Property list changes are only notified when it did change in Curve

`Object::notify_property_list_changed()` should only be called when
the structure of the property has actually changed.

The structure of the property tree has not changed if the size of the
array has not changed, and the only possibility is that the element
value has changed.

scene/resources/curve.cpp

@@ -40,11 +40,16 @@ Curve::Curve() {
 
 void Curve::set_point_count(int p_count) {
 	ERR_FAIL_COND(p_count < 0);
-	if (_points.size() >= p_count) {
+	int old_size = _points.size();
+	if (old_size == p_count) {
+		return;
+	}
+
+	if (old_size > p_count) {
 		_points.resize(p_count);
 		mark_dirty();
 	} else {
-		for (int i = p_count - _points.size(); i > 0; i--) {
+		for (int i = p_count - old_size; i > 0; i--) {
 			_add_point(Vector2());
 		}
 	}
@@ -226,6 +231,10 @@ void Curve::remove_point(int p_index) {
 }
 
 void Curve::clear_points() {
+	if (_points.is_empty()) {
+		return;
+	}
+
 	_points.clear();
 	mark_dirty();
 	notify_property_list_changed();
@@ -398,8 +407,6 @@ void Curve::set_data(const Array p_input) {
 	const unsigned int ELEMS = 5;
 	ERR_FAIL_COND(p_input.size() % ELEMS != 0);
 
-	_points.clear();
-
 	// Validate input
 	for (int i = 0; i < p_input.size(); i += ELEMS) {
 		ERR_FAIL_COND(p_input[i].get_type() != Variant::VECTOR2);
@@ -414,8 +421,11 @@ void Curve::set_data(const Array p_input) {
 		int right_mode = p_input[i + 4];
 		ERR_FAIL_COND(right_mode < 0 || right_mode >= TANGENT_MODE_COUNT);
 	}
-
-	_points.resize(p_input.size() / ELEMS);
+	int old_size = _points.size();
+	int new_size = p_input.size() / ELEMS;
+	if (old_size != new_size) {
+		_points.resize(new_size);
+	}
 
 	for (int j = 0; j < _points.size(); ++j) {
 		Point &p = _points.write[j];
@@ -431,7 +441,9 @@ void Curve::set_data(const Array p_input) {
 	}
 
 	mark_dirty();
-	notify_property_list_changed();
+	if (old_size != new_size) {
+		notify_property_list_changed();
+	}
 }
 
 void Curve::bake() {
@@ -636,11 +648,16 @@ int Curve2D::get_point_count() const {
 
 void Curve2D::set_point_count(int p_count) {
 	ERR_FAIL_COND(p_count < 0);
-	if (points.size() >= p_count) {
+	int old_size = points.size();
+	if (old_size == p_count) {
+		return;
+	}
+
+	if (old_size > p_count) {
 		points.resize(p_count);
 		mark_dirty();
 	} else {
-		for (int i = p_count - points.size(); i > 0; i--) {
+		for (int i = p_count - old_size; i > 0; i--) {
 			_add_point(Vector2());
 		}
 	}
@@ -1128,7 +1145,11 @@ void Curve2D::_set_data(const Dictionary &p_data) {
 	PackedVector2Array rp = p_data["points"];
 	int pc = rp.size();
 	ERR_FAIL_COND(pc % 3 != 0);
-	points.resize(pc / 3);
+	int old_size = points.size();
+	int new_size = pc / 3;
+	if (old_size != new_size) {
+		points.resize(new_size);
+	}
 	const Vector2 *r = rp.ptr();
 
 	for (int i = 0; i < points.size(); i++) {
@@ -1138,7 +1159,9 @@ void Curve2D::_set_data(const Dictionary &p_data) {
 	}
 
 	mark_dirty();
-	notify_property_list_changed();
+	if (old_size != new_size) {
+		notify_property_list_changed();
+	}
 }
 
 PackedVector2Array Curve2D::tessellate(int p_max_stages, real_t p_tolerance) const {
@@ -1330,11 +1353,16 @@ int Curve3D::get_point_count() const {
 
 void Curve3D::set_point_count(int p_count) {
 	ERR_FAIL_COND(p_count < 0);
-	if (points.size() >= p_count) {
+	int old_size = points.size();
+	if (old_size == p_count) {
+		return;
+	}
+
+	if (old_size > p_count) {
 		points.resize(p_count);
 		mark_dirty();
 	} else {
-		for (int i = p_count - points.size(); i > 0; i--) {
+		for (int i = p_count - old_size; i > 0; i--) {
 			_add_point(Vector3());
 		}
 	}
@@ -2036,7 +2064,11 @@ void Curve3D::_set_data(const Dictionary &p_data) {
 	PackedVector3Array rp = p_data["points"];
 	int pc = rp.size();
 	ERR_FAIL_COND(pc % 3 != 0);
-	points.resize(pc / 3);
+	int old_size = points.size();
+	int new_size = pc / 3;
+	if (old_size != new_size) {
+		points.resize(new_size);
+	}
 	const Vector3 *r = rp.ptr();
 	Vector<real_t> rtl = p_data["tilts"];
 	const real_t *rt = rtl.ptr();
@@ -2049,7 +2081,9 @@ void Curve3D::_set_data(const Dictionary &p_data) {
 	}
 
 	mark_dirty();
-	notify_property_list_changed();
+	if (old_size != new_size) {
+		notify_property_list_changed();
+	}
 }
 
 PackedVector3Array Curve3D::tessellate(int p_max_stages, real_t p_tolerance) const {