diff --git a/c++/vector/.gitignore b/c++/vector/.gitignore
index fa79505..c70101c 100644
--- a/c++/vector/.gitignore
+++ b/c++/vector/.gitignore
@@ -1,2 +1 @@
 /vector
-/*.d
diff --git a/c++/vector/activearea.cpp b/c++/vector/activearea.cpp
index 90c186f..dbbbf16 100644
--- a/c++/vector/activearea.cpp
+++ b/c++/vector/activearea.cpp
@@ -85,7 +85,7 @@ bool ActiveArea::on_motion_notify_event(GdkEventMotion* event) {
 		Vector newposition = position + drag_offset;
 		if (newposition != oldposition) {
 			drag_point->position = newposition;
-			on_point_move(drag_point, oldposition);
+			on_point_move(drag_point, oldposition, newposition);
 			queue_draw();
 		}
 	} else {
@@ -118,7 +118,7 @@ void ActiveArea::on_draw(const Context &context) {
 		context.point(**i);
 }
 
-void ActiveArea::on_point_move(const ActivePoint::Handle &/*point*/, const Vector &/*oldposition*/)
+void ActiveArea::on_point_move(const ActivePoint::Handle &/*point*/, const Vector &/*oldposition*/, const Vector &/*newposition*/)
 	{ }
 
 void ActiveArea::on_draw_content(const Context &/*context*/)
diff --git a/c++/vector/activearea.h b/c++/vector/activearea.h
index 6839412..9a32217 100644
--- a/c++/vector/activearea.h
+++ b/c++/vector/activearea.h
@@ -29,7 +29,7 @@ protected:
 
 	ActivePoint::Handle get_point_at(const Vector &position) const;
 
-	virtual void on_point_move(const ActivePoint::Handle &point, const Vector &oldposition);
+	virtual void on_point_move(const ActivePoint::Handle &point, const Vector &oldposition, const Vector &newposition);
 	virtual void on_draw(const Context &context);
 	virtual void on_draw_content(const Context &context);
 
diff --git a/c++/vector/curvesarea.cpp b/c++/vector/curvesarea.cpp
index 9672fda..10d8b56 100644
--- a/c++/vector/curvesarea.cpp
+++ b/c++/vector/curvesarea.cpp
@@ -39,7 +39,8 @@ namespace {
 }
 
 
-CurvesArea::CurvesArea()
+CurvesArea::CurvesArea():
+	w(new ActivePoint(Vector(), Color::red()))
 {
 	set_size_request(500, 500);
 	
@@ -54,6 +55,31 @@ CurvesArea::CurvesArea()
 		curve.back().add_to(*this);
 	}
 	curve.loop = true;
+	add_point(w);
+	set_width(50);
+}
+
+Real CurvesArea::get_width() const
+	{ return fabs(dot(curve.front().get_t().perp().norm(), w->position - curve.front().get_p())); }
+
+void CurvesArea::set_width(const Real &width)
+	{ w->position = curve.front().get_p() + curve.front().get_t().perp().norm()*width; }
+
+void CurvesArea::on_point_move(const ActivePoint::Handle &point, const Vector &oldposition, const Vector &newposition) {
+	Real width = -1;
+	for(Curve::const_iterator i = curve.begin(); i != curve.end(); ++i) {
+		if (i == curve.begin() && (i->p == point || i->t == point)) {
+			point->position = oldposition;
+			width = get_width();
+			point->position = newposition;
+		}
+		if (i->p == point)
+			{ i->t->position += i->p->position - oldposition; break; }
+	}
+	if (point == w)
+		width = get_width();
+	if (width >= 0)
+		set_width(width);
 }
 
 void CurvesArea::put_segment(const Context &context, const Segment &segment, const Real width) {
@@ -68,10 +94,9 @@ void CurvesArea::put_curve(const Context &context, const Curve &curve, const Rea
 	}
 }
 
-void CurvesArea::draw_curve(const Context &context, const Curve &curve) {
+void CurvesArea::draw_curve(const Context &context, const Curve &curve, const Real width) {
 	context->save();
 	
-	Real width = 50;
 	context.set_line_width_px(1);
 
 	// tangents
@@ -99,5 +124,5 @@ void CurvesArea::draw_curve(const Context &context, const Curve &curve) {
 
 
 void CurvesArea::on_draw_content(const Context &context) {
-	draw_curve(context, curve);
+	draw_curve(context, curve, get_width());
 }
diff --git a/c++/vector/curvesarea.h b/c++/vector/curvesarea.h
index 3d26d35..c233511 100644
--- a/c++/vector/curvesarea.h
+++ b/c++/vector/curvesarea.h
@@ -37,14 +37,20 @@ public:
 
 protected:
 	Curve curve;
+	ActivePoint::Handle w;
+
+	Real get_width() const;
+	void set_width(const Real &width);
 
 	void put_segment(const Context &context, const Segment &segment, const Real width = 0);
 	void put_curve(const Context &context, const Curve &curve, const Real width = 0);
-	void draw_curve(const Context &context, const Curve &curve);
+	void draw_curve(const Context &context, const Curve &curve, const Real width);
+
+	void on_point_move(const ActivePoint::Handle &point, const Vector &oldposition, const Vector &newposition) override;
+	void on_draw_content(const Context &context) override;
 	
 public:
 	CurvesArea();
-	void on_draw_content(const Context &context) override;
 };