS_GROUP(item)){
     	std::vector<SPItem*> item_list = sp_item_group_item_list(SP_GROUP(item));
@@ -741,51 +677,57 @@ SPLPEItem::apply_to_mask(SPItem *item)
 }
 
 void
-SPLPEItem::apply_to_clip_or_mask_group(SPItem *group, SPItem *item)
+SPLPEItem::apply_to_clip_or_mask(SPItem *clip_mask, SPItem *item)
 {
-    if (!SP_IS_GROUP(group)) {
-        return;
-    }
-    std::vector<SPItem*> item_list = sp_item_group_item_list(SP_GROUP(group));
-    for ( std::vector<SPItem*>::const_iterator iter=item_list.begin();iter!=item_list.end();++iter) {
-        SPObject *subitem = *iter;
-        if (SP_IS_GROUP(subitem)) {
-            apply_to_clip_or_mask_group(SP_ITEM(subitem), item);
-        } else if (SP_IS_SHAPE(subitem)) {
-            SPCurve * c = NULL;
-
-            if (SP_IS_PATH(subitem)) {
-                c = SP_PATH(subitem)->get_original_curve();
-            } else {
-                c = SP_SHAPE(subitem)->getCurve();
-            }
-            if (c) {
-                bool success = false;
-                if(SP_IS_GROUP(group)){
+    if (SP_IS_GROUP(clip_mask)) {
+        std::vector<SPItem*> item_list = sp_item_group_item_list(SP_GROUP(clip_mask));
+        for ( std::vector<SPItem*>::const_iterator iter=item_list.begin();iter!=item_list.end();++iter) {
+            SPItem *subitem = *iter;
+            apply_to_clip_or_mask(subitem, item);
+        }
+    } else if (SP_IS_SHAPE(clip_mask)) {
+        SPCurve * c = NULL;
+
+        if (SP_IS_PATH(clip_mask)) {
+            c = SP_PATH(clip_mask)->get_original_curve();
+        } else {
+            c = SP_SHAPE(clip_mask)->getCurve();
+        }
+        if (c) {
+            bool success = false;
+            try {
+                if(SP_IS_GROUP(this)){
                     c->transform(i2anc_affine(SP_GROUP(item), SP_GROUP(this)));
-                    success = this->performPathEffect(c);
+                    success = this->performPathEffect(c, false);
                     c->transform(i2anc_affine(SP_GROUP(item), SP_GROUP(this)).inverse());
                 } else {
-                    success = this->performPathEffect(c);
+                    success = this->performPathEffect(c, false);
                 }
-                Inkscape::XML::Node *repr = subitem->getRepr();
-                if (success) {
-                    gchar *str = sp_svg_write_path(c->get_pathvector());
-                    repr->setAttribute("d", str);
-                    g_free(str);
-                } else {
-                    // LPE was unsuccesfull. Read the old 'd'-attribute.
-                    if (gchar const * value = repr->attribute("d")) {
-                        Geom::PathVector pv = sp_svg_read_pathv(value);
-                        SPCurve *oldcurve = new SPCurve(pv);
-                        if (oldcurve) {
-                            SP_SHAPE(subitem)->setCurve(oldcurve, TRUE);
-                            oldcurve->unref();
-                        }
+            } catch (std::exception & e) {
+                g_warning("Exception during LPE execution. \n %s", e.what());
+                if (SP_ACTIVE_DESKTOP && SP_ACTIVE_DESKTOP->messageStack()) {
+                    SP_ACTIVE_DESKTOP->messageStack()->flash( Inkscape::WARNING_MESSAGE,
+                                    _("An exception occurred during execution of the Path Effect.") );
+                }
+                success = false;
+            }
+            Inkscape::XML::Node *repr = clip_mask->getRepr();
+            if (success) {
+                gchar *str = sp_svg_write_path(c->get_pathvector());
+                repr->setAttribute("d", str);
+                g_free(str);
+            } else {
+                // LPE was unsuccesfull. Read the old 'd'-attribute.
+                if (gchar const * value = repr->attribute("d")) {
+                    Geom::PathVector pv = sp_svg_read_pathv(value);
+                    SPCurve *oldcurve = new SPCurve(pv);
+                    if (oldcurve) {
+                        SP_SHAPE(clip_mask)->setCurve(oldcurve, TRUE);
+                        oldcurve->unref();
                     }
                 }
-                c->unref();
             }
+            c->unref();
         }
     }
 }
diff --git a/src/sp-lpe-item.h b/src/sp-lpe-item.h
index c35ad8411..d5e868b2e 100644
--- a/src/sp-lpe-item.h
+++ b/src/sp-lpe-item.h
@@ -69,7 +69,7 @@ public:
 
     virtual void update_patheffect(bool write);
 
-    bool performPathEffect(SPCurve *curve);
+    bool performPathEffect(SPCurve *curve, bool clip_paths = true);
 
     bool pathEffectsEnabled() const;
     bool hasPathEffect() const;
@@ -93,7 +93,7 @@ public:
     void addPathEffect(LivePathEffectObject * new_lpeobj);
     void apply_to_mask(SPItem * item);
     void apply_to_clippath(SPItem * item);
-    void apply_to_clip_or_mask_group(SPItem * group, SPItem * item);
+    void apply_to_clip_or_mask(SPItem * clip_mask, SPItem * item);
     bool forkPathEffectsIfNecessary(unsigned int nr_of_allowed_users = 1);
 
     void editNextParamOncanvas(SPDesktop *dt);