docs: public ReadOnlyDoubleProperty lengthSquaredProperty() {
  		if (this.lengthSquareProperty == null) {
  			this.lengthSquareProperty = new ReadOnlyDoubleWrapper(this, MathFXAttributeNames.LENGTH_SQUARED);
  			this.lengthSquareProperty.bind(Bindings.createDoubleBinding(() ->
  				Vector2dfx.this.x.doubleValue() * Vector2dfx.this.x.doubleValue()
  						+ Vector2dfx.this.y.doubleValue() * Vector2dfx.this.y.doubleValue(), this.x, this.y));
  		}
  		return this.lengthSquareProperty.getReadOnlyProperty();
  	}