Run clang-tidy’s modernize-use-nullptr pass.

This replaces all NULL or 0 with nullptr when assigned to or returned as
a pointer.

26 files changed, 57 insertions, 57 deletions

diff --git a/src/live_effects/parameter/array.cpp b/src/live_effects/parameter/array.cpp
index 7470f54cd..3c1498fc3 100644
--- a/src/live_effects/parameter/array.cpp
+++ b/src/live_effects/parameter/array.cpp
@@ -57,7 +57,7 @@ ArrayParam<std::vector<Satellite > >::readsvg(const gchar * str)
     }
     gchar ** strarray = g_strsplit(str, "@", 0);
     gchar ** iter = strarray;
-    while (*iter != NULL) {
+    while (*iter != nullptr) {
         gchar ** strsubarray = g_strsplit(*iter, ",", 8);
         if (*strsubarray[7]) {//steps always > 0
             Satellite *satellite = new Satellite();
diff --git a/src/live_effects/parameter/array.h b/src/live_effects/parameter/array.h
index be19889b3..156de2f81 100644
--- a/src/live_effects/parameter/array.h
+++ b/src/live_effects/parameter/array.h
@@ -46,14 +46,14 @@ public:
     }
 
     Gtk::Widget * param_newWidget() override {
-        return NULL;
+        return nullptr;
     }
 
     bool param_readSVGValue(const gchar * strvalue) override {
         _vector.clear();
         gchar ** strarray = g_strsplit(strvalue, "|", 0);
         gchar ** iter = strarray;
-        while (*iter != NULL) {
+        while (*iter != nullptr) {
             _vector.push_back( readsvg(*iter) );
             iter++;
         }
diff --git a/src/live_effects/parameter/bool.cpp b/src/live_effects/parameter/bool.cpp
index bfbda2bfd..2e8c4dbcc 100644
--- a/src/live_effects/parameter/bool.cpp
+++ b/src/live_effects/parameter/bool.cpp
@@ -84,7 +84,7 @@ BoolParam::param_newWidget()
         checkwdg->set_undo_parameters(SP_VERB_DIALOG_LIVE_PATH_EFFECT, _("Change bool parameter"));
         return dynamic_cast<Gtk::Widget *> (checkwdg);
     } else {
-        return NULL;
+        return nullptr;
     }
 }
 
diff --git a/src/live_effects/parameter/colorpicker.cpp b/src/live_effects/parameter/colorpicker.cpp
index d4ebdaa1c..ec2b18389 100644
--- a/src/live_effects/parameter/colorpicker.cpp
+++ b/src/live_effects/parameter/colorpicker.cpp
@@ -43,7 +43,7 @@ ColorPickerParam::param_set_default()
 static guint32 sp_read_color_alpha(gchar const *str, guint32 def)
 {
     guint32 val = 0;
-    if (str == NULL) return def;
+    if (str == nullptr) return def;
     while ((*str <= ' ') && *str) str++;
     if (!*str) return def;
 
diff --git a/src/live_effects/parameter/hidden.cpp b/src/live_effects/parameter/hidden.cpp
index 5a21f572b..fd062d277 100644
--- a/src/live_effects/parameter/hidden.cpp
+++ b/src/live_effects/parameter/hidden.cpp
@@ -69,7 +69,7 @@ HiddenParam::param_getDefaultSVGValue() const
 Gtk::Widget *
 HiddenParam::param_newWidget()
 {
-    return NULL;
+    return nullptr;
 }
 
 void
diff --git a/src/live_effects/parameter/item.cpp b/src/live_effects/parameter/item.cpp
index 2107a5912..c22a3df33 100644
--- a/src/live_effects/parameter/item.cpp
+++ b/src/live_effects/parameter/item.cpp
@@ -40,7 +40,7 @@ ItemParam::ItemParam( const Glib::ustring& label, const Glib::ustring& tip,
                       Effect* effect, const gchar * default_value)
     : Parameter(label, tip, key, wr, effect),
       changed(true),
-      href(NULL),
+      href(nullptr),
       ref( (SPObject*)effect->getLPEObj() )
 {
     last_transform = Geom::identity();
@@ -154,7 +154,7 @@ ItemParam::addCanvasIndicators(SPLPEItem const*/*lpeitem*/, std::vector<Geom::Pa
 void
 ItemParam::start_listening(SPObject * to)
 {
-    if ( to == NULL ) {
+    if ( to == nullptr ) {
         return;
     }
     linked_delete_connection = to->connectDelete(sigc::mem_fun(*this, &ItemParam::linked_delete));
@@ -188,7 +188,7 @@ ItemParam::remove_link()
     if (href) {
         ref.detach();
         g_free(href);
-        href = NULL;
+        href = nullptr;
     }
 }
 
diff --git a/src/live_effects/parameter/message.cpp b/src/live_effects/parameter/message.cpp
index 03eb2219f..a6e919558 100644
--- a/src/live_effects/parameter/message.cpp
+++ b/src/live_effects/parameter/message.cpp
@@ -20,7 +20,7 @@ MessageParam::MessageParam( const Glib::ustring& label, const Glib::ustring& tip
       message(default_message),
       defmessage(default_message)
 {
-    _label  = NULL;
+    _label  = nullptr;
     _min_height = -1;
 }
 
diff --git a/src/live_effects/parameter/originalitem.cpp b/src/live_effects/parameter/originalitem.cpp
index 52e4c2fd8..820c4d6b9 100644
--- a/src/live_effects/parameter/originalitem.cpp
+++ b/src/live_effects/parameter/originalitem.cpp
@@ -105,7 +105,7 @@ OriginalItemParam::on_select_original_button_click()
 {
     SPDesktop *desktop = SP_ACTIVE_DESKTOP;
     SPItem *original = ref.getObject();
-    if (desktop == NULL || original == NULL) {
+    if (desktop == nullptr || original == nullptr) {
         return;
     }
     Inkscape::Selection *selection = desktop->getSelection();
diff --git a/src/live_effects/parameter/originalitem.h b/src/live_effects/parameter/originalitem.h
index 4b285f8e1..d070161ac 100644
--- a/src/live_effects/parameter/originalitem.h
+++ b/src/live_effects/parameter/originalitem.h
@@ -23,7 +23,7 @@ public:
                 Inkscape::UI::Widget::Registry* wr,
                 Effect* effect);
     ~OriginalItemParam() override;
-    bool linksToItem() const { return (href != NULL); }
+    bool linksToItem() const { return (href != nullptr); }
     SPItem * getObject() const { return ref.getObject(); }
 
     Gtk::Widget * param_newWidget() override;
diff --git a/src/live_effects/parameter/originalitemarray.cpp b/src/live_effects/parameter/originalitemarray.cpp
index 5a0d67d26..3116b1f9c 100644
--- a/src/live_effects/parameter/originalitemarray.cpp
+++ b/src/live_effects/parameter/originalitemarray.cpp
@@ -323,7 +323,7 @@ void OriginalItemArrayParam::unlink(ItemAndActive* to)
     to->ref.detach();
     if (to->href) {
         g_free(to->href);
-        to->href = NULL;
+        to->href = nullptr;
     }    
 }
 
@@ -398,12 +398,12 @@ bool OriginalItemArrayParam::param_readSVGValue(const gchar* strvalue)
         _store->clear();
 
         gchar ** strarray = g_strsplit(strvalue, "|", 0);
-        for (gchar ** iter = strarray; *iter != NULL; iter++) {
+        for (gchar ** iter = strarray; *iter != nullptr; iter++) {
             if ((*iter)[0] == '#') {
                 gchar ** substrarray = g_strsplit(*iter, ",", 0);
                 ItemAndActive* w = new ItemAndActive((SPObject *)param_effect->getLPEObj());
                 w->href = g_strdup(*substrarray);
-                w->actived = *(substrarray+1) != NULL && (*(substrarray+1))[0] == '1';
+                w->actived = *(substrarray+1) != nullptr && (*(substrarray+1))[0] == '1';
                 w->linked_changed_connection = w->ref.changedSignal().connect(sigc::bind<ItemAndActive *>(sigc::mem_fun(*this, &OriginalItemArrayParam::linked_changed), w));
                 w->ref.attach(URI(w->href));
 
diff --git a/src/live_effects/parameter/originalitemarray.h b/src/live_effects/parameter/originalitemarray.h
index edb5a3be5..968aeaff0 100644
--- a/src/live_effects/parameter/originalitemarray.h
+++ b/src/live_effects/parameter/originalitemarray.h
@@ -32,7 +32,7 @@ namespace LivePathEffect {
 class ItemAndActive {
 public:
     ItemAndActive(SPObject *owner)
-    : href(NULL),
+    : href(nullptr),
     ref(owner),
     actived(true)
     {
diff --git a/src/live_effects/parameter/originalpath.cpp b/src/live_effects/parameter/originalpath.cpp
index 018e1e69e..5ad5546da 100644
--- a/src/live_effects/parameter/originalpath.cpp
+++ b/src/live_effects/parameter/originalpath.cpp
@@ -90,7 +90,7 @@ OriginalPathParam::param_newWidget()
 void
 OriginalPathParam::linked_modified_callback(SPObject *linked_obj, guint /*flags*/)
 {
-    SPCurve *curve = NULL;
+    SPCurve *curve = nullptr;
     if (SP_IS_SHAPE(linked_obj)) {
         if (_from_original_d) {
             curve = SP_SHAPE(linked_obj)->getCurveForEdit();
@@ -102,7 +102,7 @@ OriginalPathParam::linked_modified_callback(SPObject *linked_obj, guint /*flags*
         curve = SP_TEXT(linked_obj)->getNormalizedBpath();
     }
 
-    if (curve == NULL) {
+    if (curve == nullptr) {
         // curve invalid, set empty pathvector
         _pathvector = Geom::PathVector();
     } else {
@@ -128,7 +128,7 @@ OriginalPathParam::on_select_original_button_click()
 {
     SPDesktop *desktop = SP_ACTIVE_DESKTOP;
     SPItem *original = ref.getObject();
-    if (desktop == NULL || original == NULL) {
+    if (desktop == nullptr || original == nullptr) {
         return;
     }
     Inkscape::Selection *selection = desktop->getSelection();
diff --git a/src/live_effects/parameter/originalpath.h b/src/live_effects/parameter/originalpath.h
index bd7b10741..4432d063d 100644
--- a/src/live_effects/parameter/originalpath.h
+++ b/src/live_effects/parameter/originalpath.h
@@ -24,7 +24,7 @@ public:
                 Effect* effect);
     ~OriginalPathParam() override;
 
-    bool linksToPath() const { return (href != NULL); }
+    bool linksToPath() const { return (href != nullptr); }
     SPItem * getObject() const { return ref.getObject(); }
 
     Gtk::Widget * param_newWidget() override;
diff --git a/src/live_effects/parameter/originalpatharray.cpp b/src/live_effects/parameter/originalpatharray.cpp
index 2091c4d71..f9e56c8f3 100644
--- a/src/live_effects/parameter/originalpatharray.cpp
+++ b/src/live_effects/parameter/originalpatharray.cpp
@@ -363,7 +363,7 @@ void OriginalPathArrayParam::unlink(PathAndDirectionAndVisible* to)
     to->_pathvector = Geom::PathVector();
     if (to->href) {
         g_free(to->href);
-        to->href = NULL;
+        to->href = nullptr;
     }
 }
 
@@ -424,7 +424,7 @@ void OriginalPathArrayParam::setPathVector(SPObject *linked_obj, guint /*flags*/
     if (!to) {
         return;
     }
-    SPCurve *curve = NULL;
+    SPCurve *curve = nullptr;
     if (SP_IS_SHAPE(linked_obj)) {
         SPLPEItem * lpe_item = SP_LPE_ITEM(linked_obj);
         if (_from_original_d) {
@@ -451,7 +451,7 @@ void OriginalPathArrayParam::setPathVector(SPObject *linked_obj, guint /*flags*/
         curve = SP_TEXT(linked_obj)->getNormalizedBpath();
     }
 
-    if (curve == NULL) {
+    if (curve == nullptr) {
         // curve invalid, set empty pathvector
         to->_pathvector = Geom::PathVector();
     } else {
@@ -483,14 +483,14 @@ bool OriginalPathArrayParam::param_readSVGValue(const gchar* strvalue)
         _store->clear();
 
         gchar ** strarray = g_strsplit(strvalue, "|", 0);
-        for (gchar ** iter = strarray; *iter != NULL; iter++) {
+        for (gchar ** iter = strarray; *iter != nullptr; iter++) {
             if ((*iter)[0] == '#') {
                 gchar ** substrarray = g_strsplit(*iter, ",", 0);
                 PathAndDirectionAndVisible* w = new PathAndDirectionAndVisible((SPObject *)param_effect->getLPEObj());
                 w->href = g_strdup(*substrarray);
-                w->reversed = *(substrarray+1) != NULL && (*(substrarray+1))[0] == '1';
+                w->reversed = *(substrarray+1) != nullptr && (*(substrarray+1))[0] == '1';
                 //Like this to make backwards compatible, new value added in 0.93
-                w->visibled = *(substrarray+2) == NULL || (*(substrarray+2))[0] == '1';
+                w->visibled = *(substrarray+2) == nullptr || (*(substrarray+2))[0] == '1';
                 w->linked_changed_connection = w->ref.changedSignal().connect(sigc::bind<PathAndDirectionAndVisible *>(sigc::mem_fun(*this, &OriginalPathArrayParam::linked_changed), w));
                 w->ref.attach(URI(w->href));
 
diff --git a/src/live_effects/parameter/originalpatharray.h b/src/live_effects/parameter/originalpatharray.h
index 92edff103..23a41215f 100644
--- a/src/live_effects/parameter/originalpatharray.h
+++ b/src/live_effects/parameter/originalpatharray.h
@@ -32,7 +32,7 @@ namespace LivePathEffect {
 class PathAndDirectionAndVisible {
 public:
     PathAndDirectionAndVisible(SPObject *owner)
-    : href(NULL),
+    : href(nullptr),
     ref(owner),
     _pathvector(Geom::PathVector()),
     reversed(false),
diff --git a/src/live_effects/parameter/parameter.cpp b/src/live_effects/parameter/parameter.cpp
index a175359f0..acfe159ab 100644
--- a/src/live_effects/parameter/parameter.cpp
+++ b/src/live_effects/parameter/parameter.cpp
@@ -196,7 +196,7 @@ ScalarParam::param_newWidget()
         }
         return dynamic_cast<Gtk::Widget *> (rsu);
     } else {
-        return NULL;
+        return nullptr;
     }
 }
 
diff --git a/src/live_effects/parameter/path.cpp b/src/live_effects/parameter/path.cpp
index ab385daa6..649d3a1ef 100644
--- a/src/live_effects/parameter/path.cpp
+++ b/src/live_effects/parameter/path.cpp
@@ -64,7 +64,7 @@ PathParam::PathParam( const Glib::ustring& label, const Glib::ustring& tip,
       _pathvector(),
       _pwd2(),
       must_recalculate_pwd2(false),
-      href(NULL),
+      href(nullptr),
       ref( (SPObject*)effect->getLPEObj() )
 {
     defvalue = g_strdup(default_value);
@@ -198,8 +198,8 @@ PathParam::param_newWidget()
     Gtk::Label* pLabel = Gtk::manage(new Gtk::Label(param_label));
     static_cast<Gtk::HBox*>(_widget)->pack_start(*pLabel, true, true);
     pLabel->set_tooltip_text(param_tooltip);
-    Gtk::Image * pIcon = NULL;
-    Gtk::Button * pButton = NULL;
+    Gtk::Image * pIcon = nullptr;
+    Gtk::Button * pButton = nullptr;
     if (_edit_button) {
         pIcon = Gtk::manage(new Gtk::Image());
         pIcon->set_from_icon_name( INKSCAPE_ICON("tool-node-editor"), Gtk::ICON_SIZE_BUTTON);
@@ -398,7 +398,7 @@ PathParam::emit_changed()
 void
 PathParam::start_listening(SPObject * to)
 {
-    if ( to == NULL ) {
+    if ( to == nullptr ) {
         return;
     }
     linked_delete_connection = to->connectDelete(sigc::mem_fun(*this, &PathParam::linked_delete));
@@ -432,7 +432,7 @@ PathParam::remove_link()
     if (href) {
         ref.detach();
         g_free(href);
-        href = NULL;
+        href = nullptr;
     }
 }
 
@@ -457,7 +457,7 @@ void PathParam::linked_transformed(Geom::Affine const *rel_transf, SPItem *moved
 void
 PathParam::linked_modified_callback(SPObject *linked_obj, guint /*flags*/)
 {
-    SPCurve *curve = NULL;
+    SPCurve *curve = nullptr;
     if (SP_IS_SHAPE(linked_obj)) {
         if (_from_original_d) {
             curve = SP_SHAPE(linked_obj)->getCurveForEdit();
@@ -469,7 +469,7 @@ PathParam::linked_modified_callback(SPObject *linked_obj, guint /*flags*/)
         curve = SP_TEXT(linked_obj)->getNormalizedBpath();
     }
 
-    if (curve == NULL) {
+    if (curve == nullptr) {
         // curve invalid, set default value
         _pathvector = sp_svg_read_pathv(defvalue);
     } else {
@@ -492,7 +492,7 @@ void
 PathParam::on_edit_button_click()
 {
     SPItem * item = SP_ACTIVE_DESKTOP->getSelection()->singleItem();
-    if (item != NULL) {
+    if (item != nullptr) {
         param_editOncanvas(item, SP_ACTIVE_DESKTOP);
     }
 }
@@ -505,7 +505,7 @@ PathParam::paste_param_path(const char *svgd)
         // remove possible link to path
         remove_link();
         SPItem * item = SP_ACTIVE_DESKTOP->getSelection()->singleItem();
-        if (item != NULL) {
+        if (item != nullptr) {
             Geom::PathVector path_clipboard =  sp_svg_read_pathv(svgd);
             path_clipboard *= item->i2doc_affine().inverse();
             svgd = sp_svg_write_path( path_clipboard );
diff --git a/src/live_effects/parameter/point.cpp b/src/live_effects/parameter/point.cpp
index fe0699a19..a195d663b 100644
--- a/src/live_effects/parameter/point.cpp
+++ b/src/live_effects/parameter/point.cpp
@@ -25,7 +25,7 @@ PointParam::PointParam( const Glib::ustring& label, const Glib::ustring& tip,
     :   Parameter(label, tip, key, wr, effect), 
         defvalue(default_value),
         liveupdate(live_update),
-        _knot_entity(NULL)
+        _knot_entity(nullptr)
 {
     knot_shape = SP_KNOT_SHAPE_DIAMOND;
     knot_mode  = SP_KNOT_MODE_XOR;
@@ -185,7 +185,7 @@ PointParam::set_oncanvas_looks(SPKnotShapeType shape, SPKnotModeType mode, guint
 class PointParamKnotHolderEntity : public KnotHolderEntity {
 public:
     PointParamKnotHolderEntity(PointParam *p) { this->pparam = p; }
-    ~PointParamKnotHolderEntity() override { this->pparam->_knot_entity = NULL;}
+    ~PointParamKnotHolderEntity() override { this->pparam->_knot_entity = nullptr;}
 
     void knot_set(Geom::Point const &p, Geom::Point const &origin, guint state) override;
     Geom::Point knot_get() const override;
@@ -239,7 +239,7 @@ PointParam::addKnotHolderEntities(KnotHolder *knotholder, SPItem *item)
 {
     _knot_entity = new PointParamKnotHolderEntity(this);
     // TODO: can we ditch handleTip() etc. because we have access to handle_tip etc. itself???
-    _knot_entity->create(NULL, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, handleTip(), knot_shape, knot_mode, knot_color);
+    _knot_entity->create(nullptr, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, handleTip(), knot_shape, knot_mode, knot_color);
     knotholder->add(_knot_entity);
 }
 
diff --git a/src/live_effects/parameter/point.h b/src/live_effects/parameter/point.h
index 4f93b5354..7c620f502 100644
--- a/src/live_effects/parameter/point.h
+++ b/src/live_effects/parameter/point.h
@@ -29,7 +29,7 @@ public:
                 const Glib::ustring& key,
                 Inkscape::UI::Widget::Registry* wr,
                 Effect* effect,
-                const gchar *handle_tip = NULL,// tip for automatically associated on-canvas handle
+                const gchar *handle_tip = nullptr,// tip for automatically associated on-canvas handle
                 Geom::Point default_value = Geom::Point(0,0), 
                 bool live_update = true );
     ~PointParam() override;
diff --git a/src/live_effects/parameter/powerstrokepointarray.cpp b/src/live_effects/parameter/powerstrokepointarray.cpp
index cf4adc5fd..0857deab5 100644
--- a/src/live_effects/parameter/powerstrokepointarray.cpp
+++ b/src/live_effects/parameter/powerstrokepointarray.cpp
@@ -39,7 +39,7 @@ PowerStrokePointArrayParam::~PowerStrokePointArrayParam()
 Gtk::Widget *
 PowerStrokePointArrayParam::param_newWidget()
 {
-    return NULL;
+    return nullptr;
 }
 
 void PowerStrokePointArrayParam::param_transform_multiply(Geom::Affine const &postmul, bool /*set*/)
@@ -280,7 +280,7 @@ void PowerStrokePointArrayParam::addKnotHolderEntities(KnotHolder *knotholder, S
 {
     for (unsigned int i = 0; i < _vector.size(); ++i) {
         PowerStrokePointArrayParamKnotHolderEntity *e = new PowerStrokePointArrayParamKnotHolderEntity(this, i);
-        e->create(NULL, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN,
+        e->create(nullptr, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN,
                    _("<b>Stroke width control point</b>: drag to alter the stroke width. <b>Ctrl+click</b> adds a control point, <b>Ctrl+Alt+click</b> deletes it, <b>Shift+click</b> launches width dialog."),
                    knot_shape, knot_mode, knot_color);
         knotholder->add(e);
diff --git a/src/live_effects/parameter/satellitesarray.cpp b/src/live_effects/parameter/satellitesarray.cpp
index c6f5492d1..10ad0df45 100644
--- a/src/live_effects/parameter/satellitesarray.cpp
+++ b/src/live_effects/parameter/satellitesarray.cpp
@@ -26,7 +26,7 @@ SatellitesArrayParam::SatellitesArrayParam(const Glib::ustring &label,
         const Glib::ustring &key,
         Inkscape::UI::Widget::Registry *wr,
         Effect *effect)
-    : ArrayParam<std::vector<Satellite> >(label, tip, key, wr, effect, 0), _knoth(NULL)
+    : ArrayParam<std::vector<Satellite> >(label, tip, key, wr, effect, 0), _knoth(nullptr)
 {
     _knot_shape = SP_KNOT_SHAPE_DIAMOND;
     _knot_mode = SP_KNOT_MODE_XOR;
@@ -36,7 +36,7 @@ SatellitesArrayParam::SatellitesArrayParam(const Glib::ustring &label,
     _global_knot_hide = false;
     _current_zoom = 0;
     _effectType = FILLET_CHAMFER;
-    _last_pathvector_satellites = NULL;
+    _last_pathvector_satellites = nullptr;
     param_widget_is_visible(false);
 }
 
@@ -269,7 +269,7 @@ void SatellitesArrayParam::addKnotHolderEntities(KnotHolder *knotholder,
                             "<b>Ctrl+Alt+Click</b> reset");
                 }
                 FilletChamferKnotHolderEntity *e = new FilletChamferKnotHolderEntity(this, index);
-                e->create(NULL, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, _(tip),_knot_shape, _knot_mode, _knot_color);
+                e->create(nullptr, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, _(tip),_knot_shape, _knot_mode, _knot_color);
                 knotholder->add(e);
             }
             index++;
diff --git a/src/live_effects/parameter/satellitesarray.h b/src/live_effects/parameter/satellitesarray.h
index 30e196e41..005ea63ff 100644
--- a/src/live_effects/parameter/satellitesarray.h
+++ b/src/live_effects/parameter/satellitesarray.h
@@ -38,7 +38,7 @@ public:
 
     Gtk::Widget *param_newWidget() override
     {
-        return NULL;
+        return nullptr;
     }
     virtual void setHelperSize(int hs);
     void addKnotHolderEntities(KnotHolder *knotholder, SPItem *item) override;
@@ -87,7 +87,7 @@ public:
     FilletChamferKnotHolderEntity(SatellitesArrayParam *p, size_t index);
     ~FilletChamferKnotHolderEntity() override
     {
-        _pparam->_knoth = NULL;
+        _pparam->_knoth = nullptr;
     }
 
     void knot_set(Geom::Point const &p, Geom::Point const &origin,
diff --git a/src/live_effects/parameter/text.h b/src/live_effects/parameter/text.h
index cd1176bc2..fda470638 100644
--- a/src/live_effects/parameter/text.h
+++ b/src/live_effects/parameter/text.h
@@ -73,9 +73,9 @@ private:
 class TextParamInternal : public TextParam {
 public:
     TextParamInternal(Effect* effect) :
-        TextParam("", "", "", NULL, effect) {}
+        TextParam("", "", "", nullptr, effect) {}
 
-    Gtk::Widget * param_newWidget() override { return NULL; }
+    Gtk::Widget * param_newWidget() override { return nullptr; }
 };
 
 } //namespace LivePathEffect
diff --git a/src/live_effects/parameter/togglebutton.cpp b/src/live_effects/parameter/togglebutton.cpp
index bb9d9a90e..b5f7f5998 100644
--- a/src/live_effects/parameter/togglebutton.cpp
+++ b/src/live_effects/parameter/togglebutton.cpp
@@ -29,7 +29,7 @@ ToggleButtonParam::ToggleButtonParam( const Glib::ustring& label, const Glib::us
     : Parameter(label, tip, key, wr, effect), value(default_value), defvalue(default_value),
       inactive_label(inactive_label), _icon_active(_icon_active), _icon_inactive(_icon_inactive), _icon_size(_icon_size)
 {
-    checkwdg = NULL;
+    checkwdg = nullptr;
 }
 
 ToggleButtonParam::~ToggleButtonParam()
@@ -107,7 +107,7 @@ ToggleButtonParam::param_newWidget()
             _icon_inactive = _icon_active;
         }
         gtk_widget_show(box_button);
-        GtkWidget *icon_button = NULL;
+        GtkWidget *icon_button = nullptr;
         if(!value){ 
             icon_button = gtk_image_new_from_icon_name(_icon_inactive, _icon_size);
         } else {
@@ -156,7 +156,7 @@ ToggleButtonParam::refresh_button()
         }
     }
     if ( _icon_active ) {
-        GdkPixbuf * icon_pixbuf = NULL;
+        GdkPixbuf * icon_pixbuf = nullptr;
         Gtk::Image *im = dynamic_cast<Gtk::Image*>(children[0]);
         Gtk::IconSize is(_icon_size);
         if (!im) return;
diff --git a/src/live_effects/parameter/togglebutton.h b/src/live_effects/parameter/togglebutton.h
index 7476698f5..29ee72203 100644
--- a/src/live_effects/parameter/togglebutton.h
+++ b/src/live_effects/parameter/togglebutton.h
@@ -31,8 +31,8 @@ public:
                Effect* effect,
                bool default_value = false,
                const Glib::ustring& inactive_label = "",
-               char const * icon_active = NULL,
-               char const * icon_inactive = NULL,
+               char const * icon_active = nullptr,
+               char const * icon_inactive = nullptr,
                GtkIconSize icon_size = GTK_ICON_SIZE_SMALL_TOOLBAR);
     ~ToggleButtonParam() override;
 
diff --git a/src/live_effects/parameter/vector.cpp b/src/live_effects/parameter/vector.cpp
index 56895276c..8018ed618 100644
--- a/src/live_effects/parameter/vector.cpp
+++ b/src/live_effects/parameter/vector.cpp
@@ -216,11 +216,11 @@ void
 VectorParam::addKnotHolderEntities(KnotHolder *knotholder, SPItem *item)
 {
     VectorParamKnotHolderEntity_Origin *origin_e = new VectorParamKnotHolderEntity_Origin(this);
-    origin_e->create(NULL, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, handleTip(), ori_knot_shape, ori_knot_mode, ori_knot_color);
+    origin_e->create(nullptr, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, handleTip(), ori_knot_shape, ori_knot_mode, ori_knot_color);
     knotholder->add(origin_e);
 
     VectorParamKnotHolderEntity_Vector *vector_e = new VectorParamKnotHolderEntity_Vector(this);
-    vector_e->create(NULL, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, handleTip(), vec_knot_shape, vec_knot_mode, vec_knot_color);
+    vector_e->create(nullptr, item, knotholder, Inkscape::CTRL_TYPE_UNKNOWN, handleTip(), vec_knot_shape, vec_knot_mode, vec_knot_color);
     knotholder->add(vector_e);
 }