diff --git a/charming/src/element/label.rs b/charming/src/element/label.rs
index 240aed6..dd0662e 100644
--- a/charming/src/element/label.rs
+++ b/charming/src/element/label.rs
@@ -1,6 +1,6 @@
 use serde::Serialize;
 
-use super::{color::Color, line_style::LineStyle, Formatter};
+use super::{color::Color, line_style::LineStyle, smoothness::Smoothness, Formatter};
 
 #[derive(Serialize)]
 #[serde(rename_all = "camelCase")]
@@ -246,7 +246,7 @@ pub struct LabelLine {
     length: Option<f64>,
 
     #[serde(skip_serializing_if = "Option::is_none")]
-    smooth: Option<bool>,
+    smooth: Option<Smoothness>,
 
     #[serde(skip_serializing_if = "Option::is_none")]
     min_turn_angle: Option<f64>,
@@ -288,8 +288,8 @@ impl LabelLine {
         self
     }
 
-    pub fn smooth(mut self, smooth: bool) -> Self {
-        self.smooth = Some(smooth);
+    pub fn smooth<F: Into<Smoothness>>(mut self, smoothness: F) -> Self {
+        self.smooth = Some(smoothness.into());
         self
     }